WO2019006747A1

WO2019006747A1 - Method and apparatus for sounding signal decoding

Info

Publication number: WO2019006747A1
Application number: PCT/CN2017/092240
Authority: WO
Inventors: Ning Wei; Kaiying Lv; Bo Sun
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2017-07-07
Filing date: 2017-07-07
Publication date: 2019-01-10
Anticipated expiration: 2020-01-07

Abstract

L'invention concerne un procédé et un système permettant de déterminer des valeurs de paramètre pour de multiples débits de données de récepteur à partir d'une seule séquence de sondage de réveil. Dans un mode de réalisation donné à titre d'exemple, un procédé mis en œuvre par un premier nœud de communication consiste à : recevoir un signal de sondage codé à un débit de données de transmission; effectuer un premier décodage sur la base du signal de sondage, le premier décodage étant basé sur une première période de mesure du signal de sondage correspondant à un premier débit de données qui est différent du débit de données de transmission; et déterminer une première valeur de paramètre sur la base du premier décodage.A method and system for determining parameter values for multiple receiver data rates from a single wake-up polling sequence. In an exemplary embodiment, a method implemented by a first communication node includes: receiving a coded probing signal at a transmission data rate; performing a first decoding on the basis of the probing signal, the first decoding being based on a first measurement period of the sounding signal corresponding to a first data rate which is different from the transmission data rate; and determining a first parameter value based on the first decoding.

Description

METHOD AND APPARATUS FOR SOUNDING SIGNAL DECODING

TECHNICAL FIELD

The disclosure relates generally to wireless communications and, more particularly, to systems, methods and devices for determining parameter values for multiple receiver data rates from a single wake up sounding sequence.

BACKGROUND

As the Internet of things (IoT) becomes a reality, a large number of IoT devices will require access to one or more communication networks, connected to each other through wired or wireless means. The IoT is expected to offer advanced connectivity of devices, systems, and services that go beyond machine-to-machine (M2M) communications and will implement a variety of protocols, domains, and applications. The interconnection of communication-enabled devices (i.e., “smart objects” ) is expected to usher in automation in a wider variety of fields, such as intelligent transportation, environmental protection, public security, smart Home, industrial monitoring, personal health, etc., while also enabling advanced applications like a smart grid, and smart cities. It is estimated that the IoT will consist of almost 50 billion interconnected things (i.e., communication-enabled objects) by 2020.

In a wireless communication network, such as a wireless local area network (WLAN) , wireless communication nodes such as access points and stations can become IoT devices. An access point (AP) is the basic equipment in a wireless LAN that establishes a Basic Service Set (BSS) , and a station (STA) typically establishes wireless communications with the AP through a predetermined association or registration procedure, and thereafter communicates with the AP for data transmission. In some embodiments, an AP may also be equivalent to a base station (BS) and a STA be equivalent to a user equipment (UE) . In some types of networks such as ad-hoc networks, for example, an AP is typically not present in the network, and STA’s can communicate directly with each other and other nodes. Therefore, for both independent BSS (IBSS) and BSS, both STA’s and AP’s can generally be referred to as wireless communication nodes, or simply communication nodes, herein.

In a WLAN, for example, STAs can be IoT devices such as sensors equipped with wireless communication modules. It is anticipated that a majority of IoT devices will be battery-powered and installed at locations that may be difficult or expensive to maintain or access on a frequent basis. Thus, it is desirable for such devices to maximize their battery life. To achieve this purpose, when the STA is in the absence of traffic for a certain period of time, the STA enters power saving mode and stays in sleep mode until an AP requests communication with the STA. Typically, in resuming communications, the STA and AP may resume communication in the manner previously conducted, such as the data rate that an STA and AP utilized prior to entering the power saving sleep mode.

SUMMARY OF THE INVENTION

The exemplary embodiments disclosed herein are directed to solving the issues relating to one or more of the problems presented in the prior art, as well as providing additional features that will become readily apparent by reference to the following detailed description when taken in conjunction with the accompany drawings. In accordance with various embodiments, exemplary systems, methods, devices and computer program products are disclosed herein. It is understood, however, that these embodiments are presented by way of example and not limitation, and it will be apparent to those of ordinary skill in the art who read the present disclosure that various modifications to the disclosed embodiments can be made while still remaining within the scope of the invention.

In accordance with one exemplary embodiment, a method performed by a first communication node includes: receiving a sounding signal encoded at a transmission data rate； performing a first decoding based on the sounding signal, wherein the first decoding is based on a first measurement period of the sounding signal corresponding to a first data rate that is different with the transmission data rate； and determining a first parameter value based on the first decoding.

In another embodiment, a first communication node includes: a receiver configured to receive a sounding signal encoded at a transmission data rate； at least one processor coupled to the receiver, the at least one processor configured to: perform a first decoding based on the sounding signal, wherein the first decoding is based on a first measurement period of the sounding signal corresponding to a first data rate that is different with the transmission data rate； and determine a first parameter value based on the first decoding.

In yet another embodiment, a method performed by a second communication node includes: sending a sounding signal at a transmission data rate； receiving a feedback signal, the feedback signal based on a first decoding of the sounding signal corresponding to a first data rate that is different with the transmission data rate； selecting a further transmission data rate based on the feedback signal； and sending a bit stream at the further transmission data rate.

In a further embodiment, second communication node includes: a transmitter configured to: send a sounding signal at a transmission data rate； a receiver configured to: receive a feedback signal, the feedback signal based on a first decoding of the sounding signal corresponding to a first data rate that is different with the transmission data rate； and at least one processor coupled to the receiver and the transmitter, the at least one processor configured to: select a further transmission data rate based on the feedback signal, wherein the receiver is configured to send a bit stream at the further transmission data rate.

BRIEF DESCRIPTION OF THE DRAWINGS

Various exemplary embodiments of the invention are described in detail below with reference to the following Figures. The drawings are provided for purposes of illustration only and merely depict exemplary embodiments of the invention. These drawings are provided to facilitate the reader's understanding of the invention and should not be considered limiting of the breadth, scope, or applicability of the invention. It should be noted that for clarity and ease of illustration these drawings are not necessarily drawn to scale.

Figure 1 illustrates a block diagram of an exemplary communication network environment in which the present invention can be practiced, in accordance with some embodiments of the invention.

Figure 2 illustrates a block diagram of an access point, in accordance with some embodiments of the invention.

Figure 3 illustrates a block diagram of a station, in accordance with some embodiments of the invention.

Figure 4 illustrates a data structure for a wake up sounding packet, in accordance with some embodiments of the invention.

Figure 5 illustrates features of multiple data rate inference analysis on a sounding sequence with waveform coding, in accordance with some embodiments of the invention.

Figure 6 illustrates features of multiple data rate inference analysis on a sounding sequence without waveform coding, in accordance with some embodiments of the invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Various exemplary embodiments of the invention are described below with reference to the accompanying figures to enable a person of ordinary skill in the art to make and use the invention. As would be apparent to those of ordinary skill in the art, after reading the present disclosure, various changes or modifications to the examples described herein can be made without departing from the scope of the invention. Thus, the present invention is not limited to the exemplary embodiments and applications described and illustrated herein. Additionally, the specific order or hierarchy of steps in the methods disclosed herein are merely exemplary approaches. Based upon design preferences, the specific order or hierarchy of steps of the disclosed methods or processes can be rearranged while remaining within the scope of the present invention. Thus, those of ordinary skill in the art will understand that the methods and techniques disclosed herein present various steps or acts in a sample order, and the invention is not limited to the specific order or hierarchy presented unless expressly stated otherwise.

Figure 1 illustrates an exemplary wireless environment in which one or more embodiments of the invention can be practiced. As shown in Figure 1, a wireless local area network (WLAN) 100 includes at least one access point (AP) 102 and a plurality of stations (STA’s ) 104a, 104b, 104c and 104d, which are communicatively coupled to the AP 102. Although various aspects of the invention are described herein in the context of a WLAN environment, it is understood that the invention may be practiced in any communication environment in which two or more nodes can communicate with each other when at least one of the nodes is operating in a duty cycle power saving mode. Examples of such alternative environments include a wide area network (WAN) , metropolitan area network (MAN) , local area network (LAN) , a neighborhood aware network (NAN) , and a personal area network (PAN) . Networks also differ according to the switching/routing technique used to interconnect the various network nodes and devices (e.g. circuit switching vs. packet switching) , the type of physical media employed for transmission (e.g. wired vs. wireless) , and the set of communication protocols used (e.g., Internet protocol suite, SONET (Synchronous Optical Networking) , Ethernet, etc. ) .

Referring again to the exemplary environment of Figure 1, a WLAN 100 can be used to interconnect nearby devices employing known networking protocols. However, various embodiments can employ any communication standard to transmit data between two or more nodes. In some embodiments, the AP 102 can serve as a hub or base station for the WLAN 100 and the STA’s 104a –104d can be various types of devices capable of operating in a power-saving mode and having a communication module. For ease of discussion, when referring to any one of STA’s 104a-104d, the singular term “STA 104” will be used herein. Examples of STA 104 include devices that include a communication module capable of operating in a power saving mode, and further include any one of various sensors that can measure any operational or environmental parameter (e.g., temperature, pressure, motion, speed, acceleration, ambient light, proximity, voltage, current, image/camera, etc. ) . In alternative embodiments, the STA 104 can be a laptop computer, a personal digital assistant (PDA) , a mobile phone, etc. In some embodiments, the STA 104 can establish a communication link with the AP 102 via a Wi-Fi protocol (e.g., IEEE 802.11 protocol) to obtain connectivity to the Internet or other networks. In some embodiments, the STA 104 can also perform some or all of the functions of the AP 102 and communication with other STA’s when employed in an ad-hoc network, for example.

In various embodiments, the AP 102 can include, or be implemented as, a NodeB, Radio Network Controller ( "RNC" ) , eNodeB, Base Station Controller ( "BSC" ) , Base Transceiver Station ( "BTS" ) , Base Station ( "BS" ) , Transceiver Function ( "TF" ) , Radio Router, Radio Transceiver, or some other communication node configured to perform the synchronization functions described herein. The term “configured for” or “configured to” as used herein with respect to a specified operation or function refers to a device, component, circuit, structure, machine, etc. that is physically constructed, programmed and/or arranged to perform the specified operation or function.

Various processes and methods can be used for transmissions in the wireless communication network 100 between the AP 102 and the STA 104, and between two STA’s 104a and 104b, for example. For example, signals can be sent and received in accordance with orthogonal frequency division multiplexing (OFDM) /orthogonal frequency division multiple access (OFDMA) techniques, or code division multiple access (CDMA) techniques.

Figure 2 illustrates a block diagram of the AP 102, in accordance with some embodiments. The AP 102 is an example of a device that can be configured to implement the various methods described herein. The AP 102 includes a housing 200 containing a system clock 201, a processor 203, a memory 205, a transceiver 406 comprising a transmitter 207 and receiver 209, a signal detector 211, and a power module 213.

The system clock 201 provides the timing signals to the processor 203 for controlling the timing of all operations of the AP 102. The processor 203 controls the general operation of the AP 102 and can include one or more processing circuits or modules such as a central processing unit (CPU) and/or any combination of general-purpose microprocessors, microcontrollers, digital signal processors (DSPs) , field programmable gate array (FPGAs) , programmable logic devices (PLDs) , controllers, state machines, gated logic, discrete hardware components, dedicated hardware finite state machines, or any other suitable circuits, devices and/or structures that can perform calculations or other manipulations of data. As described in further detail below, the processor 203 also controls and executes a multiple data rate inference analysis to enable the AP 102 to synchronize (e.g., communicate in accordance with) a further transmission data rate with a STA 104, in accordance with various embodiments of the invention.

The memory 205, which can include both read-only memory (ROM) and random access memory (RAM) , can provide instructions and data to the processor 203. A portion of the memory 205 can also include non-volatile random access memory (NVRAM) . The processor 203 typically performs logical and arithmetic operations based on program instructions stored within the memory 205. The instructions (a. k. a., software) stored in the memory 205 can be executed by the processor 203 to perform the methods described herein. The processor 203 and memory 205 together form a processing system that stores and executes software. As used herein, “software” means any type of instructions, whether referred to as software, firmware, middleware, microcode, etc. which can configure a machine or device to perform one or more desired functions or processes. Instructions can include code (e.g., in source code format, binary code format, executable code format, or any other suitable format of code) . The instructions, when executed by the one or more processors, cause the processing system to perform the various functions described herein.

The transceiver 206, which includes the transmitter 207 and receiver 209, allows the AP 102 to transmit and receive data to and from a remote device (e.g, STA 104) . An antenna 210 is typically attached to the housing 200 and electrically coupled to the transceiver 206. In various embodiments, the AP 102 include (not shown) multiple transmitters, multiple receivers, multiple transceivers, and/or multiple antennas. The transmitter 207 can be configured to wirelessly transmit packets having different packet types or functions, such packets being generated by the processor 203. Similarly, the receiver 209 is configured to receive packets having different packet types or functions, and the processor 203 is configured to process packets of a plurality of different packet types. For example, the processor 203 can be configured to determine the type of packet and to process the packet and/or fields of the packet accordingly.

In accordance with some embodiments, the AP 102 can also include the signal detector 211, which can be used to detect and quantify the level of signals received by the transceiver 206. The signal detector 211 can detect and quantify such parameters as total energy, energy per subcarrier per symbol, power spectral density and other signals. The power module 213 can include a power source such as one or more batteries, and a power regulator, to provide regulated power to each of the above-described

modules

203, 205, 206 (207 and 209) and 211. In some embodiments, if the AP 102 is coupled to a dedicated external power source (e.g., a wall electrical outlet) , the power module 213 can include a transformer and a power regulator.

The various modules discussed above are coupled together by a bus system 215. The bus system 215 can include a data bus and, for example, a power bus, a control signal bus, and/or a status signal bus in addition to the data bus. It is understood that the modules of the AP 102 can be operatively coupled to one another using any suitable techniques and mediums.

Although a number of separate modules or components are illustrated in Figure 2, persons of ordinary skill in the art will understand that one or more of the modules can be combined or commonly implemented. For example, the processor 203 can implement not only the functionality described above with respect to the processor 203, but also implement the functionality described above with respect to the signal detector 211. Conversely, each of the modules illustrated in Figure 2 can be implemented using a plurality of separate components or elements.

Figure 3 illustrates a block diagram of the STA 104, in accordance with some embodiments of the invention. As shown in Figure 3, the STA 104 can include a housing 300, which contains a system clock 301, a processor 303, a memory 305, a transceiver 306 comprising a transmitter 307 and a receiver 309, an antenna 310, a signal detector 311, a power module 313, and a system bus 315. Each of these components or modules can be similar or identical to the respective

corresponding components

201, 203, 205, 206, 207, 209, 210, 211, 213 and 215 discussed above with respect to the AP 102 shown in Figure 2. Therefore, for the sake of brevity, descriptions of these components or modules are not repeated.

As shown in Figure 3, in accordance with some embodiments, the STA 104 can further include one or more sensors 317, a wake up receiver (WUR) 319 and a WUR timing module 321, which are operatively coupled to one another and the other modules discussed above via the system bus 315. The one or more sensors 317 can include any desired sensor for sensing any one or more desired operational or environmental parameters such as pressure, temperature, moisture, speed, acceleration, distance traveled, power, voltage, current, etc. Upon sensing such operational or environmental parameters, the STA 104 can communicate measured operational or environmental parameter values to the AP 102, which can then relay them via the internet, for example, to a central server or system for further processing and or action based on the measured operational or environmental parameter values. In this way, the STA 104 can be one of a multitude of devices or nodes that can be coupled to one another and/or a central server or system via the Internet to implement an IoT application, as discussed above.

The WUR 319 is an additional receiver besides the main receiver 309, whose task is to wake up the main transceiver 306, and any other modules such as

modules

303, 305, 311, 313, 317, shown in Figure 3 that may be asleep, when there is a request for communication from another node (e.g., AP 102) in the wireless network 100. The WUR 319 is coupled to the antenna 310 and periodically wakes up during a predetermined during of time (i.e., defined by a wake up window) to check for a signal transmitted by the AP 102 during pre-negotiated wake up windows. Thus, the WUR 319 allows the main transceiver 306 and some or all of the

other modules

303, 305, 311, 313, 317, to stay in a sleep mode (e.g., powered down or reduced power mode) when the STA 104 is idle (i.e., does not need to transmit or receive data to or from another node) . Additionally, the WUR 319 requires less power than the main transceiver 306 when they are performing their respective operations. In this way, the WUR 319 enables conservation of power expended by the STA 104. To further conserve power and/or prolong battery life, if the power module 313 comprises a battery power source, the WUR 319 can operate in a duty cycle power-saving mode, as described above.

The WUR timing module 321 is coupled to the system clock 301 and controls the duty cycle power-saving operation of the WUR 319. The WUR timing module 321 wakes up the WUR 319 at the beginning of each negotiated wake up window 101 (Fig. 1) and thereafter commands the WUR 319 to resume sleep mode (e.g., powered down or reduced power mode) at the end of each wake up window 101, repeating this sequence at the beginning of each negotiated wake up window. In some embodiments, the WUR timing module 321 may be integrated as part of the processor 303. In alternative embodiments, the WUR timing module may be a separate processing module that performs wake up window adjustments, as described in further detail below, while the main processor 303 and transceiver 306 remain in sleep mode. Thus, the WUR timing module 321 enables the STA 104 to perform wake up window timing adjustments so that the wake up windows of the STA 104 can be synchronized with the wake up windows of the AP 102.

As discussed above, in order to conserve power (e.g., battery power) two or more nodes of a network (e.g., an STA and AP) can employ a WUR to synchronously communicate with each other in accordance with negotiated wake up window start times, durations and intervals. In other words, the nodes can periodically wake from a sleep state to periodically transmit and/or receive synchronization messages and discovery messages. The WUR may be deployed at an STA and may reduce power consumption when the STA is in a standby (e.g., sleep) mode, where no information is transmitted or received from the STA. The WUR may be an independent companion radio to a main, or primary, radio (e.g., the transceiver 306) of an STA and may expend less power to operate relative to the main, or primary, radio. Accordingly, during the sleep mode, the WLAN device may power off its main radio and enable a WUR to wait for a wake up order from access point (AP) . The wake up order may be transmitted as a wake up packet. Once the wake up packet from AP is received, the STA will turn on the main radio to begin communicating with the AP. For example, the AP 102 may send wake up orders to the STA 104 within negotiated wake up windows. The WUR module 319 of the STA 104 may wake up at the start of the negotiated wake up window to receive the wake up order from the AP 102.

Traditionally in a WLAN system, a wake up packet includes a legacy preamble, wake up preamble and wake up payload. However, different than traditional WLAN systems, systems and methods in accordance with various embodiments may include a wake up sounding packet, in lieu of a traditional wake up packet, for which multiple data rate inference analysis may be performed.

Figure 4 illustrates a data structure for a wake up sounding packet 400, in accordance with some embodiments of the invention. The wake up sounding packet 400 may include a legacy preamble 402, a wake up preamble 404, and a wake up sounding sequence 406 (e.g., a wake up sounding signal or a sounding signal) . Accordingly, the wake up sounding packet 400 may differ from a traditional wake up packet at least by including the wake up sounding sequence 406. The wake up sounding packet 400 may begin with the legacy preamble 402 that may be decoded by legacy STAs (i.e., existing STAs at the time of filing of the present application) . These legacy STAs may be compliant, for example, with the 802.11a, 802.11ac, 802.11ax, etc. standards. The legacy preamble 402, for example, informs the legacy STA’s how long the wake up sounding packet 400 will occupy the medium. The legacy preamble 402 may also include a Legacy Short Training Field (LSTF) , Legacy Long Training Field (LLTF) , and Legacy Signal field (LSIG) . Optionally, the legacy preamble may include an extra OFDM symbol modulated by binary phase shift keying (BPSK) . The wake up preamble 404 may include the wake up order and inform the STA that a wake up sounding sequence 406 follows the wake up preamble 404. In certain embodiments, a wake up preamble may also include an indication of a transmission data rate for the wake up sounding sequence 406, as discussed further below.

The wake up sounding sequence 406 may follow the wake up preamble 404. Multiple data rate inference analysis may be performed based on the wake up sounding sequence 406. The wake up sounding sequence 406 may be an information signal (e.g., a radio signal with encoded information) at a single transmission data rate. From the wake up sounding sequence 406, different information may be decoded when the wake up sounding sequence 406 is analyzed at different reception data rates, as will be discussed further below. Stated another way, the wake up sounding sequence 406 may be a single, coded signal from which parameter values for multiple data rates may be determined. These parameter values may evaluate how well the wake up sounding sequence 406 is received if decoded at different data rates. These parameter values may be based on a comparison between the transmitted wake up sounding sequence 406 received by the STA and a locally stored version of the transmitted wake up sounding sequence 406 at the STA, which may serve as a reference for the transmitted wake up sounding sequence 406. For example, the parameter values may reflect an AP’s decoding of various sounding symbols (e.g., OFDM symbols) in the wake up sounding sequence 406 when decoding is performed at different data rates (e.g., reception data rates) . Examples of these parameter values will be discussed further below and may include a packet error rate (PER) , a bit error rate (BER) , power threshold, and the like.

A data rate for further transmission (also termed as a further transmission data rate) may be selected based on the parameter values for different reception data rates decoded from the wake up sounding sequence 406. This selection may be based upon the parameter values meeting a criterion (e.g., a threshold) or may be based upon a comparison among the parameter values for a best parameter value (e.g., a parameter value of a greater or least value) . That further transmission data rate may be indicated (e.g., sent as a feedback signal or an indicator signal) from the STA to the AP that sent the wake up sounding sequence 406 so that the AP may communicate with the STA using the further transmission data rate. Accordingly, the AP and STA may synchronize to communicate at the further transmission data rate. In certain embodiments, no further transmission data rate may be selected and the STA may continue in sleep mode and not communicate with the AP. In certain embodiments, no further transmission data rate may be selected and an indicator of no selection of any further transmission data rate (e.g., a further transmission data rate of a null value) may be indicated (e.g., sent as a feedback signal) from the STA to the AP that sent the sounding sequence 406.

Accordingly, parameter values at different reception rates may be evaluated based on a single wake up sounding sequence 406. A most suitable one (e.g., best) of the reception data rates may be selected for further communication between an AP and STA (e.g., selected to be the further transmission data rate) , rather than merely working with the original transmission data rate of the wake up sounding sequence 406. This most suitable one of the reception data rates (e.g., further transmission data rate) may be selected based upon factors (e.g., criteria) such as to maximize data rate while maintaining acceptable parameter values (e.g., PER, BER) . Also, by performing multiple data rate inference analysis, the further transmission data rate may be higher (e.g., greater) than the transmission data rate (e.g., where more data may be encoded per unit time) while maintaining acceptable parameter values.

In various embodiments, the wake up sounding sequence 406 may utilize a combination of OFDM and OOK (on-off keying) to modulate information encoded in the wake up sounding sequence 406 as information bits. For example, an OFDM symbol may be transmitted during an interval to indicate an “on” state, to contrast with an “off” state in which nothing is sent during the interval. Also, single or joint states may be used to represent binary values of “1” and “0. ” For example, the “on” state may indicate a binary value of “1” and the “off” state may represent a binary value of ‘0’ . Also, for Manchester coding (e.g., waveform coding) , “on-off” and “off-on” transitions may indicate binary values of “1” and “0” respectfully. Accordingly, a data rate of a wake up sounding sequence 406 modulated by a combination of OFDM and OOK may depend on the symbol duration (e.g., measurement period) associated with “on” and “off” states, which may be reflective of a binary values of “1” and “0. ” Accordingly, the shorter the symbol duration (e.g., measurement period) , the larger the data rate (e.g., more information transmitted per unit time) . Also, the shorter the symbol duration (e.g., measurement period) , the smaller the data rate (e.g., less information transmitted per unit time) .

As used herein, the term waveform coding may be synonymous with a type of Manchester coding. Although Manchester coding, or waveform coding is a term discussed explicitly here, different types of coding may be performed in accordance with different embodiments as desired for different applications. For example, non-waveform (e.g., non-Manchester) coding may include unipolar coding (e.g., where a positive voltage represents a binary 1 and zero volts indicates a binary 0) or polar coding (e.g., where a binary 1 is represented by a significant condition, such as a positive voltage, and a binary 0 is represented by another significant condition, such as a negative voltage) .

Accordingly, in certain embodiments, wake up sounding sequence 406 may include both “on” symbols and “off” symbols (e.g., intervals or periods in which a signal energy is or is not transmitted) . Each, or a combination (e.g., transition) , of the “on” symbols or “off” symbols may represent binary values of “1” or “0. ” For example, in embodiments where the wake up sounding sequence 406 encodes information without waveform coding (e.g., without Manchester coding) , the information bit stream carried by the wake up sounding sequence 406 may be “10101010…” when at the transmission data rate. Also, in embodiments where the wake up sounding sequence 406 encodes information with waveform coding (e.g., with Manchester coding) the information bit stream carried by the wake up sounding sequence 406 may be “1111111…” , or “0000000…” when at the transmission data rate. The duration of each symbol (e.g., “0” or “1” binary values) may be identical and may be 1 microsecond (us) , 2us, 4us, 8us, 16us, etc. as will be discussed further below.

As discussed above, multiple data rate inference analysis may be performed based on decoding the wake up sounding sequence 406 at different reception data rates. At least some of these reception data rates may be different than (e.g., greater than) the transmission data rate at which information is encoded in the wake up sounding sequence 406. These reception data rates may be determined by decoding the wake up sounding sequence 406 at different data rates. For example, these reception data rates may be determined by truncating a measurement period which defines a single symbol (e.g., “0” or “1” binary values) at a transmission data rate into multiple symbols (e.g., multiple “0” or “1” binary values) at reception data rates that are greater than the transmission data rate. As discussed above, the “on” or “off” symbols may be determined as OFDM symbols with or without energy and may translate into “0” or “1” binary values depending on the coding scheme (e.g., waveform or non-waveform coding) . Also, as discussed above, parameter values may be determined at each of the reception data rates to evaluate the quality of signal reception at the various reception data rates.

Figure 5 illustrates features of multiple data rate inference analysis on a wake up sounding sequence 502 with waveform coding, in accordance with some embodiments of the invention. The wake up sounding sequence 502 is plotted with time on the x axis and voltage on the y axis. As shown in Figure 5, during a first time period from 0 to 8 microseconds (denoted as 0 to 8 μs) , the sounding sequence 502 is a time variant signal (i.e., electromagnetic energy is provided by the signal) . During a second time period from 8 to 16 μs, the sounding sequence 502 is a flat signal with zero electromagnetic energy. The wake up sounding sequence 502 may be encoded with waveform coding (e.g., Manchester coding) where an “on-off” transition denotes a binary bit value of “1” and an “off-on” transition denotes a binary bit value of “0” to provide with a data signal of “1111, ” as shown in Figure 5. The duration of each “on” state (i.e., “1” state) may be 16 us, corresponding to the transmission data rate of 62.5 kbps of the sounding sequence 502. Also, the measurement period for a transmission data rate (e.g., transmission data rate measurement period 504) may be 16 us. Accordingly, the transmission data rate may be 62.5 kilobits per second (kbps) , calculated as 1 bit/ [ (8+8) us/1s] ＝ 62.5kbps.

Also, multiple data rate inference analysis may be performed based on decoding the wake up sounding sequence 406 at reception data rates which may be different (e.g., greater) than the transmission data rate. These reception data rates may include measurement periods that are shorter than a measurement period for the transmission data rate. For example, a reception data rate of 125kbps (which is greater than the transmission data rate of 62.5kbps) may have a measurement period of 8 us (e.g., reception data rate measurement period 506) . An information bit stream at this reception data rate may be determined by truncating symbols (e.g., the binary values of “1” or “0” ) of the wake up sounding sequence 502 into shorter symbols at time intervals of: [4us, 12us] , [12us, 20us] , [20us, 28us] , [28us, 36us] , [36us, 44us] , [44us, 52us] , [52us, 60us] , and so on. For clarity, these time intervals are also illustrated as the time intervals between the lines noted respectively as A1-A1, A2-A3, A3-A4, A4-A5, A5-A6, A6-A7, A7-A8 and so on. Accordingly, the corresponding information bit stream of the wake up sounding sequence 406 may be “1010101” at a reception data rate of 125kbps.

As another example, a reception data rate of 250kbps may have a measurement period of 4 us (e.g., with reception data rate measurement period 508) . An information bit stream at this reception data rate of 250kbps may be determined by truncating the symbols (e.g., the binary values of “1” or “0” ) of wake up sounding sequence 502 into shorter symbols at time intervals of [6us, 10us] , [14us, 18us] , [22us, 26us] , [30us, 34us] , [38us, 42us] , [46us, 50us] , [54us, 58us] and so on. For clarity, these time intervals are also illustrated as the time intervals between the lines noted respectively as B1-B2, B3-B4, B5-B6, B7-B8, B9-B10, B11-B12, B13-B14 and so on. Information outside of these time intervals may be termed as gaps and be disregarded as they may be outside of the time intervals of interest for this reception data rate and thus may not carry meaningful information for the sounding sequence 502 at this reception data rate. Stated another way, the time intervals for this reception data rate may have a time (or phase) offset from where each of the time intervals may skip over gaps that are outside of the time intervals of interest. Accordingly, the corresponding information bit stream of the wake up sounding sequence 406 may be “1010101’ ” at a reception data rate of 250kbps.

Even higher reception data rates with even shorter reception data rate measurement periods may be contemplated with different applications in accordance with various embodiments. For example, higher reception data rates may be contemplated with reception data rate measurement periods of 2 us or 1 us.

Figure 6 illustrates features of multiple data rate inference analysis on a wake up sounding sequence 602 without waveform coding, in accordance with some embodiments of the invention. As discussed above, non-waveform (e.g., non-Manchester) coding may include unipolar coding (e.g., where a positive voltage represents a binary 1 and zero volts indicates a binary 0) or polar coding (e.g., where a binary 1 is represented by a significant condition, such as a positive voltage, and a binary 0 is represented by another significant condition, such as a negative voltage) . The wake up sounding sequence 602 is plotted with time on the x axis and voltage along the y axis. As shown in Figure 6, during a first time period from 0 to 16 μs, the sounding sequence 602 is a time variant signal (i.e., electromagnetic energy is provided by the signal) . During a second time period from 16 to 32 μs, the sounding sequence 602 is a flat signal with zero electromagnetic energy. The wake up sounding sequence 602 is not encoded with waveform coding (e.g., without Manchester coding) with a data signal of “1010” , where an “on” denotes a binary bit value of “1” and “off” denotes a binary bit value of “0. ” The duration of the “on” and “off” symbols may each be 16us and be equivalent to a measurement period for a transmission data rate (e.g., transmission data rate measurement period 604) . Accordingly, the transmission data rate may be 62.5 kilobits per second (kbps) , calculated as 1bit/ [16us/1s] ＝62.5kbps.

Also, multiple data rate inference analysis may be performed based on decoding the wake up sounding sequence 602 at reception data rates which may be different (e.g., greater) than the transmission data rate. These reception data rates may include measurement periods that are shorter than a measurement period for the transmission data rate. For example, a reception data rate of 125kbps (which is greater than the transmission data rate of 62.5kbps) may have a measurement period of 8 us (e.g., reception data rate measurement period 606) . An information bit stream at this reception data rate may be determined by truncating symbols (e.g., the binary values of “1” or “0” ) of the wake up sounding sequence 602 into shorter symbols at time intervals of: [0us, 8us] , [8us, 16us] , [16us, 24us] , [24us, 32us] , [32us, 40us] , [40us, 48us] , [48us, 56us] , [56us, 64us] , and so on. For clarity, these time intervals are also illustrated as the time intervals between the lines noted respectively as A1-A1, A2-A3, A3-A4, A4-A5, A5-A6, A6-A7, A7-A8, A8-A9, and so on) . Accordingly, the corresponding information bit stream of the wake up sounding sequence 602 may be “11001100” at a reception data rate of 125kbps.

As another example, a reception data rate of 250kbps may have a measurement period of 4 us (e.g., with reception data rate measurement period 608) . An information bit stream at this reception data rate of 250kbps may be determined by truncating the symbols (e.g., the binary values of “1” or “0” ) of the wake up sounding sequence 602 into shorter symbols at time intervals of [0us, 4us] , [4us, 8us] , [8us, 12us] , [12us, 16us] , [16us, 20us] , [20us, 24us] , [24us, 28us] , [28us, 32us] , [32us, 36us] , [36us, 40us] , [40us, 44us] , [44us, 48us] , [48us, 52us] , [52us, 56us] , [56us, 58us] , [58us, 64us] , and so on. For clarity, these time intervals are also illustrated as the time intervals between the lines noted respectively as A1-B1, B1-A2, A2-B2, B2-A3, A3-B3, B3-A4, A4-B4, B4-A5, A5-B5, B5-A6, A6-B6, B6-A7, A7-B7, B7-A8, A8-B8, B8-A9 and so on. Accordingly, the corresponding information bit stream of the wake up sounding sequence 406 may be “1111000011110000” at a reception data rate of 250kbps. Furthermore, different than the sounding sequence 502 of Figure 5, the sounding sequence 602 of Figure 5 without waveform coding may not have information outside of the time intervals as the time intervals may be continuous without gaps. Accordingly, the sounding sequence 502 may pack more bits per unit time with data rates of 250 kbps or higher when performing multiple data rate inference analysis.

Parameter values for each of the reception data rates may be determined to evaluate how well the wake up sounding sequence is received when decoded at the different reception data rates. As discussed above, the wake up sounding sequence may be predetermined (e.g., the transmitted wake up sounding sequence may be determined prior to transmission by the AP and stored locally at the receiving STA) for the different reception data rates. Accordingly, these parameter values may be a comparison between the received wake up sounding sequence and the predetermined, reference wake up sounding sequence locally stored at the STA for each reception data rate. Stated another way, these parameter values may be based on a comparison between the transmitted wake up sounding sequence received by the STA and a locally stored version of the transmitted wake up sounding sequence at the STA, which may serve as a reference for the transmitted wake up sounding sequence.

For example, the parameter values may reflect an AP’s decoding of various sounding symbols in a wake up sounding sequence decoded at different reception data rates. Examples of these parameter values may include a packet error rate (PER) and a bit error rate (BER) and the like, which may be utilized to determine a data rate. A PER may be an amount of erroneous packets decoded relative to the total number of packets received in a wake up sounding sequence. A BER may be an amount of erroneous bits decoded relative to the total number of bits received in a wake up sounding sequence.

Beyond parameter values that may be used to determine a data rate for further transmission, other parameters values may be determined that characterize the time variant signal that may be used in communications between an AP and STA, such as a power threshold value. The power threshold may be a power level (e.g., value) above which a symbol is considered to be a “0” or a “1. ” The power threshold may be determined for multiple data rate inference analysis on a wake up sounding sequence without waveform coding, such as that discussed above in connection with Figure 6.

A data rate for further transmission (also termed as a further transmission data rate) may be selected based on the parameter values for different reception data rates decoded from the wake up sounding sequence. The further transmission data rate may be a most suitable one of the reception data rates selected based upon factors (e.g., criteria) such as to maximize data rate while maintaining acceptable parameter values (e.g., PER, BER) . The further transmission data rate may be indicated (e.g., sent in an information signal) from the STA to the AP that sent the wake up sounding sequence 406 so that the AP may communicate with the STA using the further transmission data rate. In certain embodiments, the further transmission data rate may be higher (e.g., greater) than the transmission data rate (e.g., where more data may be encoded per unit time) while maintaining acceptable parameter values.

Although multiple data rate inference analysis is described above in connection with a wake up sounding sequence, multiple data rate inference analysis may be performed based on any signal from which multiple reception data rates may be inferred for different applications in accordance with various embodiments. For example, multiple data rate inference analysis may be performed on sounding sequences that are not associated with a WUR in order to estimate how well an information signal may be received at an STA from an AP at different reception data rates and to configure a further transmission data rate accordingly.

While various embodiments of the invention have been described above, it should be understood that they have been presented by way of example only, and not by way of limitation. Likewise, the various diagrams may depict an example architectural or configuration, which are provided to enable persons of ordinary skill in the art to understand exemplary features and functions of the invention. Such persons would understand, however, that the invention is not restricted to the illustrated example architectures or configurations, but can be implemented using a variety of alternative architectures and configurations. Additionally, as would be understood by persons of ordinary skill in the art, one or more features of one embodiment can be combined with one or more features of another embodiment described herein. Thus, the breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments.

It is also understood that any reference to an element herein using a designation such as "first, " "second, " and so forth does not generally limit the quantity or order of those elements. Rather, these designations can be used herein as a convenient means of distinguishing between two or more elements or instances of an element. Thus, a reference to first and second elements does not mean that only two elements can be employed, or that the first element must precede the second element in some manner.

Additionally, a person having ordinary skill in the art would understand that information and signals can be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits and symbols, for example, which may be referenced in the above description can be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

A person of ordinary skill in the art would further appreciate that any of the various illustrative logical blocks, modules, processors, means, circuits, methods and functions described in connection with the aspects disclosed herein can be implemented by electronic hardware (e.g., a digital implementation, an analog implementation, or a combination of the two, which can be designed using source coding or some other technique) , various forms of program or design code incorporating instructions (which can be referred to herein, for convenience, as "software" or a "software module) , or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware, firmware or software, or a combination of these technique, depends upon the particular application and design constraints imposed on the overall system. Skilled artisans can implement the described functionality in various ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure.

Furthermore, a person of ordinary skill in the art would understand that various illustrative logical blocks, modules, devices, components and circuits described herein can be implemented within or performed by an integrated circuit (IC) that can include 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, or any combination thereof. The logical blocks, modules, and circuits can further include antennas and/or transceivers to communicate with various components within the network or within the device. A general purpose processor can be a microprocessor, but in the alternative, the processor can be any conventional processor, controller, or state machine. A processor can 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 suitable configuration to perform the functions described herein.

If implemented in software, the functions can be stored as one or more instructions or code on a computer-readable medium. Thus, the steps of a method or algorithm disclosed herein can be implemented as software stored on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that can be enabled to transfer a computer program or code from one place to another. A storage media can be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer.

In this document, the term "module" as used herein, refers to software, firmware, hardware, and any combination of these elements for performing the associated functions described herein. Additionally, for purpose of discussion, the various modules are described as discrete modules； however, as would be apparent to one of ordinary skill in the art, two or more modules may be combined to form a single module that performs the associated functions according embodiments of the invention.

Additionally, memory or other storage, as well as communication components, may be employed in embodiments of the invention. It will be appreciated that, for clarity purposes, the above description has described embodiments of the invention with reference to different functional units and processors. However, it will be apparent that any suitable distribution of functionality between different functional units, processing logic elements or domains may be used without detracting from the invention. For example, functionality illustrated to be performed by separate processing logic elements, or controllers, may be performed by the same processing logic element, or controller. Hence, references to specific functional units are only references to a suitable means for providing the described functionality, rather than indicative of a strict logical or physical structure or organization.

Various modifications to the implementations described in this disclosure will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other implementations without departing from the scope of this disclosure. Thus, the disclosure is not intended to be limited to the implementations shown herein, but is to be accorded the widest scope consistent with the novel features and principles disclosed herein, as recited in the claims below.

Claims

A method performed by a first communication node， comprising：

receiving a sounding signal encoded at a transmission data rate；

performing a first decoding based on the sounding signal， wherein the first decoding is based on a first measurement period of the sounding signal corresponding to a first data rate that is different than the transmission data rate； and

determining a first parameter value based on the first decoding.
The method of claim 1， wherein the first data rate is greater than the transmission data rate.
The method of claim 1， further comprising：

determining whether the first parameter value meets a criterion； and

sending an indicator of the first data rate to a second communication node， wherein the sounding signal is received from the second communication node.
The method of claim 1， further comprising：

performing a second decoding based on the sounding signal， wherein the second decoding is based on a second measurement period of the sounding signal corresponding to a second data rate， the second measurement period being shorter than the first measurement period； and

determining a second parameter value based on the second decoding.
The method of claim 4， further comprising：

comparing the first and second parameter values with a predetermined threshold； and

determining， based on the comparing， to send an indicator of a null rate to a second communication node， wherein the sounding signal is received from the second communication node.
The method of claim 4， further comprising：

comparing the first parameter value with the second parameter value； and

determining， based on the comparing， either the first data rate or the second data rate for further communications with a second communication node， wherein the sounding signal is received from the second communication node.
The method of claim 6， further comprising：

sending an indicator of the determined data rate to the second communication node； and

receiving a bit stream from the second communication node at the determined data rate.
The method of claim 1， wherein the first communication node comprises a wake up radio and a primary radio， wherein the wake up radio is configured to receive the sounding signal and the primary radio is configured to send and receive signals to and from a second communication node， respectively， wherein the sounding signal is received from the second communication node.
A first communication node， comprising：

a receiver configured to receive a sounding signal encoded at a transmission data rate；

at least one processor coupled to the receiver， the at least one processor configured to：

perform a first decoding based on the sounding signal， wherein the first decoding is based on a first measurement period of the sounding signal corresponding to a first data rate that is different than the transmission data rate； and

determine a first parameter value based on the first decoding.
The first communication node of claim 9， wherein the first data rate is greater than the transmission data rate.
The first communication node of claim 9， wherein the at least one processor is further configured to：

perform a second decoding based on the sounding signal， wherein the second decoding is based on a second measurement period of the sounding signal corresponding to a second data rate， the second measurement period being shorter than the first measurement period； and

determine a second parameter value based on the second decoding.
The first communication node of claim 11， wherein the at least one processor is further configured to：

compare the first parameter value with the second parameter value； and

determine， based on the comparing， either the first data rate or the second data rate for further communications with a second communication node， wherein the sounding signal is received from the second communication node.
The first communication node of claim 12， further comprising：

a transmitter coupled to the at least one processor， and configured to send an indicator of the determined data rate to the second communication node， wherein the receiver is further configured to receive a bit stream from the second communication node at the determined data rate.
The first communication node of claim 11， wherein the at least one processor is further configured to：

compare the first and second parameter values with a predetermined threshold； and

determine， based on the comparing， to send an indicator of a null rate to a second communication node， wherein the sounding signal is received from the second communication node.
The first communication node of claim 11， wherein the first communication node comprises a wake up radio and a primary radio， wherein the wake up radio is configured to receive the sounding signal， wherein the primary radio is configured to send and receive signals from a second communication node， wherein the sounding signal is received from the second communication node.
The first communication node of claim 11， wherein the second measurement period has a time offset with respect to the first measurement period.
A method performed by a communication node， comprising：

sending a sounding signal at a transmission data rate；

receiving a feedback signal， the feedback signal based on a first decoding of the sounding signal corresponding to a first data rate that is different than the transmission data rate；

determining a further transmission data rate based on the feedback signal； and

sending a bit stream at the further transmission data rate.
The method of claim 17， wherein the first data rate is greater than the transmission data rate.
The communication node of claim 17， wherein the sounding signal is encoded in accordance with at least one of： Manchester coding， unipolar coding， and polar coding.
The communication node of claim 17， wherein the sounding signal carries a transmission bit stream comprising at least one duplication of the following sequences of binary values： 10， 11 and 00.
A communication node， comprising：

a transmitter configured to：

send a sounding signal at a transmission data rate；

a receiver configured to：

receive a feedback signal， the feedback signal based on a first decoding of the sounding signal corresponding to a first data rate that is different than the transmission data rate； and

at least one processor coupled to the receiver and the transmitter， the at least one processor configured to：

determine a further transmission data rate based on the feedback signal， wherein the receiver is configured to send a bit stream at the further transmission data rate.
The communication node of claim 21， wherein the first data rate is greater than the transmission data rate.
The communication node of claim 21， wherein the sounding signal is encoded in accordance with at least one of： Manchester coding， unipolar coding， and polar coding.
The communication node of claim 21， wherein the sounding signal carries a transmission bit stream comprising at least one duplication of the following sequences of binary values： 10， 11 and 00.