Slot format for sidelink communications

Abstract

Certain aspects of the present disclosure provide techniques for a time slot format for sidelink communications. A method that can be performed by a user equipment (UE) includes: suppressing transmission during a slot portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a slot portion and a signal portion; transmitting a signal during the signal portion of the first symbol; and transmitting a data signal for the sidelink transmission in at least one second symbol in time after the first symbol in the sidelink transmission.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of and priority to Greek Application No. 20200100365, filed on June 24, 2020, which is incorporated herein by reference in its entirety for all applicable purposes. Technical Field

[0003] Aspects of the present disclosure relate to wireless communications and, more particularly, to techniques for sidelink communications. Background Art

[0004] Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, broadcast, etc. These wireless communication systems may employ multiple access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, etc.). Examples of such multiple access systems include 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) systems, Advanced LTE (LTE-A) systems, Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, Single Carrier Frequency Division Multiple Access (SC-FDMA) systems, and Time Division Synchronous Code Division Multiple Access (TD-SCDMA) systems, to name just a few.

[0005] These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate at a city, country, region, or even global level. New radio (e.g., 5G NR) is an example of an emerging telecommunication standard. NR is a set of enhancements to the LTE mobile standard released by 3GPP. NR is designed to better support mobile broadband Internet access by improving spectral efficiency, reducing costs, improving services, utilizing new spectrum, and better integrating with other open standards using OFDMA with cyclic prefix (CP) on downlink (DL) and uplink (UL). To this end, NR supports beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation.

[0006] However, as the demand for mobile broadband access continues to grow, further improvements to NR and LTE technologies are needed. Preferably, these improvements should be applicable to other multi-access technologies and the telecommunication standards that adopt these technologies. Summary of the invention

[0007] The systems, methods, and devices of the present disclosure each have several aspects, no single aspect of which is solely responsible for its desirable attributes. Without limiting the scope of the present disclosure as expressed by the appended claims, some features will now be briefly discussed. After considering this discussion, and particularly after reading the section entitled "Detailed Description of the Invention," one will understand how the features of the present disclosure provide sidelink communications in an unlicensed spectrum.

[0008] Certain aspects of the subject matter described in the present disclosure may be implemented in a method for wireless communication by a user equipment (UE). The method generally includes suppressing transmission during a gap portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion; transmitting a signal during the signal portion of the first symbol; and transmitting a data signal for the sidelink transmission in at least one second symbol in time after the first symbol in the sidelink transmission. In some aspects, the signal is an automatic gain control (AGC) signal.

[0009] Certain aspects of the subject matter described in the present disclosure may be implemented in a method for wireless communication by a user equipment (UE). The method generally includes: receiving a signal during a signal portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion after the gap portion; and receiving a data signal of the sidelink transmission in at least one second symbol in time after the first symbol in the sidelink transmission. In some aspects, the signal is an automatic gain control (AGC) signal.

[0010] Certain aspects of the subject matter described in the present disclosure can be implemented in an apparatus for wireless communication. The apparatus generally includes a component for suppressing transmission during a gap portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion; a component for transmitting a signal during the signal portion of the first symbol; and a component for transmitting a data signal of the sidelink transmission in at least one second symbol in time after the first symbol in the sidelink transmission. In some aspects, the signal is an automatic gain control (AGC) signal.

[0011] Certain aspects of the subject matter described in the present disclosure can be implemented in an apparatus for wireless communication. The apparatus generally includes a component for receiving a signal during a signal portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion after the gap portion; and a component for receiving a data signal of the sidelink transmission in at least one second symbol in time after the first symbol in the sidelink transmission. In some aspects, the signal is an automatic gain control (AGC) signal.

[0012] Certain aspects of the subject matter described in the present disclosure may be implemented in an apparatus for wireless communication. The apparatus generally includes a memory and a processor coupled to the memory. The memory and the processor are configured to suppress transmission during a gap portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion; transmit a signal during the signal portion of the first symbol; and transmit a data signal of the sidelink transmission in at least one second symbol in time after the first symbol in the sidelink transmission. In some aspects, the signal is an automatic gain control (AGC) signal.

[0013] Certain aspects of the subject matter described in the present disclosure can be implemented in a device for wireless communication. The device generally includes a memory and a processor coupled to the memory. The memory and the processor are configured to receive a signal during a signal portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion after the gap portion; and receive a data signal of the sidelink transmission in at least one second symbol in time after the first symbol in the sidelink transmission. In some aspects, the signal is an automatic gain control (AGC) signal.

[0014] Certain aspects of the subject matter described in the present disclosure may be implemented in a computer-readable medium for wireless communication. The medium includes instructions that, when executed by a processing system, cause the processing system to perform operations that generally include: suppressing transmission during a gap portion of a first symbol in time for a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion; transmitting a signal during the signal portion of the first symbol; and transmitting a data signal for the sidelink transmission in at least one second symbol that is temporally subsequent to the first symbol in the sidelink transmission. In some aspects, the signal is an automatic gain control (AGC) signal.

[0015] Certain aspects of the subject matter described in the present disclosure may be implemented in a computer-readable medium for wireless communication. The medium includes instructions that, when executed by a processing system, cause the processing system to perform operations that generally include: receiving a signal during a signal portion of a first symbol in time for a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion after the gap portion; and receiving a data signal for the sidelink transmission in at least one second symbol in time after the first symbol in the sidelink transmission. In some aspects, the signal is an automatic gain control (AGC) signal.

[0016] To achieve the foregoing and related ends, one or more aspects include features fully described below and particularly pointed out in the claims. The following description and the accompanying drawings set forth in detail certain illustrative features of one or more aspects. However, these features are only indicative of a few of the various ways in which the principles of the various aspects can be employed. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to be able to understand the above-mentioned features of the present disclosure in detail, a more specific description may be made with reference to some aspects, some of which are shown in the accompanying drawings. However, it should be noted that the accompanying drawings only illustrate certain aspects of the present disclosure and are therefore not to be considered as limiting the scope of the present disclosure, as the description may admit other equally effective aspects.

[0018] Figure 1 is a block diagram conceptually illustrating an example wireless communication network in accordance with certain aspects of the present disclosure.

[0019] Figure 2 is a block diagram conceptually illustrating designs of example base stations (BSs) and user equipment (UEs) in accordance with certain aspects of the present disclosure.

[0020] Figure 3 is an example frame format for certain wireless communication systems (e.g., New Radio (NR)) in accordance with certain aspects of the present disclosure.

[0021] Figure 4A and Figure 4B A diagram of an example Vehicle-to-Everything (V2X) system is shown in accordance with certain aspects of the present disclosure.

[0022] Figure 5 is a diagram illustrating an example model of multiple wireless devices operating in an unlicensed spectrum in accordance with certain aspects of the present disclosure.

[0023] Fig. 6A and Figure 6B is an example transmission timeline for sidelink communications in accordance with certain aspects of the present disclosure.

[0024] Fig. 7A and Figure 7B is an example transmission timeline for sidelink communications in accordance with certain aspects of the present disclosure.

[0025] Figure 8 is a flow chart illustrating example operations of a UE conducting wireless communications in accordance with certain aspects of the present disclosure.

[0026] Fig. 9 is a flow chart illustrating example operations of a UE conducting wireless communications in accordance with certain aspects of the present disclosure.

[0027] Figure 10A-10E is an example transmission timeline with a gap period and an AGC signal in the first symbol of a time slot in accordance with certain aspects of the present disclosure.

[0028] Fig.11 A method according to various aspects of the present disclosure may include a method configured to perform Figure 8The operation of the various components of a communication device.

[0029] Fig.12 A method according to various aspects of the present disclosure may include a method configured to perform Fig. 9 The operation of the various components of a communication device.

[0030] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one aspect may be beneficially utilized on other aspects without specific recitation. DETAILED DESCRIPTION

[0031] Various aspects of the present disclosure provide apparatus, methods, processing systems, and computer-readable media having a transmission scheme for sidelink communications that allows a UE and / or other UEs to transmit on a channel without performing a channel access procedure. Example sidelink communications include vehicle-to-everything (V2X) communications. Although certain aspects may be discussed with respect to V2X communications in a V2X communication system, it should be noted that these aspects may be equally applicable to other suitable types of sidelink communication systems.

[0032] In certain aspects, for wireless communications in an unlicensed spectrum, a wireless communication device (e.g., a UE and / or a Wi-Fi device) may perform a channel access procedure known as a listen-before-talk (LBT) procedure, wherein the device may transmit if a channel corresponding to a frequency band is sensed to be idle (e.g., idle) prior to transmission. The time period prior to transmission in which the LBT procedure is performed may be referred to as a sensing opportunity. In the LBT procedure, the wireless communication device measures the energy on the frequency band, and if the frequency band is busy, suppresses transmission on the frequency band, and if the frequency band is idle, determines that the wireless communication device may communicate on the frequency band. As used herein, the term "idle" for a frequency band means that the energy measured on the frequency band by the device that determines that it is idle is below a threshold level. As used herein, the term "busy" for a frequency band means that the energy measured on the frequency band by the device that determines that it is idle is above a threshold level. This energy may be due to noise or signals within the frequency band.

[0033] In some aspects, a device may perform an LBT process on an unlicensed band before transmitting a signal on the unlicensed band if the time period since the device previously transmitted on the unlicensed band (e.g., a gap in transmission) is greater than a particular threshold (e.g., 16 μs).

[0034] In some aspects, sidelink communications may be scheduled with gap time periods (e.g., gap symbols in a time slot) during which the UE does not transmit or does not receive. In some aspects, the gap time periods may be referred to as gap symbols. The gap symbols may enable the UE to switch from a receive mode to a transmit mode, and vice versa. The gap symbols may also take into account delayed signal communications, such as propagation delays due to UEs being out of sync in time.

[0035] In certain aspects, the sidelink communication may also be scheduled with at least one time period for automatic gain control (AGC) (e.g., an AGC symbol in a time slot), wherein the transmitting UE may send a signal to the receiving UE to enable the receiving UE to adjust the gain applied to the signal received from the transmitting UE. Such a time period may be referred to as an AGC symbol. In certain aspects, the AGC symbol may be arranged in the first symbol in time in the time slot, and the gap symbol may be arranged in the last symbol in time in the time slot. With this arrangement, some UEs may suppress transmission within at least two consecutive symbols due to a gap in the transmission from the UE exceeding a threshold duration, which may trigger the UE to perform LBT before transmitting.

[0036] Certain aspects of the present disclosure provide techniques and / or devices for symbol arrangement for sidelink communications, which allow a UE to transmit on a channel without performing a channel access procedure. For example, in some aspects, a symbol in a time slot may include a gap portion and a signal portion, the gap portion may be used for transmission mode switching and / or to account for propagation delays in sidelink communications, and the signal portion may be used, for example, for AGC tuning. The duration of the gap portion may be less than a threshold value (e.g., 16 μs, 25 μs, etc.), which may be used to trigger an LBT process in some cases. In other words, the duration of the signal portion in the symbol may be such that the gap portion has a duration less than a threshold value. For example, if the gap portion duration is less than a threshold value, the UE may transmit after the gap portion without performing a channel access procedure. In some cases, the UE may perform a channel access procedure before transmitting after the gap portion, which may allow the UE to share channel resources with another UE. Various aspects of the present disclosure may achieve sidelink communication performance, such as lower latency and / or higher data rates, for example, due to the ability to transmit data signals after the gap portion without performing LBT or other channel sensing.

[0037] This technology can be used, for example, for sidelink communications between wireless communication devices. In other examples, the wireless communication devices can include cellular carrier-to-everything (CV2X) devices. It should be noted that although certain aspects are described with respect to CV2X devices and communications in unlicensed bands, it should be understood that these aspects can be similarly applicable to other scenarios, such as any communication in an unlicensed band (e.g., sidelink communications), communications in a licensed band (e.g., sidelink communications), etc.

[0038] Unlicensed bands in the unlicensed spectrum are any frequency bands that are not licensed for use under regulatory practices, making them open for use by any device, not just those licensed to use a particular band.

[0039] The electromagnetic spectrum, such as in licensed frequency bands, is typically subdivided into various classes, bands, channels, etc. based on frequency / wavelength. In 5G NR, two initial operating bands are identified as frequency range designations FR1 (410 MHz–7.125 GHz) and FR2 (24.25 GHz–52.6 GHz). It should be understood that although a portion of FR1 is greater than 6 GHz, FR1 is often referred to (interchangeably) as a “sub-6 GHz” band in various literature and articles. A similar naming issue sometimes arises for FR2, which is often referred to (interchangeably) as a “millimeter wave” band in literature and articles, although it is different from the extremely high frequency (EHF) band (30 GHz–300 GHz) identified as a “millimeter wave” band by the International Telecommunication Union (ITU).

[0040] Frequencies between FR1 and FR2 are often referred to as mid-band frequencies. Recent 5G NR research has identified operating bands for these mid-band frequencies as frequency range designation FR3 (7.125 GHz–24.25 GHz). Frequency bands falling into FR3 may inherit FR1 characteristics and / or FR2 characteristics, and thus may effectively extend the characteristics of FR1 and / or FR2 into the mid-band frequencies. In addition, higher frequency bands are currently being explored to extend 5G NR operations above 52.6 GHz. For example, three higher operating bands have been identified as frequency range designations FR4a or FR4-1 (52.6 GHz–71 GHz), FR4 (52.6 GHz–114.25 GHz), and FR5 (114.25 GHz–300 GHz). Each of these higher frequency bands falls into the EHF band.

[0041] In view of the above, unless otherwise stated, it should be understood that the term "sub-6 GHz" and the like, if used herein, can broadly refer to frequencies below 6 GHz, can be within FR1, or can include mid-band frequencies. In addition, unless otherwise stated, it should be understood that the term "millimeter wave" and the like, if used herein, can broadly refer to frequencies that can include mid-band frequencies; can be within FR2, FR4, FR4-a or FR4-1 and / or FR5; or can be within the EHF band.

[0042] The following description provides an example of suppressing transmission during the gap portion of a symbol, transmitting or receiving an automatic gain control (AGC) signal during the AGC portion of a symbol, and transmitting or receiving a data signal in a communication system, and does not limit the scope, applicability, or examples set forth in the claims. Without departing from the scope of the present disclosure, the functions and arrangements of the elements discussed may be changed. Various examples may appropriately omit, replace, or add various processes or components. For example, the described method may be performed in an order different from that described, and various steps may be added, omitted, or combined. In addition, the features described for some examples may be combined in some other examples. For example, any number of aspects set forth herein may be used to implement a device or practice method. In addition, the scope of the present disclosure is intended to cover such a device or method that is practiced using other structures, functions, or structures and functions in addition to or different from the various aspects of the present disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of a claim. The word "exemplary" is used herein to mean "used as an example, instance, or illustration". Any aspect described as "exemplary" herein is not necessarily to be interpreted as being superior or more advantageous than other aspects.

[0043] Generally, any number of wireless networks can be deployed in a given geographic area. Each wireless network can support a specific radio access technology (RAT) and can operate on one or more frequencies. RAT can also be referred to as radio technology, air interface, etc. Frequency can also be referred to as carrier, subcarrier, channel, frequency tone, subband, etc. Each frequency can support a single RAT in a given geographic area to avoid interference between wireless networks of different RATs.

[0044] The techniques described herein can be used for various wireless networks and radio technologies. Although various aspects may be described herein using terms typically associated with 3G, 4G, and / or new radio (e.g., 5G NR) wireless technologies, various aspects of the present disclosure may be applied to other communication systems based on generations.

[0045] NR access can support various wireless communication services, such as enhanced mobile broadband (eMBB) targeting wide bandwidth (e.g., 80 MHz or above), millimeter wave (mmW) targeting high carrier frequency (e.g., 24 GHz to 53 GHz or above), massive machine type communication MTC (mMTC) targeting non-backward compatible MTC technology, and / or mission-critical communication targeting ultra-reliable low latency communication (URLLC). These services may include latency and reliability requirements. These services may also have different transmission time intervals (TTIs) to meet their respective quality of service (QoS) requirements. In addition, these services can coexist in the same subframe. NR supports beamforming and the beam direction can be dynamically configured. MIMO transmission with precoding can also be supported. The MIMO configuration in DL can support up to 8 transmit antennas, multi-layer DL transmission with up to 8 streams and up to 2 streams per UE. Multi-layer transmission of up to 2 streams per UE can be supported. Aggregation of multiple cells of up to 8 serving cells can be supported.

[0046] Figure 1 An example wireless communication network 100 is shown in which aspects of the present disclosure may be performed. For example, the wireless communication network 100 may be a NR system (e.g., a 5G NR network). Figure 1 As shown, the wireless communication network 100 may communicate with a core network 132. The core network 132 may communicate with one or more base stations (BSs) 110 and / or user equipments (UEs) 120 in the wireless communication network 100 via one or more interfaces.

[0047] According to certain aspects, BS 110 and UE 120 may be configured to use a time slot format for sidelink communications, such as reference Figure 3 Further discussion. Figure 1 As shown, according to various aspects of the present disclosure, UE 120a includes a side link manager 122 that suppresses transmission during a gap portion of a first symbol of a time slot, wherein the first symbol includes a gap portion and a signal portion; transmits a signal during the signal portion of the first symbol; and transmits a data signal for side link transmission in at least one second symbol after the first symbol in the time slot. According to various aspects of the present disclosure, UE 120b includes a side link manager 124 that detects a gap portion of a first symbol of a time slot, wherein the first symbol includes a gap portion and a signal portion; receives a signal during the signal portion of the first symbol; and receives a data signal for side link transmission in at least one second symbol after the first symbol in the time slot.

[0048] like Figure 1As shown, the wireless communication network 100 may include multiple base stations 110a-110z (each base station is also referred to herein individually as a base station 110 or collectively as base stations 110) and other network entities. BS 110 can provide communication coverage for a specific geographic area (sometimes referred to as a "cell"), which can be fixed or can move according to the location of the mobile BS 110. In some examples, BS 110 can be interconnected with each other and / or with one or more other BSs or network nodes (not shown) in the wireless communication network 100 using any suitable transport network and through various types of backhaul interfaces (e.g., direct physical connections, wireless connections, virtual networks, etc.). Figure 1 In the example shown, base stations 110a, 110b, and 110c may be macro base stations for macro cells 102a, 102b, and 102c, respectively. BS 110x may be a pico BS for pico cell 102x. Base stations 110y and 110z may be femto base stations for femto cells 102y and 102z, respectively. A BS may support one or more cells.

[0049] BS 110 communicates with UE 120a-120y (each also individually referred to as UE 120 or collectively referred to as UE 120 herein) in the wireless communication network 100. UE 120 (e.g., 120x, 120y, etc.) can be dispersed in the wireless communication network 100, and each UE 120 can be fixed or mobile. In one example, a quadcopter, a drone, or any other unmanned aerial vehicle (UAV) or a remotely piloted aerial system (RPAS) 120d can be configured to serve as a UE. The wireless communication network 100 may also include a relay station (e.g., a relay station 110r) (which is also referred to as a relay, etc.), which receives transmissions of data and / or other information from an upstream station (e.g., BS 110a or UE 120r) and sends transmissions of data and / or other information to a downstream station (e.g., UE 120 or BS 110), or relays transmissions between UE 120 to facilitate communication between devices.

[0050] The network controller 130 may communicate with a set of BSs 110 and provide coordination and control (e.g., via a backhaul) for these BSs 110. In some aspects, the network controller 130 may communicate with a core network 132 (e.g., a 5G core network (5GC)), which provides various network functions such as access and mobility management, session management, user plane functions, policy control functions, authentication server functions, unified data management, application functions, network exposure functions, network repository functions, network slice selection functions, etc.

[0051] Figure 2 BS 110a and UE 120a (eg, Figure 1 Example components of a wireless communication network 100) that can be used to implement aspects of the present disclosure.

[0052] At BS 110a, transmit processor 220 may receive data from data source 212 and control information from controller / processor 240. Control information may be for a physical broadcast channel (PBCH), a physical control format indicator channel (PCFICH), a physical hybrid ARQ indicator channel (PHICH), a physical downlink control channel (PDCCH), a group common PDCCH (GC PDCCH), etc. Data may be for a physical downlink shared channel (PDSCH), etc. A medium access control (MAC)-control element (MAC-CE) is a MAC layer communication structure that may be used for control command exchange between wireless nodes. A MAC-CE may be carried in a shared channel such as a physical downlink shared channel (PDSCH), a physical uplink shared channel (PUSCH), or a physical sidelink shared channel (PSSCH).

[0053] The processor 220 may process (e.g., encode and symbol map) data and control information to obtain data symbols and control symbols, respectively. The transmit processor 220 may also generate reference symbols such as for a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a PBCH demodulation reference signal (DMRS), and a channel state information reference signal (CSI-RS). The transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on ​​data symbols, control symbols, and / or reference symbols (if applicable), and may provide an output symbol stream to a modulator (MOD) 232a-232t. Each modulator 232 may process its own output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each modulator may further process (e.g., convert to analog, amplify, filter, and up-convert) the output sample stream to obtain a downlink signal. The downlink signals from modulators 232a-232t may be transmitted via antennas 234a-234t, respectively.

[0054] At UE 120a, antennas 252a-252r can receive downlink signals from BS 110a and can provide received signals to demodulators (DEMODs) in transceivers 254a-254r, respectively. Each demodulator 254 can adjust (e.g., filter, amplify, downconvert and digitize) the respective received signals to obtain input samples. Each demodulator can further process the input samples (e.g., for OFDM, etc.) to obtain received symbols. MIMO detector 256 can obtain received symbols from all demodulators 254a-254r, perform MIMO detection on the received symbols (if applicable) and provide detected symbols. Receive processor 258 can process (e.g., demodulate, deinterleave and decode) the detected symbols, provide decoded data of UE 120a to data sink 260 and provide decoded control information to controller / processor 280.

[0055] On the uplink, at the UE 120a, a transmit processor 264 may receive and process data from a data source 262 (e.g., for a physical uplink shared channel (PUSCH)) and control information from a controller / processor 280 (e.g., for a physical uplink control channel (PUCCH)). The transmit processor 264 may also generate reference symbols for reference signals (e.g., a sounding reference signal (SRS)). The symbols from the transmit processor 264 may be precoded by a TX MIMO processor 266 (if applicable), further processed by a modulator in a transceiver 254a-254r (e.g., for SC-FDM, etc.), and transmitted to the BS 110a. At the BS 110a, the uplink signal from the UE 120a may be received by the antenna 234, processed by the modulator 232, detected by the MIMO detector 236 (if applicable), and further processed by the receive processor 238 to obtain decoded data and control information transmitted by the UE 120a. Receive processor 238 may provide decoded data to a data sink 239 and decoded control information to controller / processor 240 .

[0056] Memories 242 and 282 may store data and program codes for BS 110a and UE 120a, respectively.A scheduler 244 may schedule UEs for data transmission on the downlink and / or uplink.

[0057] The antennas 252, processors 266, 258, 264 and / or controller / processor 280 of the UE 120a and / or the antennas 234, processors 220, 230, 238 and / or controller / processor 240 of the BS 110a may be used to perform the various techniques and methods described herein. Figure 2As shown, the controller / processor 280 of UE 120a has a side link manager 281, which suppresses transmission during the gap portion of the first symbol of the time slot, wherein the first symbol includes a gap portion and a signal portion; transmits a signal during the signal portion of the first symbol; and transmits a data signal for side link transmission in at least one second symbol after the first symbol in the time slot. The side link manager 281 also detects the gap portion of the first symbol of the time slot, wherein the first symbol includes a gap portion and a signal portion; receives a signal during the signal portion of the first symbol; and receives a data signal for side link transmission in at least one second symbol after the first symbol in the time slot. Although shown at the controller / processor, other components of UE 120a and BS 110a may be used to perform the operations described herein.

[0058] NR can utilize orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) on the uplink and downlink. NR can support half-duplex operation using time division duplex (TDD). OFDM and single carrier frequency division multiplexing (SC-FDM) divide the system bandwidth into multiple orthogonal subcarriers, which are also commonly referred to as frequency modulation, frequency bins, etc. Each subcarrier can be modulated with data. Modulation symbols can be sent in the frequency domain using OFDM and in the time domain using SC-FDM. The spacing between adjacent subcarriers can be fixed, and the total number of subcarriers can depend on the system bandwidth. The minimum resource allocation, called a resource block (RB), can be 12 consecutive subcarriers. The system bandwidth can also be divided into subbands. For example, a subband can cover multiple RBs. NR can support a base subcarrier spacing (SCS) of 15KHz, and other SCSs (e.g., 30kHz, 60kHz, 120kHz, 240kHz, etc.) can be defined relative to the base SCS.

[0059] Figure 3300 is a diagram showing an example of a frame format for NR. The transmission timeline for each of the downlink and uplink may be divided into units of radio frames. Each radio frame may have a predetermined duration (e.g., 10 ms) and may be divided into 10 subframes, each of 1 ms, indexed from 0 to 9. Depending on the SCS, each subframe may include a variable number of slots (e.g., 1, 2, 4, 8, 16 ... slots). Depending on the SCS, each slot may include a variable number of symbol periods (e.g., 7, 12, or 14 symbols). The symbol period in each slot may be assigned an index. A microslot, which may be referred to as a subslot structure, refers to a transmission time interval (e.g., 2, 3, or 4 symbols) with a duration less than one slot. Each symbol in a slot may indicate a link direction (e.g., DL, UL, or flexible) for data transmission, and the link direction of each subframe may be dynamically switched. The link direction may be based on the slot format. Each slot may include DL / UL data and DL / UL control information. In some aspects, two symbols (e.g., the first two in time) of a time slot of the frame format 300 can be configured or used for communication as discussed herein. For example, the first symbol can include a slot portion and a signal portion. In addition, a data signal can be sent on the second symbol.

[0060] In NR, synchronization signal blocks (SSBs) are transmitted. In certain aspects, SSBs may be transmitted in bursts, where each SSB in the burst corresponds to a different beam direction for UE-side beam management (e.g., including beam selection and / or beam refinement). SSBs include PSS, SSS, and two-symbol PBCH. They may be transmitted at fixed timeslot locations (such as Figure 3 Symbols 0-3 shown) SSB. The UE can use PSS and SSS for cell search and acquisition. PSS can provide half-frame timing, and SS can provide CP length and frame timing. PSS and SSS can provide cell identification. PBCH carries some basic system information, such as downlink system bandwidth, timing information within a radio frame, SS burst set period, system frame number, etc. SSB can be organized into SS bursts to support beam scanning. Additional system information such as remaining minimum system information (RMSI), system information block (SIB), and other system information (OSI) can be transmitted on the physical downlink shared channel (PDSCH) in certain subframes. For example, for millimeter waves, SSB can be sent up to 64 times with up to 64 different beam directions. Multiple transmissions of SSB are called SS burst sets. SSBs in an SS burst set can be sent in the same frequency region, and SSBs in different SS burst sets can be sent in different frequency regions.

[0061] Figure 4A and Figure 4BA diagram of an example V2X system according to some aspects of the present disclosure is shown. For example, Figure 4A and Figure 4B The vehicles shown can communicate via sidelink channels and can relay sidelink transmissions as described herein. A V2X system can be an example of a sidelink communication system discussed herein, and vehicles and other devices can be configured to communicate via sidelink channels discussed herein.

[0062] Figure 4A and Figure 4B The V2X system provided in provides two complementary transmission modes. Figure 4A The first transmission mode (also referred to as Mode 4) shown by way of example in FIG. 4 involves direct communication between participants that are adjacent to each other in a local area (eg, also referred to as sidelink communication). Figure 4B The second transmission mode (also referred to as Mode 3) shown by way of example in FIG. 5 involves network communication through a network, which may be implemented through a Uu interface (eg, a wireless communication interface between a radio access network (RAN) and a UE).

[0063] refer to Figure 4A , a V2X system 400 (e.g., including vehicle-to-vehicle (V2V) communications) is shown with two vehicles 402, 404. A first transmission mode allows direct communication between different participants in a given geographic location. As shown, the vehicles can have a wireless communication link 406 with an individual (V2P) through a PC5 interface (e.g., via a UE). Communication between vehicles 402 and 404 can also occur through a PC5 interface 408. In a similar manner, communication can occur from vehicle 402 to other highway components (e.g., highway component 410) such as traffic signals or signs (V2I) through a PC5 interface 412. For Figure 4A For each communication link shown, bidirectional communication can occur between elements, so each element can be a transmitter and receiver of information. The V2X system 400 can be a self-managed system that is implemented without the assistance of a network entity. The self-managed system can improve spectrum efficiency, reduce costs, and increase reliability because no network service interruption occurs during handover operations of mobile vehicles. The V2X system can be configured to operate in a licensed spectrum or an unlicensed spectrum, so any vehicle equipped with the system can access common frequencies and share information. This coordinated / common spectrum operation allows for safe and reliable operation.

[0064] Figure 4BA V2X system 450 is shown for communicating between a vehicle 452 and a vehicle 454 via a network entity 456. These network communications may occur via discrete nodes such as a BS (e.g., BS 110a) that send information to and receive information from (e.g., relay information between) the vehicles 452, 454. Network communications via vehicle-to-network (V2N) links 458 and 460 may be used, for example, for long-range communications between vehicles, such as for communicating the presence of a car accident some distance ahead along a road or highway. The wireless nodes may send other types of communications to the vehicles, such as traffic flow conditions, road hazard warnings, environmental / weather reports, and service station availability. Such data may be obtained from a cloud-based sharing service.

[0065] Roadside units (RSUs) may be utilized. RSUs may be used for V2I communications. In some examples, RSUs may act as forwarding nodes to extend coverage to UEs. In some examples, RSUs may be co-located with BSs or may be independent. RSUs may be classified in different ways. For example, RSUs may be classified as UE-type RSUs and micro NodeB-type RSUs. Micro NodeB-type RSUs have similar functions to macro eNBs or gNBs. Micro NodeB-type RSUs may utilize the Uu interface. UE-type RSUs may be used to meet stringent quality of service (QoS) requirements by minimizing conflicts and improving reliability. UE-type RSUs may use centralized resource allocation mechanisms to allow efficient resource utilization. Critical information (e.g., such as traffic conditions, weather conditions, congestion statistics, sensor data, etc.) may be broadcast to UEs in the coverage area. Relays may rebroadcast critical information received from some UEs. UE-type RSUs may be reliable synchronization sources.

[0066] Figure 5 is a schematic diagram of an example network 500 showing multiple CV2X devices operating in an unlicensed spectrum. The unlicensed spectrum can be an example of a sidelink frequency band. Additionally, the network 500 can be an example of a sidelink communication system. The CV2X devices 502 can be configured to communicate on the sidelink frequency channels discussed herein. For example, any CV2X device 502 can communicate with any other CV2X device 502.

[0067] In the example shown, seven CV2X devices (e.g., a first CV2X device 502a, a second CV2X device 502b, a third CV2X device 502c, a fourth CV2X device 502d, a fifth CV2X device 502e, a sixth CV2X device 502f, and a seventh CV2X device 502g) - collectively referred to as CV2X devices 502 - can operate in an unlicensed spectrum with other non-CV2X devices (e.g., non-CV2X devices 504a-504c - collectively referred to as non-CV2X). In some examples, the first CV2X device 502a, the sixth CV2X device 502f, and the third CV2X device 502c can be part of a convoy or platoon. In transportation, platooning or grouping is a method for driving a group of vehicles together. It is intended to increase the capacity of roads via automated highway systems. Platooning reduces the distance between cars or trucks, such as based on SL communication.

[0068] Although the provided example shows six automobile CV2X devices in traffic and a drone or other aerial vehicle CV2X device, it is understood that the CV2X devices and environments can be extended beyond these devices and environments and include other wireless communication devices and environments. For example, the CV2X device 502 can include a UE (e.g., Figure 1 The UE 120 may be a roadside unit (RSU) operated by a highway management agency and may be implemented on a motorcycle or a device carried by a user (e.g., a pedestrian, a cyclist, etc.), or may be implemented on another aerial vehicle such as a helicopter.

[0069] The CV2X device 502 may include a UE (eg, Figure 1 UE 120), and may be a device implemented on a motorcycle or carried by a user (eg, a pedestrian, a cyclist, etc.), or implemented as a roadside unit.

[0070] In some aspects, sidelink communications (e.g., vehicle-to-everything (V2X) communications) may occur in a time division duplex (TDD) manner. That is, a UE communicating in a sidelink transmits and receives sidelink signals in the same carrier or frequency band, but the transmission time is different from the reception time. When a user equipment (UE) communicates in a TDD manner, in some aspects, the UE may be scheduled to neither transmit nor receive during a period (e.g., a gap period, which may be a gap symbol), so that the hardware of the UE (e.g., a radio front end) may switch from a transmit (Tx) mode to a receive (Rx) mode, or vice versa. In some aspects, sidelink communications may be decoupled from synchronization, meaning that they are not synchronized in time because there may be no central unit to provide synchronization. For example, a receiving UE may receive a sidelink transmission from device A (e.g., another UE), but may be synchronized with device B (e.g., another UE, a base station (BS), or a global navigation satellite system (GNSS)). For example, for a sidelink transmission from device A, decoupling may result in a propagation delay of unknown length at the receiving UE due to different synchronization sources. The gap period may accommodate such propagation delays because, since no transmission or reception is scheduled during the gap period, the receiving UE is able to receive the delayed signal during the gap period without conflicting with other communications.

[0071] In some aspects, such as in some CV2X systems, the last symbol in time of a slot may be reserved as a gap period (referred to as a gap symbol for certain UEs), meaning that there may be no signal scheduled for transmission in the gap symbol and the UE may not be scheduled to receive in the gap symbol. For example, the gap symbol may provide sufficient time for the UE to switch from Tx (or Rx) mode to Rx (or Tx) mode. In some aspects, when a slot has a configured physical sidelink feedback channel (PSFCH (for hybrid automatic repeat request (HARQ) feedback) resource, two OFDM symbols may be reserved as gaps (see reference 1 below). Fig. 6A and Figure 6B description).

[0072] In some aspects, sidelink communications may have a near-far effect. For example, if the transmitting UE is closer to the receiving UE (e.g., 100 meters), the receiving UE receives the transmission with a higher power than the transmitting UE is away from the receiving UE (e.g., 1 kilometer). Therefore, at the receiving UE, the received signal power may vary across time slots. In some aspects, the first time symbol in a time slot (or transmission) may be used to adjust the automatic gain control (AGC) training of the gain used by the UE for transmission, thereby adapting to the near-far effect. In some cases, the receiving UE may not decode the AGC symbol, so the AGC symbol does not need to carry useful information. For example, in some aspects, the AGC symbol may be a copy of the next symbol sent in the time slot.

[0073] Fig. 6A and Figure 6B 600 and 650 are example transmission timelines for sidelink communications. In transmission timeline 600, a UE (e.g., Figure 1 1 ) transmits a physical sidelink control channel (PSCCH) 602 that allocates other symbols in slot 630 for a physical sidelink shared channel (PSSCH) 604. As previously described, the UE may transmit an AGC signal in symbol 612, which may be a copy of the next OFDM symbol 610 that occurs immediately in time after symbol 662. The UE also refrains from transmitting during the last symbol 620 (the gap symbol) of the slot.

[0074] refer to Figure 6B , in transmission timeline 650, PSFCH resources are configured in symbol 664. UE (e.g., Figure 1 120a) sends PSCCH 652, which allocates other symbols in time slot 680 for PSSCH 654. As previously described, the UE can send an AGC signal in symbol 662, which can be a copy of OFDM symbol 660 that appears immediately after symbol 662 in time. Another UE (e.g., Figure 1 1) receives PSCCH 652 and PSSCH 654. The other UE sends HARQ feedback about PSSCH 654 (or alternatively or additionally, the PSSCH sent in the previous time slot in time according to the same format as time slot 680) during symbol 664. The other UE copies OFDM symbol 664 into symbol 666 for use as an AGC symbol. Both UEs refrain from transmitting during the last symbol 670 of the time slot and during symbol 672 immediately preceding AGC symbol 666.

[0075] In the above sidelink communication design, among the 14 symbols in a time slot, at least 2 symbols (e.g. Fig. 6A Symbols 612, 620 and Figure 6B Symbols 662, 666, 670, 672) in are used for AGC signals and / or gap periods.

[0076] As discussed, channel access and / or resource reservation may rely on sensing of a channel using an LBT process to identify whether the channel is idle. In some cases, if the device has not transmitted within a certain threshold time (e.g., 16 μs), the LBT process may be triggered on the device before transmitting. For example, in some cases, the duration of the gap period and / or the AGC signal may exceed a threshold, which will trigger the UE to perform LBT.

[0077] Example of a time slot format for sidelink communication

[0078] Certain aspects of the present disclosure provide techniques for configuring symbols for sidelink communication, wherein the symbols include a gap portion and a signal portion, which can be used for automatic gain control (AGC) tuning. A UE performing sidelink communication can suppress transmission during the gap portion of the symbol, send or receive an automatic gain control (AGC) signal during the signal portion of the symbol, and send or receive a data signal.

[0079] According to certain aspects of the present disclosure, for example, Fig. 7A and Figure 7B As shown, a technique is provided for using 13 of 14 symbols (leaving 1 symbol unused) in a slot without PSFCH and using 12 of 14 symbols in a slot with PSFCH.

[0080] According to certain aspects of the present disclosure, a UE may send or receive sidelink communications using a sidelink resource structure design that accommodates gaps for turnaround and / or adaptation to propagation delay and signals for AGC training in the same symbol.

[0081] In certain aspects of the present disclosure, the duration of the gap is less than a threshold (e.g., 16 μs, 25 μs, etc.), so that multiple UEs can share channel resources. For example, a UE can transmit after a gap (which is less than a gap threshold specified by regional regulations) without performing a channel access procedure (e.g., type 1 channel access based on channel sensing with random backoff; in some contexts, it can be referred to as category 4 listen before talk (LBT), similar to that defined in 3GPP Release 15 (TS 37.213), incorporated herein by reference); in other words, the UE can transmit after the gap without performing channel sensing (e.g., LBT), or the UE can perform a channel access procedure before transmitting after the gap (e.g., similar to the type 2 channel access procedure defined in 3GPP Release 15, incorporated herein by reference), thereby sharing channel resources with another UE. Various aspects of the present disclosure can achieve sidelink communication performance, such as lower latency and / or higher data rates, for example, due to the ability to transmit data signals without performing LBT or other channel sensing.

[0082] Fig. 7A and 7B 700 and 750 are example transmission timelines 700 and 750 for sidelink communications according to aspects of the present disclosure. In transmission timeline 700, a UE (e.g., Figure 1 1 ) transmits a PSCCH 702 that allocates other symbols in a time slot 730 for a PSSCH 704. The UE transmits an AGC signal 711 for AGC training during an AGC portion 712 of a symbol 713. The UE also refrains from transmitting during a gap portion 714 of the symbol 713. The gap portion 714 may be shorter than a threshold (e.g., 16 μs, 25 μs, etc.) associated with triggering an LBT procedure, such that the UE may transmit without performing LBT (e.g., Type 1 channel access (or, Category 4 LBT)).

[0083] refer to Figure 7B , in transmission timeline 750, PSFCH resources are configured in symbol 764. UE (e.g., Figure 1 1) transmits PSCCH 752, which allocates the other symbols in time slot 780 for PSSCH 754. The UE transmits AGC signal 761 during AGC portion 762 of symbol 763. Another UE (e.g., Figure 1120b) may send HARQ feedback on the PSSCH on the PSFCH during symbol 764. The other UE sends an AGC signal 766 during the AGC portion 767 of symbol 768. Both UEs suppress transmission during the gap portion 759 of symbol 763 and during the gap portion 765 of symbol 768. Each of the gap portion 759 and the gap portion 765 may be shorter than a threshold associated with triggering the LBT process. Although both transmission timelines 700 and 750 show that the gap portion and the AGC portion occur during the first symbol in time of a transmission starting in the first symbol 713 and 763 (e.g., a symbol with index=0) in time slots 730 and 780, the present disclosure is not limited thereto, and the gap portion and the AGC portion (with the AGC signal) may occur during the first symbol of a transmission that may start in any symbol of the time slot (e.g., any symbol with any index).

[0084] Figure 8 8 is a flow chart illustrating example operations 800 for wireless communications in accordance with certain aspects of the present disclosure. Operations 800 may be performed, for example, by a UE (e.g., UE 120a in wireless communication network 100). Operations 800 may be implemented as a processor (e.g., Figure 2 In addition, for example, the communication may be performed via one or more antennas (e.g., Figure 2 The antenna 252 of the UE implements the transmission and reception of signals by the UE in operation 800. In some aspects, the transmission and / or reception of signals by the UE may be implemented via a bus interface that obtains and / or outputs signals via one or more processors (e.g., the controller / processor 280).

[0085] Operation 800 may start at block 802, where the UE may suppress transmission during a gap portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion. As used herein, the first symbol in time may refer to a symbol position in a symbol sequence over time. As described above, the first symbol of the sidelink transmission of block 802 may be any symbol of the time slot, and not necessarily the first symbol of the symbol sequence in the time slot. In some aspects, the UE may identify that the gap portion has a first duration and the signal portion has a second duration, wherein the first duration and the second duration may be parts of the symbol duration. That is, the UE may determine the duration of the gap portion and / or the signal portion. In some cases, the UE may be preconfigured with the duration of the gap portion and / or the signal portion. In some cases, the UE may be configured with the duration of the gap portion and / or the signal portion by a network entity (e.g., a base station and / or an RSU) and / or another UE.

[0086] At block 804, the UE may transmit a signal during the signal portion of the first symbol. In some aspects, the signal may include an AGC signal. For example, the signal may enable another UE receiving the signal to perform an automatic gain control operation, such as adjusting a gain applied to a received signal at a receiver based on one or more properties of the signal (e.g., a received power of the signal).

[0087] Operations 800 may continue at block 806 where the UE may send a data signal for the sidelink transmission in at least one second symbol that is temporally subsequent to the first symbol in the sidelink transmission. As used herein, the second symbol that is temporally subsequent to the first symbol may refer to a symbol position of the second symbol that is subsequent to the symbol position of the first symbol in the symbol sequence.

[0088] According to various aspects of the present disclosure, the AGC signal of block 804 may include a first orthogonal frequency division multiplexing (OFDM) symbol without a cyclic prefix (CP), and the data signal of block 806 may include a second OFDM symbol with a CP. In other words, according to various aspects of the present disclosure, the first OFDM symbol is a special symbol in the sidelink communication; the first OFDM symbol consists of a signal without a CP and a gap before the signal.

[0089] In aspects of the disclosure, the AGC signal of block 804 may include a first orthogonal frequency division multiplexing (OFDM) symbol having a first cyclic prefix (CP) of a length, and the data signal of block 806 may include a second OFDM symbol having a second CP of the length.

[0090] According to aspects of the present disclosure, the AGC signal of block 804 may include a first orthogonal frequency division multiplexing (OFDM) symbol including a first number of samples, and the data signal of block 806 may include a second OFDM symbol including a second number of samples, wherein the second number is greater than the first number. In some such aspects, the UE sends a subset of samples from the AGC signal in the first OFDM symbol. In some such aspects, the UE sends a subset of samples of the second OFDM symbol in the first OFDM symbol; for example, the UE directly repeats a subset of samples from the second OFDM symbol, or sends the second OFDM symbol with additional CP samples so that the additional CP samples can be used for AGC purposes (e.g., AGC training); in other words, the second symbol has an additional CP that causes the second symbol to start within the duration of the first symbol, and the CP portion extending into the first symbol can be used by the receiver UE for AGC training. In some other such aspects, the device performing operation 800 may determine the first number so that the length of the gap portion of block 802 is less than a threshold length. In some of these aspects, the threshold length is at least one of: a fixed value or configured according to a set of candidate values ​​(eg, 16 or 25 microseconds (μs)).

[0091] In aspects of the present disclosure, the sidelink transmission of block 802 may include a sidelink feedback channel, and the data signal of block 806 may include a feedback signal.

[0092] According to aspects of the present disclosure, sending the AGC signal in block 804 may include sending a copy of a portion of the data signal of block 806. In some such aspects, the portion of the data signal (i.e., the portion sent in the AGC signal of block 804) may include a cyclic prefix (CP) of the data signal of block 806.

[0093] In aspects of the present disclosure, the sidelink transmission of block 802 may span time slots.

[0094] According to aspects of the present disclosure, the sidelink transmission of block 802 may include an instance of a physical sidelink channel (e.g., a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), or a physical sidelink feedback channel (PSFCH)).

[0095] Fig. 9 900 is a flow chart illustrating example operations 900 of wireless communication according to certain aspects of the present disclosure. Operations 900 may be performed, for example, by another UE (e.g., UE 120b in wireless communication network 100). Operations 900 may be in addition to operations 800 performed by the UE. Operations 900 may be implemented as a processor (e.g., Figure 2In addition, the communication may be performed, for example, via one or more antennas (e.g., Figure 2 The antenna 252 of the UE implements the transmission and reception of signals by the UE in operation 900. In some aspects, the transmission and / or reception of signals by the BS can be implemented via a bus interface that obtains and / or outputs signals by one or more processors (e.g., the controller / processor 280).

[0096] Operations 900 may begin at block 904, where the UE may receive a signal during a signal portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion following the gap portion. In certain aspects, the UE may identify that the gap portion has a first duration and the signal portion has a second duration, wherein the first duration and the second duration may be portions of a symbol duration.

[0097] Operations 900 may continue at block 906 where the UE may receive a data signal for the sidelink transmission in at least one second symbol that is temporally subsequent to the first symbol in the sidelink transmission.

[0098] In some aspects, the signal may include an AGC signal. The signal may enable the UE to perform an automatic gain control operation. For example, optionally, at block 908, the UE may adjust a gain applied to a received signal (e.g., another signal) based on the signal, such as a property of the signal (e.g., received signal power). That is, the UE may receive another signal and adjust the gain applied to the other received signal based on the signal received at block 904.

[0099] According to aspects of the present disclosure, the AGC signal of block 904 may include a first orthogonal frequency division multiplexing (OFDM) symbol without a cyclic prefix (CP); and the data signal of block 906 may include a second OFDM symbol with a CP.

[0100] In various aspects of the present disclosure, the AGC signal of block 904 may include a first orthogonal frequency division multiplexing (OFDM) symbol with a first cyclic prefix (CP) having a length; and the data signal of block 906 may include a second OFDM symbol with a second CP having the length.

[0101] According to aspects of the present disclosure, the AGC signal of block 904 may include a first orthogonal frequency division multiplexing (OFDM) symbol including a first number of samples; and the data signal includes a second OFDM symbol including a second number of samples, wherein the second number is greater than the first number. In some such aspects, the first OFDM symbol may include a subset of samples of the second OFDM symbol; for example, a subset of samples from the second OFDM symbol may be included in the first OFDM symbol, or the second OFDM symbol may include additional CP samples such that the additional CP samples may be used for AGC purposes (e.g., AGC training); in other words, the second symbol has an additional CP that causes the second symbol to start within the duration of the first symbol, and the CP portion extending into the first symbol may be received by the UE, for example, to be used by the UE for AGC training. In some other such aspects, the UE performing operation 900 may determine the first number such that the length of the gap portion is less than a threshold length (e.g., duration). In some aspects, the gap portion may be less than a threshold duration. In some of these other aspects, the threshold length is at least one of: a fixed value or configured according to a set of candidate values ​​(eg, 16 or 25 microseconds (μs)).

[0102] According to aspects of the present disclosure, the sidelink transmission of block 904 may include a sidelink feedback channel, and the data signal of block 906 may include a feedback signal.

[0103] In aspects of the disclosure, receiving the AGC signal in block 904 includes receiving a copy of a portion of the data signal of block 906. In some such aspects, the portion of the data signal includes a cyclic prefix (CP) of the block 906 data signal.

[0104] According to aspects of the present disclosure, the sidelink transmission of block 904 may span time slots.

[0105] According to aspects of the present disclosure, the sidelink transmission of block 904 may include an instance of a physical sidelink channel (e.g., a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), or a physical sidelink feedback channel (PSFCH)).

[0106] In various aspects of the present disclosure, the first symbol (e.g., the first symbol of a time slot) in a sidelink transmission (e.g., an OFDM symbol) can be configured to have a gap portion and an AGC portion. In the gap portion, no signal is sent. In the AGC portion, a signal is sent, but the transmitting UE can assume that the receiving UE will not decode the signal. That is, the transmitting UE can assume that the receiving UE will use the signal in the AGC portion of the symbol for AGC training purposes.

[0107] According to aspects of the present disclosure, a UE may transmit an OFDM symbol without a cyclic prefix (CP) in the first symbol of a transmission. In an example of an NR OFDM implementation, a CP may be added to a signal output from an inverse fast Fourier transform (IFFT). In these aspects, no CP is added to the first OFDM symbol, and thus this will create a gap between the signal in the first OFDM symbol and the transmission in the previous slot.

[0108] According to aspects of the present disclosure, a UE may send an OFDM symbol in the first symbol of a transmission with a CP having the same length as the CPs of other symbols in the slot. In an example of an OFDM implementation, the CP of the first symbol added to the slot may be longer than the CPs of other symbols in the slot, and the slot will have 1 / 2 μ ms duration, where μ=0, 1, 2, ... depending on the parameter set and / or subcarrier spacing of the NR OFDM implementation. In these aspects, the first symbol in a transmission (e.g., the first symbol in a slot) does not have an additional CP length of the NR OFDM implementation, which results in a gap between the transmission in the first symbol of the slot and the transmission in the previous slot.

[0109] In various aspects of the present disclosure, a UE may send an OFDM symbol in a first symbol that has fewer samples than other symbols in the time slot. For example, the UE may send only the last portion of the samples in the first OFDM symbol (these samples may be generated based on the AGC signal of the first OFDM symbol) so that there is a gap that is less than or equal to a threshold (e.g., 16 or 25 μs) at the beginning of the transmission. In other aspects, the UE may send a subset of samples of a second OFDM symbol; the subset of samples may serve as an AGC signal. As used herein, for example, for a fast Fourier transform (FFT) and / or an inverse FFT (IFFT), a symbol may be considered to have a certain number of samples in the time domain. A subset or portion of samples of a symbol may refer to a fragment or portion of a symbol in the time domain. In one example, the UE determines the number of samples that can be sent in the first symbol, copies the number of samples from the second OFDM symbol (e.g., from the last portion of the samples in the second OFDM symbol), and sends the number of samples in the first symbol. In another example, the UE may be configured to add an additional CP to the second OFDM symbol so that the CP portion of the second OFDM symbol is transmitted in the first OFDM symbol and used as an AGC signal.

[0110] According to aspects of the present disclosure, receiving the AGC signal in block 904 may include receiving a copy of a portion of the data signal of block 906. In some such aspects, the portion of the data signal (i.e., the portion sent in the AGC signal of block 804) may include a cyclic prefix (CP) of the data signal of block 906.

[0111] Figure 10A-10E are example transmission timelines 1000, 1020, 1040, 1060, and 1080 having a gap period and an AGC signal in the first symbol of a time slot according to aspects of the present disclosure. Fig. 10A , in example transmission timeline 1000, a UE (e.g., UE 120a in wireless network 100) transmits an OFDM symbol without a cyclic prefix (CP) in a first symbol 1004 of transmission 1005. The lack of a CP in the first OFDM symbol 1004 results in a gap 1006 at the beginning of the time slot. That is, the UE may refrain from transmitting during gap 1006, which may have the same duration as a CP of another symbol, such as CP 1014. The UE transmits another OFDM symbol 1012 with CP 1014 in the next symbol of transmission 1005.

[0112] refer to Fig. 10B , in the example transmission timeline 1020, the UE transmits an OFDM symbol with a CP 1026 in the first symbol 1024 of a transmission 1025, wherein the CP 1026 has the same length as the CPs of other symbols in the slot. In these aspects, the first symbol 1024 in the transmission 1025 (e.g., the first symbol in the slot) may not have an extended CP with an additional CP length (e.g., of an example NR OFDM implementation including more samples than a regular CP), which results in a gap 1028 between the transmission in the first symbol 1024 of the slot and a potential transmission (not shown) in the previous slot. That is, the UE may refrain from transmitting during the gap 1028, which may have a duration equal to the difference between the durations of the extended CP and the regular CP.

[0113] like Fig. 10CAs shown, in an example transmission timeline 1040, the UE transmits an OFDM symbol in a first symbol 1050 that has fewer samples 1042 than other symbols in the time slot (e.g., a second symbol 1052). The first symbol 1050 may have a first number of samples 1042, which may be less than a second number of samples 1056 of the second symbol 1052. In other words, the second number of samples 1056 may be more than the first number of samples. Therefore, there is a gap 1054 at the beginning of the transmission that is less than or equal to a threshold value (e.g., 16 or 25 μs). In other words, for a subset of the samples that make up the OFDM symbol (such as the first symbol 1050), the UE may refrain from transmitting during the gap 1054.

[0114] like Fig. 10D As shown, in the example transmission timeline 1060, the UE copies a portion 1072 of the second symbol 1070 and transmits the portion as an AGC signal 1074 in the first symbol 1062. The copied portion is less than the length of the symbol, so there is a gap 1064 at the beginning of the transmission that lasts less than or equal to a threshold value (e.g., 16 or 25 μs). In other words, the UE can refrain from transmitting during the gap 1064, and the duration of the gap 1064 can be equal to the difference between the duration of the symbol and the duration of the portion 1072.

[0115] refer to Fig.10E In the example transmission timeline 1080, the UE copies a portion 1092 or all of the second symbol 1090 and transmits the portion as a filler signal 1094, which may act as a CP with an extra length, used as an extended CP of the second symbol 1090 and / or an AGC signal. The filler signal 1094 may be arranged in the first symbol 1082 and the second symbol 1090, wherein the filler signal 1094 occupies a portion of each of the first symbol 1082 and the second symbol 1090. The portion copied into the first symbol 1082 is less than the length of the symbol, and therefore, there is a gap 1084 at the beginning of the transmission 1083 that lasts no longer than a threshold length (e.g., 16 or 25 μs). In other words, the UE may refrain from transmitting during the gap 1084, which may have a duration less than the threshold.

[0116] According to various aspects of the present disclosure, the disclosed techniques are applicable to the first symbol (eg, in time) of a sidelink transmission.For a sidelink transmission starting with the first symbol of a time slot, the disclosed techniques may be applicable to the first symbol of the time slot.

[0117] In aspects of the present disclosure, for sidelink feedback transmissions (eg, HARQ feedback), the disclosed techniques may be applied to the first symbol of the HARQ feedback transmission of the receiving UE.

[0118] According to aspects of the present disclosure, the disclosed technology may be applicable to both a transmitting UE and a receiving UE.

[0119] In various aspects of the present disclosure, a transmitting UE (e.g., a UE transmitting sidelink control, sidelink data, or sidelink feedback) may be configured to transmit from the first symbol of the transmission (e.g., the first symbol of the time slot) until the end of the transmission, which may be the last symbol of the time slot. The transmitting UE may be configured to transmit a first symbol having a regular CP length (i.e., the same CP length as other symbols), having no CP, or having a partial sample of the first symbol or a partial sample of the second symbol, or to transmit a second symbol having an additional CP length.

[0120] According to various aspects of the present disclosure, a receiving UE (e.g., a UE receiving sidelink control, sidelink data, or sidelink feedback) may be configured to start receiving after a gap in the first symbol of a transmission (e.g., the first symbol of a time slot). The gap has a predetermined duration, which may be an additional CP length of the first symbol relative to other symbols, a CP length of other symbols, a CP length in the first symbol of a time slot, or a (pre) configured length not greater than a threshold (e.g., 16 or 25 μs, etc.).

[0121] Fig.11 A communication device 1100 is shown, which may include devices configured to perform operations of the techniques disclosed herein (such as Figure 8 1100 includes various components (e.g., corresponding to means plus function components) of the communication device 1100. The communication device 1100 includes a processing system 1102 coupled to a transceiver 1108 (e.g., a transmitter and / or a receiver). The transceiver 1108 is configured to transmit and receive signals for the communication device 1100 via an antenna 1110, such as the various signals described herein. The processing system 1102 may be configured to perform processing functions for the communication device 1100, including processing signals received by and / or to be transmitted by the communication device 1100.

[0122] The processing system 1102 includes a processor 1104 coupled to a computer-readable medium / memory 1112 via a bus 1106. In some aspects, the computer-readable medium / memory 1112 is configured to store instructions (e.g., computer-executable code) that, when executed by the processor 1104, cause the processor 1104 to perform Figure 8, or other operations for performing various techniques discussed herein for having a gap portion and a signal portion. In some aspects, the computer-readable medium / memory 1112 stores code 1114 for suppressing transmission during a gap portion of a first symbol in time for a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion; code 1116 for sending a signal during the signal portion of the first symbol; and code 1118 for sending a data signal for the sidelink transmission in at least one second symbol that is temporally subsequent to the first symbol in the sidelink transmission. In some aspects, the processor 1104 has circuitry configured to implement the code stored in the computer-readable medium / memory 1112. The processor 1104 includes circuitry 1124 for suppressing transmission during a gap portion of a first symbol in time for a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion; circuitry 1126 for sending a signal during the signal portion of the first symbol; and circuitry 1128 for sending a data signal for the sidelink transmission in at least one second symbol that is temporally subsequent to the first symbol in the sidelink transmission.

[0123] Fig.12 A communication device 1200 is shown, which may include devices configured to perform operations of the techniques disclosed herein (such as Fig. 9 1200 and the like. The communication device 1200 includes a processing system 1202 coupled to a transceiver 1208 (e.g., a transmitter and / or a receiver). The transceiver 1208 is configured to transmit and receive signals for the communication device 1200, such as the various signals described herein, via an antenna 1210. The processing system 1202 may be configured to perform processing functions for the communication device 1200, including processing signals received by and / or to be transmitted by the communication device 1200.

[0124] The processing system 1202 includes a processor 1204 coupled to a computer-readable medium / memory 1212 via a bus 1206. In some aspects, the computer-readable medium / memory 1212 is configured to store instructions (e.g., computer-executable code) that, when executed by the processor 1204, cause the processor 1204 to perform Fig. 9, or other operations for performing various techniques discussed herein for having a gap portion and a signal portion. In some aspects, the computer-readable medium / memory 1212 stores code 1216 for receiving a signal during a signal portion of a first symbol in time for a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion following the gap portion; code 1218 for receiving a data signal for the sidelink transmission in at least one second symbol in time following the first symbol in the sidelink transmission; and / or code 1220 for adjusting a gain applied to the received signal based on the signal. In some aspects, the processor 1204 has circuitry configured to implement the code stored in the computer-readable medium / memory 1212. The processor 1204 includes circuitry 1226 for receiving a signal during a signal portion of a first symbol in time for a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion following the gap portion; circuitry 1228 for receiving a data signal for the sidelink transmission in at least one second symbol in time following the first symbol in the sidelink transmission; and / or circuitry 1230 for adjusting a gain applied to the received signal based on the signal.

[0125] Means for transmitting (or means for outputting to transmit) may include an antenna (e.g., antennas 252a-252r), a transceiver (e.g., transceivers 254a-254r), a processor (e.g., controller / processor 280), and / or circuitry for receiving (e.g., circuitry for transmitting 1126, 1128). Means for receiving (or means for obtaining) may include an antenna (e.g., antennas 252a-252r), a transceiver (e.g., transceivers 254a-254r), a processor (e.g., controller / processor 280), and / or circuitry for receiving (e.g., circuitry for receiving 1226, 1228). Means for suppressing transmitting may include a transceiver (e.g., transceivers 254a-254r), a processor (e.g., controller / processor 280), and / or circuitry for suppressing (e.g., circuitry for suppressing 1124). Means for adjusting may include a transceiver (e.g., transceivers 254a-254r), a processor (e.g., controller / processor 280), and / or circuitry for adjusting (e.g., circuitry for adjusting 1230). In some aspects, the various processors and / or various circuits may include circuitry, a central processing unit (CPU), a graphics processing unit (GPU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device (PLD), discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein.

[0126] Example aspects

[0127] In addition to the various aspects described above, specific combinations of the various aspects are also within the scope of the present disclosure, some of which are described in detail below:

[0128] Aspect 1: A method for wireless communication, comprising: suppressing transmission during a gap portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion; sending an automatic gain control (AGC) signal during the signal portion of the first symbol; and sending a data signal for the sidelink transmission in at least one second symbol that is temporally subsequent to the first symbol in the sidelink transmission.

[0129] Aspect 2: The method according to aspect 1, wherein: the AGC signal includes a first orthogonal frequency division multiplexing (OFDM) symbol without a cyclic prefix (CP); and the data signal includes a second OFDM symbol with a CP.

[0130] Aspect 3: A method according to Aspect 1, wherein: the AGC signal includes a first orthogonal frequency division multiplexing (OFDM) symbol with a first cyclic prefix (CP) having a length; and the data signal includes a second OFDM symbol with a second CP having the length.

[0131] Aspect 4: A method according to Aspect 1, wherein: the AGC signal includes a first orthogonal frequency division multiplexing (OFDM) symbol, the first OFDM symbol includes a first number of samples; and the data signal includes a second OFDM symbol, the second OFDM symbol includes a second number of samples, wherein the second number is greater than the first number.

[0132] Aspect 5: The method according to aspect 4, wherein the first OFDM symbol includes a subset of samples of the second OFDM symbol.

[0133] Aspect 6: The method according to any one of aspects 4-5, further comprising determining the first number such that a length of the gap portion is less than a threshold length.

[0134] Aspect 7: The method according to aspect 6, wherein the threshold length is at least one of: a fixed value or configured according to a set of candidate values ​​(eg, 16 or 25 μs).

[0135] Aspect 8: The method according to any one of aspects 1-7, wherein the sidelink transmission includes a sidelink feedback channel, and wherein the data signal includes a feedback signal.

[0136] Aspect 9: The method according to any one of aspects 1-8, wherein sending the AGC signal comprises sending a copy of a portion of the data signal.

[0137] Aspect 10: The method according to aspect 9, wherein the portion of the data signal includes a cyclic prefix (CP) of the data signal.

[0138] Aspect 11: A method according to any one of aspects 1-10, wherein the sidelink transmission spans time slots.

[0139] Aspect 12: A method according to any one of Aspects 1-11, wherein the sidelink transmission includes an instance of a physical sidelink channel (e.g., a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), or a physical sidelink feedback channel (PSFCH)).

[0140] Aspect 13: A method for wireless communication, comprising: receiving an automatic gain control (AGC) signal during a signal portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion after the gap portion; and receiving a data signal of the sidelink transmission in at least one second symbol in time after the first symbol in the sidelink transmission.

[0141] Aspect 14: The method according to Aspect 13, wherein: the AGC signal includes a first orthogonal frequency division multiplexing (OFDM) symbol without a cyclic prefix (CP); and the data signal includes a second OFDM symbol with a CP.

[0142] Aspect 15: A method according to Aspect 13, wherein: the AGC signal includes a first orthogonal frequency division multiplexing (OFDM) symbol with a first cyclic prefix (CP) having a length; and the data signal includes a second OFDM symbol with a second CP having the length.

[0143] Aspect 16: A method according to Aspect 13, wherein: the AGC signal includes a first orthogonal frequency division multiplexing (OFDM) symbol, the first OFDM symbol includes a first number of samples; and the data signal includes a second OFDM symbol, the second OFDM symbol includes a second number of samples, wherein the second number is greater than the first number.

[0144] Aspect 17: The method of aspect 16, wherein the first OFDM symbol comprises a subset of samples of the second OFDM symbol.

[0145] Aspect 18: The method according to any one of aspects 16-17, further comprising determining the first number such that a length of the gap portion is less than a threshold length.

[0146] Aspect 19: The method according to Aspect 18, wherein the threshold length is at least one of: a fixed value or configured according to a set of candidate values ​​(eg, 16 or 25 μs).

[0147] Aspect 20: A method according to any one of aspects 13-19, wherein the sidelink transmission includes a sidelink feedback channel, and wherein the data signal includes a feedback signal.

[0148] Aspect 21: The method according to any one of aspects 13-20, wherein receiving the AGC signal comprises receiving a copy of a portion of the data signal.

[0149] Aspect 22: The method according to aspect 21, wherein the portion of the data signal includes a cyclic prefix (CP) of the data signal.

[0150] Aspect 23: A method according to any one of aspects 13-22, wherein the sidelink transmission spans time slots.

[0151] Aspect 24: A method according to any one of Aspects 13-23, wherein the sidelink transmission includes an instance of a physical sidelink channel (e.g., a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), or a physical sidelink feedback channel (PSFCH)).

[0152] Aspect 25: An apparatus for wireless communication, comprising means for performing one or more of the methods in aspects 1-24 or 50-57.

[0153] Aspect 26: An apparatus for wireless communication, comprising: a memory; and a processor coupled to the memory, the memory and the processor being configured to perform the method of one or more aspects of aspects 1-24 or 50-57.

[0154] Aspect 27: A computer-readable medium comprising instructions which, when executed by a processing system, cause the processing system to perform the method of one or more of aspects 1-24 or 50-57.

[0155] Aspect 28: An apparatus for wireless communication, comprising: a memory; and a processor coupled to the memory, the processor and the memory being configured to: suppress transmission during a gap portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion; send a signal during the signal portion of the first symbol; and send a data signal of the sidelink transmission in at least one second symbol that is temporally subsequent to the first symbol in the sidelink transmission.

[0156] Aspect 29: The apparatus according to Aspect 28, wherein: the signal includes a first orthogonal frequency division multiplexing (OFDM) symbol without a cyclic prefix (CP); and the data signal includes a second OFDM symbol with a CP.

[0157] Aspect 30: An apparatus according to Aspect 28, wherein: the signal includes a first orthogonal frequency division multiplexing (OFDM) symbol, the first OFDM symbol including a first number of samples of the first OFDM symbol; and the data signal includes a second OFDM symbol, the second OFDM symbol including a second number of samples of the second OFDM symbol, wherein the second number is greater than the first number.

[0158] Aspect 31: The apparatus of aspect 30, wherein the first OFDM symbol comprises a subset of samples of the second OFDM symbol.

[0159] Aspect 32: An apparatus according to any one of aspects 28-31 or 33, wherein the gap portion is less than a threshold duration in time.

[0160] Aspect 33: An apparatus according to Aspect 28, wherein: the signal includes a first orthogonal frequency division multiplexing (OFDM) symbol with a first cyclic prefix (CP) having a length; and the data signal includes a second OFDM symbol with a second CP having the length.

[0161] Aspect 34: An apparatus according to any one of aspects 28-33, wherein the sidelink transmission includes a sidelink feedback channel, and wherein the data signal includes a feedback signal.

[0162] Aspect 35: The apparatus according to any one of aspects 28-34, wherein the processor and the memory are configured to send a copy of a portion of the data signal.

[0163] Aspect 36: The apparatus according to aspect 35, wherein the portion of the data signal includes a cyclic prefix (CP) of the data signal.

[0164] Aspect 37: An apparatus according to any one of Aspects 28-36, wherein the sidelink transmission spans a time slot.

[0165] Aspect 38: The apparatus according to any one of aspects 28-37, wherein the signal is an automatic gain control signal.

[0166] Aspect 39: An apparatus for wireless communication, comprising: a memory; and a processor coupled to the memory, the processor and the memory being configured to: receive a signal during a signal portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion after the gap portion, and receive a data signal of the sidelink transmission in at least one second symbol in time after the first symbol in the sidelink transmission.

[0167] Aspect 40: The apparatus according to aspect 39, wherein: the signal includes a first orthogonal frequency division multiplexing (OFDM) symbol without a cyclic prefix (CP); and the data signal includes a second OFDM symbol with a CP.

[0168] Aspect 41: An apparatus according to Aspect 39, wherein: the signal includes a first orthogonal frequency division multiplexing (OFDM) symbol, the first OFDM symbol including a first number of samples of the first OFDM symbol; and the data signal includes a second OFDM symbol, the second OFDM symbol including a second number of samples of the second OFDM symbol, wherein the second number is greater than the first number.

[0169] Aspect 42: The apparatus of aspect 41, wherein the first OFDM symbol comprises a subset of samples of the second OFDM symbol.

[0170] Aspect 43: An apparatus according to any one of aspects 39-42 or 44, wherein the gap portion is less than a threshold duration in time.

[0171] Aspect 44: An apparatus according to Aspect 39, wherein: the signal includes a first orthogonal frequency division multiplexing (OFDM) symbol with a first cyclic prefix (CP) having a length; and the data signal includes a second OFDM symbol with a second CP having the length.

[0172] Aspect 45: An apparatus according to any one of Aspects 39-44, wherein the sidelink transmission includes a sidelink feedback channel, and wherein the data signal includes a feedback signal.

[0173] Aspect 46: The apparatus according to any one of aspects 39-45, wherein the processor and the memory are configured to receive a copy of the portion of the data signal.

[0174] Aspect 47: The apparatus according to aspect 46, wherein the portion of the data signal includes a cyclic prefix (CP) of the data signal.

[0175] Aspect 48: An apparatus according to any one of Aspects 39-47, wherein the sidelink transmission spans time slots.

[0176] Aspect 49: The apparatus according to any one of aspects 39-48, wherein the processor and the memory are further configured to receive another signal and adjust the gain applied to the other signal based on the signal.

[0177] Aspect 50: A method for wireless communication, comprising: suppressing transmission during a gap portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion; sending a signal during the signal portion of the first symbol; and sending a data signal of the sidelink transmission in at least one second symbol in time after the first symbol in the sidelink transmission.

[0178] Aspect 51: A method according to Aspect 50, wherein: the signal includes a first orthogonal frequency division multiplexing (OFDM) symbol without a cyclic prefix (CP); and the data signal includes a second OFDM symbol with a CP.

[0179] Aspect 52: A method according to Aspect 50, wherein: the signal includes a first orthogonal frequency division multiplexing (OFDM) symbol, the first OFDM symbol including a first number of samples of the first OFDM symbol; and the data signal includes a second OFDM symbol, the second OFDM symbol including a second number of samples of the second OFDM symbol, wherein the second number is greater than the first number.

[0180] Aspect 53: A method according to Aspect 50, wherein: the signal includes a first orthogonal frequency division multiplexing (OFDM) symbol with a first cyclic prefix (CP) having a length; and the data signal includes a second OFDM symbol with a second CP having the length.

[0181] Aspect 54: A method for wireless communication, comprising: receiving a signal during a signal portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion after the gap portion; and receiving a data signal of the sidelink transmission in at least one second symbol after the first symbol in the sidelink transmission.

[0182] Aspect 55: A method according to aspect 54, wherein: the signal includes a first orthogonal frequency division multiplexing (OFDM) symbol without a cyclic prefix (CP); and the data signal includes a second OFDM symbol with a CP.

[0183] Aspect 56: A method according to Aspect 54, wherein: the signal includes a first orthogonal frequency division multiplexing (OFDM) symbol, the first OFDM symbol including a first number of samples of the first OFDM symbol; and the data signal includes a second OFDM symbol, the second OFDM symbol including a second number of samples of the second OFDM symbol, wherein the second number is greater than the first number.

[0184] Aspect 57: A method according to Aspect 54, wherein: the signal includes a first orthogonal frequency division multiplexing (OFDM) symbol with a first cyclic prefix (CP) having a length; and the data signal includes a second OFDM symbol with a second CP having the length.

[0185] Other considerations

[0186] The techniques described herein can be used for various wireless communication technologies, such as NR (e.g., 5G NR), 3GPP Long Term Evolution (LTE), Advanced LTE (LTE-A), Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), Time Division Synchronous Code Division Multiple Access (TD-SCDMA), and other networks. The terms "network" and "system" are often used interchangeably. A CDMA network can implement radio technologies such as Universal Terrestrial Radio Access (UTRA), cdma2000, and the like. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. cdma2000 covers IS-2000, IS-95, and IS-856 standards. A TDMA network can implement radio technologies such as Global System for Mobile Communications (GSM). OFDMA networks can implement radio technologies such as NR (e.g., 5G RA), Evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE802.11 (WiFi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDMA, etc. UTRA and E-UTRA are part of Universal Mobile Telecommunications System (UMTS). LTE and LTE-A are versions of UMTS that use EUTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, and GSM are described in documents from an organization named "3rd Generation Partnership Project" (3GPP). cdma2000 and UMB are described in documents from an organization named "3rd Generation Partnership Project 2" (3GPP 2). NR is an emerging wireless communication technology under development.

[0187] In 3GPP, the term "cell" can refer to the coverage area of ​​a NodeB (NB) and / or a NB subsystem serving the coverage area, depending on the context in which the term is used. In NR systems, the terms "cell" and BS, next-generation NodeB (gNB or gNodeB), access point (AP), distributed unit (DU), carrier or transmit receive point (TRP) can be used interchangeably. The BS can provide communication coverage for macro cells, pico cells, femto cells and / or other types of cells. A macro cell can cover a relatively large geographic area (e.g., a radius of several kilometers) and can allow unrestricted access to UEs with service subscriptions. A pico cell can cover a relatively small geographic area and can allow unrestricted access to UEs with service subscriptions. A femto cell can cover a relatively small geographic area (e.g., a home) and can allow UEs associated with the femto cell (e.g., UEs in a closed subscriber group (CSG), UEs of users in a home, etc.) to have restricted access. The BS of a macro cell can be called a macro BS. The BS of a pico cell can be called a pico BS. The BS of a femto cell can be called a femto BS or a home BS.

[0188] UE may also be referred to as a mobile station, terminal, access terminal, subscriber unit, station, customer premises equipment (CPE), cellular phone, smart phone, personal digital assistant (PDA), wireless modem, wireless communication device, handheld device, laptop computer, cordless phone, wireless local loop (WLL) station, tablet computer, camera, gaming device, netbook, smartbook, ultrabook, appliance, medical device or medical equipment, biometric sensor / device, wearable device (such as smart watch, smart clothing, smart glasses, smart wristband, smart jewelry (e.g., smart ring, smart bracelet, etc.)), entertainment device (e.g., music device, video device, satellite radio, etc.), vehicle assembly or sensor, smart meter / sensor, industrial manufacturing instrument, global positioning system device, or any other suitable device configured to communicate via wireless or wired medium. Some UEs may be considered as machine type communication (MTC) devices or evolved MTC (eMTC) devices. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, etc., which can communicate with a BS, another device (e.g., a remote device), or some other entity. For example, a wireless node can provide connectivity to a network (e.g., a wide area network such as the Internet or a cellular network) via a wired or wireless communication link. Some UEs can be considered Internet of Things (IoT) devices, which can be narrowband IoT (NB-IoT) devices.

[0189] In some examples, access to the air interface can be scheduled. A scheduling entity (e.g., BS) allocates resources for communications between some or all devices and instruments within its service area or cell. A scheduling entity may be responsible for scheduling, allocating, reconfiguring, and releasing resources for one or more subordinate entities. That is, for scheduled communications, subordinate entities utilize resources allocated by the scheduling entity. The base station is not the only entity that can serve as a scheduling entity. In some examples, a UE may act as a scheduling entity and may schedule resources for one or more subordinate entities (e.g., one or more other UEs), and other UEs may utilize the resources scheduled by the UE for wireless communications. In some examples, a UE may act as a scheduling entity in a peer-to-peer (P2P) network and / or a mesh network. In a mesh network example, in addition to communicating with a scheduling entity, UEs may also communicate directly with each other.

[0190] The methods disclosed herein include one or more steps or actions for implementing these methods. Without departing from the scope of the claims, the method steps and / or actions can be interchangeable with each other. In other words, unless a specific order of steps or actions is specified, the order and / or use of specific steps and / or actions can be modified without departing from the scope of the claims.

[0191] As used herein, a phrase referring to "at least one" of a list of items refers to any combination of those items, including single members. For example, "at least one of a, b, or c" is intended to cover a, b, c, ab, ac, bc, and abc, as well as any combination of multiples of the same element (e.g., aa, aaa, aab, aac, abb, acc, bb, bbb, bbc, cc, and ccc or any other permutation of a, b, and c.

[0192] As used herein, the term "determining" encompasses a variety of actions. For example, "determining" may include calculating, computing, processing, deriving, investigating, searching (e.g., searching in a table, database, or another data structure), exploring, etc. In addition, "determining" may include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory), etc. In addition, "determining" may include parsing, selecting, choosing, establishing, etc.

[0193] The foregoing description is provided to enable those skilled in the art to practice the various aspects described herein. Those skilled in the art will readily appreciate the various modifications to these aspects, and the general principles defined herein can be applied to other aspects. Therefore, the claims are not intended to be limited to the aspects shown herein, but to conform to the full range consistent with the language of the claims, wherein, unless otherwise stated, the elements in the singular form are not intended to represent "one and only one", but to represent "one or more". Unless otherwise stated, the term "some" refers to one or more. All structural and functional equivalents of the elements of the various aspects described in this disclosure known to or to be known by those of ordinary skill in the art are expressly incorporated herein by reference, and are intended to be included by the claims. In addition, nothing disclosed herein is intended to be directed to the public, regardless of whether such disclosure is explicitly stated in the claims. Unless the phrase "parts for..." is used to clearly describe the elements, or in the case of method claims, the phrase "steps for..." is used to describe the elements, otherwise no claim elements are to be interpreted in this way.

[0194] The various operations of the above method can be performed by any suitable components that can perform the corresponding functions. These components may include various hardware and / or software components and / or modules, including but not limited to circuits, application specific integrated circuits (ASICs) or processors. Generally, in the case of operations shown in the figure, those operations can have corresponding corresponding components plus functional components with similar numbers.

[0195] The various exemplary logical blocks, modules, and circuits described in conjunction with the present disclosure may be implemented or performed with a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device (PLD), discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but alternatively, the processor may be any commercially available processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, a plurality of microprocessors, a combination of one or more microprocessors with a DSP core, or any other such configuration.

[0196] If implemented in hardware, an example hardware configuration may include a processing system in a wireless node. The processing system may be implemented using a bus architecture. Depending on the specific application and overall design constraints of the processing system, the bus may include any number of interconnecting buses and bridges. The bus may link together various circuits including a processor, a machine-readable medium, and a bus interface. The bus interface may be used to connect a network adapter, etc., to the processing system via the bus. The network adapter may be used to implement the signal processing functions of the PHY layer. In the case of a user terminal (see Figure 1 ), a user interface (e.g., keyboard, display, mouse, joystick, etc.) may also be connected to the bus. The bus may also link various other circuits, such as timing sources, peripherals, voltage regulators, power management circuits, etc., which are well known in the art and therefore will not be described further. The processor may be implemented using one or more general and / or special purpose processors. Examples include microprocessors, microcontrollers, DSP processors, and other circuits that can execute software. Those skilled in the art will recognize how to best implement the described functionality of the processing system depending on the specific application and the overall design constraints imposed on the entire system.

[0197] If implemented in software, these functions may be stored or sent as one or more instructions or codes on a computer-readable medium. Software should be broadly interpreted as referring to instructions, data, or any combination thereof, whether referred to as software, firmware, middleware, microcode, hardware description language, or other. Computer-readable media include computer storage media and communication media, including any media that facilitates the transfer of computer programs from one place to another. The processor may be responsible for managing the bus and general processing, including executing software modules stored on a machine-readable storage medium. A computer-readable storage medium may be coupled to a processor so that the processor can read information from the storage medium and write information to the storage medium. Alternatively, the storage medium may be integrated into the processor. For example, a machine-readable medium may include a transmission line, a carrier modulated by data, and / or a computer-readable storage medium having instructions stored thereon that is separated from a wireless node, all of which may be accessed by the processor through a bus interface. Alternatively or additionally, a machine-readable medium or any portion thereof may be integrated into a processor, such as in the case of a cache and / or a general register file. For example, examples of machine-readable storage media may include RAM (random access memory), flash memory, ROM (read-only memory), PROM (programmable read-only memory), EPROM (erasable programmable read-only memory), EEPROM (electrically erasable programmable read-only memory), registers, magnetic disks, optical disks, hard disk drives, or any other suitable storage media or any combination thereof. Machine-readable media may be embodied in a computer program product.

[0198] A software module may include a single instruction or multiple instructions, and may be distributed over several different code segments, distributed in different programs, and across multiple storage media. A computer-readable medium may include multiple software modules. A software module includes instructions that, when executed by a device such as a processor, cause a processing system to perform various functions. A software module may include a sending module and a receiving module. Each software module may reside in a single storage device or be distributed in multiple storage devices. For example, when a triggering event occurs, a software module may be loaded from a hard disk into a RAM. During the execution of a software module, a processor may load some instructions into a cache to increase access speed. Then, one or more cache lines may be loaded into a general register file for execution by the processor. When the functions of a software module are mentioned below, it will be understood that such functions are implemented by the processor when executing instructions from the software module.

[0199] Furthermore, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared (IR), radio and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio and microwave are included in the definition of medium. Disk and disc, as used herein, include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Optical disks, where magnetic disks typically reproduce data magnetically, and optical disks reproduce data optically with lasers. Thus, in some aspects, computer-readable media may include non-transitory computer-readable media (e.g., tangible media). Additionally, for other aspects, computer-readable media may include transitory computer-readable media (e.g., signals). Combinations of the above should also be included within the scope of computer-readable media.

[0200] Thus, certain aspects may include a computer program product for performing the operations presented herein. For example, such a computer program product may include a computer-readable medium having instructions stored (and / or encoded) thereon, which instructions may be executed by one or more processors to perform the operations described herein, for example, for performing the operations described herein and Figure 8 and / or Fig. 9 The operations shown in the instructions.

[0201] In addition, it should be understood that the modules and / or other appropriate components for performing the methods and techniques described herein can be downloaded and / or otherwise obtained by the user terminal and / or base station, if applicable. For example, such a device can be coupled to a server to facilitate the transfer of components for performing the methods described herein. Alternatively, the various methods described herein can be provided via a storage component (e.g., RAM, ROM, a physical storage medium such as a compact disc (CD) or a floppy disk), so that the user terminal and / or base station can obtain the various methods when the storage component is coupled to or provided to the device. In addition, any other suitable technology for providing the methods and techniques described herein to the device can be utilized.

[0202] It is to be understood that the claims are not limited to the precise configuration and components described above. Various modifications, changes and variations may be made in the arrangement, operation and details of the methods and apparatus described above without departing from the scope of the claims.

Claims

1. A device for wireless communication, comprising: Memory; and One or more processors, coupled to the memory, the one or more processors configured to: refraining from transmitting during a gap portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion, transmitting a signal during a signal portion of a first symbol, wherein the signal is an automatic gain control signal, and The data signal of the sidelink transmission is sent in at least one second symbol temporally following the first symbol in the sidelink transmission.

2. The device according to claim 1, wherein: The signal includes a first orthogonal frequency division multiplexing (OFDM) symbol without a cyclic prefix (CP); and The data signal includes a second OFDM symbol having a CP.

3. The device according to claim 1, wherein: The signal includes a first orthogonal frequency division multiplexing (OFDM) symbol, the first OFDM symbol including a first number of samples of the first OFDM symbol; and The data signal includes a second OFDM symbol including a second number of samples of the second OFDM symbol, wherein the second number is greater than the first number.

4. The device according to claim 3, wherein: The first OFDM symbol includes a subset of the samples of the second OFDM symbol.

5. The device according to claim 1, wherein: The gap portion is less than a threshold duration in time.

6. The device according to claim 1, wherein: The signal includes a first orthogonal frequency division multiplexing (OFDM) symbol with a first cyclic prefix (CP) having a length; and The data signal includes a second OFDM symbol with a second CP having the length.

7. The device according to claim 1, wherein: The sidelink transmission comprises a sidelink feedback channel, and wherein the data signal comprises a feedback signal.

8. The device according to claim 1, wherein: The processor and the memory are configured to send a copy of a portion of the data signal.

9. The device according to claim 8, wherein: The portion of the data signal includes a cyclic prefix (CP) of the data signal.

10. The device according to claim 1, wherein: The sidelink transmission spans time slots.

11. An apparatus for wireless communication, comprising: Memory; and One or more processors, coupled to the memory, the one or more processors configured to: receiving a signal during a signal portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion after the gap portion, wherein the signal is an automatic gain control signal, receiving a data signal of the sidelink transmission in at least one second symbol temporally subsequent to the first symbol in the sidelink transmission, and Another signal is received and a gain applied to the other signal is adjusted based on the automatic gain control signal.

12. The device according to claim 11, wherein: The signal includes a first orthogonal frequency division multiplexing (OFDM) symbol without a cyclic prefix (CP); and The data signal includes a second OFDM symbol having a CP.

13. The device according to claim 11, wherein: The signal includes a first orthogonal frequency division multiplexing (OFDM) symbol, the first OFDM symbol including a first number of samples of the first OFDM symbol; and The data signal includes a second OFDM symbol including a second number of samples of the second OFDM symbol, wherein the second number is greater than the first number.

14. The device according to claim 13, wherein: The first OFDM symbol includes a subset of the samples of the second OFDM symbol.

15. The device according to claim 11, wherein The gap portion is less than a threshold duration in time.

16. The device according to claim 11, wherein: The signal includes a first orthogonal frequency division multiplexing (OFDM) symbol with a first cyclic prefix (CP) having a length; and The data signal includes a second OFDM symbol with a second CP having the length.

17. The device according to claim 11, wherein: The sidelink transmission comprises a sidelink feedback channel, and wherein the data signal comprises a feedback signal.

18. The device according to claim 11, wherein The processor and the memory are configured to receive a copy of a portion of the data signal.

19. The device according to claim 18, wherein: The portion of the data signal includes a cyclic prefix (CP) of the data signal.

20. The device according to claim 11, wherein The sidelink transmission spans time slots.

21. A method for wireless communication, comprising: refraining from transmitting during a gap portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion; transmitting a signal during a signal portion of a first symbol, wherein the signal is an automatic gain control signal; and The data signal of the sidelink transmission is sent in at least one second symbol temporally following the first symbol in the sidelink transmission.

22. The method of claim 21, wherein: The signal includes a first orthogonal frequency division multiplexing (OFDM) symbol without a cyclic prefix (CP); and The data signal includes a second OFDM symbol having a CP.

23. The method of claim 21, wherein: The signal includes a first orthogonal frequency division multiplexing (OFDM) symbol, the first OFDM symbol including a first number of samples of the first OFDM symbol; and The data signal includes a second OFDM symbol including a second number of samples of the second OFDM symbol, wherein the second number is greater than the first number.

24. The method of claim 21, wherein: The signal includes a first orthogonal frequency division multiplexing (OFDM) symbol with a first cyclic prefix (CP) having a length; and The data signal includes a second OFDM symbol with a second CP having the length.

25. A method for wireless communication, comprising: receiving a signal during a signal portion of a first symbol in time of a sidelink transmission, wherein the first symbol includes a gap portion and a signal portion after the gap portion, wherein the signal is an automatic gain control signal; receiving a data signal of the sidelink transmission in at least one second symbol following the first symbol in the sidelink transmission; and Another signal is received and a gain applied to the other signal is adjusted based on the automatic gain control signal.

26. The method of claim 25, wherein: The signal includes a first orthogonal frequency division multiplexing (OFDM) symbol without a cyclic prefix (CP); and The data signal includes a second OFDM symbol having a CP.

27. The method of claim 25, wherein: The signal includes a first orthogonal frequency division multiplexing (OFDM) symbol, the first OFDM symbol including a first number of samples of the first OFDM symbol; and The data signal includes a second OFDM symbol including a second number of samples of the second OFDM symbol, wherein the second number is greater than the first number.

28. The method of claim 25, wherein: The signal includes a first orthogonal frequency division multiplexing (OFDM) symbol with a first cyclic prefix (CP) having a length; and The data signal includes a second OFDM symbol with a second CP having the length.

29. An apparatus for wireless communication, comprising: means for refraining from transmitting during a gap portion of a first symbol in time of a sidelink transmission, wherein the first symbol comprises a gap portion and a signal portion, means for transmitting a signal during a signal portion of a first symbol, wherein the signal is an automatic gain control signal, and Means for sending a data signal for a sidelink transmission in at least one second symbol that temporally follows a first symbol in the sidelink transmission.

30. An apparatus for wireless communication, comprising: means for receiving a signal during a signal portion of a first symbol in time of a sidelink transmission, wherein the first symbol comprises a gap portion and a signal portion following the gap portion, wherein the signal is an automatic gain control signal, means for receiving a data signal of the sidelink transmission in at least one second symbol temporally subsequent to the first symbol in the sidelink transmission, and Means for receiving another signal and adjusting a gain applied to the another signal based on the automatic gain control signal.

31. A non-transitory computer-readable storage medium having stored thereon instructions for wireless communication, the instructions being executable by a processor to: Refraining from transmitting during a gap portion of a temporally first symbol of a sidelink transmission, wherein The first symbol includes a gap portion and a signal portion, transmitting a signal during a signal portion of a first symbol, wherein the signal is an automatic gain control signal, and The data signal of the sidelink transmission is sent in at least one second symbol temporally following the first symbol in the sidelink transmission.

32. A non-transitory computer-readable storage medium having stored thereon instructions for wireless communication, the instructions being executable by a processor to: receiving a signal during a signal portion of a temporally first symbol of a sidelink transmission, wherein, The first symbol includes a gap portion and a signal portion after the gap portion, wherein the signal is an automatic gain control signal, receiving a data signal of the sidelink transmission in at least one second symbol temporally subsequent to the first symbol in the sidelink transmission, and Another signal is received and a gain applied to the other signal is adjusted based on the automatic gain control signal.

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