CN120380818A

CN120380818A - Radio frequency exposure management for multiple radios

Info

Publication number: CN120380818A
Application number: CN202380084434.1A
Authority: CN
Inventors: J·纳达库杜蒂; L·卢; P·古基安
Original assignee: Qualcomm Inc
Current assignee: Qualcomm Inc
Priority date: 2022-12-21
Filing date: 2023-12-20
Publication date: 2025-07-25
Also published as: JP2026501179A; EP4639976A1; KR20250121971A; WO2024137795A1

Abstract

Techniques and apparatus for managing radio frequency (RF) exposure for multiple radios are described. An example method of wireless communication by a wireless device generally includes determining a first exposure associated with a first radio for a first transmission in a first time interval; determining a first allowable transmit power associated with a second radio for a second time interval based at least in part on the first exposure associated with the first radio; and transmitting a first signal at a first transmit power in the second time interval using the second radio based on the first allowable transmit power.

Description

Radio frequency exposure management for multiple radios

Cross Reference to Related Applications

The present application claims priority from U.S. patent application Ser. No. 18/545,751, filed on Ser. No. 2023, 12, and 19, which claims the benefit of U.S. provisional patent application Ser. No. 63/476,618, filed on Ser. No. 2022, 12, and 21, which are hereby incorporated by reference in their entirety for all purposes as if fully set forth herein.

Technical Field

Aspects of the present disclosure relate to wireless communications, and more particularly, to Radio Frequency (RF) exposure compliance.

Background

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, broadcast, and so on. Modern wireless devices, such as cellular telephones, are often required to meet Radio Frequency (RF) exposure restrictions set by certain government and international standards and regulations. To ensure compliance with standards, such devices typically undergo a broad authentication process before being shipped to the marketplace. To ensure that the wireless device complies with the RF exposure limit, techniques have been developed that enable the wireless device to evaluate the RF exposure from the wireless device and adjust the transmit power of the wireless device accordingly to comply with the RF exposure limit.

Disclosure of Invention

The systems, methods, and devices of the present disclosure each have several aspects, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of the present disclosure as expressed by the claims which follow, some features will now be discussed briefly. After considering this discussion, and particularly after reading the section entitled "detailed description" one will understand how the features of this disclosure provide advantages that include improved wireless communication performance.

Certain aspects of the subject matter described in this disclosure may be implemented in a method for wireless communication by a wireless device. The method generally includes determining a first exposure associated with a first radio for a first transmission over a first time interval, determining a first allowable transmit power associated with a second radio for a second time interval based at least in part on the first exposure associated with the first radio, and transmitting a first signal at the first transmit power over the second time interval using the second radio based on the first allowable transmit power.

Certain aspects of the subject matter described in this disclosure may be implemented in an apparatus for wireless communication. The apparatus generally includes one or more memories that collectively store executable instructions, and one or more processors coupled to the one or more memories. The one or more processors are collectively configured to execute the executable instructions to cause the apparatus to determine a first exposure associated with a first radio for a first transmission within a first time interval, determine a first allowable transmit power associated with a second radio for a second time interval based at least in part on the first exposure associated with the first radio, and control to transmit a first signal at the first transmit power within the second time interval using the second radio based on the first allowable transmit power.

Certain aspects of the subject matter described in this disclosure may be implemented in an apparatus for wireless communication. The apparatus generally includes means for determining a first exposure associated with a first radio for a first transmission during a first time interval. The apparatus also includes means for determining a first allowable transmit power associated with a second radio for a second time interval based at least in part on the first exposure associated with the first radio. The apparatus also includes means for transmitting a first signal at a first transmit power over the second time interval using the second radio based on the first allowable transmit power.

Certain aspects of the subject matter described in this disclosure may be implemented in a computer-readable medium. The computer-readable medium has instructions stored thereon that, when executed by an apparatus, cause the apparatus to perform operations. The operations include determining a first exposure associated with a first radio for a first transmission within a first time interval. The operations also include determining a first allowable transmit power associated with a second radio for a second time interval based at least in part on the first exposure associated with the first radio. The operations also include transmitting, using the second radio, a first signal at a first transmit power for the second time interval based on the first allowable transmit power.

Other aspects provide an apparatus operable, configured, or otherwise adapted to perform any one or more of the foregoing methods and/or those described elsewhere herein, a non-transitory computer-readable medium comprising instructions that, when executed by a processor of an apparatus, cause the apparatus to perform the foregoing methods and those described elsewhere herein, a computer program product embodied on a computer-readable storage medium comprising code for performing the foregoing methods and those described elsewhere herein, and/or an apparatus comprising means for performing the foregoing methods and those described elsewhere herein. By way of example, an apparatus may comprise a processing system, a device with a processing system, or a processing system cooperating over one or more networks.

To the accomplishment of the foregoing and related ends, one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed.

Drawings

So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to some aspects thereof which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only certain typical aspects of this disclosure and are therefore not to be considered limiting of its scope, for the description may admit to other equally effective aspects.

Fig. 1 is a block diagram conceptually illustrating an example wireless communication network.

Fig. 2 is a block diagram conceptually illustrating a design of an example Base Station (BS) and a User Equipment (UE).

Fig. 3 is a block diagram of an example Radio Frequency (RF) transceiver.

Fig. 4A, 4B, and 4C are diagrams illustrating examples of transmit power over time following a time-averaged RF exposure limit.

Fig. 5 is an illustration of an example processing architecture for distributing energy among multiple radios.

Fig. 6A is a timing diagram illustrating an example of RF exposure management for a wireless device having two radios, in accordance with certain aspects of the present disclosure.

Fig. 6B is a timing diagram illustrating an example of RF exposure management depicted in fig. 6A, which is performed within a time window (T) associated with a time-averaged RF exposure limit, in accordance with certain aspects of the present disclosure.

Fig. 7A is a timing diagram illustrating an example of RF exposure management for a wireless device having three radios, in accordance with certain aspects of the present disclosure.

Fig. 7B is a timing diagram illustrating an example of RF exposure management depicted in fig. 7A, which is performed within a time window (T) associated with a time-averaged RF exposure limit, in accordance with certain aspects of the present disclosure.

Fig. 8 is a flowchart illustrating example operations for wireless communication by a wireless device, in accordance with certain aspects of the present disclosure.

Fig. 9 illustrates a communication device (e.g., UE) that may include various components configured to perform the operations of the techniques disclosed herein, in accordance with certain aspects of the disclosure.

To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one aspect may be beneficially utilized on other aspects without specific recitation.

Detailed Description

Aspects of the present disclosure provide apparatus, methods, processing systems, and computer readable media for Radio Frequency (RF) exposure management for multiple radios.

In some cases, a wireless device may be equipped with multiple radios for wireless communications, such as Code Division Multiple Access (CDMA), evolved universal terrestrial radio access (E-UTRA), fifth generation new radio (5G NR), institute of Electrical and Electronics Engineers (IEEE) 802.11, bluetooth, non-terrestrial networks, and so forth. For example, some wireless devices may support multi-mode (e.g., E-UTRA and 5G NR, 5G NR and IEEE 802.11, etc.) and/or multi-band (e.g., sub-6 gigahertz (GHz) and millimeter wave (mmWave) bands) communications via multiple transmit antennas (or radios) for simultaneous or concurrent transmission. To ensure compliance with RF exposure limits, the wireless device may limit the maximum combined instantaneous transmit power for multi-mode/multi-band communication. To allow for multi-radio communications, wireless devices may be configured with maximum allowable transmit power per radio for each transmit scenario, including single-radio scenarios and multi-radio scenarios (e.g., multi-mode/multi-band scenarios), where the transmit scenarios may correspond to one or more radios, one or more frequency bands, one or more antennas, and/or one or more exposure scenarios (e.g., head exposure, limb exposure, body exposure, or hot spot exposure) for transmitting over a time interval. The wireless device may be configured with a look-up table of maximum allowable transmit powers corresponding to various transmit scenarios, and the wireless device may use particular values of the maximum allowable transmit powers in the look-up table depending on the transmit scenario. For a multi-radio scenario, the look-up table may have pre-restricted backoff for each of the radios.

Aspects of the present disclosure provide apparatus and methods for RF exposure management for multiple radios. The wireless device may sequentially evaluate the RF exposure compliance per radio such that the combined transmit power determined for each radio within different time intervals in the sequence of time intervals meets the RF exposure limit. For example, for a future time interval, the wireless device may determine the transmit power of the first radio based on past RF exposure generated by the second radio over a past time interval. The transmit power of the first radio may be the remaining transmit power available for transmission in a future time interval after accounting for past RF exposure by the second radio. The wireless device may continue to perform such multi-radio exposure evaluations. For example, the wireless device may first determine the RF exposure and corresponding transmit power associated with a first time interval for one radio (e.g., the one radio is a higher priority radio or primary radio) and may use any remaining available RF exposure for another radio (e.g., a lower priority radio or secondary radio) for a second time interval after the first time interval. The wireless device may extend the sequential exposure evaluation to any number of radios. For example, a third time interval (which may be the same or different than the second time interval) may be used for a third radio (e.g., an even lower priority radio or a tertiary radio) that may expose the remaining exposure left using a combination of the first radio and the second radio.

The apparatus and methods for multi-radio RF exposure management described herein may facilitate improved wireless communication performance (e.g., improved signal quality at a receiver, reduced latency, improved throughput, etc.). For example, multi-radio RF exposure management may allow a wireless device to evaluate RF exposure per time interval and assign any remaining exposure to other radios. Multi-radio RF exposure management may allow wireless devices to select relatively high priority radios to prioritize exposure, which may improve wireless communication performance for a particular radio.

As used herein, radio may refer to one or more active frequency bands, transceivers, and/or Radio Access Technologies (RATs) for wireless communications (e.g., code Division Multiple Access (CDMA), long Term Evolution (LTE), NR, IEEE 802.11, bluetooth, etc.). For example, for uplink carrier aggregation or dual connectivity in LTE and/or NR, each of the active component carriers (or serving cells) for wireless communication may be considered a separate radio. Similarly, multiband transmission of IEEE 802.11 communications can be considered as a separate radio for each band (e.g., 2.4GHz, 5GHz, or 6 GHz).

The following description provides examples of RF exposure compliance in a communication system, and is not intended to limit the scope, applicability, or examples set forth in the claims. Changes may be made in the function and arrangement of elements discussed without departing from the scope of the disclosure. Various examples may omit, replace, or add various procedures or components as appropriate. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Furthermore, features described with respect to some examples may be combined in some other examples. For example, an apparatus may be implemented or a method practiced using any number of the aspects set forth herein. In addition, the scope of the present disclosure is intended to cover such devices or methods practiced using other structures, functionality, or both in addition to or instead of the various aspects of the present disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of the present claims. The word "exemplary" is used herein to mean "serving as an example, instance, or illustration. Any aspect described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other aspects.

Generally, any number of wireless networks may be deployed in a given geographic area. Each wireless network may support a particular Radio Access Technology (RAT) and may operate on one or more frequencies. RATs may also be referred to as radio technologies, air interfaces, etc. Frequencies may also be referred to as carriers, subcarriers, frequency channels, tones, subbands, and so forth. Each frequency may support a single RAT in a given geographical area in order to avoid interference between wireless networks of different RATs, or may support multiple RATs.

The techniques described herein may be used for various wireless networks and radio technologies. Although aspects may be described herein using terms commonly associated with 3G, 4G, and/or new radio (e.g., 5G NR) wireless technologies, aspects of the present disclosure may be applied to other generation-based communication systems and/or to wireless technologies such as 802.11, 802.15, etc.

NR access may support various wireless communication services such as enhanced mobile broadband (eMBB) targeting a wide bandwidth (e.g., 80 megahertz (MHz) or more), millimeter wave (mmWave) targeting high carrier frequencies (e.g., 24GHz to 53GHz or more), large-scale Machine Type Communication (MTC) targeting non-backward compatible MTC technologies, and/or critical tasks targeting ultra-reliable low latency communications (URLLC). These services may include latency and reliability specifications. These services may also have different Transmission Time Intervals (TTIs) to meet corresponding quality of service (QoS) requirements. Furthermore, these services may coexist in the same subframe. NR supports beamforming and can dynamically configure beam direction. Multiple-input multiple-output (MIMO) transmission using precoding may also be supported as a multi-layer transmission. Aggregation of multiple cells may be supported.

Example Wireless communication networks and devices

Fig. 1 illustrates an example wireless communication network 100 in which aspects of the present disclosure may be implemented. For example, the wireless communication network 100 may be a NR system (e.g., a 5G NR network), an evolved Universal terrestrial radio Access (E-UTRA) system (e.g., a 4G network), a Universal Mobile Telecommunications System (UMTS) (e.g., a second generation (2G)/third generation (3G) network) or a Code Division Multiple Access (CDMA) system (e.g., a 2G/3G network), or may be configured for communication in accordance with an IEEE standard, such as one or more of the 802.11 standards. As shown in fig. 1, UE 120a includes an RF exposure manager 122 that ensures RF exposure compliance across multiple radios, in accordance with aspects of the present disclosure.

As illustrated in fig. 1, wireless communication network 100 may include a plurality of BSs 110a-110z (each also referred to herein individually as BS 110, or collectively as BS 110) and other network entities. BS 110 may provide communication coverage for a particular geographic area (sometimes referred to as a "cell") that may be stationary or mobile depending on the location of the mobile BS. In some examples, BS 110 may interconnect with each other and/or connect to one or more other BSs or network nodes (not shown) in wireless communication network 100 through various types of backhaul interfaces (e.g., direct physical connection, wireless connection, virtual network, etc.) using any suitable transport network. In the example shown in fig. 1, BSs 110a, 110b, and 110c may be macro BSs for macro cells 102a, 102b, and 102c, respectively. BS 110x may be a pico BS of pico cell 102 x. BSs 110y and 110z may be femto BSs for femto cells 102y and 102z, respectively. The BS may support one or more cells.

BS 110 communicates with UEs 120a-120y (each also referred to herein individually as UE 120, or collectively as UE 120) in wireless communication network 100. UEs 120 (e.g., 120x, 120y, etc.) may be dispersed throughout wireless communication network 100, and each UE 120 may be stationary or mobile. Wireless communication network 100 may also include relay stations (e.g., relay station 110 r) (also referred to as relays, etc.) that receive transmissions of data and/or other information from upstream stations (e.g., BS 110a or UE 120 r) and transmit the transmissions of data and/or other information to downstream stations (e.g., UE 120 or BS 110), or relay transmissions between UEs 120 to facilitate communications between devices.

Network controller 130 may communicate with a collection of BSs 110 and provide coordination and control (e.g., via backhaul) for these BSs 110. In some cases, such as in a 5G NR system, the network controller 130 may include a Centralized Unit (CU) and/or a Distributed Unit (DU). In some aspects, the network controller 130 may communicate with a core network 132 (e.g., a 5G core network (5 GC)) that provides various network functions such as access and mobility management, session management, user plane functions, policy control functions, authentication server functions, unified data management, application functions, network exposure functions, network repository functions, network slice selection functions, and the like.

In this disclosure, the term "beam" may be used in various contexts. A beam may be used to refer to a set of gains and/or phases (e.g., precoding weights or in-phase weights) applied to antenna elements in a UE and/or BS for transmission or reception. The term "beam" may also refer to an antenna or radiation pattern of a signal transmitted when gain and/or phase is applied to an antenna element. Other references to beams may include one or more characteristics or parameters associated with the antenna (radiation) pattern, such as angle of arrival (AoA), angle of departure (AoD), gain, phase, directivity, beamwidth, beam direction in azimuth and elevation (relative to a reference plane), peak sidelobe ratio, or antenna port associated with the antenna (radiation) pattern. The term "beam" may also refer to an associated number and/or configuration of antenna elements (e.g., a uniform linear array, a uniform rectangular array, or other uniform array).

Fig. 2 illustrates example components of BS 110a and UE 120a (e.g., wireless communication network 100 of fig. 1) that may be used to implement aspects of the present disclosure.

At BS 110a, transmit processor 220 may receive data from data source 212 and control information from controller/processor 240. The control information may be used for a Physical Broadcast Channel (PBCH), a Physical Control Format Indicator Channel (PCFICH), a physical hybrid automatic repeat request (HARQ) indicator channel (PHICH), a Physical Downlink Control Channel (PDCCH), group common PDCCH (GC PDCCH), and the like. The data may be for a Physical Downlink Shared Channel (PDSCH) or the like. A Medium Access Control (MAC) -control element (MAC-CE) is a MAC layer communication structure that may be used for control command exchange between wireless nodes. The MAC-CE may be carried in a shared channel such as PDSCH, physical Uplink Shared Channel (PUSCH), or physical side link shared channel (PSSCH).

Processor 220 may process (e.g., encode and symbol map) the data and control information to obtain data symbols and control symbols, respectively. The transmit processor 220 may also generate reference symbols such as for a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), a PBCH demodulation reference signal (DMRS), and a channel state information reference signal (CSI-RS). A Transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, and/or the reference symbols, if applicable, and may provide output symbol streams to Modulators (MODs) in the transceivers 232a-232 t. Each modulator 232a-232t in the transceiver may process a respective output symbol stream (e.g., for Orthogonal Frequency Division Multiplexing (OFDM), etc.) to obtain an output sample stream. Each of the transceivers 232a-232t may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. Downlink signals from transceivers 232a-232t may be transmitted via antennas 234a-234t, respectively.

At UE 120a, antennas 252a-252r may receive the Downlink (DL) signals from BS 110a and may provide the received signals to transceivers 254a-254r, respectively. The transceivers 254a-254r may condition (e.g., filter, amplify, downconvert, and digitize) respective received signals to obtain input samples. Each demodulator (DEMOD) in transceivers 232a-232t may further process the input samples (e.g., for OFDM, etc.) to obtain received symbols. MIMO detector 256 may obtain the received symbols from all of the demodulators in transceivers 254a-254r, perform MIMO detection on the received symbols (where applicable), and provide detected symbols. Receive processor 258 may process (e.g., demodulate, deinterleave, and decode) the detected symbols, provide decoded data for UE 120a to a data sink 260, and provide decoded control information to a controller/processor 280.

On the uplink, at UE 120a, transmit processor 264 may receive and process data from data source 262 (e.g., for a Physical Uplink Shared Channel (PUSCH)) and control information from controller/processor 280 (e.g., for a Physical Uplink Control Channel (PUCCH)). The transmit processor 264 may also generate reference symbols for reference signals (e.g., for Sounding Reference Signals (SRS)). The symbols from transmit processor 264 may be pre-decoded (if applicable) by a TX MIMO processor 266, further processed (e.g., for single carrier frequency division multiplexing (SC-FDM), etc.) by Modulators (MOD) in transceivers 254a through 254r, and transmitted to BS110 a. At BS110 a, an Uplink (UL) signal from UE 120a may be received by antenna 234, processed by demodulators in transceivers 232a-232t, detected by a MIMO detector 236 (if applicable), and further processed by a receive processor 238 to obtain decoded data and control information transmitted by UE 120 a. The receive processor 238 may provide the decoded data to a data sink 239 and the decoded control information to a controller/processor 240.

Memories 242 and 282 may store data and program codes for BS 110a and UE 120a, respectively. Scheduler 244 may schedule UEs for data transmission on the downlink and/or uplink.

Antenna 252, processors 266, 258, 264 and/or controller/processor 280 of UE 120a and/or antenna 234, processors 220, 230, 238 and/or controller/processor 240 of BS110 a may be used to perform the various techniques and methods described herein. As shown in fig. 2, controller/processor 280 of UE 120a has an RF exposure manager 281 that represents RF exposure manager 122, in accordance with aspects described herein. Although shown at a controller/processor, other components of UE 120a and BS110 a may be used to perform the operations described herein.

NR may utilize OFDM with Cyclic Prefix (CP) on uplink and downlink. NR may use Time Division Duplexing (TDD) to support half-duplex operation. OFDM and SC-FDM divide the system bandwidth into multiple orthogonal subcarriers, which are also often referred to as tones, bins, etc. Each subcarrier may be modulated with data. The modulation symbols may be transmitted in the frequency domain using OFDM and in the time domain using SC-FDM. The interval between adjacent subcarriers may be fixed and the total number of subcarriers may depend on the system bandwidth. The system bandwidth may also be divided into sub-bands. For example, one subband may cover multiple Resource Blocks (RBs).

Although UE 120a is described with reference to fig. 1 and 2 as communicating with a BS and/or within a network, UE 120a may be configured to communicate directly with/transmit directly to another UE 120 or to/transmit directly to another wireless device without relaying the communication through the network. In some aspects, BS 110a illustrated in fig. 2 and described above is an example of another UE 120.

Example RF transceiver

Fig. 3 is a block diagram of an example RF transceiver circuit 300 in accordance with certain aspects of the present disclosure. RF transceiver circuitry 300 includes at least one Transmit (TX) path 302 (also referred to as a transmit chain) for transmitting signals via one or more antennas 306 and at least one Receive (RX) path 304 (also referred to as a receive chain) for receiving signals via antennas 306. When TX path 302 and RX path 304 share antenna 306, these paths may be connected to the antenna via interface 308, which may include any of a variety of suitable RF devices, such as switches, diplexers, multiplexers, and the like.

Receiving in-phase (I) or quadrature (Q) baseband analog signals from digital-to-analog converter (DAC) 310, TX path 302 may include baseband filter (BBF) 312, mixer 314, driver Amplifier (DA) 316, and Power Amplifier (PA) 318.BBF 312, mixer 314, and DA 316 may be included in one or more Radio Frequency Integrated Circuits (RFICs). For some implementations, PA 318 may be external to the RFIC.

BBF 312 filters the baseband signals received from DAC 310 and mixer 314 mixes the filtered baseband signals with a transmit Local Oscillator (LO) signal to convert the baseband signals of interest to a different frequency (e.g., up-convert from baseband to radio frequency). The frequency conversion process produces sum and difference frequencies between the LO frequency and the frequency of the baseband signal of interest. The sum and difference frequencies are referred to as beat frequencies. The beat frequency is typically in the RF range such that the signal output by mixer 314 is typically an RF signal that may be amplified by DA 316 and/or by PA 318 before being transmitted through antenna 306. Although one mixer 314 is illustrated, several mixers may be used to up-convert the filtered baseband signal to one or more intermediate frequencies and thereafter up-convert the intermediate frequency signal to a frequency for transmission.

RX path 304 may include a Low Noise Amplifier (LNA) 324, a mixer 326, and a baseband filter (BBF) 328.LNA 324, mixer 326, and BBF 328 may be included in one or more RFICs, which may be the same RFICs as those including TX path components, or may be different RFICs. The RF signal received via antenna 306 may be amplified by LNA 324 and mixer 326 mixes the amplified RF signal with a receive Local Oscillator (LO) signal to convert the RF signal of interest to a different baseband frequency (e.g., down-convert). The baseband signal output by mixer 326 may be filtered by BBF 328 before being converted to a digital I or Q signal by analog-to-digital converter (ADC) 330 for digital signal processing.

Some transceivers may employ a frequency synthesizer with a Voltage Controlled Oscillator (VCO) to generate a stable, tunable LO frequency with a particular tuning range. Thus, the transmit LO frequency may be generated by TX frequency synthesizer 320, which may be buffered or amplified by amplifier 322 before being mixed with the baseband signal in mixer 314. Similarly, the receive LO frequency may be generated by an RX frequency synthesizer 332, which may be buffered or amplified by an amplifier 334 before being mixed with the RF signal in mixer 326.

The controller 336 may direct the operation of the RF transceiver circuitry 300, such as transmitting signals via the TX path 302 and/or receiving signals via the RX path 304. The controller 336 may be a processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other Programmable Logic Device (PLD), discrete gate or transistor logic, discrete hardware components, or any combination thereof. Memory 338 may store data and program codes for operating RF transceiver circuit 300. The controller 336 and/or memory 338 may include control logic. In some cases, controller 336 may determine the transmit power applied to TX path 302 (e.g., certain gain levels applied at BBF 312, DA 316, and/or PA 318) following RF exposure limits set by country-specific regulations and/or international standards, as further described herein.

Example RF exposure compliance

RF exposure may be expressed in terms of Specific Absorption Rate (SAR), which measures the energy absorption per unit mass of human tissue and may have units of watts per kilogram (W/kg). RF exposure may also be expressed in terms of Power Density (PD), which measures energy absorption per unit area, and may have units of milliwatts per square centimeter (mW/cm ²). In some cases, a maximum grant exposure (MPE) limit (in the form of a PD) may be imposed on wireless devices that use transmit frequencies above 6 GHz. MPE limits are area-based exposure supervision measures, such as energy density limits, defined as the number X (watts per square meter (W/m ²)) averaged over a defined area and time averaged over a frequency-dependent time window to prevent the risk of human exposure as indicated by tissue temperature changes.

SAR may be used to evaluate RF exposure for transmission frequencies less than 6GHz, which encompasses wireless communication technologies such as 2G/3G (e.g., CDMA), 4G (e.g., LTE), 5G (e.g., NR in the 6GHz band), IEEE 802.11ac, and the like. PD may be used to evaluate RF exposure for transmission frequencies above 6GHz, which encompasses wireless communication technologies such as IEEE 802.11ad, 802.11ay, 5G in the millimeter wave band, and the like. Thus, different metrics may be used to evaluate RF exposure for different wireless communication technologies.

A wireless device (e.g., UE 120) may use multiple wireless communication technologies to transmit signals simultaneously. For example, the wireless device may transmit signals simultaneously using a first wireless communication technology (e.g., 3G, 4G, 5G, etc.) operating at 6GHz or below and a second wireless communication technology (e.g., millimeter wave 5G, ieee 802.11ad, or 802.11ay in the 24GHz to 60GHz band) operating above 6 GHz. In certain aspects, the wireless device may transmit signals simultaneously using a first wireless communication technology (e.g., 3G, 4G, 5G, IEEE 802.11ac, etc., in the frequency band below 6GHz, where RF exposure is measured in SAR) and a second wireless communication technology (e.g., 5G, IEEE 802.11ad, 802.11ay, etc., in the 24GHz to 60GHz frequency band, where RF exposure is measured in PD). As used herein, the frequency band below 6GHz may include frequency bands of 300MHz to 6,000MHz in some examples, and may include frequency bands in the 6,000MHz and/or 7,000MHz range in some examples.

In some cases, compliance with RF exposure limits may be performed as a time-averaged RF exposure assessment over a specified time window (T) associated with the RF exposure limit (e.g., 2 seconds for millimeter wave or 60GHz band, 100 seconds or 360 seconds for a band of < 6GHz, etc.).

Fig. 4A is a graph 400A of transmit power over time (P (T)) over a time window (T) associated with a time-averaged RF exposure limit, in accordance with certain aspects of the present disclosure. For example, in certain transmit occasions within the time window (T), the instantaneous transmit power may exceed the maximum time average transmit power level (P _limit). In some cases, the maximum time-averaged transmit power level may take into account uncertainty of the transceiver circuitry, such as temperature drift, component age, etc. The transmit power may be greater than the maximum time-averaged transmit power level P _limit. In some cases, the UE may transmit at P _max, P _max being the maximum transmit power supported by the UE. In some cases, in some transmission occasions, the UE may transmit with a transmit power less than or equal to the maximum time average transmit power level P _limit. The maximum time average transmit power level P _limit represents a time average threshold in terms of transmit power of the RF exposure limit within the time window (T), and in some cases P _limit may be referred to as a maximum time average power level or limit, or in terms of exposure, a maximum time average RF exposure level or limit. In some cases, the maximum time-averaged transmit power level P _limit may correspond to a maximum allowable transmit power as described herein. Diagram 400A also illustrates gaps between transmit bursts, where the gaps represent periods during which no transmissions are output from the device.

In some cases, the transmit power may be maintained at a maximum time-averaged transmit power level (e.g., P _limit) allowed for RF exposure compliance that enables continuous transmission during a time window. For example, fig. 4B is a graph 400B of transmit power over time (P (t)) illustrating an example in which transmit power is limited to P _limit, in accordance with certain aspects of the present disclosure. As shown, the UE may follow the RF exposure limit for continuous transmission at P _limit.

Fig. 4C is a graph 400C illustrating transmit power over time (P (T)) for a time-averaged mode that provides reserve power to enable continuous transmission within a time window (T), in accordance with certain aspects of the present disclosure. As shown, the transmit power may be backed off from a maximum instantaneous power (P _max) to a reserved power (P _reserve) such that the UE may continue to transmit at a lower power (P _reserve) to maintain continuous transmission (e.g., maintain a radio connection with the receiving entity) during the time window. in fig. 4C, the area between P _max and P _reserve over the duration of P _max may be equal to the area between P _limit and P _reserve over time window T, such that the area of transmit power (P (T)) in fig. 4C is equal to the area of P _limit over time window T. Such an area can be considered to use 100% of the energy (transmit power or exposure) to keep up with the time-averaged RF exposure limit. Without reserve power P _reserve, the transmitter may transmit at P _max for a portion of the time window and shut down for the remainder of the time window to ensure compliance with the time-averaged RF exposure limit. In some aspects, P _reserve is set to a fixed power for serving some purpose (e.g., reserving power for certain communications). The transmission duration under P _max may be referred to as a burst transmission time (or high power duration). When more margin is available in the future (after T seconds), the transmitter may be allowed to transmit again at higher power (e.g., in short bursts at P _max).

In some aspects, in the time-averaged mode illustrated in fig. 4C, the UE may transmit at a power higher than the average power level but less than P _max. Although a single transmission burst is illustrated in fig. 4C, it should be appreciated that the UE may instead utilize multiple transmission bursts within a time window (T), e.g., as described herein with respect to fig. 4A, wherein the transmission bursts may be separated by a period during which the transmission power is maintained at or below P _reserve. Further, it should be appreciated that the transmit power of each transmit burst may vary (within the burst and/or compared to other bursts), and that at least a portion of the burst may be transmitted at a power above a maximum average power level (e.g., P _limit).

While fig. 4A-4C illustrate successive transmissions within a window, occasion, burst, etc., it should be understood that a transmit duty cycle may be implemented. In such implementations, the transmit power may be periodically zero and maintained at a higher level (e.g., a level as illustrated in fig. 4A-4C) during other portions of the duty cycle. As used herein, a duty cycle of a transmission may refer to a portion (e.g., 5 ms) of a particular period (e.g., 500 ms) in which one or more signals are transmitted. In some cases, the duty cycle may be standardized (e.g., predetermined) with a particular RAT and/or change over time, e.g., due to changes in radio conditions, mobility, and/or user behavior.

In some cases, the wireless communication device may evaluate RF exposure compliance using a maximum allowable transmit power (P _limit) corresponding to a time-averaged RF exposure limit. The maximum allowable transmit power may correspond to a transmit power that satisfies a time-averaged RF exposure limit assuming the wireless device transmits for the entire duration of a time window associated with the time-averaged RF exposure limit (e.g., 2 seconds for the mmWave or 60GHz band, 100 seconds or 360 seconds for the band of +.6 GHz, etc.), for example, as depicted in fig. 4B. To ensure compliance with the time-averaged RF exposure limit, the wireless device may have a transmit power not greater than a maximum allowable transmit power. Such a scheme may facilitate simplified RF exposure assessment without having to determine a rolling average of RF exposure over a given time window associated with a time-averaged RF exposure limit, and may be referred to as an uneven RF exposure assessment.

In some cases, a wireless device may be equipped with multiple radios for wireless communication, such as Code Division Multiple Access (CDMA), evolved universal terrestrial radio access (E-UTRA), fifth generation new radio (5G NR), IEEE 802.11, bluetooth, non-terrestrial networks, and the like. For example, some wireless devices may support multi-mode (e.g., E-UTRA and 5G NR, 5G NR and IEEE 802.11, etc.) and/or multi-band (e.g., below 6GHz band and mmWave band) communications via multiple transmit antennas (or radios) for simultaneous or concurrent transmission. To ensure compliance with RF exposure limits, the wireless device may limit the maximum combined instantaneous transmit power for multi-mode/multi-band communication.

To allow for multi-radio communication, the wireless device may be configured with a maximum allowable transmit power per radio for each transmit scenario, including multi-radio scenarios (e.g., multi-mode/multi-band scenarios), where the transmit scenario may correspond to one or more radios, one or more frequency bands, one or more antennas, and/or one or more exposure scenarios (e.g., head exposure, limb exposure, body exposure, or hot spot exposure) for transmitting within a time interval. The wireless device may be configured with a look-up table of maximum allowable transmit power per radio corresponding to various transmission scenarios, and the wireless device may use a particular value of the maximum allowable transmit power per radio in the look-up table according to the transmission scenario. For a multi-radio scenario, the look-up table may have pre-restricted backoff (or pre-adjusted P _limit) for each of the radios.

For example, assuming that the wireless device has two radios, the wireless device may have a value of maximum allowable transmit power for the first radio and the second radio of the transmission scenario when the radios are used concurrently or within the same time interval. When only the first radio is used, the wireless device may have a value of the maximum allowable transmit power associated with the first radio for the transmission scenario, and when only the second radio is used, the wireless device may have another value of the maximum allowable transmit power associated with the second radio for the transmission scenario. The wireless device may have a maximum allowable transmit power per radio for different frequency bands, different antennas, and/or different exposure scenarios.

Since the total transmit power that satisfies the RF exposure limit may vary depending on the transmission scenario (e.g., frequency band, antenna, exposure scenario, etc.), the wireless device may be configured with a value of maximum allowable transmit power per radio for multiple transmission scenarios. Because the maximum allowable transmit power per radio for each transmit scenario is determined under the RF exposure test, performing the test for each transmit scenario and populating the look-up table with values of the maximum allowable transmit power per radio requires time and other resources (e.g., test equipment and/or analog data). Further, such a lookup table may use some amount of memory storage on the wireless device.

Example RF exposure management for multiple radios

Aspects of the present disclosure provide apparatus and methods for multi-radio RF exposure management, e.g., without pre-populating a look-up table with individual power limits for radios in a multi-radio scenario. The wireless device may sequentially evaluate the RF exposure compliance per radio such that the combined transmit power determined for each radio within different time intervals in the sequence of time intervals meets the RF exposure limit. For example, the wireless device may first determine the RF exposure and corresponding transmit power associated with a first time interval for one radio (e.g., the one radio is a higher priority radio or primary radio) and may use any remaining available RF exposure for another radio (e.g., a lower priority radio or secondary radio) for a second time interval after the first time interval. The wireless device may extend the sequential exposure evaluation to any number of radios. For example, a third time interval (which may be the same or different than the second time interval) may be used for a third radio (e.g., an even lower priority radio or a tertiary radio) that may expose the remaining exposure left using a combination of the first radio and the second radio. Unlike some pre-populated static look-up tables, the maximum allowable transmit power of a second radio of lower priority may not be pre-limited for a given transmission scenario based on the maximum allowable transmit power of a first radio of higher priority and stored in the look-up table as a pair of allowable transmit powers for that scenario.

The apparatus and methods for multi-radio RF exposure management described herein potentially enable higher transmit power per radio than other solutions, and thus may be advantageous for improving wireless communication performance (e.g., improving signal quality at the receiver, reducing latency, improving throughput, etc.). For example, multi-radio RF exposure management may allow a wireless device to evaluate RF exposure per time interval and assign any remaining exposure to other radios. Multi-radio RF exposure management may allow wireless devices to select high priority radios to prioritize exposure, which may improve wireless communication performance for particular radios (e.g., high priority radios and/or other radios). Multi-radio RF exposure management may allow a wireless device to reduce the size of a lookup table of maximum allowable transmit power. Multi-radio RF exposure management may allow wireless device manufacturers to avoid performing exposure tests for multi-radio exposure scenarios and populating complex look-up tables as described herein before. The wireless device may store the maximum allowable transmit power per radio for various transmit scenarios (e.g., frequency bands, antennas, exposure scenarios, etc.) associated with a single radio, rather than for various transmit scenarios (e.g., frequency bands, antennas, exposure scenarios, etc.) associated with various radio combinations (e.g., only a first radio, only a second radio, and/or a combination of a first radio and a second radio), where the static limits for each radio are pre-filled for a given transmit scenario.

For certain aspects, multi-radio RF exposure management may be performed using a centralized processing architecture at, for example, a modem (and/or processor) associated with one or more radios. Fig. 5 is an illustration of an example processing architecture 500 for distributing energy across multiple radios, in accordance with certain aspects of the present disclosure. For example, the radios 502a-502d of the wireless devices (e.g., radio 1, radio 2, etc.) may report past RF exposure usage (or generation) to the RF exposure manager 510 (e.g., similar to the RF exposure manager 122 of fig. 1), and the RF exposure manager 510 may provide the radios 502a-502d that are to transmit within a time interval with an allowable transmit power (e.g., a maximum allowable instantaneous transmit power) associated with the time interval. The RF exposure manager 510 may use sequential exposure evaluations to determine allowable transmit power, as described further herein.

It should be understood that the RF exposure manager 510 and/or radio depicted in the processing architecture 500 may be implemented in hardware, software, or a combination of both. For example, the RF exposure manager 510 and/or radio included in the processing architecture 500 may be implemented in a modem, RF circuitry (e.g., transceiver), memory blocks, registers, processing blocks, and/or instructions (e.g., software code or executable instructions). The executable instructions may be stored in memory and executed on a processor (e.g., an application processor and/or a modem processor).

Fig. 6A is a timing diagram 600A illustrating an example of RF exposure management for a wireless device (e.g., UE 120) having two radios. In this example, the wireless device may have an RF exposure manager (e.g., RF exposure manager 510 in fig. 5), a first radio (e.g., radio 1 in fig. 5), and a second radio (e.g., radio 2 in fig. 5), e.g., as described herein with respect to fig. 5. The radios may (or are expected to) transmit within the same time period, so the assessment of RF exposure compliance takes into account the transmission activity of both radios. For example, the RF exposure manager may select a maximum allowable transmit power (P _limit) associated with a current transmit scenario (e.g., frequency band, antenna, exposure scenario, etc.) for the first radio, and the RF exposure manager may provide P _limit to the first radio, such as RF circuitry (e.g., transceiver circuitry 300) associated with the first radio. The RF exposure manager may select P _limit from a look-up table that includes values of P _limit associated with the first radio for various transmission scenarios as described herein. The first radio may transmit signals at a transmit power 604 less than or equal to the corresponding P _limit for a first time interval 602 (Δt _i) following a corresponding time-averaged RF exposure limit. The RF exposure manager can obtain a transmit power report associated with the first radio for the first time interval 602 from the first radio. The transmit power report may include (or indicate) the transmit power 604 used by the first radio during the first time interval 602. For example, the transmit power report may include an average transmit power used by the first radio during the first time interval 602.

The RF exposure manager can determine a maximum allowable instantaneous transmit power 608 associated with a second radio for a second time interval 606 (Δt _i+1), wherein the second time interval 606 immediately follows the first time interval 602 in time. In some cases, the second time interval 606 may be later in time than the first time interval 602, but not adjacent to the first time interval 602. The second time interval 606 may be a future time interval when the RF exposure manager is determining the maximum allowable instantaneous transmit power 608. The first time interval 602 and the second time interval 606 may be in a sequence of time intervals such that the first time interval 602 and the second time interval 606 are consecutive time intervals in the sequence. To determine the maximum allowable instantaneous transmit power 608 of the second radio, the rf exposure manager may determine a normalized exposure associated with the first radio for the first time interval 602. Normalized exposure associated with a first radio) The determination may be made according to the following expression:

(1)

Wherein the method comprises the steps of May be an average transmit power (e.g., in milliwatts (mW)) used by the first radio during the first time interval 602, andIs the maximum allowable transmit power (e.g., in mW) associated with the first radio for the first time interval 602. That is, the normalized exposure associated with the first radio may be equal to the transmit power used by the first radio during the first time interval 602 divided by the maximum allowable transmit power associated with the first radio.

The RF exposure manager may determine an exposure margin associated with the second radio based on the normalized exposure associated with the first radio) Wherein the exposure margin is a remaining exposure available for the second radio. The exposure margin may be determined according to the following expression:

(2)

That is, as the normalized value (of P _limit), the exposure margin associated with the second radio may be equal to the difference between one and the normalized exposure associated with the first radio determined according to expression (1).

The RF exposure manager may determine a maximum allowable instantaneous transmit power associated with the second radio based on the exposure margin). For example, the maximum allowable instantaneous transmit power associated with the second radio may be determined according to the following expression:

(3)

Wherein the method comprises the steps of Is the maximum allowable transmit power associated with the second radio for the current transmit scenario (e.g., band, antenna, exposed scenario, etc.). That is, the maximum allowable instantaneous transmit power associated with the second radio may be equal to the product of the exposure margin and the maximum allowable transmit power (P _limit) associated with the second radio.

The RF exposure manager may provide the maximum allowable instantaneous transmit power determined for the second time interval to RF circuitry (e.g., transceiver circuitry) associated with the second radio. The sum of the normalized exposure associated with the first radio for the first time interval 602 and the normalized exposure associated with the second radio for the second time interval 606 meets the RF exposure limit (e.g., normalization limit one). For example, the sum of normalized exposures of the first radio and the second radio may be less than a normalization limit (e.g., one). In some cases, a reserved amount may be maintained for the second radio or one or more other radios (such as a third radio), as further described herein. In some cases, the wireless device may transmit another signal at the transmit power 610 for a second time interval 606 using the first radio. Such transmissions may be used to determine the transmit power of the second radio in a next time interval (not shown), e.g., as described herein with respect to fig. 6B.

In certain aspects, the RF exposure manager may determine a maximum allowable instantaneous transmit power based on a duty cycle associated with the radio. The duty cycle may indicate a maximum amount of time that the radio is expected to transmit within a certain period of time. In some cases, the duty cycle may be configured according to a particular radio access technology, such as a Time Division Duplex (TDD) uplink-downlink mode associated with global system for mobile communications (GSM), LTE, and/or NR. For example, for the first time interval 602, the rf exposure manager may determine a maximum allowable instantaneous transmit power (MAIP _first) associated with the first radio according to the following expression:

(4a)

Where duty_cycle represents a duty cycle associated with a first radio for a first time interval. For the second time interval 606, the rf exposure manager may determine the maximum allowable instantaneous transmit power (MAIP sec) of the second radio according to the following expression:

(4b)

where duty_cycle represents a duty cycle associated with a second radio for a second time interval.

The RF exposure management described herein may allow a wireless device to store a maximum allowable transmit power (P _limit) for various transmit scenarios per radio (e.g., frequency bands, antennas, exposure scenarios, etc.), e.g., without pre-limiting multi-radio combinations of transmit power per radio. The described RF exposure management may allow the wireless device to consider the actual transmit power used by the priority radio to determine the maximum allowable instantaneous transmit power associated with the secondary radio. The RF exposure management described herein may be applied with a time-averaged implementation for RF exposure compliance, e.g., as described herein with respect to fig. 4A-4C. For example, the wireless device may switch between performing the RF exposure management and application time-average implementations described herein. The time-averaged implementations may include the wireless device determining a maximum allowable transmit power (e.g., P _limit) that meets the RF exposure limit for a future time interval based on past transmit powers in a time window associated with the time-averaged RF exposure limit.

In certain aspects, a wireless device may have antennas arranged in antenna groups, where an antenna group may include one or more antennas (or antenna modules) associated with one or more radios. The antenna groups may be configured and/or operated so as to be mutually exclusive in terms of RF exposure. That is, RF exposure by one antenna group may have no effect on RF exposure by another antenna group, for example, because the antenna groups are disposed in different locations of the wireless device. RF exposure compliance and corresponding transmit power levels may be determined separately for each antenna group, allowing multiple antenna groups to transmit during the same time period. RF exposure compliance of antenna groups may be performed in parallel (e.g., concurrently together). In some cases, a wireless device may perform multi-radio RF exposure management as described herein with respect to antenna groups. The wireless device may store a maximum allowable transmit power associated with the radios per antenna group and the wireless device may evaluate RF exposure compliance for the multiple radios per antenna group. For example, where transmissions within the same time period relate to antennas from different antenna groups, the radio associated with the antenna groups may transmit the respective maximum allowable transmit power (e.g., P _limit) as described herein.

Because the multi-radio RF exposure management described herein uses normalized exposure and normalized energy allocation, wireless devices can evaluate RF exposure compliance across various frequency bands with different RF exposure limits, such as the frequency band below 6GHz and/or the mmWave frequency band. For example, the first radio may be configured to transmit signals in a frequency band below 6GHz and the second radio may be configured to transmit signals in the mmWave frequency band.

In certain aspects, the RF exposure manager can select a first radio among a plurality of radios (e.g., radio 1 through radio 4 in fig. 5) having transmissions to be output within the first time interval 602. For example, the RF exposure manager may identify that the first radio has a higher priority than other radios to be allocated energy within the first time interval 602. The priority associated with the radio may be based on one or more criteria, such as duty cycle, frequency band, quality of service (QoS) characteristics (e.g., latency, data rate, priority level, etc.), and type of service (e.g., URLLC, eMBB, internet of things (IoT), voice traffic, video traffic, interactive games, mission critical data, etc.), as illustrative, non-limiting examples.

Fig. 6B is a timing diagram 600B illustrating an example of RF exposure management depicted in fig. 6A, which is performed within a time window (T) associated with a time-averaged RF exposure limit. In this example, the RF exposure manager determines a maximum allowable exposure of the second radio within a future time interval (e.g., the second time interval 606) based on past exposures of the first radio within past time intervals (e.g., the first time interval 602). The sum of the normalized exposures of the first radio and the second radio may satisfy the RF exposure limit (e.g., normalization limit one). For example, a normalized exposure set 612 including a first exposure 614 associated with a first radio and a second exposure 616 associated with a second radio may satisfy the RF exposure limit. Each of the normalized exposures may correspond to a different time interval in the sequence of time intervals (e.g., first time interval 602 and second time interval 606). The RF exposure manager may continue to perform RF exposure assessment for the second radio for a future time interval based on the transmit power of the first radio for the past interval. The RF exposure manager may determine a maximum allowable instantaneous transmit power associated with the second radio for the future time interval based on past exposures generated by the first radio during the past time interval. Assuming that the time interval (e.g., Δt) in which the first radio and the second radio are located is much smaller in duration than the time window (T) associated with the time-averaged RF exposure limit, the resulting average total exposure within that time window will conform to the time-averaged RF exposure limit. For example, each of the first time interval 602 and the second time interval 606 may be a portion of a time window (T) associated with a time-averaged RF exposure limit.

In certain aspects, the multi-radio RF exposure management described herein may be applied to more than two radios transmitting within the same time period. For example, the exposure margin left by the first radio may be used for the second radio and the remaining exposure margin may be used for the third radio.

It is noted that in some cases, the duration of the time interval (e.g., Δt) in which the first radio and the second radio (or generally any radio of the wireless device) are located may be less than the regulatory time window. For example, the regulatory time window may be a time window (T) associated with an RF exposure limit, such as a time-averaged RF exposure limit. In general, the multi-radio RF exposure management described herein may achieve a time interval of any suitable duration.

Fig. 7A is a timing diagram 700A illustrating an example of RF exposure management for a wireless device (e.g., UE 120) having three radios. In this example, the wireless device may have an RF exposure manager (e.g., RF exposure manager 510 in fig. 5), a first radio (e.g., radio 1 in fig. 5), a second radio (e.g., radio 2 in fig. 5), and a third radio (e.g., radio 3 in fig. 5), e.g., as described herein with respect to fig. 5. The RF exposure manager may perform the same operations for the first radio and the second radio, as described herein with respect to fig. 6A. In this example, the second time interval 606 (Δt _i+1) may be a past time interval when the RF exposure manager is determining the maximum allowable instantaneous transmit power 714 of the third radio within a third time interval 712 (Δt _i+2), which immediately follows the second time interval 606 in time. In some cases, the third time interval 712 may be later in time than the second time interval 606, but not adjacent to the second time interval 606. The second radio may transmit signals at a transmit power 708 less than or equal to the corresponding maximum allowable instantaneous transmit power for a second time interval 606 (Δt _i+1) following the corresponding time-averaged RF exposure limit. The RF exposure manager can obtain a transmit power report associated with the second radio for the second time interval 606 from the second radio. The transmit power report may include or indicate the transmit power 708 (e.g., average transmit power) used by the second radio for the second time interval 606.

The RF exposure manager may determine a maximum allowable instantaneous transmit power associated with the third radio for the third time interval 712 based on the remaining exposure margin and past exposures used by the second radio during the second time interval 606. The RF exposure manager may determine the exposure margin associated with the third radio, e.g., according to the following expression):

(5)

Wherein the method comprises the steps ofCan be determined, for example, according to expression (2), andMay be the average transmit power used by the second radio during the second time interval 606. That is, as a normalized value (of P _limit), the exposure margin associated with the third radio may be equal to the difference between the exposure margin associated with the second radio and the normalized exposure produced by the second radio within the second time interval 606.

The RF exposure manager may determine a maximum allowable instantaneous transmit power 714 associated with the third radio based on the exposure margin. For example, the maximum allowable instantaneous transmit power associated with the third radio [ ]) The determination may be made according to the following expression:

(6)

Wherein the method comprises the steps of Is the maximum allowable transmit power associated with the third radio for the current transmit scenario (e.g., band, antenna, exposed scenario, etc.). That is, the maximum allowable instantaneous transmit power associated with the third radio may be equal to the product of the remaining exposure margin available and the maximum allowable transmit power (P _limit) associated with the third radio. Here, the RF exposure manager may also consider a duty cycle associated with the third radio. For example, the maximum allowable instantaneous transmit power (MAIP _th) associated with the third radio may be determined according to the following expression:

(7)

Where duty_cycle represents the duty cycle associated with the third radio for the third time interval 712.

The RF exposure manager may provide the maximum allowable instantaneous transmit power determined for the third time interval to RF circuitry (e.g., transceiver circuitry) associated with the third radio. The sum of the normalized exposure associated with the first radio for the first time interval 602, the normalized exposure associated with the second radio for the second time interval 606, and the normalized exposure associated with the third radio for the third time interval 712 meets the RF exposure limit (e.g., normalization limit one). For example, the sum of normalized exposures of the first radio, the second radio, and the third radio may be less than a normalized limit (e.g., one). In some cases, the wireless device may transmit a signal at transmit power 716 using the first radio and another signal at transmit power 718 using the second radio within the third time interval 712. Such transmissions may be used to determine the transmit power of the third radio over a future time interval (not shown), e.g., as described herein with respect to fig. 7B.

Fig. 7B is a timing diagram 700B illustrating an example of RF exposure management depicted in fig. 7A, which is performed within a time window (T) associated with a time-averaged RF exposure limit. In this example, the RF exposure manager determines a maximum allowable exposure of the third radio within a future time interval (e.g., third time interval 712) based on past exposures of the first radio and the second radio within respective past time intervals (e.g., first time interval 602 and second time interval 606). The sum of the normalized exposures of the first radio, the second radio, and the third radio may satisfy the RF exposure limit (e.g., normalized limit one). For example, the normalized exposure set 720 including a first exposure 722 associated with the first radio, a second exposure 724 associated with the second radio, and a third exposure 726 associated with the third radio may satisfy the RF exposure limit, wherein each of the normalized exposures corresponds to a different time interval in the sequence of time intervals (e.g., the first time interval 602, the second time interval 606, and the third time interval 712). The RF exposure manager may continue to perform RF exposure evaluation on the radio, as described herein with respect to fig. 7A.

The transmit power available for the low priority radio is based on the exposure margin left by the high priority radio. In the case where the high priority radio is transmitting at its P _limit, the low priority radio will have no margin available to transmit signals. Since the radios may be allowed to consume all exposure margin in the operations described herein with respect to fig. 6A and 7A, the wireless device may reserve an amount of energy for some radios, such as the second radio described with respect to fig. 6A or the second and/or third radios described with respect to fig. 7A. To avoid dropping links for low priority radios, the transmit power of the high priority radio may be less than or equal to a percentage (x) of P _limit.

In the dual-radio example, the transmit power of the first radio may be allowed to be no more than x multiplied by P _limit #) Wherein x is less than 1.0, thereby ensuring that the second radio has at leastIs not limited to the margin of (1). In certain aspects, the RF exposure manager may consider a duty cycle associated with the first radio. The RF exposure manager may determine, for example, a maximum allowable instantaneous transmit power (MAIP _ first) associated with the first radio as the product of x and P _limit divided by a duty cycle (e.g.,). The RF exposure manager may determine a normalized exposure associated with the first radio, as provided in expression (1). The RF exposure manager may determine any remaining exposure margin for the second radio according to the following expression):

(8)

Where x is a reserved amount or power limit associated with the first radio. That is, the remaining exposure margin for the second radio may be equal to the difference between the reserved amount and the exposure margin. The RF exposure manager may determine an exposure margin associated with the second radio according to the following expression:

(9)

The RF exposure manager may determine a maximum allowable instantaneous transmit power (MAIP sec) associated with the second radio based on the corresponding exposure margin (e.g., according to expression (3)) and in some cases based on the duty cycle (e.g., according to expression (4 b)). In certain aspects, the RF exposure manager may not consider the remaining exposure margin. The RF exposure manager may apply a predetermined allocation to each of the radios, e.g., normalizing the exposure margin for the first radio allocation (E.g., 70%) and a normalized exposure margin (1-) (E.g., 30%).

In certain aspects, the reservation may be applied to additional radios. In a three-radio example, the first reserved amount (x) may represent the maximum energy that may be assigned to the first radio, and the second reserved amount (y) may represent the maximum energy that may be assigned to the second radio, with a remaining exposure margin reserved for the third radio (e.g.,) The sum of the first reserved quantity and the second reserved quantity is less than one%). For example, the RF exposure manager may determine an exposure margin associated with the second radio according to expression (9). In some cases, the RF exposure manager may determine an exposure margin associated with the second radio based on the second reserved amount (y):

(10)

the RF exposure manager may determine a maximum allowable instantaneous transmit power (MAIP sec) associated with the second radio based on the corresponding exposure margin (e.g., according to expression (3)) and in some cases based on the duty cycle (e.g., according to expression (4 b)).

The RF exposure manager may determine the normalized exposure produced by the second radio over a time interval (e.g., second time interval 606) according to the following expression:

(11)

The RF exposure manager may determine any margin remaining for the third radio according to the following expression ):

(12)

Wherein the method comprises the steps ofAn exposure margin associated with the second radio may be represented, as determined according to expression (9). That is, the margin of remaining for the third radio may be equal to the difference between the margin of exposure associated with the second radio and the exposure generated by the second radio. The RF exposure manager may determine an exposure margin associated with the third radio according to the following expression:

(13)

Where y is a reserved amount or power limit associated with the second radio. The RF exposure manager may determine a maximum allowable instantaneous transmit power associated with the third radio based on the corresponding exposure margin, e.g., according to expression (6). In some cases, the maximum allowable instantaneous transmit power (MAIP _tlird) associated with the third radio may be determined based on the duty cycle associated with the third radio, e.g., according to expression (7). In certain aspects, the RF exposure manager may not consider the remaining exposure margin. The RF exposure manager may apply a predetermined allocation to each of the radios, e.g., normalizing the exposure margin for the first radio allocation Assigning a normalized exposure margin to the second radioAnd a normalized exposure margin (1-)。

As an example of allocation among N active radios, a wireless device may allocate a portion of the exposure margin among the first N-1 radios, while the remainder may be allocated to the nth radio. In this example, x ₁ to x _N-1 represent a minimum percentage of the exposure allocation to the first N-1 radios, and the nth radio obtains the remainder (e.g., 1- (x ₁+x₂+..+x_N-1)), where the sum of the allocations to the first N-1 radios may be less than one (e.g., x ₁+x₂+ …+x_N-1 < 1.0). For each of the radios, after a given radio transmits within a time interval (e.g., Δt or first time interval 602), the exposure associated with the respective radio and the remaining exposure margin for the other radios may be determined.

For the first radio (radio 1), the wireless device may determine the exposure margin according to the following expression:

For the first radio, the wireless device may determine the maximum allowable instantaneous transmit power (MAIP _radi1) according to the following expression:

For the first radio, the wireless device may determine the RF exposure generated by the first radio as follows:

for a first radio, the wireless device may determine the remaining exposure for the other radios as follows:

for the second radio (radio 2), the wireless device may determine the exposure margin according to the following expression:

For the second radio, the wireless device may determine the maximum allowable instantaneous transmit power (MAIP _radio2) according to the following expression:

for the second radio, the wireless device may determine the RF exposure generated by the first radio as follows:

For the second radio, the wireless device may determine the remaining exposure for the other radios as follows:

for the (N-1) th radio, the wireless device may determine the exposure margin according to the following expression:

for the (N-1) th radio, the wireless device may determine the maximum allowable instantaneous transmit power (MAIP _radio _N-1) according to the following expression:

For the (N-1) th radio, the wireless device may determine the RF exposure generated by the first radio as follows:

for the (N-1) th radio, the wireless device may determine the remaining exposure for the other radios as follows:

for the nth radio, the wireless device may determine the remaining exposure margin as follows:

For the nth radio, the wireless device may determine the maximum allowable instantaneous transmit power (MAIP _ radioN) as follows:

In certain aspects, the RF exposure manager may not consider the remaining exposure margin. The RF exposure manager may apply a predetermined allocation to each of the radios, e.g., normalizing the exposure margin for the first radio allocation Assigning a normalized exposure margin to the second radioIn this way, a normalized exposure margin is allocated to the (N-1) th radioAnd a normalized exposure margin (1-)。

In certain aspects, the RF exposure manager may split an exposure margin associated with the second radio between the second radio and any other radio (e.g., the third radio)) Instead of determining the individual exposure margin of the third radio according to expression (13). Generally, for an N-radio scenario, the allocation of the total exposure margin between radios may not take into account any or be based on the residual margin, e.g., as described herein according to expressions (8) through (13).

It is noted that in some cases, the duration of the time interval (e.g., Δt) in which the first radio, the second radio, and the third radio (or generally any radio of the wireless device) are located may be less than the regulatory time window. For example, the regulatory time window may be a time window (T) associated with an RF exposure limit, such as a time-averaged RF exposure limit. In general, the multi-radio RF exposure management described herein may achieve a time interval of any suitable duration.

Fig. 8 is a flowchart illustrating example operations 800 for wireless communication in accordance with certain aspects of the present disclosure. The operations 800 may be performed, for example, by a wireless device (e.g., the UE 120a in the wireless communication network 100). The operations 800 may be implemented as software components executing and running on one or more processors (e.g., the controller/processor 280 of fig. 2). Additionally, the signaling and/or receiving by the wireless device in operation 800 may be implemented, for example, by one or more antennas (e.g., antenna 252 of fig. 2). In certain aspects, the transmission and/or reception of signals by the wireless device may be accomplished via a bus interface of one or more processors (e.g., controller/processor 280) to obtain and/or output signals.

The operations 800 may optionally begin at block 802, where the wireless device may determine a first exposure associated with a first radio for a first transmission within a first time interval (e.g., the first time interval 602). For example, the wireless device may determine a normalized exposure associated with the first radio according to expression (1), as described herein with respect to fig. 6A. In some aspects, the wireless device may determine the first exposure based at least in part on a first maximum time-averaged transmit power level (P _{limit_first}) associated with the first radio.

At block 804, the wireless device may determine a first allowable transmit power associated with a second radio for a second time interval (e.g., second time interval 606) based at least in part on a first exposure associated with the first radio. For example, the wireless device may determine a maximum allowable instantaneous transmit power associated with the second radio according to expression (3) or (4 b), as described herein with respect to fig. 6A. In some aspects, the wireless device may further determine the first allowable transmit power based on a second maximum time-averaged transmit power level (P _{limit_sec}) associated with the second radio. The second time interval may be adjacent in time to the first time interval.

At block 806, the wireless device may transmit a first signal at a first transmit power using a second radio for a second time interval based on the first allowable transmit power. The first transmit power may be less than or equal to the first allowable transmit power determined at block 804. In some cases, the wireless device may transmit the second signal at the second transmit power for a second time interval using the first radio. The second transmit power may be less than or equal to the second allowable transmit power. The second allowable transmit power (e.g., MAIP _first) may be determined based at least in part on the exposure margin allocated to the first radio and a first maximum time-averaged transmit power level associated with the first radio. The exposure margin allocated to the first radio may be one. In some cases, the wireless device may determine a maximum allowable instantaneous transmit power associated with the first radio based on a duty cycle associated with the first radio, e.g., according to expression (4 a).

In certain aspects, the first allowable transmit power associated with the second radio may be based on an exposure margin. To determine the first allowable transmit power, the wireless device may determine a first exposure margin associated with the second radio based on a first exposure associated with the first radio, e.g., according to expression (2). The wireless device may determine a first allowable transmit power based on the first exposure margin and a second maximum time-averaged transmit power level (e.g., P _{limit_sec}) associated with the second radio. To determine the first allowable transmit power, the wireless device may determine the first exposure margin as a difference between one and the first exposure, e.g., according to expression (2). To determine the first allowable transmit power, the wireless device may determine the first allowable transmit power as a product of the first exposure margin and the first maximum time-averaged transmit power level, e.g., according to expression (3).

In certain aspects, the wireless device may determine the second exposure margin for the second radio as a difference (e.g., 1-x) between one and a third exposure margin (e.g., x) allocated to the first radio. The wireless device may determine the available exposure margin as a difference between a third exposure margin (x) allocated to the first radio and the first exposure (e.g., x-norm. Exp. First). The wireless device may determine the first exposure margin as a sum of the second exposure margin and the available exposure margin (e.g., (1-x) + (x-norm. Exp. First) = (1-norm. Exp. First)). In some cases, the third exposure margin allocated to the first radio may be one. The entire exposure margin may be assigned to a particular radio.

In some cases, the wireless device may determine the first allowable transmit power based on a duty cycle associated with the second radio, e.g., according to expression (4 b). The duty cycle may represent a maximum amount of time the second radio is expected to transmit within a certain period of time. If the duty cycle associated with the second radio is relatively low (e.g., < 50%), the second radio may be able to transmit at a higher transmit power. If the duty cycle associated with the second radio is relatively high (e.g., > 50%), the second radio may be allocated a lower transmit power.

For certain aspects, the wireless device may determine a transmit power of a third radio or more, e.g., as described herein with respect to fig. 7A. The wireless device may determine a second exposure margin associated with a third radio for a third time interval (e.g., third time interval 712) based on the first exposure margin and a second exposure associated with a second radio for a second transmission within the second time interval, e.g., according to expression (5). The wireless device may determine a second allowable transmit power associated with the third radio for the third time interval based on the second exposure margin and a second maximum time-averaged transmit power level (e.g., P _{limit_third}) associated with the third radio, e.g., according to expression (6).

In some cases, the wireless device may determine a third exposure margin (e.g., 1-x-y) for a third radio as a difference of one and a sum of a minimum exposure margin (x) allocated to the first radio and a minimum exposure margin (y) allocated to the second radio. The wireless device may determine an available exposure margin (e.g., norm. Exp. Margin. Sec-norm. Exp. Sec) as a difference between a first exposure margin (norm. Exp. Margin. Sec) and a second exposure (norm. Exp. Sec) allocated to the second radio. The wireless device may determine the second exposure margin as a sum of a third exposure margin and an available exposure margin for a third radio (e.g., (1-x-y) + (norm. Exp. Margin. Sec-norm. Exp. Sec)).

The wireless device may transmit a second signal at a second transmit power for a third time interval using a third radio based on the second allowable transmit power. For example, the second transmit power may be less than or equal to the second allowable transmit power. The third time interval may have the same duration as the second time interval or a different duration than the second time interval. The third time interval may be adjacent in time to the second time interval, and the second time interval may be between the first time interval and the third time interval in time. In some cases, the wireless device may transmit a third signal during a third time interval using the first radio and a fourth signal during the third time interval using the second radio. In some cases, the wireless device may determine the second allowable transmit power based on a duty cycle associated with the third radio.

In certain aspects, a wireless device may reserve energy for some radios. For example, to determine the first allowable transmit power, the wireless device may determine the first allowable transmit power further based on a first power limit applied to the first radio, e.g., according to expressions (8) and (9). To determine the second allowable transmit power, the wireless device may determine the second allowable transmit power further based on a second power limit applied to the second radio, e.g., according to expressions (11) through (13).

For certain aspects, wireless devices may be assigned antenna groups with mutually exclusive RF exposure. The wireless device may determine a second allowable transmit power associated with a third radio associated with the first antenna group, wherein the first radio and the second radio are associated with the second antenna group. The determination of the second allowable transmit power may be independent of transmissions associated with the second antenna group.

In certain aspects, radios may be associated with different frequency bands and corresponding RF exposure limits. For example, the wireless device may transmit the second signal using the first radio in a frequency band below 6GHz, and the wireless device may transmit the first signal using the second radio in an mmWave frequency band.

For certain aspects, a wireless device may select a first radio among a plurality of radios based on one or more priorities associated with the radios. For example, the wireless device may select the first radio based on the first radio having a higher priority than the other radios. The first radio may have a higher transmission priority than the second radio. For example, the duty cycle may represent a priority, wherein the duty cycle of the first radio may be greater than the second radio. In some cases, the service type may indicate priority. For example, a first radio may be used to transmit interactive game traffic and a second radio may be used to transmit conversational voice traffic, so in such a scenario the first radio has a higher priority of transmission than the second radio.

For certain aspects, the wireless device may allocate an exposure margin between radios. For example, the wireless device may determine a first exposure margin for the first radio and a second exposure margin for any other radio, wherein a sum of the first exposure margin and the second exposure margin may be less than or equal to a threshold (e.g., 1). The wireless device may assign a portion of the second exposure margin to each of the other radios. In some cases, the wireless device may equally allocate portions of the second exposure margin to each of the other radios (e.g., (1-norm. Exp. First)/(N-1), where N is the total number of radios). In some cases, the second exposure margin allocation portion may be different between other radios. The wireless device may determine a first allowable transmit power associated with the first radio based on the first exposure margin, and the wireless device may determine a second allowable transmit power associated with each of the other radios based on a respective portion of the second exposure margin. The wireless device may transmit a first signal at a first transmit power for a first time interval based on a first allowable transmit power, and the wireless device may transmit a second signal at a second transmit power for a corresponding second time interval based on a respective second allowable transmit power for each of the other radios.

Although the examples depicted in fig. 1-8 are described herein with respect to a UE performing various methods for providing RF exposure compliance for ease of understanding, aspects of the present disclosure may also be applied to other wireless devices performing RF exposure management described herein, such as wireless stations, access points, base stations, and/or Customer Premises Equipment (CPE). Further, while these examples are described with respect to communication between a UE (or other wireless device) and a network entity, the UE or other wireless device may communicate with a device other than the network entity (e.g., another UE) or with another device in the user's home that is not the network entity.

It should be appreciated that the multi-radio RF exposure management described herein may achieve desired wireless communication performance, such as reduced latency, increased uplink data rate, and/or an enlarged communication range, for example, due to increased exposure margin that may be assigned to multiple radios.

Example communication device

Fig. 9 illustrates a communication device 900 (e.g., UE 120) that may include various components (e.g., corresponding to the component plus function components) configured to perform operations of the techniques disclosed herein, such as the operations illustrated in fig. 8. The communication device 900 includes a processing system 902 that can be coupled to a transceiver 908 (e.g., transmitter and/or receiver). The transceiver 908 is configured to transmit and receive signals for the communication device 900, such as the various signals described herein, via the antenna 910. The processing system 902 can be configured to perform the processing functions of the communication device 900, including processing signals received by and/or to be transmitted by the communication device 900.

The processing system 902 includes a processor 904 coupled to a computer-readable medium/memory 912 via a bus 906. In certain aspects, the computer-readable medium/memory 912 is configured to store instructions (e.g., computer-executable code) that, when executed by the processor 904, cause the communication device 900 to perform the operations 800 illustrated in fig. 8 or other operations for performing the various techniques discussed herein for providing RF exposure compliance. In certain aspects, the computer-readable medium/memory 912 stores code 914 for determining, code 916 for transmitting (or outputting), or any combination thereof.

In certain aspects, the processing system 902 has circuitry 920 configured to implement code stored in the computer-readable medium/memory 912. In certain aspects, the circuitry 920 is coupled to the processor 904 and/or the computer-readable medium/memory 912 via the bus 906. For example, the circuitry 920 includes circuitry 922 for determining, circuitry 924 for transmitting (or outputting), or any combination thereof.

In some examples, the means for transmitting or transmitting (or means for outputting for transmission) may include transceiver 254 and/or antenna 252 of UE 120 and/or transceiver 908 and antenna 910 of communication device 900 in fig. 9 illustrated in fig. 2.

In some cases, a device may not actually transmit, for example, signals and/or data, but may have an interface (means for outputting) for outputting signals and/or data for transmission. For example, the processor may output signals and/or data to a Radio Frequency (RF) front end via a bus interface for transmission. Similarly, a device may not actually receive signals and/or data, but may have an interface (means for obtaining) for obtaining signals and/or data received from another device. For example, the processor may obtain (or receive) signals and/or data from the RF front end via the bus interface for reception. In various aspects, the RF front-end may include various components including transmit and receive processors, transmit and receive MIMO processors, modulators, demodulators, and the like, such as depicted in the example of fig. 2.

In some examples, the means for determining may include various processing system components, such as the processor 904 in fig. 9, or aspects of the UE 120 depicted in fig. 2, including the receive processor 258, the transmit processor 264, the TX MIMO processor 266, and/or the controller/processor 280.

Example aspects

Specific examples of implementations are described in the following numbered clauses:

Aspect 1a method of wireless communication by a wireless device includes determining a first exposure associated with a first radio for a first transmission over a first time interval, determining a first allowable transmit power associated with a second radio for a second time interval based at least in part on the first exposure associated with the first radio, and transmitting a first signal at the first transmit power over the second time interval using the second radio based on the first allowable transmit power.

Aspect 2 the method of aspect 1, wherein determining the first exposure comprises determining the first exposure based at least in part on a first maximum time-averaged transmit power level associated with the first radio, and determining the first allowable transmit power comprises determining the first allowable transmit power further based on a second maximum time-averaged transmit power level associated with the second radio.

Aspect 3 the method according to aspect 1 or 2, the method further comprising transmitting a second signal with a second transmit power for the second time interval using the first radio, wherein the first radio has a higher transmit priority than the second radio, and the second time interval is adjacent in time to the first time interval.

Aspect 4 the method of aspect 3, wherein the second transmit power is less than or equal to a second allowable transmit power, and the second allowable transmit power is based at least in part on an exposure margin allocated to the first radio and a first maximum time-averaged transmit power level associated with the first radio.

Aspect 5 the method of aspect 4, further comprising determining the second allowable transmit power based on a duty cycle associated with the first radio.

Aspect 6 the method of aspects 4 or 5, wherein the exposure margin allocated to the first radio is less than or equal to one.

Aspect 7 the method of any one of aspects 1 to 6, wherein determining the first allowable transmit power is further based on a duty cycle associated with the second radio.

Aspect 8 the method of any one of aspects 1 to 7, wherein determining the first allowable transmit power comprises determining a first exposure margin associated with the second radio based on the first exposure associated with the first radio, and determining the first allowable transmit power based on the first exposure margin and a second maximum time-averaged transmit power level associated with the second radio.

Aspect 9 the method of aspect 8, wherein determining the first allowable transmit power further comprises determining the first exposure margin as a difference between one and the first exposure.

Aspect 10 the method of aspects 8 or 9, wherein determining the first exposure margin comprises determining a second exposure margin for the second radio as a difference between a third exposure margin allocated to the first radio and an available exposure margin as a difference between the third exposure margin allocated to the first radio and the first exposure, and determining the first exposure margin as a sum of the second exposure margin and the available exposure margin.

Aspect 11 the method of aspect 10, wherein the third exposure margin allocated to the first radio is less than or equal to one.

Aspect 12 the method of any one of aspects 8 to 11, wherein determining the first allowable transmit power further comprises determining the first allowable transmit power as a product of the first exposure margin and the second maximum time-averaged transmit power level.

Aspect 13 the method of aspect 8, further comprising determining a second exposure margin associated with a third radio for a third time interval based on the first exposure margin and a second exposure associated with the second radio for a second transmission in the second time interval, determining a second allowable transmit power associated with the third radio for the third time interval based on the second exposure margin and a second maximum time-averaged transmit power level associated with the third radio, and transmitting a second signal at a second transmit power in the third time interval using the third radio based on the second allowable transmit power.

Aspect 14 the method of aspect 13, determining the second exposure margin comprises determining a third exposure margin for the third radio as a difference of a sum of a minimum exposure margin allocated to the first radio and a minimum exposure margin allocated to the second radio, and determining an available exposure margin as a difference of the first exposure margin and the second exposure margin allocated to the second radio, and determining the second exposure margin as a sum of the third exposure margin and the available exposure margin for the third radio.

Aspect 15 the method of aspects 13 or 14, wherein the third time interval has the same duration as the second time interval.

Aspect 16 the method according to any one of aspects 13 to 15, further comprising transmitting a third signal in the third time interval using the first radio, and transmitting a fourth signal in the third time interval using the second radio, wherein the third time interval is temporally adjacent to the second time interval, and wherein the second time interval is temporally between the first time interval and the third time interval.

Aspect 17 the method of any one of aspects 13-16, wherein determining the second allowable transmit power comprises determining the second allowable transmit power further based on a duty cycle associated with the third radio.

Aspect 18 the method of any one of aspects 13 to 17, wherein determining the second allowable transmit power comprises determining the second allowable transmit power further based on a second power limit applied to the second radio.

Aspect 19 the method of any one of aspects 1-18, wherein determining the first allowable transmit power comprises determining the first allowable transmit power further based on a first power limit applied to the first radio.

Aspect 20 the method of any one of aspects 1 to 19, further comprising determining a second allowable transmit power associated with a third radio, the third radio being associated with a first antenna group, wherein the first radio and the second radio are associated with a second antenna group.

Aspect 21 the method of aspect 20, wherein the determination of the second allowable transmit power is independent of transmissions associated with the second antenna group.

Aspect 22 the method of any one of aspects 1 to 21, further comprising transmitting a second signal using the first radio in a frequency band below 6GHz, wherein transmitting the first signal comprises transmitting the first signal using the second radio in an mmWave frequency band.

Aspect 23 the method of any one of aspects 1 to 22, further comprising selecting the first radio among the radios based on one or more priorities associated with a plurality of radios.

Aspect 24 an apparatus comprising one or more memories collectively storing executable instructions, and one or more processors coupled to the one or more memories, the one or more processors collectively configured to execute the executable instructions and cause the apparatus to perform the method according to any of aspects 1-23.

Aspect 25 an apparatus comprising means for performing the method according to any one of aspects 1 to 23.

Aspect 26 is a non-transitory computer-readable medium comprising computer-executable instructions that, when executed by one or more processors of a processing system, cause the processing system to perform the method of any of aspects 1 to 23.

Aspect 27 a computer program product embodied on a computer-readable storage medium comprising code for performing the method of any of aspects 1 to 23.

The techniques described herein may be used for various wireless communication techniques such as NR (e.g., 5G NR), 3GPP Long Term Evolution (LTE), LTE-advanced (LTE-A), code Division Multiple Access (CDMA), time Division Multiple Access (TDMA), frequency Division Multiple Access (FDMA), orthogonal Frequency Division Multiple Access (OFDMA), single-carrier frequency division multiple access (SC-FDMA), time division synchronous code division multiple access (TD-SCDMA), and other networks. The terms "network" and "system" are often used interchangeably. A CDMA network may implement radio technologies such as Universal Terrestrial Radio Access (UTRA), CDMA2000, and the like. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. cdma2000 covers IS-2000, IS-95, and IS-856 standards. TDMA networks may implement radio technologies such as global system for mobile communications (GSM). An OFDMA network may implement radio technologies such as NR (e.g., 5G RA), evolved UTRA (E-UTRA), ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, flash-OFDMA, and the like. UTRA and E-UTRA are parts of Universal Mobile Telecommunications System (UMTS). LTE and LTE-a are versions of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-a and GSM are described in documents from an organization named "third generation partnership project" (3 GPP). Cdma2000 and UMB are described in documents from an organization named "third generation partnership project 2" (3 GPP 2). NR is an emerging wireless communication technology being developed.

In 3GPP, the term "cell" can refer to a coverage area of a Node B (NB) and/or an NB subsystem serving the coverage area, depending on the context in which the term is used. In an NR system, the terms "cell" and BS, next generation NodeB (gNB or gNodeB), access Point (AP), distributed Unit (DU), carrier wave, or transmission-reception point (TRP) may be used interchangeably. The BS may provide communication coverage for macro cells, pico cells, femto cells, and/or other types of cells. A macro cell may cover a relatively large geographic area (e.g., a few kilometers in radius) and may allow unrestricted access by UEs with service subscription. The pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscription. A femto cell may cover a relatively small geographic area (e.g., home) and may allow limited access by UEs having an association with the femto cell (e.g., UEs in a Closed Subscriber Group (CSG), UEs of users in the home, etc.). The BS for the macro cell may be referred to as a macro BS. The BS for the pico cell may be referred to as a pico BS. The BS for the femto cell may be referred to as a femto BS or a home BS.

The UE may also be referred to as a mobile station, terminal, access terminal, subscriber unit, station, customer Premise Equipment (CPE), cellular telephone, smart phone, personal Digital Assistant (PDA), wireless modem, wireless device, handheld device, laptop, cordless phone, wireless Local Loop (WLL) station, tablet, camera, gaming device, netbook, smartbook, superbook, appliance, medical device or equipment, biometric sensor/device, wearable device (such as a smart watch, smart garment, smart glasses, smart wristband, smart jewelry (e.g., smart ring, smart bracelet, etc.), entertainment device (e.g., music device, video device, satellite radio, etc.), vehicle component or sensor, smart meter/sensor, industrial manufacturing equipment, global positioning system device, or any other suitable device configured to communicate via a wireless or wired medium. Some UEs may be considered Machine Type Communication (MTC) devices or evolved MTC (eMTC) devices. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, and the like, that may communicate with a BS, another device (e.g., a remote device), or some other entity. The wireless node may provide, for example, a connection to a network (e.g., a wide area network such as the internet or a cellular network) or a connection to a network via a wired or wireless communication link. Some UEs may be considered internet of things (IoT) devices, which may be narrowband IoT (NB-IoT) devices.

In some examples, access to the air interface may be scheduled. A scheduling entity (e.g., BS) allocates resources for communications between some or all devices and equipment within a service area or cell of the entity. The scheduling entity may be responsible for scheduling, assigning, reconfiguring, and releasing resources for one or more subordinate entities. That is, for scheduled communications, the subordinate entity uses the resources allocated by the scheduling entity. The base station is not the only entity that can be used as a scheduling entity. In some examples, a UE may serve as a scheduling entity and may schedule resources for one or more subordinate entities (e.g., one or more other UEs), and other UEs may communicate wirelessly using the resources scheduled by the UE. In some examples, the UE may be used as a scheduling entity in a peer-to-peer (P2P) network or in a mesh network. In a mesh network example, UEs may communicate directly with each other in addition to communicating with a scheduling entity.

The methods disclosed herein comprise one or more steps or actions for achieving the method. The steps and/or actions of the methods may be interchanged with one another without departing from the scope of the claims. In other words, unless a specific order of steps or actions is specified, the order and/or use of specific steps and/or actions may be modified without departing from the scope of the claims.

As used herein, "processor," "at least one processor," or "one or more processors" generally refer to a single processor configured to perform one or more operations or multiple processors configured to collectively perform one or more operations. In the case of multiple processors, execution of one or more operations may be divided among the different processors, but one processor may perform multiple operations, and multiple processors may collectively perform a single operation. Similarly, "memory," "at least one memory," or "one or more memories" generally refer to a single memory configured to store data and/or instructions or multiple memories configured to collectively store data and/or instructions.

As used herein, a phrase referring to "at least one of a list of items" refers to any combination of these items (which includes a single member). By way of example, at least one of "a, b, or c" is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination having multiple identical elements (e.g., a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b-b, b-b-c, c-c, and c-c-c, or any other ordering of a, b, and c).

As used herein, the term "determining" encompasses a wide variety of actions. For example, "determining" may include calculating, computing, processing, deriving, generating, investigating, looking up (e.g., looking up in a table, a database or another data structure), ascertaining and the like. Further, "determining" may include receiving (e.g., receiving information), accessing (e.g., accessing data in memory), and so forth. Further, "determining" may include parsing, selecting, choosing, establishing, and the like.

The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language of the claims, wherein reference to an element in the singular is not intended to mean "one and only one" unless specifically so stated, but rather "one or more". The term "some" means one or more unless stated otherwise. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Furthermore, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element should be construed in accordance with the 35 u.s.c. ≡112 (f) specification unless the phrase "means for @ is used to explicitly recite the element or, in the case of method claims, the phrase" step for @.

The various operations of the above-described methods may be performed by any suitable component capable of performing the corresponding functions. The component may include various hardware and/or software components and/or modules including, but not limited to, a circuit, an Application Specific Integrated Circuit (ASIC), or a processor. Generally, where there are operations illustrated in the figures, those operations may have corresponding parts plus functional components with similar numbers.

The various illustrative logical blocks, modules, and circuits described in connection with the disclosure herein may be implemented or performed with a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other Programmable Logic Device (PLD), discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. Although a general purpose processor may be a microprocessor, in the alternative, the processor may be any commercially available processor, controller, microcontroller or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

If implemented in hardware, an example hardware configuration may include a processing system in a wireless node. The processing system may be implemented using a bus architecture. The bus may include any number of interconnecting buses and bridges depending on the specific application of the processing system and the overall design constraints. The bus may link together various circuits including processors, machine-readable media, and bus interfaces. A bus interface may be used to connect network adapters and the like to the processing system via the bus. Network adapters may be used to implement the signal processing functions of the Physical (PHY) layer. In the case of a UE (see fig. 1), a user interface (e.g., keypad, display, mouse, joystick, etc.) may also be connected to the bus. The bus may also link various other circuits such as timing sources, peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further. The processor may be implemented with one or more general-purpose processors and/or special-purpose processors. Examples include microprocessors, microcontrollers, DSP processors, and other circuitry that can execute software. Those skilled in the art will recognize how best to implement the described functionality of the processing system depending on the particular application and the overall design constraints imposed on the overall system.

If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Software should be construed broadly to mean instructions, data, or any combination thereof, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. The processor may be responsible for managing the bus and general-purpose processing, including the execution of software modules stored on a machine-readable storage medium. A computer readable storage medium may be coupled to the processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. By way of example, the machine-readable medium may comprise a transmission line, a carrier wave modulated by data, and/or a computer-readable storage medium having stored thereon instructions, which may all be accessed by a processor through a bus interface. Alternatively or in addition, the machine-readable medium or any portion thereof may be integrated into the processor, such as in the case of having a cache and/or general purpose register file. By way of example, examples of machine-readable storage media may include RAM (random access memory), flash memory, ROM (read only memory), PROM (programmable read only memory), EPROM (erasable programmable read only memory), EEPROM (electrically erasable programmable read only memory), registers, a magnetic disk, an optical disk, a hard disk drive, or any other suitable storage medium, or any combination thereof. The machine-readable medium may be implemented in a computer program product.

A software module may comprise a single instruction, or many instructions, and may be distributed over several different code segments, among different programs, and across multiple storage media. The computer readable medium may include a plurality of software modules. The software modules include instructions that, when executed by an apparatus, such as a processor, cause the processing system to perform various functions. The software modules may include a transmit module and a receive module. Each software module may reside in a single storage device or be distributed across multiple storage devices. By way of example, when a trigger event occurs, a software module may be loaded from the hard disk drive into RAM. During execution of the software module, the processor may load some of the instructions into the cache to increase access speed. One or more cache lines may then be loaded into a general purpose register file for execution by a processor. When reference is made below to the functionality of a software module, it will be understood that such functionality is implemented by the processor when executing instructions from the software module.

Further, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital Subscriber Line (DSL), or wireless technologies such as Infrared (IR), radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk and disc, as used herein, includes Compact Disc (CD), laser disc, optical disc, digital Versatile Disc (DVD), floppy disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Thus, in some aspects, a computer-readable medium may comprise a non-transitory computer-readable medium (e.g., a tangible medium). Moreover, for other aspects, the computer-readable medium may comprise a transitory computer-readable medium (e.g., a signal). Combinations of the above should also be included within the scope of computer-readable media.

Accordingly, certain aspects may include a computer program product for performing the operations presented herein. For example, such a computer program product may comprise a computer-readable medium having instructions stored (and/or encoded) thereon, which instructions (e.g., instructions for performing the operations described herein and illustrated in fig. 8) are capable of being executed by one or more processors to perform the operations described herein.

Furthermore, it should be understood that modules and/or other suitable components for performing the methods and techniques described herein may be downloaded and/or otherwise obtained by a user terminal and/or base station, as applicable. For example, such a device may be coupled to a server to facilitate the transfer of components for performing the methods described herein. Alternatively, the various methods described herein may be provided via storage means (e.g., RAM, ROM, or a physical storage medium such as a Compact Disc (CD) or floppy disk) so that the user terminal and/or base station can obtain the various methods when the storage means is coupled to or provided to the device. Further, any other suitable technique for providing the methods and techniques described herein to a device may be used.

It is to be understood that the claims are not limited to the precise arrangements and instrumentalities illustrated above. Various modifications, changes and variations may be made in the arrangement, operation and details of the methods and apparatus described above without departing from the scope of the claims.

Claims

1. A method for wireless communication by a wireless device, the method comprising:

determining a first exposure associated with a first radio used for a first transmission in a first time interval;

determining a first allowable transmit power associated with a second radio for a second time interval based at least in part on the first exposure associated with the first radio; and

A first signal is transmitted at a first transmit power within the second time interval using the second radio based on the first allowable transmit power.

2. The method according to claim 1, wherein:

Determining the first exposure includes determining the first exposure based at least in part on a first maximum time-averaged transmit power level associated with the first radio; and

Determining the first allowable transmit power includes determining the first allowable transmit power further based on a second maximum time-averaged transmit power level associated with the second radio.

3. The method of claim 1 , further comprising: using the first radio to transmit a second signal at a second transmit power in the second time interval, wherein the first radio has a higher transmit priority than the second radio, and the second time interval is temporally adjacent to the first time interval.

4. The method according to claim 3, wherein:

The second transmit power is less than or equal to a second allowable transmit power; and

The second allowable transmit power is based at least in part on an exposure margin assigned to the first radio and a first maximum time-averaged transmit power level associated with the first radio.

5 . The method of claim 4 , further comprising determining the second allowable transmit power based on a duty cycle associated with the first radio.

The method of claim 4 , wherein the exposure margin assigned to the first radio is less than or equal to one.

7. The method of claim 1, wherein determining the first allowable transmit power is further based on a duty cycle associated with the second radio.

8. The method of claim 1 , wherein determining the first allowable transmit power comprises:

determining a first exposure margin associated with the second radio based on the first exposure associated with the first radio; and

The first allowable transmit power is determined based on the first exposure margin and a second maximum time-averaged transmit power level associated with the second radio.

9. The method of claim 8, wherein determining the first allowable transmit power further comprises determining the first exposure margin as a difference between one and the first exposure.

10. The method of claim 8, wherein determining the first exposure margin comprises:

determining a second exposure margin for the second radio as a difference between one and a third exposure margin assigned to the first radio;

determining an available exposure margin as a difference between the third exposure margin allocated to the first radio and the first exposure; and

The first exposure margin is determined as a sum of the second exposure margin and the available exposure margin.

The method of claim 10 , wherein the third exposure margin assigned to the first radio is less than or equal to one.

12. The method of claim 8, wherein determining the first allowable transmit power further comprises determining the first allowable transmit power as a product of the first exposure margin and the second maximum time-averaged transmit power level.

13. The method according to claim 8, further comprising:

determining a second exposure margin associated with a third radio for a third time interval based on the first exposure margin and a second exposure associated with the second radio for a second transmission in the second time interval;

determining a second allowable transmit power associated with the third radio for the third time interval based on the second exposure margin and a second maximum time-averaged transmit power level associated with the third radio; and

A second signal is transmitted at a second transmit power within the third time interval using the third radio based on the second allowable transmit power.

14. The method of claim 13, wherein determining the second exposure margin comprises:

determining a third exposure margin for the third radio as a difference between one and a sum of: a minimum exposure margin assigned to the first radio and a minimum exposure margin assigned to the second radio;

determining an available exposure margin as a difference between the first exposure margin allocated to the second radio and the second exposure; and

The second exposure margin is determined as a sum of the third exposure margin for the third radio and the available exposure margin.

The method of claim 13 , wherein the third time interval has the same duration as the second time interval.

16. The method according to claim 13, further comprising:

transmitting, using the first radio, a third signal during the third time interval; and

A fourth signal is transmitted using the second radio in the third time interval, wherein the third time interval is adjacent in time to the second time interval, and wherein the second time interval is between in time the first time interval and the third time interval.

17. The method of claim 13, wherein determining the second allowable transmit power comprises determining the second allowable transmit power further based on a duty cycle associated with the third radio.

18. The method of claim 13, wherein determining the second allowable transmit power comprises determining the second allowable transmit power further based on a second power limit applied to the second radio.

19. The method of claim 1, wherein determining the first allowable transmit power comprises determining the first allowable transmit power further based on a first power limit applied to the first radio.

20. The method of claim 1, further comprising determining a second allowable transmit power associated with a third radio, the third radio being associated with a first antenna group, wherein the first radio and the second radio are associated with a second antenna group.

21. The method of claim 20, wherein the determination of the second allowable transmit power is independent of transmissions associated with the second antenna group.

22. The method of claim 1, further comprising transmitting a second signal using the first radio in a sub-6 GHz frequency band, wherein transmitting the first signal comprises transmitting the first signal using the second radio in a mmWave frequency band.

23. The method of claim 1, further comprising selecting the first radio among the radios based on one or more priorities associated with a plurality of radios.

24. An apparatus for wireless communication, the apparatus comprising:

one or more memories that collectively store executable instructions; and

one or more processors, the one or more processors coupled to the one or more memories, the one or more processors being collectively configured to execute the executable instructions to cause the apparatus to:

Transmission of a first signal at a first transmission power within the second time interval using the second radio is controlled based on the first allowable transmission power.

25. The apparatus of claim 24, wherein:

To determine the first exposure, the one or more processors are collectively configured to execute the executable instructions to cause the apparatus to determine the first exposure based at least in part on a first maximum time-averaged transmit power level associated with the first radio; and

To determine the first allowable transmit power, the one or more processors are collectively configured to execute the executable instructions to cause the apparatus to determine the first allowable transmit power further based on a second maximum time-averaged transmit power level associated with the second radio.

26. The apparatus of claim 24, wherein:

The one or more processors are further collectively configured to execute the executable instructions to cause the apparatus to transmit a second signal at a second transmit power during the second time interval using the first radio;

the first radio has a higher transmit priority than the second radio; and

The second time interval is adjacent in time to the first time interval.

27. The apparatus of claim 26, wherein:

28. The apparatus of claim 27, wherein the one or more processors are further collectively configured to execute the executable instructions to cause the apparatus to determine the second allowable transmit power based on a duty cycle associated with the first radio.

29. An apparatus for wireless communication, the apparatus comprising:

means for determining a first exposure associated with a first radio used for a first transmission in a first time interval;

means for determining a first allowable transmit power associated with a second radio for a second time interval based at least in part on the first exposure associated with the first radio; and

Means for transmitting a first signal at a first transmit power within the second time interval using the second radio based on the first allowable transmit power.

30. A non-transitory computer-readable medium having instructions stored thereon that, when executed by a device, cause the device to perform operations comprising: