Patent Application
20230091891
The present disclosure relates generally to wireless communication systems and, more specifically, the present disclosure relates to orthogonal frequency-division multiplexing (OFDM) symbol adjustment for a configured sidelink (SL) transmission in a wireless communication system.
5th generation (5G) or new radio (NR) mobile communications is recently gathering increased momentum with all the worldwide technical activities on the various candidate technologies from industry and academia. The candidate enablers for the 5G/NR mobile communications include massive antenna technologies, from legacy cellular frequency bands up to high frequencies, to provide beamforming gain and support increased capacity, new waveform (e.g., a new radio access technology (RAT)) to flexibly accommodate various services/applications with different requirements, new multiple access schemes to support massive connections, and so on.
The present disclosure relates to wireless communication systems and, more specifically, the present disclosure relates to OFDM symbols adjustment for a configured SL transmission in a wireless communication system.
In one embodiment, a user equipment (UE) in a wireless communication system is provided. The UE includes a transceiver configured to receive a set of configurations and a processor operably coupled to the transceiver. The processor is configured to determine a set of time and frequency domain resources for at least one SL transmission based on the set of configurations; determine a duration for a cyclic prefix (CP) extension based on the set of configurations; and extend a first OFDM symbol of the at least one SL transmission for an interval preceding the first OFDM symbol with the duration for the CP extension. The transceiver is further configured to transmit the at least one SL transmission.
In another embodiment, a method of UE in a wireless communication system is provided. The method includes receiving a set of configurations, determining a set of time and frequency domain resources for at least one SL transmission based on the set of configurations, and determining a duration for a CP extension based on the set of configurations. The method further includes extending a first OFDM symbol of the at least one SL transmission for an interval preceding the first OFDM symbol with the duration for the CP extension and transmitting the at least one SL transmission.
Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims.
Before undertaking the DETAILED DESCRIPTION below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document. The term “couple” and its derivatives refer to any direct or indirect communication between two or more elements, whether or not those elements are in physical contact with one another. The terms “transmit,” “receive,” and “communicate,” as well as derivatives thereof, encompass both direct and indirect communication. The terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation. The term “or” is inclusive, meaning and/or. The phrase “associated with,” as well as derivatives thereof, means to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, have a relationship to or with, or the like. The term “controller” means any device, system, or part thereof that controls at least one operation. Such a controller may be implemented in hardware or a combination of hardware and software and/or firmware. The functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. The phrase “at least one of,” when used with a list of items, means that different combinations of one or more of the listed items may be used, and only one item in the list may be needed. For example, “at least one of: A, B, and C” includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A and B and C.
Moreover, various functions described below can be implemented or supported by one or more computer programs, each of which is formed from computer readable program code and embodied in a computer readable medium. The terms “application” and “program” refer to one or more computer programs, software components, sets of instructions, procedures, functions, objects, classes, instances, related data, or a portion thereof adapted for implementation in a suitable computer readable program code. The phrase “computer readable program code” includes any type of computer code, including source code, object code, and executable code. The phrase “computer readable medium” includes any type of medium capable of being accessed by a computer, such as read only memory (ROM), random access memory (RAM), a hard disk drive, a compact disc (CD), a digital video disc (DVD), or any other type of memory. A “non-transitory” computer readable medium excludes wired, wireless, optical, or other communication links that transport transitory electrical or other signals. A non-transitory computer readable medium includes media where data can be permanently stored and media where data can be stored and later overwritten, such as a rewritable optical disc or an erasable memory device.
Definitions for other certain words and phrases are provided throughout this patent document. Those of ordinary skill in the art should understand that in many if not most instances, such definitions apply to prior as well as future uses of such defined words and phrases.
For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts:
The following documents are hereby incorporated by reference into the present disclosure as if fully set forth herein: 3GPP TS 38.211 v.16.6.0, “Physical channels and modulation”; 3GPP TS 38.212 v.16.6.0, “Multiplexing and channel coding”; 3GPP TS 38.213 v16.6.0, “NR; Physical Layer Procedures for Control”; 3GPP TS 38.214: v.16.6.0, “Physical layer procedures for data”; and 3GPP TS 38.331 v.16.5.0, “Radio Resource Control (RRC) protocol specification.”
As shown in
The gNB 102 provides wireless broadband access to the network 130 for a first plurality of UEs within a coverage area 120 of the gNB 102. The first plurality of UEs includes a UE 111, which may be located in a small business; a UE 112, which may be located in an enterprise (E); a UE 113, which may be located in a WiFi hotspot (HS); a UE 114, which may be located in a first residence (R); a UE 115, which may be located in a second residence (R); and a UE 116, which may be a mobile device (M), such as a cell phone, a wireless laptop, a wireless PDA, or the like. The gNB 103 provides wireless broadband access to the network 130 for a second plurality of UEs within a coverage area 125 of the gNB 103. The second plurality of UEs includes the UE 115 and the UE 116. In various embodiments, a UE 116 may communicate with another UE 115 via a SL. For example, both UEs 115-116 can be within network coverage (of the same or different base stations). In another example, the UE 116 may be within network coverage and the other UE may be outside network coverage (e.g., UEs 111A-111C). In yet another example, both UE are outside network coverage. In some embodiments, one or more of the gNBs 101-103 may communicate with each other and with the UEs 111-116 using 5G/NR, LTE, LTE-A, WiMAX, WiFi, or other wireless communication techniques.
Depending on the network type, the term “base station” or “BS” can refer to any component (or collection of components) configured to provide wireless access to a network, such as transmit point (TP), transmit-receive point (TRP), an enhanced base station (eNodeB or eNB), a 5G/NR base station (gNB), a macrocell, a femtocell, a WiFi access point (AP), or other wirelessly enabled devices. Base stations may provide wireless access in accordance with one or more wireless communication protocols, e.g., 5G/NR 3rd generation partnership project (3GPP) NR, long term evolution (LTE), LTE advanced (LTE-A), high speed packet access (HSPA), Wi-Fi 802.11a/b/g/n/ac, etc. For the sake of convenience, the terms “BS” and “TRP” are used interchangeably in this patent document to refer to network infrastructure components that provide wireless access to remote terminals. Also, depending on the network type, the term “user equipment” or “UE” can refer to any component such as “mobile station,” “subscriber station,” “remote terminal,” “wireless terminal,” “receive point,” or “user device.” For the sake of convenience, the terms “user equipment” and “UE” are used in this patent document to refer to remote wireless equipment that wirelessly accesses a BS, whether the UE is a mobile device (such as a mobile telephone or smartphone) or is normally considered a stationary device (such as a desktop computer or vending machine).
Dotted lines show the approximate extents of the coverage areas 120 and 125, which are shown as approximately circular for the purposes of illustration and explanation only. It should be clearly understood that the coverage areas associated with gNBs, such as the coverage areas 120 and 125, may have other shapes, including irregular shapes, depending upon the configuration of the gNBs and variations in the radio environment associated with natural and man-made obstructions.
As described in more detail below, one or more of the UEs 111-116 include circuitry, programing, or a combination thereof, for OFDM symbols adjustment for a configured SL transmission in a wireless communication system. In certain embodiments, and one or more of the gNBs 101-103 includes circuitry, programing, or a combination thereof, for OFDM symbols adjustment for a configured SL transmission in a wireless communication system.
Although
As discussed in greater detail below, the wireless network 100 may have communications facilitated via one or more devices (e.g., UEs 111A to 111C) that may have a SL communication with the UEs 111. The UE 111 can communicate directly with the UEs 111A to 111C through a set of SLs (e.g., SL interfaces) to provide sideline communication, for example, in situations where the UEs 111A to 111C are remotely located or otherwise in need of facilitation for network access connections (e.g., BS 102) beyond or in addition to traditional fronthaul and/or backhaul connections/interfaces. In one example, the UE 111 can have direct communication, through the SL communication, with UEs 111A to 111C with or without support by the BS 102. Various of the UEs (e.g., as depicted by UEs 112 to 116) may be capable of one or more communication with their other UEs (such as UEs 111A to 111C as for UE 111).
As shown in
The RF transceivers 210a-210n receive, from the antennas 205a-205n, incoming RF signals, such as signals transmitted by UEs in the network 100. The RF transceivers 210a-210n down-convert the incoming RF signals to generate IF or baseband signals. The IF or baseband signals are sent to the RX processing circuitry 220, which generates processed baseband signals by filtering, decoding, and/or digitizing the baseband or IF signals. The RX processing circuitry 220 transmits the processed baseband signals to the controller/processor 225 for further processing.
The TX processing circuitry 215 receives analog or digital data (such as voice data, web data, e-mail, or interactive video game data) from the controller/processor 225. The TX processing circuitry 215 encodes, multiplexes, and/or digitizes the outgoing baseband data to generate processed baseband or IF signals. The RF transceivers 210a-210n receive the outgoing processed baseband or IF signals from the TX processing circuitry 215 and up-converts the baseband or IF signals to RF signals that are transmitted via the antennas 205a-205n.
The controller/processor 225 can include one or more processors or other processing devices that control the overall operation of the gNB 102. For example, the controller/processor 225 could control the reception of uplink channel signals and the transmission of downlink channel signals by the RF transceivers 210a-210n, the RX processing circuitry 220, and the TX processing circuitry 215 in accordance with well-known principles. The controller/processor 225 could support additional functions as well, such as more advanced wireless communication functions. For instance, the controller/processor 225 could support beam forming or directional routing operations in which outgoing/incoming signals from/to multiple antennas 205a-205n are weighted differently to effectively steer the outgoing signals in a desired direction. Any of a wide variety of other functions could be supported in the gNB 102 by the controller/processor 225.
The controller/processor 225 is also capable of executing programs and other processes resident in the memory 230, such as an OS. The controller/processor 225 can move data into or out of the memory 230 as by an executing process.
The controller/processor 225 is also coupled to the backhaul or network interface 235. The backhaul or network interface 235 allows the gNB 102 to communicate with other devices or systems over a backhaul connection or over a network. The interface 235 could support communications over any suitable wired or wireless connection(s). For example, when the gNB 102 is implemented as part of a cellular communication system (such as one supporting 5G/NR, LTE, or LTE-A), the interface 235 could allow the gNB 102 to communicate with other gNBs over a wired or wireless backhaul connection. When the gNB 102 is implemented as an access point, the interface 235 could allow the gNB 102 to communicate over a wired or wireless local area network or over a wired or wireless connection to a larger network (such as the Internet). The interface 235 includes any suitable structure supporting communications over a wired or wireless connection, such as an Ethernet or RF transceiver.
The memory 230 is coupled to the controller/processor 225. Part of the memory 230 could include a RAM, and another part of the memory 230 could include a Flash memory or other ROM.
Although
As shown in
The RF transceiver 310 receives, from the antenna 305, an incoming RF signal transmitted by a gNB of the network 100 or by other UEs (e.g., one or more of UEs 111-115) on a SL channel. The RF transceiver 310 down-converts the incoming RF signal to generate an intermediate frequency (IF) or baseband signal. The IF or baseband signal is sent to the RX processing circuitry 325, which generates a processed baseband signal by filtering, decoding, and/or digitizing the baseband or IF signal. The RX processing circuitry 325 transmits the processed baseband signal to the speaker 330 (such as for voice data) or to the processor 340 for further processing (such as for web browsing data).
The TX processing circuitry 315 receives analog or digital voice data from the microphone 320 or other outgoing baseband data (such as web data, e-mail, or interactive video game data) from the processor 340. The TX processing circuitry 315 encodes, multiplexes, and/or digitizes the outgoing baseband data to generate a processed baseband or IF signal. The RF transceiver 310 receives the outgoing processed baseband or IF signal from the TX processing circuitry 315 and up-converts the baseband or IF signal to an RF signal that is transmitted via the antenna 305.
The processor 340 can include one or more processors or other processing devices and execute the OS 361 stored in the memory 360 in order to control the overall operation of the UE 116. For example, the processor 340 could control the reception of downlink and/or SL channel signals and the transmission of uplink and/or SL channel signals by the RF transceiver 310, the RX processing circuitry 325, and the TX processing circuitry 315 in accordance with well-known principles. In some embodiments, the processor 340 includes at least one microprocessor or microcontroller.
The processor 340 is also capable of executing other processes and programs resident in the memory 360, such as processes for OFDM symbols adjustment for a configured SL transmission in a wireless communication system. The processor 340 can move data into or out of the memory 360 as required by an executing process. In some embodiments, the processor 340 is configured to execute the applications 362 based on the OS 361 or in response to signals received from gNBs or an operator. The processor 340 is also coupled to the I/O interface 345, which provides the UE 116 with the ability to connect to other devices, such as laptop computers and handheld computers. The I/O interface 345 is the communication path between these accessories and the processor 340.
The processor 340 is also coupled to the touchscreen 350 and the display 355. The operator of the UE 116 can use the touchscreen 350 to enter data into the UE 116. The display 355 may be a liquid crystal display, light emitting diode display, or other display capable of rendering text and/or at least limited graphics, such as from web sites.
The memory 360 is coupled to the processor 340. Part of the memory 360 could include a random access memory (RAM), and another part of the memory 360 could include a Flash memory or other read-only memory (ROM).
Although
To meet the demand for wireless data traffic having increased since deployment of 4G communication systems and to enable various vertical applications, 5G/NR communication systems have been developed and are currently being deployed. The 5G/NR communication system is considered to be implemented in higher frequency (mmWave) bands, e.g., 28 GHz or 60 GHz bands, so as to accomplish higher data rates or in lower frequency bands, such as 6 GHz, to enable robust coverage and mobility support. To decrease propagation loss of the radio waves and increase the transmission distance, the beamforming, massive multiple-input multiple-output (MIMO), full dimensional MIMO (FD-MIMO), array antenna, an analog beam forming, large scale antenna techniques are discussed in 5G/NR communication systems.
In addition, in 5G/NR communication systems, development for system network improvement is under way based on advanced small cells, cloud radio access networks (RANs), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, moving network, cooperative communication, coordinated multi-points (CoMP), reception-end interference cancellation and the like.
The discussion of 5G systems and frequency bands associated therewith is for reference as certain embodiments of the present disclosure may be implemented in 5G systems. However, the present disclosure is not limited to 5G systems or the frequency bands associated therewith, and embodiments of the present disclosure may be utilized in connection with any frequency band. For example, aspects of the present disclosure may also be applied to deployment of 5G communication systems, 6G or even later releases which may use terahertz (THz) bands.
A communication system includes a downlink (DL) that refers to transmissions from a base station or one or more transmission points to UEs and an uplink (UL) that refers to transmissions from UEs to a base station or to one or more reception points and an SL that refers to transmissions from one or more UEs to one or more UEs.
A time unit for DL signaling or for UL signaling on a cell is referred to as a slot and can include one or more symbols. A symbol can also serve as an additional time unit. A frequency (or bandwidth (BW)) unit is referred to as a resource block (RB). One RB includes a number of sub-carriers (SCs). For example, a slot can have duration of 0.5 milliseconds or 1 millisecond, include 14 symbols and an RB can include 12 SCs with inter-SC spacing of 30 KHz or 15 KHz, and so on.
DL signals include data signals conveying information content, control signals conveying DL control information (DCI), and reference signals (RS) that are also known as pilot signals. A gNB transmits data information or DCI through respective physical DL shared channels (PDSCHs) or physical DL control channels (PDCCHs). A PDSCH or a PDCCH can be transmitted over a variable number of slot symbols including one slot symbol. For brevity, a DCI format scheduling a PDSCH reception by a UE is referred to as a DL DCI format and a DCI format scheduling a physical uplink shared channel (PUSCH) transmission from a UE is referred to as an UL DCI format.
A gNB transmits one or more of multiple types of RS including channel state information RS (CSI-RS) and demodulation RS (DMRS). A CSI-RS is primarily intended for UEs to perform measurements and provide CSI to a gNB. For channel measurement, non-zero power CSI-RS (NZP CSI-RS) resources are used. For interference measurement reports (IMRs), CSI interference measurement (CSI-IM) resources associated with a zero power CSI-RS (ZP CSI-RS) configuration are used. A CSI process includes NZP CSI-RS and CSI-IM resources.
A UE can determine CSI-RS transmission parameters through DL control signaling or higher layer signaling, such as radio resource control (RRC) signaling, from a gNB. Transmission instances of a CSI-RS can be indicated by DL control signaling or be configured by higher layer signaling. A DMRS is transmitted only in the BW of a respective PDCCH or PDSCH and a UE can use the DMRS to demodulate data or control information.
The transmit path 400 as illustrated in
As illustrated in
The serial-to-parallel block 410 converts (such as de-multiplexes) the serial modulated symbols to parallel data in order to generate N parallel symbol streams, where N is the IFFT/FFT size used in the gNB 102 and the UE 116. The size N IFFT block 415 performs an IFFT operation on the N parallel symbol streams to generate time-domain output signals. The parallel-to-serial block 420 converts (such as multiplexes) the parallel time-domain output symbols from the size N IFFT block 415 in order to generate a serial time-domain signal. The add cyclic prefix block 425 inserts a cyclic prefix to the time-domain signal. The up-converter 430 modulates (such as up-converts) the output of the add cyclic prefix block 425 to an RF frequency for transmission via a wireless channel. The signal may also be filtered at baseband before conversion to the RF frequency.
A transmitted RF signal from the gNB 102 arrives at the UE 116 after passing through the wireless channel, and reverse operations to those at the gNB 102 are performed at the UE 116.
As illustrated in
Each of the gNBs 101-103 may implement a transmit path 400 as illustrated in
Each of the components in
Furthermore, although described as using FFT and IFFT, this is by way of illustration only and may not be construed to limit the scope of this present disclosure. Other types of transforms, such as discrete Fourier transform (DFT) and inverse discrete Fourier transform (IDFT) functions, can be used. It may be appreciated that the value of the variable N may be any integer number (such as 1, 2, 3, 4, or the like) for DFT and IDFT functions, while the value of the variable N may be any integer number that is a power of two (such as 1, 2, 4, 8, 16, or the like) for FFT and IFFT functions.
Although
In Rel-16 NR V2X, transmission and reception of SL signals and channels are based on resource pool(s) confined in the configured SL bandwidth part (BWP). In the frequency domain, a resource pool consists of a (pre-)configured number (e.g., sl-NumSubchannel) of contiguous sub-channels, wherein each sub-channel consists of a set of contiguous resource blocks (RBs) in a slot with size (pre-)configured by higher layer parameter (e.g., sl-SubchannelSize). In time domain, slots in a resource pool occur with a periodicity of 10240 ms, and slots including S-SSB, non-UL slots, and reserved slots are not applicable for a resource pool. The set of slots for a resource pool is further determined within the remaining slots, based on a (pre-)configured bitmap (e.g., sl-TimeResource). An illustration of a resource pool is shown in
Transmission and reception of physical sidelink shared channel (PSSCH), physical sidelink control channel (PSCCH), and physical sidelink feedback channel (PSFCH) are confined within and associated with a resource pool, with parameters (pre-)configured by higher layers (e.g., SL-PSSCH-Config, SL-PSCCH-Config, and SL-PSFCH-Config, respectively).
A UE may transmit the PSSCH in consecutive symbols within a slot of the resource pool, and PSSCH resource allocation starts from the second symbol configured for SL, e.g., startSLsymbol+1, and the first symbol configured for SL is duplicated from the second configured for SL, for AGC purpose. The UE may not transmit PSCCH in symbols not configured for SL, or in symbols configured for PSFCH, or in the last symbol configured for SL, or in the symbol immediately preceding the PSFCH. The frequency domain resource allocation unit for PSSCH is the sub-channel, and the sub-channel assignment is determined using the corresponding field in the associated SCI.
For transmitting a PSCCH, the UE can be provided a number of symbols (either 2 symbols or 3 symbols) in a resource pool (e.g., sl-TimResourcePSCCH) starting from the second symbol configured for SL, e.g., startSLsymbol+1; and further provided a number of RBs in the resource pool (e.g., sl-FreqResourcePSCCH) starting from the lowest RB of the lowest sub-channel of the associated PSSCH.
The UE can be further provided a number of slots (e.g., sl-PSFCH-Period) in the resource pool for a period of PSFCH transmission occasion resources, and a slot in the resource pool is determined as containing a PSFCH transmission occasion if the relative slot index within the resource pool is an integer multiple of the period of PSFCH transmission occasion. PSFCH is transmitted in two contiguous symbols in a slot, wherein the second symbol is with index startSLsymbols+lengthSLsymbols−2, and the two symbols are repeated. In frequency domain, PSFCH is transmitted in a single RB, wherein OCC can be possibly applied within the RB for multiplexing, and the location of the RB is determined based on an indication of a bitmap (e.g., sl-PSFCH-RB-Set), and the selection of PSFCH resource is according to the source ID and destination ID.
The first symbol including PSSCH and PSCCH is duplicated for AGC purpose. An illustration of the slot structure including PSSCH and PSCCH is shown in 701 of
In Rel-16 NR-U, cyclic prefix (CP) extension was supported for uplink transmissions. The time-continuous signal sext(p,μ)(t) for the interval tstart,lμ−Text≤t<tstart,lμ preceding the first OFDM symbol is given by sext(p,μ)(t)=
For a PUSCH transmission using configured grant, CP extension of the first uplink symbol was supported in order to construct intended gap duration for randomization of the transmission. The duration of the CP extension Text is given by Text=Σk=12
For SL operating on unlicensed spectrum, there is a need to adjust the duration of an OFDM symbol on SL, such that the gap between two transmissions can be controlled and randomness of the starting locations for transmission can be supported. In one example, the adjustment of a SL OFDM symbol can be a forward extension, e.g., CP extension, in order to shrink the gap from the previous transmission. In another example, the adjustment of a SL OFDM symbol can be a backward extension, in order to shrink the gap for the following transmission. In yet another example, the adjustment of a SL OFDM symbol can be a truncation from the starting of the symbol (e.g., AGC symbol). This disclosure focuses on the details of the SL OFDM duration adjustment for configured SL transmission and the indication of the adjustment.
In one embodiment, the examples of SL symbol adjustment covered in this disclosure can be applicable to at least one configured SL transmission. For one example, the configured SL transmission can be a PSSCH transmission configured by higher layer parameter. For another example, the configured SL transmission can be a PSFCH transmission. For yet another example, the configured SL transmission can be S-SS/PSBCH block transmission.
Various embodiments of the present disclosure focus on symbol duration adjustment for SL transmissions, including at least configured sidelink transmissions such as PSSCH, PSFCH, and S-SS/PSBCH block. More precisely, the present disclosure includes at least following components: (1) forward symbol extension for sidelink transmission; (2) backward symbol extension for sidelink transmission; (3) symbol truncation for sidelink transmission; (4) sidelink symbol adjustment indication, for example, (i) fixed symbol adjustment in specification and (ii) symbol adjustment indication by RRC parameter; and (5) sidelink and uplink symbol alignment.
In one embodiment, an OFDM symbol for sidelink transmission can be forward extended for a duration of Text. This can also be referred as CP extension.
In one example, the time-continuous signal sext(p,μ)(t) for the interval tstart,lμ−Text≤t<tstart,lμ preceding the sidelink OFDM symbol can be given by sext(p,μ)(t)=
An illustration of this example for forward symbol extension is shown in
In one example, for a configured sidelink transmission (e.g., configured PSSCH and/or PSFCH and/or S-SS/PSBCH block), the duration of the forward extension of a sidelink symbol (e.g., the first symbol of the sidelink transmission) can be given by Text=Σk=1F
In another example, for a configured sidelink transmission (e.g., configured PSSCH and/or PSFCH and/or S-SS/PSBCH block), the duration of the forward extension of a sidelink symbol (e.g., the first symbol of the sidelink transmission) can be given by Text=max(Σk=1F
In yet another example, for a configured sidelink transmission (e.g., configured PSSCH and/or PSFCH and/or S-SS/PSBCH block), the duration of the forward extension of a sidelink symbol (e.g., the first symbol of the sidelink transmission) can be given by Text=min(max(Σk=1F
In yet another example, for a configured sidelink transmission (e.g., configured PSSCH and/or PSFCH and/or S-SS/PSBCH block), the duration of the forward extension of a sidelink symbol (e.g., the first symbol of the sidelink transmission) can be given by Text=min (max (Σk=1F
In one example, the duration of the forward extension of a sidelink symbol can be supported for at least one of the following cases.
In a first case (e.g., case 0 in
In one variant of this case, the forward symbol extension can be symbol repetition(s). For instance, the first symbol of the scheduled sidelink transmission is repeated F0 times and transmitted proceeding the configured sidelink transmission.
In another case (e.g., case 1 in
In another case (e.g., case 2 in
In another case (e.g., case 3 in
In another case (e.g., case 4 in
In another case (e.g., case 5 in
In another case (e.g., case 6 in
In another case (e.g., case 7 in
In another example, the duration of the forward extension of a sidelink symbol can be supported for at least one of the following cases. In these cases, a timing difference ΔTTA can contribute to the determination of Text.
In another case (e.g., case 8 in
In another case (e.g., case 9 in
In another case (e.g., case 10 in
In another case (e.g., case 11 in
In another case (e.g., case 12 in
In another case (e.g., case 13 in
In another case (e.g., case 14 in
In another case (e.g., case 15 in
For ΔTTA in the above examples, it can include at least one of the following components: 1) the sidelink transmission is using a DL timing as its reference timing, and ΔTTA includes the sidelink timing difference TTA,SL=NTA,offset·TC, e.g., ΔTTA=TTA,SL; 2) the sidelink transmission is using a UL timing as its reference timing, and ΔTTA includes the timing difference between uplink and sidelink, e.g., ΔTTA=TTA,SL−TTA, wherein TTA is the timing advance of the uplink transmission; 3) the sidelink transmission is using another sidelink transmission as its reference timing, and ΔTTA includes the propagation delay between the two SL transmissions Tprop; 4) the reference timing of the sidelink transmission can have an asynchronous delay comparing to a common source (e.g., absolute timing), and ΔTTA can include such timing difference ΔTsync. In one instance, at least one component for ΔTTA can be configured by the gNB, and the UE applies such component when determining the value of ΔTTA. In another instance, at least one component for ΔTTA can be determined by the UE and applied by the UE when determining the value of ΔTTA.
F10
F11
F12
F13
F14
F15
In one embodiment, an OFDM symbol for sidelink transmission can be backward extended for a duration of
For one example, the time-continuous signal sext(p,μ)(t) for the interval tstart,lμ+Tsymb,lμ≤t<tstart,lμ+Tsymb,lμ+
For another example, the time-continuous signal sext(p,μ)(t) for the interval tstart,lμ+Tsymb,lμ≤t<tstart,lμ+Tsymb,lμ+
In one example, for a configured sidelink transmission (e.g., configured PSSCH and/or PSFCH and/or S-SS/PSBCH block), the duration of the backward extension of a sidelink symbol (e.g., the last symbol of the sidelink transmission) can be given by
In another example, for a configured sidelink transmission (e.g., configured PSSCH and/or PSFCH and/or S-SS/PSBCH block), the duration of the backward extension of a sidelink symbol (e.g., the first symbol of the sidelink transmission) can be given by
In yet another example, for a configured sidelink transmission (e.g., configured PSSCH and/or PSFCH and/or S-SS/PSBCH block), the duration of the backward extension of a sidelink symbol (e.g., the first symbol of the sidelink transmission) can be given by
In yet another example, for a configured sidelink transmission (e.g., configured PSSCH and/or PSFCH and/or S-SS/PSBCH block), the duration of the backward extension of a sidelink symbol (e.g., the first symbol of the sidelink transmission) can be given by
In one example, the duration of the backward extension of a sidelink symbol can be supported for at least one of the following cases, wherein in the examples, TTA,SL=NTA,offset·TC is the timing difference for sidelink transmissions comparing to its reference timing, and TTA is the timing advance for uplink transmission.
In another case (e.g., case 0 in
In another case (e.g., case 1 in
In one variant of this case, the backward symbol extension can be symbol repetition(s). For instance, the backward extension is using Example B of
In another case (e.g., case 2 in
In another case (e.g., case 3 in
In another case (e.g., case 4 in
In another case (e.g., case 5 in
In another case (e.g., case 6 in
For ΔATTA in the above examples, it can include at least one of the following components: 1) the sidelink transmission is using a DL timing as its reference timing, and ΔTTA includes the sidelink timing difference TTA,SL=NTA,offset·TC, e.g., ΔTTA=−TTA,SL; 2) the sidelink transmission is using a UL timing as its reference timing, and ΔTTA includes the timing difference between uplink and sidelink, e.g., ΔTTA=TTA−TTA,SL, wherein TTA is the timing advance of the uplink transmission; 3) the sidelink transmission is using another sidelink transmission as its reference timing, and ΔTTA includes the propagation delay between the two SL transmissions Tprop; 4) the reference timing of the sidelink transmission can have an asynchronuous delay comparing to a common source (e.g., absolute timing), and ΔTTA can include such timing difference ΔTsync. In one instance, at least one component for ΔTTA can be configured by the gNB, and the UE applies such component when determining the value of ΔTTA. In another instance, at least one component for ΔTTA can be determined by the UE and applied by the UE when determining the value of ΔTTA.
ext index i
In one embodiment, an OFDM symbol for sidelink transmission can be truncated from the starting of the symbol for a duration of Ttrunc. For instance, the symbol to be truncated can be the symbol for AGC purpose. For example, the time-continuous signal sextp,μ)(t) for the interval tstart,lμ≤t<tstart,lμ+Ttrunc for the first OFDM symbol is given by sext(p, μ)(t)=0, and an illustration of this example for symbol truncation is shown in
In one example, for a configured sidelink transmission (e.g., configured PSSCH and/or PSFCH and/or S-SS/PSBCH block), the duration of the truncation of a sidelink symbol (e.g., the first symbol of the sidelink transmission) can be given by Ttrunc=Δi−Σk−1H
In another example, for a configured sidelink transmission (e.g., configured PSSCH and/or PSFCH and/or S-SS/PSBCH block), the duration of the truncation of a sidelink symbol (e.g., the first symbol of the sidelink transmission) can be given by Ttrunc=min(max(Δi−Σk−1H
In one example, the duration of the symbol truncation of a sidelink symbol can be supported for at least one of the following cases.
In a first case (e.g., case 0 in
In another case (e.g., case 1 in
In another case (e.g., case 2 in
In another case (e.g., case 3 in
In another case (e.g., case 4 in
In another case (e.g., case 5 in
In another case (e.g., case 6 in
In another case (e.g., case 7 in
In another example, the duration of the symbol truncation of a sidelink symbol can be supported for at least one of the following cases.
In another case (e.g., case 8 in
In another case (e.g., case 9 in
In another case (e.g., case 10 in
In another case (e.g., case 11 in
In another case (e.g., case 12 in
In a fourteenth case (e.g., case 13 in
In another case (e.g., case 14 in
In another case (e.g., case 15 in
For ΔTTA in the above examples, it can include at least one of the following components: 1) the sidelink transmission is using a DL timing as its reference timing, and ΔTTA includes the sidelink timing difference TTA,SL=NTA,offset·TC, e.g., ΔTTA=−TTA,SL; 2) the sidelink transmission is using a UL timing as its reference timing, and ΔTTA includes the timing difference between uplink and sidelink, e.g., ΔTTA=TTA−TTA,SL, wherein TTA is the timing advance of the uplink transmission; 3) the sidelink transmission is using another sidelink transmission as its reference timing, and ΔTTA includes the propagation delay between the two SL transmissions Tprop; 4) the reference timing of the sidelink transmission can have an asynchronuous delay comparing to a common source (e.g., absolute timing), and ΔTTA can include such timing difference ΔTsync. In one instance, at least one component for ΔTTA can be configured by the gNB, and the UE applies such component when determining the value of ΔTTA. In another instance, at least one component for ΔTTA can be determined by the UE and applied by the UE when determining the value of ΔTTA.
H10
H11
H12
H13
H14
H15
In one embodiment, a UE can be indicated (explicitly or implicitly) with at least one of the cases for the sidelink symbol adjustment according to the mentioned embodiments/examples in the present disclosure.
In one approach, at least one of the cases for the sidelink symbol adjustment according to the mentioned embodiments/examples in the present disclosure can be supported for sidelink transmission, and the case(s) supported is fixed in the specification.
In one example, the support of fixed symbol adjustment is only for a sidelink with operation with shared spectrum channel access.
In one example, the support of fixed symbol adjustment can be for PSFCH.
In another example, the supported fixed symbol adjustment can be for S-SS/PSBCH block.
In one example, Case 0 of forward symbol extension can be supported for a configured sidelink transmission and fixed in the specification. For one sub-example, it is supported when the previous transmission is also a sidelink transmission from the same UE.
In another example, Case 1 of backward symbol extension can be supported for a configured sidelink transmission and fixed in the specification. For one sub-example, it is supported when the following transmission is also a sidelink transmission from the same UE.
In another approach, at least one of the cases for the sidelink symbol adjustment according to the mentioned embodiments/examples in the present disclosure can be supported for sidelink transmission, and the case(s) supported are indicated by higher layer parameters.
In one example, the support of symbol adjustment is only for a sidelink with operation with shared spectrum channel access.
In one example, a UE can be provided with at least one case of the forward symbol extension for sidelink transmissions by a RRC parameter.
In another example, a UE can be provided with one case of the backward symbol extension for sidelink transmissions by a RRC parameter.
In yet another example, a UE can be provided with at least one case of the forward symbol extension and/or symbol truncation for sidelink transmissions by a RRC parameter.
In one example, then a UE is performing a sidelink transmission with configured grants in a set of contiguous OFDM symbols on all resource blocks of an RB set, for the first such sidelink transmission, the UE determines a duration of sidelink symbol adjustment according to a case of the mentioned embodiments/examples in the present disclosure, wherein the index of the case can be chosen by the UE randomly from a set of values provided by higher layer parameters. In one sub-example, if the first such sidelink transmission is within a channel occupancy (e.g., initialized by a gNB or UE), the set of values can be determined as a first higher layer parameter associated with all resource blocks of an RB set. In another sub-example, if the first such sidelink transmission is not within a channel occupancy (e.g., initialized by a gNB or UE), the set of values can be determined as a second higher layer parameter associated with all resource blocks of an RB set.
In another example, then a UE is performing a sidelink transmission with configured grants in a set of contiguous OFDM symbols on fewer than all resource blocks of an RB set, for the first such sidelink transmission, the UE determines a duration of sidelink symbol adjustment according to a case of the mentioned embodiments/examples in the present disclosure, wherein the index of the case can be provided by higher layer parameters. In one sub-example, if the first such sidelink transmission is within a channel occupancy (e.g., initialized by a gNB or UE), the set of values can be determined as a first higher layer parameter associated with fewer than all resource blocks of an RB set. In another sub-example, if the first such sidelink transmission is not within a channel occupancy (e.g., initialized by a gNB or UE), the set of values can be determined as a second higher layer parameter associated with fewer than all resource blocks of an RB set.
In one embodiment, a sidelink transmission and a uplink transmission can be multiplexed and use the same symbol as the starting symbol of the transmission. For example, the sidelink transmission and the uplink transmission can be FDMed (e.g., mapped to different RBs) or IFDMed (e.g., mapped to different interlaces of RBs). For this embodiment, CP extension can be indicated and applied to the starting symbol for uplink transmission, and symbol adjustment (e.g., forward symbol extension and/or symbol truncation) can be indicated and applied to the starting symbol for sidelink transmission.
In one example, a UE is not expected to be dynamically scheduled (e.g., by a DCI and/or a SCI) with a sidelink transmission at a symbol that overlaps in time with a transmission occasion for a sidelink transmission with configured grant.
In another example, a UE is not expected to be dynamically scheduled (e.g., by a DCI and/or a SCI) with a sidelink transmission at a symbol that overlaps in time with a transmission occasion for a uplink transmission with configured grant.
In yet another example, a UE is not expected to be dynamically scheduled (e.g., by a DCI) with an uplink transmission at a symbol that overlaps in time with a transmission occasion for a sidelink transmission with configured grant.
In one example, a UE performs channel access procedures for the sidelink transmission and the uplink transmission separately (e.g., based on UE's capability), and the UE could be indicated with a first symbol duration adjustment (e.g., CP extension) for the sidelink transmission and a second CP extension for the uplink transmission.
In one sub-example, the UE expects the transmission starting time (e.g., with respect to DL timing) for the sidelink transmission and uplink transmission are aligned after applying the CP extensions respectively.
In another sub-example, if the starting time (e.g., with respect to DL timing) for the sidelink transmission and uplink transmission after applying the CP extensions respectively are not aligned, the UE can further extend the CP for the transmission with later starting time and align the starting time of the sidelink and uplink transmissions. For this sub-example, the UE may adjust the channel access procedure for the transmission with the later starting time to the same channel access procedure for the transmission with the earlier starting time.
In one example, a UE performs channel access procedure for the sidelink transmission and the uplink transmission jointly (e.g., based on UE's capability), and the UE could be indicated with a first symbol duration adjustment (e.g., CP extension) for the sidelink transmission and a second CP extension for the uplink transmission.
In one sub-example, the UE expects the transmission starting time (e.g., with respect to DL timing) for the sidelink transmission and uplink transmission are aligned after applying the CP extensions respectively.
In another sub-example, if the starting time (e.g., with respect to DL timing) for the sidelink transmission and uplink transmission after applying the CP extensions respectively are not aligned, the UE performs the joint channel access procedure before the earlier starting time of the transmission and start transmitting both slidelink and uplink transmissions if the channel access procedure completes.
The method 1700 begins with the UE receiving a set of configurations (step 1710). For example, in step 1710, the set of configurations may be provided by higher layer parameters or pre-configured. The UE then determines a set of time and frequency domain resources for at least one SL transmission based on the set of configurations (step 1720). For example, in step 1720, the at least one SL transmission may be a PSSCH, a physical PSFCH, or a S-SS/PSBCH block. The UE determines a duration for a CP extension based on the set of configurations (step 1730).
The UE then extends a first OFDM symbol of the at least one SL transmission for an interval preceding the first OFDM symbol with the duration for the CP extension (step 1740). For example, in step 1740, the interval preceding the first OFDM symbol may be given by tstart,lμ−Text≤t<tstart,lμ, tstart,lμ is a start instance of the first OFDM symbol, and Text=min(max(Σk−1F
In various embodiments, the UE may also determine a duration for a backward symbol extension based on the set of configurations and extend a last OFDM symbol of the at least one SL transmission for an interval succeeding the last OFDM symbol with the duration for the backward symbol extension. In this example, the interval succeeding the last OFDM symbol may be given by
Thereafter, the UE transmits the at least one SL transmission (step 1750). For example, in step 1750, the UE transmits the at least one SL transmission using the set of time and frequency domain resources and with the extension(s).
The above flowcharts and signaling flow diagrams illustrate example methods that can be implemented in accordance with the principles of the present disclosure and various changes could be made to the methods illustrated in the flowcharts herein. For example, while shown as a series of steps, various steps in each figure could overlap, occur in parallel, occur in a different order, or occur multiple times. In another example, steps may be omitted or replaced by other steps.
Although the present disclosure has been described with exemplary embodiments, various changes and modifications may be suggested to one skilled in the art. It is intended that the present disclosure encompass such changes and modifications as fall within the scope of the appended claims. None of the description in this application should be read as implying that any particular element, step, or function is an essential element that must be included in the claims scope. The scope of patented subject matter is defined by the claims.
The present application claims priority to U.S. Provisional Patent Application No. 63/247,640, filed on Sep. 23, 2021. The content of the above-identified patent document is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 63247640 | Sep 2021 | US |
