WO2018084880A1 - Enodeb assisted network ue scheduling in 5g nr-things sidelink - Google Patents

Abstract

Systems and methods of providing adjusting 5G nUE-tUE communications based on the underlying network density are generally described. The nUE reports to the eNB support for communication with tUEs and, if so, the number of tUEs. In response, the nUE receives sidelink information that includes the UE density in the eNB coverage area, values of scheduling parameters dependent on the UE density and/or a sidelink density indicator indicating a change in the UE density. The parameters include the MCS efficiency, the maximum number of PRAs able to be scheduled by the nUE, and the maximum number of retransmissions by the nUE. The parameter values are determined by the nUE based on the UE density if the UE density is supplied by the eNB but the values are not. The nUE schedules communications with the tUEs based on the sidelink information.

Description

[0001] This application claims the benefit of priority to United States

Provisional Patent Application Serial No. 62/418, 110, filed, November 4, 2016, entitled "ENODEB ASSISTED NETWORK UE SCHEDULING IN 5G NR-

THI GS SIDELINE," which is incorporated herein by reference in its entirety

TECHNICAL FIELD

[0002] Embodiments pertain to radio access networks. Some embodiments relate to wearable devices in various cellular and wireless local area network (WLAN) networks, including Third Generation Partnership Project Long Term Evolution (3GPP LTE) networks and LTE advanced (LTE-A) networks as well as 4^th generation (4G) networks and 5^th generation (5G) networks. Some embodiments relate to 5G wearable or other "tilings" devices and network interactions, in particular handling of user and control plane data in side link communications .

BACKGROUND

[0003] The use of 3GPP LTE systems (including both LTE and LTE-A systems) has increased due to both an increase in the types of devices user equipment (UEs) using network resources as well as the amount of data and bandwidth being used by various applications, such as video streaming, operating on these UEs. For example, the growth of network use by Internet of Things (loT) UEs, which include machine type communication (MTC) devices such as sensors and may use machine-to-machine (M2M) communications, has severely strained network resources. New 3GPP standard releases related to the next generation network (5G) are taking into account the massive influx of low- data, high-delay and low power transmissions.

[0004 J One ty pe of user-based IoT devices developed recently whose popularity has exploded is "things" user equipment (tUE), such as wearable devices, in addition to one or more network UEs (nUE). Examples of wearable devices include fitness trackers, smart watches, and smart glasses. Wearable devices typically have lower processing capability, a small batter}⁷ capacity, and a low internal memory' capacity. In terms of deployment, each user may carry multiple wearable de ices, and may be located in a highly -dense populated situation with other people carrying one or more other wearable devices and nUEs. Unlike many MTC loT devices, tUEs may have a mobility similar to that of nUEs and limited functionality compared to the nUEs, independent of the type of tUE. The sideiink communication in the 5G network between a tUE and nUE, however, remains to be determined due at least in part to the vast changes in design of the 5G network.

BRIEF DESCRIPTION OF THE FIGURES

[0005] In the figures, which are not necessarily drawn to scale, like numerals may describe similar components in different views. Like numerals having different letter suffixes may represent different instances of similar components. The figures illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document.

[0006] FIG. 1 is a block diagram of a system architecture for supporting wearable devices in accordance with some embodiments.

[0007] FIG. 2 illustrates components of a communication device in accordance with some embodiments.

[0008] FIG. 3 illustrates a block diagram of a communication device in accordance with some embodiments.

Θ009] FIG. 4 illustrates another block diagram of a communication device in accordance with some embodiments.

[0010] FIG. 5 illustrates a protocol stack in accordance with some embodiments.

[0011] FIGS. 6A and 6B illustrate downlink and uplink subframe structures in accordance with some embodiments.

[0012] FIG. 7 illustrates a flowchart of scheduling and resource allocation in accordance with some embodiments. DETAILED DESCRIPTION

[0013] The following description and the drawings sufficiently illustrate specific embodiments to enable those skilled in the art to practice them.. Other embodiments may incorporate structural, logical, electrical, process, and other changes. Portions and features of some embodiments may be included in, or substituted for, those of other embodiments. Embodiments set forth in the claims encompass all available equivalents of those claims.

[0014] FIG. 1 is a block diagram of a system architecture 100 for supporting wearable devices. As shown, the system architecture 100 includes a netw ork user equipment (nUE) 110, one or more things user equipment (tUEs) 120a, 120b, 120c, an evolved universal terrestrial radio access network (E- UTRAN or EUTRAN) base station (BS, also referred to as an evolved NodeB (e^'NB)) or 5G base station 130, and an evolved packet core (EPC) or 5G core 140. The nUE 1 10 and the tUEs 120 together form a personal area netw ork (PAN) 150 or side link cell. The EUTRAN thus may include eNBs 130 that provide user plane and control plane protocol terminations towards the nUE 1 10. The eNBs 130 may be connected by means of the X2 interface. The eNBs 130 may also be connected to a Mobility Management Entity (MME) the via a Sl~ MME and to a Serving Gateway (S-GW) via a S l-U.

[0015J The nUE 110 may be any user equipment capable of

communicating with the base station 130 via an air interface. According to some examples, the nUE 110 may be a mobile phone, a tablet computer, a wearable device such as a smart watch, etc. According to some examples, the nUE may be a tUE that is capable of communicating with the base station 130 and has sufficient batten' life (e.g., greater than 30%, 50%, 75%, 90% of the maximum amount of battery power etc.). Hie nUE 110 may have a full infrastructure network access protocol and full control and user plane (C U-dlane) functions. As shown, the nUE 110 may communicate with the base station 130 via a Xu-d (direct) air interface.

[0016] Each tUE 120 may include a wireless interface (Xu-d or Xu-s) for communicating within the PAN 150. The tUE 120 may communicate with the nUE 110 or another tUE 120 through the Xu-s (sidelink) intra-P AN air interface. The tUE 120 may include, for example, smart watches, smart glasses, smart headphones, fitness sensors, movement trackers, sleep sensors, etc. In some embodiments, the tUE 120 may also communicate directly with the base station 130 via a Xu-d air interface. In some embodiments, the tUE 12.0 may be unable to communicate directly with the base station 130. The nUE 110 may act as a master UE in a sidelink cell formed by the nUE 110 and associated tUEs 120. The tUE 120 may have a full sidelink protocol stack and may or may not have standalone direct link protocol stack. The tUE 120 may act as a slave UE in the side link cell.

[0017] The base station 130 may be a base station of a cellular network. The base station 130 is may be an eNB in a LTE cellular network or a 5G Radio Access Network (RAN) in a next generation (5G) network. In the latter case, the 5G RAN may be a standalone base station or a booster cell anchored to an eNB. The base station 130 may communicate with a core network 140 (EPC for LTE or 5G core for 5G) using an SI interface. For convenience, the term eNB will be used herein to denote either a LTE or 5G base station. Some aspects of the subject technology are directed to defining the air interface between the base station and the PAN of the nUE 110 and the tUEs 120, while other aspects are directed to defining the intra-PAN air interface for enabling low power operation with diverse traffic and application requirements.

[0018J Some aspects of the subject technology may be implemented in conjunction with a LTE network, and, in some cases, leverages device-to-device (D2D) and machine-type communications (MTC) technology. However, for connectivity techniques, aspects of the subject technology address high-density scenarios. For LTE-D2D, some aspects of the subject technology enable PAN- specific identity, unicast in intra-PAN communication, uplink and downlink features, and operation in unlicensed bands. For LTE-MTC, some aspects of the subject technology provide support for diverse traffic, including high rate traffic and low latency traffic.

[0019] The base station 130 may be a macro base station or a smaller base station (micro, pico, nano) that may terminate the air interface protocol. In some embodiments, the base station 130 may fulfill various logical functions for the RAN including, but not limited to, RNC (radio network controller functions) such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management. In accordance with embodiments, UEs 120 may be configured to communicate orthogonal frequency division multiplexed (OFDM) communication signals with the base station 130 over a multicarrier communication channel in accordance with an OFDMA communication technique. The OFDM signals may comprise a plurality of orthogonal subcarriers. In other embodiments, such as tliose related to 5G systems, non-OFDM signals may be used in addition or instead of OFDM signals.

[0020] The Si interface may be the interface that separates the RAN 130 and the core network 140. The SI interface may be split into two parts: the Sl- U, which may carry traffic data between base stations of the RAN 130 and other elements of the core network, such as a serving GW, and the S l-MME, which may be a signaling interface between the RAN 130 and an MME.

[0021] FIG. 2 illustrates components of a communication device in accordance with some embodiments. The communication device 200 may be a UE, eNB or other network component as described herein. The communication device 200 may be a stationary, non-mobile device or may be a mobile device. In some embodiments, the UE 200 may include application circuitry 202, baseband circuitry 204, Radio Frequency (RF) circuitry 206, front-end module (FEM) circuitry 208 and one or more antennas 210, coupled together at least as shown. At least some of the base band circuitry 204, RF ci rcuitry 206, and FEM circuitr ' 208 may form a transceiver, in some embodiments, other network elements, such as the MME may contain some or all of the components shown in FIG. 2.

[Θ022] The application or processing circuitry' 202 may include one or more application processors. For example, the application circuitry 202 may include circuitry such as, but not limited to, one or more single-core or multi- core processors. The processor(s) may include any combination of general- purpose processors and dedicated processors (e.g., graphics processors, application processors, etc.). The processors may be coupled with and/or may include memory/storage and may be configured to execute instructions stored in the memory/storage to enable various applications and/or operating systems to run on the system. [0023] The baseband circuitry 204 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The baseband circuitry 204 may include one or more baseband processors and/or control logic to process baseband signals received from a receive signal path of the RF circuitry 206 and to generate baseband signals for a transmit signal path of the RF circuitry 206. Baseband processing circuity 204 may interface with the application circuitry 202 for generation and processing of the baseband signals and for controlling operations of the RF circuitry 206. For example, in some embodiments, the baseband circuitry 204 may include a second generation (2G) baseband processor 204a, third generation (3G) baseband processor 204b, fourth generation (4G) baseband processor 204c, and/or other baseband processor(s) 204d for other existing generations, generations in development or to be developed in the future (e.g., fifth generation (5G), 5G, etc.). The baseband circuitry 204 (e.g., one or more of baseband processors 204a-d) may handle various radio control functions that enable communication with one or more radio networks via the RF circuitry 206. The radio control functions may include, but are not limited to, signal modulation/demodulation,

encoding/decoding, radio frequency shifting, etc. In some embodiments, modulation/demodulation circuitry of the baseband circuitry 204 may include FFT, preceding, and/or constellation mapping/demapping functionality . In some embodiments, encoding/decoding circuitry of the baseband circuitry 204 may include convolution, tail-biting convolution, turbo, Viterbi, and/or Low Density Parity Check (LDPC) encoder/decoder functionality. Embodiments of modulation/demodulation and encoder/decoder functionality are not limited to these examples and may include other suitable functionality in other embodiments.

[0024J In some embodiments, the baseband circuitry 204 may include elements of a protocol stack such as, for example, elements of a Evolved UTRAN (EUTRAN) protocol including, for example, physical (PHY), media access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), radio resource control (RRC) elements, and/or Non-Access Stratum (NAS) elements. A central processing unit (CPU) 204e of the baseband circuitry 204 may be configured to run elements of the protocol stack for signaling of the PHY, MAC, RLC, PDCP and/or RRC layers, and/or NAS. In some embodiments, the baseband circuitry may include one or more audio digital signal processor(s) (DSP) 204f. The audio DSP(s) 204f may be include elements for compression/decompression and echo cancellation and may include other suitable processing elements in other embodiments. Components of the baseband circuitry may be suitably combined in a single chip, a single chipset, or disposed on a same circuit board in some embodiments. In some embodiments, some or all of the constituent components of the baseband circuitry 204 and the application circuitry 202 may be implemented together such as, for example, on a system on a chip (SOC).

Θ025] In some embodiments, the baseband circuitry 204 may provide for communication compatible with one or more radio technologies. For example, in some embodiments, the baseband circuitry 204 may support communication with an EUTRAN and/or other wireless metropolitan area networks (WMAN), a wireless local area network (WLAN), a wireless personal area network (WPAN). Embodiments in which the baseband circuitry 204 is configured to support radio communications of more than one wireless protocol may be referred to as multi-mode baseband circuitry. In some embodiments, the device can be configured to operate in accordance with communication standards or other protocols or standards, including Institute of Electrical and Electronic Engineers (IEEE) 802.16 wireless technology (WiMax), IEEE 802.11 wireless technology (WiFi) including IEEE 802. i 1 ad, which operates in the 60 GHz millimeter wave spectrum, various other wireless technologies such as global system for mobile communications (GSM), enhanced data rates for GSM evolution (EDGE), GSM EDGE radio access network (GERAN), universal mobile telecommunications system (UMTS), UMTS terrestrial radio access network (UTRAN), or other 2G, 3G, 4G, 5G, etc. technologies either already- developed or to be developed.

[0026] RF circuitry 206 may enable communication with wireless networks using modulated electromagnetic radiation through a non-solid medium. In various embodiments, the RF circuitry 206 may include switches, filters, amplifiers, etc. to facilitate the communication with the wireless network. RF circuitry 206 may include a receive signal path which may include circuitry to down-convert RF signals received from the FEM circuitry 208 and provide baseband signals to the baseband circuitry 204. RF^" circuitry 206 may also include a transmit signal path which may include circuitry to up-convert baseband signals provided by the baseband circuitry 204 and provide RF output signals to the FEM circuitry 208 for transmission.

[0027J In some embodiments, the RF circuitry 206 may include a receive signal path and a transmit signal path. The receive signal path of the RF circuits"}' 206 may include mixer circuitry 206a, amplifier circuitry 206b and filter circuitry 206c. The transmit signal path of the RF^" circuitry 206 may include filter circuitry 206c and mixer circuitry 206a. RF circuitry 206 may also include synthesizer circuitry 206d for synthesizing a frequency for use by the mixer circuitry 206a of the receive signal path and the transmit signal path. In some embodiments, the mixer circuitrv' 206a of the receive signal path may be configured to down-convert RF signals received from, the FEM circuitry 208 based on the synthesized frequency provided by synthesizer circuitry- 206d. The amplifier circuitry 206b may be configured to amplify the down-converted signals and the filter circuitry 206c may be a low-pass filter (EPF) or band-pass filter (BPF) configured to remove unwanted signals from the down-converted signals to generate output baseband signals. Output baseband signals may be provided to the baseband circuitry 204 for further processing. In some embodiments, the output baseband signals may be zero-frequency baseband signals, although this is not a requirement. In some embodiments, mixer circuitry 206a of the receive signal path may comprise passive mixers, although the scope of the embodiments is not limited in this respect.

[0028] In some embodiments, the mixer circuitry 206a of the transmit signal path may be configured to up-convert input baseband signals based on the synthesized frequency provided by the synthesizer circuitry 206d to generate RF output signals for the FEM circuitry 208. The baseband signals may be provided by the baseband circuitry 204 and may be filtered by filter circuitry- 206c. The filter circuitry 206c may include a low-pass filter (EPF), although the scope of the embodiments is not limited in tins respect.

[0029] In some embodiments, the mixer circuitry 206a of the receive signal path and the mixer circuitry 206a of the transmit signal path may include two or more mixers and may be arranged for quadrature downconversion and/or upconversion respectively. In some embodiments, the mixer circuitry 206a of the receive signal path and the mixer circuitry 206a of the transmit signal path may include two or more mixers and may be arranged for image rejection (e.g., Hartley image rejection). In some embodiments, the mixer circuitry 206a of the receive signal path and the mixer circuitr - 206a may be arranged for direct downconversion and/or direct upconversion, respectively. In some embodiments, the mixer circuitry 206a of the receive signal path and the mixer circuitry 206a of the transmit signal path may be configured for super-heterodyne operation.

[0030] In some embodiments, the output baseband signals and the input baseband signals may be analog baseband signals, although the scope of the embodiments is not limited in this respect. In some alternate embodiments, the output baseband signals and the input baseband signals may be digital baseband signals. In these alternate embodiments, the RF circuitry 206 may include analog-to-digital converter (ADC) and digital-to-analog converter (DAC) circuitry and the baseband circuitry 204 may include a digital baseband interface to communicate with the RF circuitry 206.

[0031] In some dual -mode embodiments, a separate radio IC circuitry may be provided for processing signals for each spectrum, although the scope of the embodiments is not limited in this respect.

[0032] In some embodiments, the synthesizer circuitry 206d may be a fractional -N synthesizer or a fractional N/N+I synthesizer, although the scope of the embodiments is not limited in this respect as other types of frequency synthesizers may be suitable. For example, synthesizer circuitry 206d may be a delta-sigma synthesizer, a frequency multiplier, or a synthesizer comprising a phase-locked loop with a frequency divider.

[0033] The synthesizer circuitry 206d may be configured to synthesize an output frequency for use by the mixer circuitry 206a of the RF circuitry 206 based on a frequency input and a divider control input. In some embodiments, the synthesizer circuitry 206d may be a fractional N/N+ l synthesizer.

[0034] In some embodiments, frequency input may be provided by a voltage controlled oscillator (VCO), although that is not a requirement. Divider control input may be provided by either the baseband circuitry 204 or the applications processor 202 depending on the desired output frequency. In sorne embodiments, a divider control input (e.g., N) may be determined from a lookup table based on a channel indicated by the applications processor 202.

[0035] Synthesizer circuitry 206d of the RF circuitry 206 may include a divider, a delay-locked loop (DLL), a multiplexer and a phase accumulator. In some embodiments, the divider may be a dual modulus divider (DMD) and the phase accumulator may be a digital phase accumulator (DPA). In some embodiments, the DMD may be configured to divide the input signal by either N or N+ l (e.g., based on a carr out) to provide a fractional division ratio. In some example embodiments, the DLL may include a set of cascaded, tunable, delay elements, a phase detector, a charge pump and a D-type flip-flop. In these embodiments, the delay elements may be configured to break a VCO period up into Nd equal packets of phase, where Nd is the number of delay elements in the delay line. In this way, the DLL provides negative feedback to help ensure that the total delay through the delay line is one VCO cycle.

[0036] In some embodiments, synthesizer circuitry 206d may be configured to generate a carrier frequency as the output frequency, while in other embodiments, the output frequency may be a multiple of the carrier frequency (e.g., twice the carrier frequency, four times the carrier frequency) and used in conjunction with quadrature generator and di vider circuitry to generate multiple signals at the earner frequency with multiple different phases with respect to each other. In some embodiments, the output frequency may be a LO frequency (flo). In some embodiments, the RF circuitry 206 may include an IQ/polar converter.

[0037] FEM circuitry 208 may include a receive signal path which may include circuitry configured to operate on RF signals received from one or more antennas 210, amplify the received signals and provide the amplified versions of the received signals to the RF circuitry 206 for further processing. FEM circuitry 208 may also include a transmit signal path which may include circuitry configured to amplify signals for transmission provided by the RF circuitry 206 for transmission by one or more of the one or more antennas 210.

[0038] In some embodiments, the FEM circuitry 208 may include a

TX/RX switch to switch between transmit mode and receive mode operation. The FEM circuitry may include a receive signal path and a transmit signal path. The receive signal path of the FEM circuitry may include a low -noise amplifier (LNA) to amplify received RF signals and provide the amplified received RF signals as an output (e.g., to the RF circuitry 206). The transmit signal path of the FEM circuitry 208 may include a power amplifier (PA) to amplify input RF signals (e.g., provided by RF circuitry 206), and one or more filters to generate RF signals for subsequent transmission (e.g., by one or more of the one or more antennas 210.

[0039] In some embodiments, the communication device 200 may include additional elements such as, for example, memory/storage, display, camera, sensor, and/or input/output (I/O) interface as described in more detail below. In some embodiments, the communication device 200 described herein may be part of a portable wireless communication device, such as a personal digital assistant (PDA), a laptop or portable computer with wireless

communication capability, a web tablet, a wireless telephone, a smartphone, a wireless headset, a pager, an instant messaging device, a digital camera, an access point, a television, a medical device (e.g., a heart rate monitor, a blood pressure monitor, etc.), or other device that may receive and/or transmit information wirelessly. In some embodiments, the communication device 200 may include one or more user interfaces designed to enable user interaction with the system and/or peripheral component interfaces designed to enable peripheral component interaction with the system. For example, the communication device 200 may include one or more of a keyboard, a keypad, a touchpad, a display, a sensor, a non-volatile memory port, a universal serial bus (USB) port, an audio jack, a power supply interface, one or more antennas, a graphics processor, an application processor, a speaker, a microphone, and other I/O components. The display may be an LCD or LED screen including a touch screen. The sensor may include a gyro sensor, an accelerometer, a proximity sensor, an ambient light sensor, and a positioning unit. The positioning unit may communicate with components of a positioning network, e.g., a global positioning system (GPS) satellite.

[0040] The antennas 210 may comprise one or more directional or omnidirectional antennas, including, for example, dipole antennas, monopole antennas, patch antennas, loop antennas, microstrip antennas or other types of antennas suitable for transmission of RF signals. In some multiple -input multiple-output (ΜΊΜΌ) embodiments, the antennas 210 may be effectively separated to take advantage of spatial diversity and the different channel characteristics thai may result.

[0041 J Although the communication device 200 is illustrated as having several separate functional elements, one or more of the functional elements may be combined and may be implemented by combinations of software-configured elements, such as processing elements including digital signal processors (DSPs), and/or other hardware elements. For example, some elements may comprise one or more microprocessors, DSPs, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), radio-frequency integrated circuits (RFlCs) and combinations of various hardware and logic circuitry for performing at least the functions described herein. In some embodiments, the functional elements may refer to one or more processes operating on one or more processing elements.

[0042] Embodiments may be implemented in one or a combination of hardware, firmware and software. Embodiments may also be implemented as instructions stored on a computer-readable storage device, which may be read and executed by at least one processor to perform the operations described herein. A computer-readable storage device may include any non-transitory mechanism for storing information in a form readable by a machine (e.g., a computer). For example, a computer-readable storage device may include readonly memory (ROM), random-access memory (RAM), magnetic disk storage media, optical storage media, flash-memory devices, and other storage devices and media. Some embodiments may include one or more processors and may be configured with instructions stored on a computer-readable storage device.

[0043] FIG. 3 is a block diagram of a communication device in accordance with some embodiments. The device may be a UE, for example, such as the UE shown in FIG. 1. The physical layer circuitry 302 may perform various encoding and decoding functions that may include formation of baseband signals for transmission and decoding of received signals. The communication device 300 may also include medium access control layer (MAC) circuitry 304 for controlling access to the wireless medium. The communication device 300 may also include processing circuitry 306, such as one or more single-core or multi-core processors, and memory 308 arranged to perform the operations described herein. The physical layer circuitry 302, MAC circuitry 304 and processing circuitry 306 may handle various radio control functions that enable communication with one or more radio networks compatible with one or more radio technologies. The radio control functions may include signal modulation, encoding, decoding, radio frequency shifting, etc. For example, similar to the device shown in FIG. 2, in some embodiments, communication may be enabled with one or more of a WMAN, a WLAN, and a WPAN. In some embodiments, the communication device 300 can be configured to operate in accordance with 3 GPP standards or other protocols or standards, including WiMax, WiFi, WiGig, GSM, EDGE, GERAN, UMTS, UTRAN, or other 3G, 3G, 4G, 5G, etc. technologies either already developed or to be developed. The communication device 300 may include transceiver circuitry 312 to enable communication with other external devices wirelessly and interfaces 314 to enable wired communication with other external devices. As another example, the transceiver circuity 312 may perform various transmission and reception functions such as conversion of signals between a baseband range and a Radio Frequency (RF) range.

[0044] The antennas 301 may comprise one or more directional or omnidirectional antennas, including, for example, dipole antennas, monopole antennas, patch antennas, loop antennas, microstrip antennas or other types of antennas suitable for transmission of RF signals. In some M1MO embodiments, the antennas 301 may be effectively separated to take advantage of spatial diversity and the different channel characteristics that may result.

[0045J Although the communication device 300 is illustrated as having several separate functional elements, one or m ore of the functional elem ents may be combined and may be implemented by combinations of software-configured elements, such as processing elements including DSPs, and/or other hardware elements. For example, some elements may comprise one or more

microprocessors, DSPs, FPGAs, ASICs, RFICs and combinations of various hardware and logic circuity for performing at least the functions described herein. In some embodiments, the functional elements may refer to one or more processes operating on one or more processing elements. Embodiments may be implemented in one or a combination of hardware, firmware and software. Embodiments may also be implemented as instructions stored on a computer- readable storage device, which may be read and executed by at least one processor to perform the operations described herein.

[0046] FIG. 4 illustrates another block diagram of a communication device in accordance with some embodiments. In alternative embodiments, the communication device 400 may operate as a standalone device or may be connected (e.g., networked) to other communication devices. In a networked deployment, the communication device 400 may operate in the capacity of a server communication device, a client communication device, or both in server- client network environments. In an example, the communication device 400 may act as a peer communication device in peer-to-peer (P2P) (or other distributed) network environment. The communication device 400 may be a UE, eNB, PC, a tablet PC, a STB, a PDA, a mobile telephone, a smart phone, a web appliance, a network router, switch or bridge, or any communication device capable of executing instructions (sequential or otherwise) that specify actions to be taken by that communication device. Further, while only a single communication device is illustrated, the term '^"communication device" shall also be taken to include any collection of communication devices that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies discussed herein, such as cloud computing, software as a service (SaaS), other computer cluster configurations.

Θ047] Examples, as described herein, may include, or may operate on, logic or a number of components, modules, or mechanisms. Modules are tangible entities (e.g., hardware) capable of performing specified operations and may be configured or arranged in a certain manner. In an example, circuits may be arranged (e.g., internally or with respect to external entities such as other circuits) in a specified manner as a module. In an example, the whole or part of one or more computer systems (e.g., a standalone, client or server computer system) or one or more hardware processors may be configured by firmware or software (e.g., instructions, an application portion, or an application) as a module thai operates to perform specified operations. In an example, the software may reside on a communication device readable medium. In an example, the software, when executed by the underlying hardware of the module, causes the hardware to perform the specified operations.

0048J Accordingly, the term "module" is understood to encompass a tangible entity, be that an entity that is physically constructed, specifically configured (e.g., hardwired), or temporarily (e.g., transitorily) configured (e.g., programmed) to operate in a specified manner or to perform part or all of any operation described herein. Considering examples in which modules are temporari ly configured, each of the modules need not be instantiated at any one moment in time. For example, where the modules comprise a general-purpose hardware processor configured using software, the general-purpose hardware processor may be configured as respective different modules at different times. Software may accordingly configure a hardware processor, for example, to constitute a particular module at one instance of time and to constitute a different module at a different instance of time.

[0049] Communication device (e.g., computer system) 400 may include a hardware processor 402 (e.g., a central processing unit (CPU), a graphics processing unit (GPU), a hardware processor core, or any combination thereof), a mam memory 404 and a static memory 406, some or all of which may communicate with each other via an interlink (e.g., bus) 408. The

communication device 400 may further include a display unit 410, an alphanumeric input device 412 (e.g., a keyboard), and a user interface (UI) navigation device 414 (e.g., a mouse). In an example, the display unit 410, input device 412 and UI navigation device 414 may be a touch screen display. The communication device 400 may additionally include a storage device (e.g., drive unit) 416, a signal generation device 418 (e.g., a speaker), a network interface device 42,0, and one or more sensors 42 , such as a global positioning system (GPS) sensor, compass, accelerometer, or other sensor. The communication device 400 may include an output controller 428, such as a serial (e.g., universal serial bus (USB), parallel, or other wired or wireless (e.g., infrared (IR), near field communication (NFC), etc.) connection to communicate or control one or more peripheral devices (e.g., a printer, card reader, etc.). [005Θ] The storage device 416 may include a communication device readable medium 422 on which is stored one or more sets of data structures or instractions 424 (e.g., software) embodying or utilized by any one or more of the techniques or functions described herein. The instructions 424 may also reside, completely or at least partially, within the main memory 404, within static memory 406, or within the hardware processor 402 during execution thereof by the communication device 400. In an example, one or any combination of the hardware processor 402, the main memory 404, the static memory 406, or the storage device 416 may constitute communication device readable media.

[0051] While the communication device readable medium 422 is illustrated as a single medium, the term "communication device readable medium" may include a single medium or multiple media (e.g., a centralized or distributed database, and/or associated caches and servers) configured to store the one or more instractions 424.

[0052] The term "communication device readable medium" may include any medium that is capable of storing, encoding, or carrying instructions for execution by the communication device 400 and that cause the communication device 400 to perform any one or more of the techniques of the present disclosure, or that is capable of storing, encoding or carrying data structures used by or associated with such instructions. Non-limiting communication device readable medium examples may include solid-state memories, and optical and magnetic media. Specific examples of communication device readable media may include: non-volatile memory, such as semiconductor memory devices (e.g., Electrically Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory- (EEPROM)) and flash memory devices; magnetic disks, such as internal hard disks and removable disks;

magneto-optical disks; Random Access Memory (RAM); and CD-ROM and DVD-ROM disks. In some examples, communication device readable media may include non-transitory communication device readable media. In some examples, communication device readable media may include communication device readable media that is not a transitory propagating signal.

[0053] The instructions 424 may further be transmitted or received over a communications network 426 using a transmission medium via the network interface device 420 utilizing any one of a number of transfer protocols (e.g., frame relay, internet protocol (IP), transmission control protocol (TCP), user datagram protocol (UDP), hypertext transfer protocol (HTTP), etc.). Example communication networks may include a local area network (LAN), a wide area network (WAN), a packet data network (e.g., the Internet), mobile telephone networks (e.g., cellular networks), Plain Old Telephone (POTS) networks, and wireless data networks (e.g., IEEE 802.11 family of standards known as WiFi®, IEEE 802.16 family of standards known as WiMax®), IEEE 802.15.4 family of standards, a LTE family of standards, a UMTS family of standards, peer-to-peer (P2P) networks, among others. In an example, the network interface device 420 may include one or more physical jacks (e.g., Ethernet, coaxial, or phone jacks) or one or more antennas to connect to the communications network 426. In an example, the network interface device 420 may include a plurality of antennas to wirelessly communicate using at least one of single-input multiple -output (SIMO), MIMO, or multiple-input single-output (MISO) techniques. In some examples, the network interface device 420 may wirelessly communicate using Multiple User MIMO techniques. The term "transmission medium" shall be taken to include any intangible medium that is capable of storing, encoding or carrying instructions for execution by the communication device 400, and includes digital or analog communications signals or other intangible medium to facilitate communication of such software.

[0054] As above, in certain embodiments, a tUE, such as a wearable device or vehicle-embedded device, may be temporarily or permanently constrained to communicate with the EUTRAN through a nUE. Several tUEs may be associated with a particular nUE to form a PAN. A large number of nUEs may be located in a particular geographical region served by a single EUTRAN. Each nUE may be associated with a different PAN, which may- create a high density network scenario. The RAN may furthermore assign a common resource pool for wearable communication. This resource pool may be shared among all of the PANs in the geographical area and within each PAN on a contention-based resource access basis. Each nUE may have two higher layer protocol stacks, one for the Xu-s interface with the tUE and one for the Xu-d interface with the EUTRAN. Dependent on the embodiment, the tUEs may have the same two higher layer protocol stacks or may have a single higher layer protocol stack for one for the Xu-s interface with the nUE.

[0055] Physical resource allocation (PRA) handling by the nUE may involve several procedures to make challenging decisions in the PAN. A first decision includes allocation of uplink (UL) and downlink (DL) subframes within a particular frame of the time division duplexing (TDD) system that uses the Xu- s interface. The nUE may also decide scheduling among one or more tUEs with different buffer sizes in a given DL subframe. Similarly, for a given DL subframe the nUE may decide scheduling among one or more tUEs with different buffer sizes. To support nUE resource scheduling, signaling mechanisms between the nUE and tUEs may enable the nUE to efficiently make scheduling decisions. For example, the nUE may use information regarding the amount of buffered data at each of the tUEs for UL transmission scheduling. Similarly, the nUE may transmit the UL or DL scheduling information to the associated tUEs.

[0056] In addition to scheduling for communication with the tUEs, the nUE may adjust scheduling parameters based on the density of the underlay network to balance sidelink fairness and throughput. This is to say that the nUE may adjust scheduling parameters for the PAN dependent on the number of other nUEs and, if possible, tUEs connected to the other nUEs. However, the nUE may not be able to obtain this information from the other nUEs directly and may instead communicate with the serving eNB of the EUTRAN to which the nUE is attached. Thus, the nUE may use the Xu-d link with the eNB to obtain the density of the sidelink and to regulate nUE scheduling parameters.

[0057] FIG. 5 illustrates a protocol stack in accordance with some embodiments. The protocol stack may be provided in any of the nUEs or tUEs described in FIGS. 1-4. The higher layer protocol stack (tSL-HL) 504 may refer primarily to the protocol layers between the PHY (tSL~PHY) 506 and

IP/Application layers 502 in the user plane (UP) and between the tSL-PHY 506 and tSL radio resource control layer (tSL-RRC) 508 for the control plane (CP). The tSL-HL 504 may refer to one or more of the MAC, RLC and PDCP layers of legacy LIE protocol layers. [0058] FIGS. 6A and 6B illustrate downlink and uplink subframe structures in accordance with some embodiments. The DL and UL subframe structures 610, 630 may be used by any of the nUEs or tUEs shown in FIGS. 1- 5. Each DL and UL subframe 610, 630 may be lms, although other nurnerologies such as subframe lengths of 0.25ms, 0.5ms, or 2ms can also be supported. Each DL and UL subframe 610, 630 may be divided into multiple physical resource blocks (PRB) in the frequency domain in which each PRB may occupy 3 subcarriers over one subframe. For a subcarrier spacing of 60 kHz and subframe duration of 1ms, each PRB may occupy 180 kHz over 1 iris. The PRBs may be grouped into subchannels in which each subchannel occupies 6 PRBs consecutive in the frequency domain. The minimum system bandwidth is of the size of a subchannel. The channels may be transmitted on a PRA, which may be an aggregation of multiple continuous PRBs. Another subcarrier spacing may be, for example, 15kHz or 75kHz. Similarly, one PRB may occupy other numbers of subcarriers, for example, 12 subcarriers. The design described herein is not limited by the example numerology.

[0059] Each DL and UL subfranie 610, 630 may be divided into a number of sections, each of which is addressed to the same tUE. The first symbol in the subframe 610, 630 may be a common control channel 612 and may indicate whether the data channel 622 is an UL or DL data channel. Thus, the common control channel 6 2 may be a DL common control channel independent of whether the data channel 622 in the subframe 610, 630 is UL or DL. The common control channel 612 may have a 10 bit pay load in which the UL/DL indication is a single bit.

[0060] The DL common control channel 612 may be followed by a

Transmitter resource Acquisition and Sounding (TAS) channel 616. The TAS channel 616 may be a DL channel in the DL subfranie 610 and an UL channel in the UL subfranie 630. The TAS channel 616 may be used by the transmitter to transmit a reference signal for measurement by the receiver. For example, in the DL subframe 610, the nUE may transmit the reference signal and the tUE may measure the reference signal The TAS channel 616 may have a 6 bit payload in which the new data indicator (NDI) is a single bit with a 2 bit repetition and 3 bit CRC. [0061] A Receiver resource Acknowledgement and Sounding (RAS) channel 618 may be provided subsequent to the TAS channel 616. The receiver, e.g., the tUE in the RAS channel 618 in the DL subframe 6 0, may transmit the measurement to the transmitter (nUE in the DL subframe 610). The RAS channel 618 may provide a CSI and power head room (PHR) report. The RAS channel 618 may ha v e a 10 bit pay load in which the modulation and coding scheme (MCS) is 4 bits with a 2 bit PHR and 4 bit CRC.

[0062] The TAS and RAS channels 616, 618 may be followed by a DL data channel 622 in a DL subframe 610, or UL data channel in a UL subframe 630. The data channel 622 may contain data provided from the transmitter to the receiver. This data may include ID and security information or user data.

[0063] The data channel 622 may be followed by an ACK/NACK channel 624. The ACK/NACK channel 624 may contain a response to transmission of the data in the data channel 622 and be used by the transmitter to determine whether retransmission of the data in the data channel 622 is to occur. The ACK NACK channel 624 may have a 10 bit pay load in which the

ACK/NACK is 2 bits with a 4 bit buffer status report (BSR) in a DL subframe 610 indicating whether data is present for transmission and 4 bit CRC.

[0064] The various sections above may be separated by guard periods

614. The guard periods 614 may be used to reduce inter-symbol interference or permit the tUE to switch between the transmitter and receiver chains. At least some of the guard periods 614 may have different lengths. For example, the guard periods between the DL common control channel 612 and the TAS channel 616, between the TAS channel 616 and the RAS channel 618 and after the ACK/NACK channel 624 may occupy 1 symbol ( 17.7us total), the guard period 614 between the RAS channel 63 8 and the data channel 622 may occupy 1 symbol + 8.33iis (26.03μ8 total) and the guard period 614 between the data channel 622 and the ACK/NACK channel 624 may occupy 2 symbols. As above, the guard period length described herein is not limited by the example numerology.

[0065] A majority of the subchannels in the system may be used to provide data between UEs. However, one or more of the subchannels may be reserved for control signaling. For example, 1-2 resource elements (REs) of one of the central 6 P Bs in the first DL subframe of each frame may provide broadcast channel information, as well as paging and discovery information. 1 RE may be defined as 1 subcarrier over 1 symbol, 1 resource unit (RU) may be defined as 3 subcarriers over 4 consecutive symbols (in total 12 REs). In some embodiments, the DL common control channel, the TAS channel, the RAS channel and the ACK channel may each occupy one RU, while the data channel may occupy the 3 subcarriers over 34 symbols. The total subframe in this embodiment may thus extend over 56 symbols (including the above guard periods). As above, the length of the different channels described herein is not limited by the example numerology.

Θ066] As above, the nUE may obtain information from the eNB

(whetiier 4G or 5G) to adjust scheduling parameters for the PAN associated with the nUE. There are at least three scheduling parameters that may have an impact on sideiink (Xu-s interface communications) performance: the efficiency of the modulation and coding scheme (MCS) used for pre -allocation scheduling, the maximum number of PRAs that can be scheduled by the nUE, and the maximum number of retransmissions.

Θ067] The first parameter is the MCS efficiency used for pre-allocation scheduling. As is clear from the subframe design shown in FIGS. 6A and 6B, the nUE may transmit scheduling decisions in the common control channel of an UL subframe and in the TAS channel in a DL subframe. It is desirable for the number of PRAs for UL transmission for a tUE to be based on the buffer size of the tUE, that is, the amount of data that the tUE has to transmit to the nUE. However, the amount of data to be carried on each PRA in the data channel (in both UL and DL subframes) may be unknown in the scheduling phase - it may instead be determined by the nUE after the RAS channel as the MCS is contained in the RAS channel. This leads to the nUE using an estimate of the MCS efficiency when determining the scheduling for the tUE.

[0068] Various issues may arise in the nUE estimating the MCS efficiency, however. If the estimated MCS efficiency is too small, the number of pre-allocated PRAs for the tUE will be larger than desirable, which may cause resource waste and generate interference to other sideiink transmissions in other PANs during the TAS RAS contention process. On the other hand, if the estimated MCS efficiency is too large, the number of pre-allocated PRAs for one tUE may be smaller than desired, which may also waste resources and increase traffic latency for the tUE.

Θ069] The MCS efficiency may var ' with the underlay network density.

The underlay network densi ty may merely be the number of peer UEs, nUEs, connected with the eNB. Alternately, the underlay network density may include the number of tUEs associated with each nUE. The number of tUEs may be reported to the eNB by each nUE, which may determine the density based on the reports and transmit the results to the nUEs. In some embodiments, the MCS efficiency may decrease with increasing density of the underlay network due to the decrease in channel conditions. This means that in general, a dense underlay network may use a low MCS efficiency in pre-allocation, while a sparse network may use a high MCS efficiency in pre-allocation.

[0070] In some embodiments, the nUE may obtain information about the underlay network density from the eNB and vary the MCS efficiency based on this information. In some embodiments, the nUE may not obtain the underlay network density from the eNB prior to communication with the tUE, instead using previously obtained information to var ' the MCS efficiency. The nUE may obtain the underlay network density periodically from the eNB or based on events such as the underlay network density changing by a predetermined amount or percentage. The underlay network density may be obtained through RR.C signaling or other higher layer signaling, or in a PDCCH, e.g. via downlink control information (DCI), or a PDSCH.

[0071] The next parameter is the maximum number of PRAs can be scheduled by the nUE. Regulations on the maximum number of PRAs a nUE can schedule may help to improve fairness in the underlay network. This is to say that interference caused to the neighboring nUEs may increase with increasing number of PRAs a nUE is able to schedule.

[0072] The maximum number of PRAs a nUE can schedule may also vary with the underlay network density. In some embodiments, the maximum number of PRAs a nUE can schedule may decrease with increasing density of the underlay network. Simulations of the average number of scheduled PRAs vs contention show that the underlay network becomes unfair among different nUEs in terms of the number of scheduled PRAs in a dense network if there is no eNB assist signaling.

[0073] This may be adjusted based on the amount of mission critical/ultra-high reliability and low latency communication (MC/URLLC) data being communicated by the tUEs in each PAN. For example, the reduction of the maximum number of PRAs a nUE can schedule with a higher percentage of MC/URLLC data may be less than that of a nUE with a lower percentage of MC/URLLC data.

[0074] The maximum number of retransmissions may also vary with the underlay network density. In particular, the maximum number of

retransmissions may decrease with increasing underlay network density. In a sparse sidelink network, the use of Hybrid Automatic Repeat Request (HARQ) may result in significant performance improvement. However, in a dense network, the improvement from the use of HARQ transmissions may disappear, and, in some cases actually have a negative impact on performance metrics due to the inability to transmit the HARQ transmission or the HARQ transmission being corrupted due to interference (for example, the HARQ transmission indicating a NACK even though the data corresponding to the HARQ transmission has been successfully received).

[0075] FIG. 7 illustrates a flowchart of scheduling and resource allocation in accordance with some embodiments. The method may be performed by any nUE shown in FIGS. 1 -4. As indicated, the nUE may at operation 702 encode and generate a communication to a serving eNB whether or not the nUE is able to support sidelink transmissions (communications through the Xu-s interface). The nUE may provide this in a single bit indication in a control message, such as in a Radio Resource Control (RRC) message (e.g., RRC connection request) or other higher layer signaling. In some embodiments, the nUE may additionally report how many tUEs are in the PAN. In some embodiments, the nUE may update the information periodically, when requested or when an event, such as a significant change in the number of tUEs or amount of a particular type of data (e.g., MC/URLLC vs. non-MC/URLLC) occurs. In this case, the nUE may report the change in a PUCCH or other control signal that occurs more frequently than the RRC signaling. If no sidelink condition report is received ai the eNB, then the eNB may assume that the nUE does not support sidelink transmission.

[0076] The eNB may determine the underlay network density based on the collection of nUE reports. In some circumstances, if the eNB has not received a report from die nUE, the eNB may estimate the underlay network density. At operation 704, the nUE may receive and decode sidelink

information from the eNB. In various embodiments, the sidelink information may be provided in a single message or may be provided through different mechanisms. For example, the nUE may receive a sidelink configuration from the eNB in a RRC configuration message, and may also receive a sidelink density indicator (SDI) from the eNB in the DCI of a PDCCH. Each nUE may receive an independent sidelink configuration and SDI from the eNB. The sidelink configuration may include one or more of: MCS efficiency selected for pre-allocation scheduling, maximum number of PRAs that can be scheduled by the nUE in sidelink transmission, and suggested maximum number of HARQ retransmissions for the sidelink.

[0077] The nUE may use the information from the eNB at operation 706.

In particular, based on the eNB sidelink configuration or SDI in the DCI, the nUE may adaptively configure scheduling algorithm in the sidelink. The scheduling algorithm may be affected by the proportion of the type of communications in the PAN. If no sidelink configuration is received from the eNB at the nUE, the nUE may use default values of the scheduling parameters. The default values may be preconfigured and stored in the memory of the nUE. The SDI may be a 2 bit indicator in the DCI that indicates density changes of the underlay network. The SDI and nUE responses may be summarized in Table 1.

Table 1. eNB assisted nUE scheduling SDI

increase number of HARQ (or enable HARQ)

11 reset reset to defauit values

[0078] Hie nUEs may be controlled individually. In some embodiments, even though the global environment may change, the eNB may supply different SDIs to different nUEs. In some embodiments, the amount of increase or reduction may be dependent on the nUE, and thus be controlled individually. In other embodiments, the amount of increase or reduction may be global and thus all nUEs that support sidelink communications may adjust the parameters in the same manner by the same amount. In some embodiments, the number of bits may be increased to provide more granularity among the parameter adjustments. Such granularity may be used, for example, to discriminate among nUEs based on proportion of the types of tUEs or tUE UL or DL data in the PAN. For example, for nUEs having a high proportion of MC/URLLC data or data related to applications in which latency is of little consideration, the MCS efficiency- may be reduced to mcrease reliability when the density changes by a relatively small amount compared with other nUEs.

[0079] The SDI may be used with the configuration to indicate the density change and whether or not to adjust the scheduling parameters. The decision of whether or not to adjust may depend, in some embodiments, on the relative density. For example, if the underlying network is relatively sparse, a change in the parameters due to a slight change in density may not provide any benefit, as shown by the simulations. On the other hand, the same change in density for a relatively dense network may make a parameter change desirable. Thus, the SDI may indicate no parameter change even if the density changes by an amount/percent that would cause a parameter change under other

circumstances and vice-versa. The SDI may thus be dependent on the underlying network density (either before or after the change) as well as the density change. In other embodiments, a predetermined the density change may cause a change in parameter value, independent of the density.

[0080] In another embodiment, rather than being supplied with values for the sidelink configuration parameters, the nUE may determine the values of the parameters in the sidelink configuration. In this case, the nUE may still provide the sidelink support information (and perhaps number of tUEs) to the eNB. The eNB may provide the nUE with the density information. The density information may include the size of the coverage area and the number of all nUEs or all UEs (nUEs and tUEs) in the coverage area. The nUE can then use this information to determine the appropriate sidelink configuration parameters and thus scheduling using the sidelink scheduling algorithm. If no sidelink configuration message is received at the nUE, for example in the RRC configuration, the nUE may use a default density value.

[0081] At operation 708, after adjusting the sidelink scheduling algorithm, the eNB may subsequently schedule the tUEs in the PAN. Each tUE in the PAN may be scheduled based on internal PAN aspects, such as the type of communication and amount of pending UL and DL data for the tUE, and external PAN aspects, such as the number of other nUEs and perhaps tUEs. The nUE may communicate DL or UL subframes with the tUEs of the PAN.

Examples

Example 1 is an apparatus of a user equipment (UE), the apparatus comprising: a memory: and processing circuitry in communication with the memory and arranged to: encode, for transmission to an evolved NodeB (eNB) through a direct (Xu-d) interface, a sidelink report, the sidelink report comprising an indication of whether the UE supports communication with another UE through a (Xu-s) sidelink interface: after transmission of the sidelink report, decode sidehnk information from the eNB, the sidelink information dependent on a density of at least UEs in communication with the eNB through the direct interface; adjust a communication schedule between the UE and the other UE based on the sidelink information; and send, for transmission to the other UE through the sidelink interface, at least one of control or data signals based on the communication schedule.

[0084] In Example 2, the subject matter of Example 1 optionally includes, wherein: the sidelink report further comprises a number of other UEs with which the UE communicates through the sidelink interface, and the density of at least UEs in communication with the eNB through a Xu-d interface further comprises UEs in communication, through a Xu-s interface, with one of the UEs in communication with the eNB through a Xu-d interface.

[0085] In Example 3, the subject matter of any one or more of Examples

1-2 optionally include, wherein the processing circuitry is configured to: adjust the communication schedule between the UE and the other UEs based on a scheduling parameter, the scheduling parameter comprising at least one of: an efficiency of a modulation and coding scheme (MCS) used for pre-allocation scheduling of communication with the other UE, a maximum number of Physical Resource Allocations (PRAs) that are available to be scheduled by the UE, and a maximum, number of retransmissions by the UE.

[0086] In Example 4, the subject matter of Example 3 optionally includes, wherein: die sidelink information comprises a sidelink configuration that comprises values for the scheduling parameter.

[0087] In Example 5, the subject matter of Example 4 optionally includes, wherein: the sidelink configuration is received by the UE in a Radio Resource Control (RRC) message from the eNB.

[0088] In Example 6, the subject matter of any one or more of Examples

3-5 optionally include, wherein: the sidelink information comprises a sidelink configuration that comprises a density of UEs in a coverage area of the eNB, independent of whether the UEs are in direct communication with the eNB, and is free from values for the scheduling parameter, and the processing circuitry is configured to determine the values for the scheduling parameter based on the density of UEs.

[0089] In Example 7, the subject matter of any one or more of Examples 3-6 optionally include, wherein: the sidelink information comprises a sidelink density indicator (SDI) that indicates a change in the density of at least UEs in communication with the eNB through a Xu-d interface, and the processing circuitry is confi gured to determine a change in values of the scheduling parameter based on the SDI,

[009Θ] In Example 8, the subject matter of Example 7 optionally includes, wherein: the SDI is received from the eNB in downlink control information (DCI). [0091] In Example 9, the subject matter of any one or more of Examples

7-8 optionally include, wherein the processing circuitry is further configured to: in response to an indication in the SDI of no change in the density, maintain the at least one of the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions, in response to an indication in the SDI of an increase in the density, decrease at least one of: the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions, and in response to an indication in the SDI of a decrease in the density, increase: at least one of the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions.

Θ092] In Example 10, the subject matter of any one or more of

Examples 7-9 optionally include, wherein the processing circuitry is further configured to: in response to an indication in the SDI to reset the scheduling parameter, reset the at least one of the MCS efficiency, the maximum, number of PRAs, and the maximum number of retransmissions to a default value.

[0093] In Example 1 1, the subject matter of any one or more of

Examples 7-10 optionally include, wherein: the SDI is received from the eNB in downlink control information (DCI).

[0094] In Example 12, the subject matter of any one or more of Examples 7-11 optionally include, wherein: the indication in the SDI is dependent on the density and an amount of density change.

[0095] In Example 13, the subject matter of any one or more of

Examples 3-12 optionally include, wherein: the memory is configured to store the scheduling parameter.

Θ096] In Example 14, the subject matter of any one or more of

Examples 1- 13 optionally include, wherein: the processing circuitry comprises a baseband processor, and the apparatus further comprises a transceiver configured to communicate with the other UE.

[0097] Example 15 is an apparatus of an evolved NodeB (eNB), the apparatus comprising: a memory: and processing circuitry in communication with the memory and arranged to: decode, from a UE through a direct (Xu-d) interface with the eNB, a sidelink report, the sidelink report comprising an indication of whether the UE supports communication with other UEs through a sidelink interface and a number of other UEs with which the UE communicates through the sidelink interface: determine a UE density in a coverage area of the eNB based on the sidelink report: and send, for transmission to the UE through the sidelink interface, at least one of: a value of a scheduling parameter to schedule communications between the UE and the other UEs, the scheduling parameter dependent on the UE density, or UE density information to adjust the scheduling parameter.

[0098] In Example 16, the subject matter of Example 15 optionally includes, wherein: the scheduling parameter comprises at least one of an efficiency of a modulation and coding scheme (MCS) used for pre-aliocation scheduling of communication with the other UEs, a maximum number of Physical Resource Allocations (PRAs) that are available to be scheduled by the UE, and a maximum number of retransmissions by the UE.

[0099] In Example 17, the subject matter of any one or more of Examples 15-16 optionally include, wherein: the value of the scheduling parameter is contained in a sidelink configuration transmitted to the UE in a Radio Resource Control (RRC) message.

[00100] In Example 18, the subject matter of any one or more of

Examples 15- 17 optionally include, wherein: the UE density information is contained in a sidelink configuration transmitted to the UE, the sidelink configuration free from the value for the scheduling parameter.

[00101 ] In Example 19, the subject matter of any one or more of

Examples 15-18 optionally include, wherein: the UE density information is contained in a sidelink density indicator (SDI) that indicates a change in the UE density.

[00102] In Example 20, the subject matter of Example 19 optionally includes, wherein: the SDI is transmitted from the eNB in downlink control information (DCI).

[00103] In Example 21 , the subject matter of any one or more of Examples 19-20 optionally include, wherein: the SDI is selected from an indication of: no change in the UE density to maintain the value of the scheduling parameter, an increase in the UE density to decrease the value of the scheduling parameter, and a decrease in the UE density to increase the value of the scheduling parameter.

[00104] In Example 22, the subject matter of Example 21 optionally includes, wherein: the SDI is further selected from an indication to reset the scheduling parameter to a default value.

[00105] In Example 23, the subject matter of any one or more of

Examples 19-22 optionally include, wherein: the indication in the SDI is dependent on the UE density and an amount of UE density change.

[00106] Example 24 is a computer-readable storage medium that stores instructions for execution by one or more processors of a user equipment (UE), the one or more processors to: generate a sidelink report comprising an indication of whether the UE supports communication with other UEs through a sidelink interface and a number of other UEs with which the UE communicates through the sidelink interface; transmit the sidelink report to an evolved NodeB (eNB) through a direct interface; in response to transmission of the sidelink report, receive sidelink information from the eNB, the sidelink information comprising at least one of a UE density in a coverage area of the eNB or a value of a scheduling parameter that is dependent on the UE density, the scheduling parameter comprising at least one of: an efficiency of a modulation and coding scheme (MCS) used for pre-allocation scheduling of communication with the other UE, a maximum number of Physical Resource Allocations (PRAs) that are available to be scheduled by the UE, and a maximum number of retra smissions by the UE; communicate with the other UEs through the sidelink interface based on the sidelink information.

[00107] In Example 25, the subject matter of Example 24 optionally includes, wherein: the sidelink information further comprises a sidelink density- indicator (SDI) that indicates a change in the UE density, and the instructions further cause the processor to: in response to an indication in the SDI of no change in the densit ', maintain the at least one of the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions, in response to an indication in the SDI of an increase in the density, decrease at least one of: the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions, and in response to an indication in the SDI of a decrease in the density, increase: at least one of the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions.

[00108] In Example 26, the subject matter of Example 25 optionally includes, wherein: the indication in the SDI is dependent on the UE density and an amount of density change.

[00109] Example 27 is an apparatus of a user equipment (UE), the apparatus comprising: means for generating a sidelink report comprising an indication of whether the UE supports communication with other UEs through a sidelink interface and a number of other UEs with which the UE communicates through the sidelink interface: means for transmitting the sidelink report to an evolved NodeB (eNB) through a direct interface; means for receiving, in response to transmission of the sidelink report, sidelink information from the eNB, the sidelink information comprising at least one of a UE density in a coverage area of the eNB or a value of a scheduling parameter that is dependent on the UE density, the scheduling parameter comprising at least one of: an efficiency of a modulation and coding scheme (MCS) used for pre-allocation scheduling of communication with the other UE, a maximum number of Physical Resource Allocations (PRAs) that are available to be scheduled by the UE, and a maximum number of retransmissions by the UE; means for communicating with the other UEs through the sidelink interface based on the sidelink information.

[00110] In Example 28, the subject matter of Example 27 optionally includes, wherein: the sidelink information further comprises a sidelink density indicator (SDI) that indicates a change in the UE density, and the apparatus further comprises: means for maintaining, in response to an indication in the SDI of no change in the density, the at least one of the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions, means for decreasing, in response to an indication in the SDI of an increase in the density, at least one of: the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions, and means for increasing, in response to an indication in the SDI of a decrease in the density: at least one of the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions. [00111] In Example 29, the subject matter of Example 28 optionally includes, wherein: the indication in the SDl is dependent on the UE density and an amount of density change.

[00112] Example 30 is a method of a user equipment (UE)

communicating with other UEs through a sidelink, the method comprising: generating a sidelink report comprising an indication of whether the UE supports communication with other UEs through a sidelink interface and a number of other UEs with which the UE communicates through the sidelink interface; transmitting the sidelink report to an evolved NodeB (eNB) through a direct interface; receiving, in response to transmission of the sidelink report, sidelink information from the eNB, the sidelink information comprising at least one of a UE density in a coverage area of the eNB or a value of a scheduling parameter that is dependent on the UE density, the scheduling parameter comprising at least one of: a efficiency of a modulation and coding scheme (MCS) used for pre-allocation scheduling of communication with the other UE, a maximum number of Physical Resource Allocations (PRAs) that are available to be scheduled by the UE, and a maximum number of retransmissions by the UE; communicating with the other UEs through the sidelink interface based on the sidelink information.

[00113] In Example 31, the subject matter of Example 30 optionally includes, wherein: the sidelink information further comprises a sidelink density indicator (SDT) that indicates a change in the UE density, and the method further comprises: maintaining, in response to an indication in the SDl of no change in the density, the at least one of the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions, decreasing, in response to an indication in the SDl of an increase in the density, at least one of: the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions, and increasing, in response to an indication in the SDl of a decrease in the density: at least one of the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions.

[00114] In Example 32, the subject matter of Example 31 optionally includes, wherein: the indication in the SDl is dependent on the UE density and an amount of density change. [00115] Although an embodiment has been described with reference to specific example embodiments, it will be evident that various modifications and changes may be made to these embodiments without departing from the broader scope of the present disclosure. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense. The

accompanying drawings that form a part hereof show, by way of illustration, and not of limitation, specific embodiments in which the subject matter may be practiced. The embodiments illustrated are described in sufficient detail to enable those skilled in the art to practice the teachings disclosed herein. Other embodiments may be utilized and derived therefrom, such that structural and logical substitutions and changes may be made without departing from the scope of this disclosure. This Detailed Description, therefore, is not to be taken in a limiting sense, and the scope of various embodiments is defined only by the appended claims, along with the full range of equivalents to which such claims are entitled.

[00116] The subject matter may be referred to herein, individually and/or collectively, by the term "embodiment" merely for convenience and without intending to voluntarily limit the scope of this application to any single inventive concept if more than one is in fact disclosed. Thus, although specific embodiments have been illustrated and described herein, it should be appreciated that any arrangement calculated to achieve the same purpose may be substituted for the specific embodiments shown. This disclosure is intended to cover any and all adaptations or variations of various embodiments. Combinations of the above embodiments, and other embodiments not specifically described herein, will be apparent to those of skill in the art upon reviewing the above description.

[00117] In this document, the terms "a" or "an" are used, as is common in patent documents, to include one or more than one, independent of any other instances or usages of "at least one" or "one or more." In this document, the term "or" is used to refer to a nonexclusive or, such that "A or B" includes "A but not B," "B but not A," and "A and B," unless otherwise indicated. In this document, the terms "including" and "in which" are used as the plain-English equivalents of the respective terms "comprising" and "wherein." Also, in the following claims, the terms "including" and "comprising" are open-ended, that is, a system, UE, article, composition, formulation, or process that includes elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms "first," "second," and "third," etc. are used merely as labels, and are not intended to impose numerical requirements on their objects.

[00118] The Abstract of the Disclosure is provided to comply with 37 C.F.R. § 1.72(b), requiring an abstract that will allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim . Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment.

Claims

CLAIMS What is claimed is:

1. An apparatus of a user equipment (UE), the apparatus comprising:

a memory; and

processing circuitry in communication with the memory and arranged to: encode, for transmission to an evolved NodeB (eNB) through a direct (Xu-d) interface, a sidelink report, the sidelink report comprising an indication of whether the UE supports communication with another

UE through a (Xu-s) sidelink interface;

after transmission of the sidelink report, decode sidelink information from the eNB, the sidelink information dependent on a density of at least UEs in communication with the eNB through the direct interface;

adjust a communication schedule between the UE and the other UE based on the sidelink information; and

send, for transmission to the other UE through the sidelink interface, at least one of control or data signals based on the

communication schedule ,

2. The apparatus of claim 1, wherein:

the sidelink report further comprises a number of other UEs with which the UE communicates through the sidelink interface, and

the density of at least UEs in communication with the eNB through a Xu- d interface further comprises UEs in communication, through a Xu-s interface, with one of the UEs in communication with the eNB through a Xu-d interface.

3. The apparatus of claim 1 or 2, wherein the processing circuitry is configured to:

adjust the communication schedule between the UE and the other UEs based on a scheduling parameter, the scheduling parameter comprising at least one of: an efficiency of a modulation and coding scheme (MCS) used for pre- ailocation scheduling of communication with the other UE, a maximum number of Physical Resource Allocations (PRAs) that are available to be scheduled by the UE, and a maximum number of retransmissions by the UE.

4. The apparatus of claim 3, wherein;

the sidelmk information comprises a sidelmk configuration that comprises values for the scheduling parameter.

5. The apparatus of claim 4, wherein:

the sidelmk configuration is received by the UE in a Radio Resource Control (RRC) message from the eNB.

6. The apparatus of claim 3, wherein:

the sidelmk information comprises a sidelmk configuration that comprises a density of UEs in a coverage area of the eNB, independent of whether the UEs are in direct communication with the eNB, and is free from values for the scheduling parameter, and

the processing circuitry is configured to determine the values for the scheduling parameter based on the density of UEs.

7. The apparatus of claim 3, wherein:

the sidelmk information comprises a sidelink density indicator (SDI) that indicates a change in the density of at least UEs in communication with the eNB through a Xu-d interface, and

the processing circuitry is configured to determine a change in values of the scheduling parameter based on the SDI,

8. The apparatus of claim 7, wherein:

the SDI is received from the eNB in downlink control information (DCI).

9. The apparatus of claim 7, wherein the processing circuitry is further configured to: in response to an indication in the SDI of no change in the density, maintain the at least one of the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions,

in response to an indication in the SDI of an increase in the density, decrease at least one of: the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions, and

in response to an indication in the SDI of a decrease in the density, increase: at least one of the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions.

10. The apparatus of claim 7, wherein the processing circuitry is further configured to:

in response to an indication in the SDI to reset the scheduling parameter, reset the at least one of the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions to a default value.

11. The apparatus of claim 7, wherein:

the SDI is received from the eNB in downlink control information (DCI).

12. The apparatus of claim 7, wherein:

the indication in the SDI is dependent on the density and an amount of density change.

13. The apparatus of claim 3, wherein:

the memory is configured to store the scheduling parameter.

14. The apparatus of claim 1 or 2, wherein:

the processing circuitry comprises a baseband processor, and

the apparatus further comprises a transceiver configured to communicate with the other UE.

15. An apparatus of an evolved NodeB (eNB), the apparatus comprising: a memory; and processing circuitry in communication with the memory and arranged to: decode, from a UE through a direct (Xu-d) interface with the eNB, a sidelink report, the sidelink report comprising an indication of whether the UE supports communication with other UEs through a sidelink interface and a number of other UEs with which the UE communicates through the sidelink interface;

determine a UE density in a coverage area of the eNB based on the sidelink report; and

send, for transmission to the UE through the sidelink interface, at least one of:

a value of a scheduling parameter to schedule communications between the UE and the other UEs, the scheduling parameter dependent on the UE density, or

UE density information to adjust the scheduling parameter.

16. The apparatus of claim 15, wherein:

the scheduling parameter comprises at least one of an efficiency of a modulation and coding scheme (MCS) used for pre-allocation scheduling of communication with the other UEs, a maximum number of Physical Resource Allocations (PRAs) that are available to be scheduled by the UE, and a maximum number of retransmissions by the UE.

17. The apparatus of claim 15 or 16, wherein:

the value of the scheduling parameter is contained in a sidelink configuration transmitted to the UE in a Radio Resource Control (RRC) message.

18. The apparatus of claim 15 or 6, wherein:

the UE density information is contained in a sidelink configuration transmitted to the UE, the sidelink configuration free from the value for the scheduling parameter.

19. The apparatus of claim 15 or 16, wherein:

the UE density information is contained in a sidelmk density indicator (SDI) that indicates a change in the UE density.

20. Hie apparatus of claim 19, wherein:

the SDI is transmitted from the eNB in downlink control information

(DCi),

21. The apparatus of claim 19, wherein:

the SDI is selected from, an indication of: no change in the UE density to maintain the value of the scheduling parameter, an increase in the UE density to decrease the value of the scheduling parameter, and a decrease in the UE density to increase the value of the scheduling parameter.

22. The apparatus of claim 21, wherein:

the SDI is further selected from an indication to reset the scheduling parameter to a default value.

23. The apparatus of claim 19, wherein:

the indication in the SDI is dependent on the UE density and an amount of UE density change.

24. A computer-readable storage medium that stores instructions for execution by one or more processors of a user equipment (UE), the one or more processors to:

generate a sidelink report comprising an indication of whether the UE supports communication with other UEs through a sidelink interface and a number of other U Es with which the UE communicates through the sidelink interface;

transmit the sidelink report to an evolved NodeB (eNB) through a direct interface:

in response to transmission of the sidelink report, receive sidelink information from the eNB, the sidelink information comprising at least one of a UE density in a coverage area of the eNB or a value of a scheduling parameter that is dependent on the UE density, the scheduling parameter comprising at least one of: an efficiency of a modulation and coding scheme (MCS) used for pre-a] location scheduling of communication with the other UE, a maximum number of Physical Resource Allocations (PRAs) that are available to be scheduled by the UE, and a maximum number of retransmissions by the U E; communicate with the other UEs through the sidelinJk interface based on the sidelink information.

25. The medium of claim 24, wherein:

the sidelink information further comprises a sidelink density indicator (SDI) that indicates a change in the UE density, and

the instructions further cause the processor to:

in response to an indication in the SDI of no change in the density, maintain the at least one of the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions,

in response to an indication in the SDI of an increase in the density, decrease at least one of: the MCS efficiency, the maximum number of PRAs, and the maximum number of retransmissions, and in response to an indication in the SDI of a decrease in the density, increase: at least one of the MCS efficiency, the maximum, number of PRAs, and the maximum number of retransmissions.

26. The medium of claim 25, wherein:

the indication in the SDI is dependent on the UE density and an amount of density change.