Method, user equipment and storage medium for transmission side link transmission

Abstract

The present disclosure relates to methods, user equipment, and storage media for transmitting sidelink transmissions. Embodiments of user equipment (UE) and methods for communication are generally described herein. The UE may select a short transmission time interval (TTI) for a vehicle-to-vehicle (V2V) sidelink transmission of the UE from a plurality of short transmission time intervals (TTIs). The short TTI may occur within a traditional TTI. The short TTI may be allocated for V2V sidelink transmissions of non-traditional UEs. Traditional TTIs may be allocated for V2V sidelink transmissions of traditional UEs. The UE may send a traditional physical sidelink control channel (PSCCH) according to the traditional TTI to indicate the V2V sidelink transmission of the UE to the traditional UE. The UE may send a short PSCCH (sPSCCH) according to the selected short TTI to indicate the V2V sidelink transmission of the UE to the non-traditional UE.

Description

[0001] This application is a divisional application of a Chinese patent application with an application date of March 21, 2018, application number 201880018785.1, and invention name “User Equipment (UE) and Method for Vehicle-to-Vehicle (V2V) Side Link Communication Based on Short Transmission Time Interval (TTI)”.

[0002] Priority claim

[0003] This application claims priority to U.S. Provisional Patent Application Serial No. 62,475,690, filed on March 23, 2017, and U.S. Provisional Patent Application Serial No. 62,476,147, filed on March 24, 2017, both of which are incorporated herein by reference in their entirety. Technical Field

[0004] Embodiments relate to wireless communications. Some embodiments relate to wireless networks, including 3GPP (3rd Generation Partnership Project) networks, 3GPP LTE (Long Term Evolution) networks, and 3GPP LTE-A (LTE Advanced) networks. Some embodiments relate to fifth generation (5G) networks. Some embodiments relate to new air interface (NR) networks. Some embodiments relate to sidelink communications. Some embodiments relate to vehicle-to-vehicle (V2V) communications. Some embodiments relate to signal transmission according to different transmission time intervals (TTIs), including but not limited to short TTIs and traditional TTIs. Background Art

[0005] Mobile devices can exchange data based on sidelink communications. In some cases, such as when the mobile device is out of network coverage, the mobile device can autonomously perform sidelink communications with limited or no assistance from the base station. Various use cases for sidelink communications are possible. In example scenarios, sidelink communications based on low latency can be used, which can be challenging. There is a general need for methods and systems for enabling sidelink communications in these and other scenarios. Summary of the invention

[0006] According to one aspect of the present disclosure, there is provided a method for transmitting a sidelink transmission, comprising: a user equipment UE, selecting a sidelink resource for the sidelink transmission; and transmitting the sidelink transmission on the selected sidelink resource, wherein the sidelink transmission comprises an initial orthogonal frequency division multiplexing (OFDM) symbol, wherein the initial OFDM symbol is a copy of a second OFDM symbol, and wherein the second OFDM symbol is immediately subsequent to the initial OFDM symbol.

[0007] According to one aspect of the present disclosure, it relates to a user equipment UE, comprising: a memory; and a processing circuit, communicating with the memory and configured to: select a sidelink resource for a sidelink transmission; and transmit the sidelink transmission on the selected sidelink resource, wherein the sidelink transmission comprises an initial orthogonal frequency division multiplexing (OFDM) symbol, wherein the initial OFDM symbol is a copy of a second OFDM symbol, wherein the second OFDM symbol is immediately after the initial OFDM symbol, and wherein the second OFDM symbol comprises at least one of a physical sidelink shared data channel or a physical sidelink control channel.

[0008] According to one aspect of the present disclosure, there is provided a non-transitory computer-readable storage medium storing instructions for being executed by one or more processors to perform operations for communicating by a user equipment UE, wherein the operations are used to configure the one or more processors to: select sidelink resources for sidelink transmission; and transmit the sidelink transmission on the selected sidelink resources, wherein the sidelink transmission comprises an initial orthogonal frequency division multiplexing (OFDM) symbol, wherein the initial OFDM symbol is a copy of a second OFDM symbol, wherein the second OFDM symbol is immediately subsequent to the initial OFDM symbol, and wherein the second OFDM symbol comprises at least one of a physical sidelink shared data channel or a physical sidelink control channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1A is a functional diagram of an example network according to some embodiments;

[0010] Figure 1B is a functional diagram of another example network according to some embodiments;

[0011] Figure 2 shows a block diagram of an example machine according to some embodiments;

[0012] Figure 3 A user device according to some aspects is shown;

[0013] Figure 4 A base station according to some aspects is shown;

[0014] Figure 5 An exemplary communication circuit according to some aspects is shown;

[0015] Figure 6 shows an example of a radio frame structure according to some embodiments;

[0016] Fig. 7A and Figure 7B shows example frequency resources according to some embodiments;

[0017] Figure 8 The operation of a communication method according to some embodiments is shown;

[0018] Fig. 9 shows an example multiplexing arrangement that may be used in accordance with some embodiments;

[0019] Fig.10 shows an example multiplexing arrangement that may be used in accordance with some embodiments;

[0020] Fig.11 shows an example multiplexing arrangement that may be used in accordance with some embodiments;

[0021] Fig.12 shows example arrangements that may be used according to various transmission time intervals (TTIs) in accordance with some embodiments;

[0022] Fig.13 shows an example arrangement that may be used according to various TTIs according to some embodiments;

[0023] Fig.14 shows an example arrangement that may be used according to various TTIs according to some embodiments;

[0024] Fig.15 shows an example arrangement that may be used according to various TTIs according to some embodiments;

[0025] Fig.16 shows an example arrangement that may be used according to various TTIs according to some embodiments;

[0026] Fig.17 shows an example arrangement that may be used according to various TTIs according to some embodiments;

[0027] Fig.18A - B shows an example resource allocation that may be used according to some embodiments;

[0028] Fig.19 shows an example resource allocation that may be used in accordance with some embodiments;

[0029] Fig. 20 illustrates example techniques for resource selection according to some embodiments;

[0030] Fig.21 illustrates example techniques for resource selection according to some embodiments;

[0031] Fig. 22 illustrates example techniques for resource selection according to some embodiments; and

[0032] Fig.23Example techniques for resource selection according to some embodiments are shown. DETAILED DESCRIPTION

[0033] The following description and the accompanying drawings sufficiently illustrate the specific embodiments to enable those skilled in the art to practice them. Other embodiments may include structural, logical, electrical, process and other changes. Portions and features of some embodiments may be included in other embodiments, or replace portions and features of other embodiments. The embodiments set forth in the claims include all available equivalents of those claims.

[0034] Figure 1A is a functional diagram of an example network according to some embodiments. Figure 1B is a functional diagram of another example network according to some embodiments. In the references herein, "FIG. 1" may include Figure 1A and Figure 1B . In some embodiments, network 100 may be a third generation partnership project (3GPP) network. In some embodiments, network 150 may be a 3GPP network. In a non-limiting example, network 150 may be a new radio (NR) network. However, it should be noted that the embodiments are not limited to the use of 3GPP networks, as other networks may be used in some embodiments. As an example, in some cases a fifth generation (5G) network may be used. As another example, in some cases a new radio (NR) network may be used. As another example, in some cases a wireless local area network (WLAN) may be used. However, the embodiments are not limited to these example networks, as other networks may be used in some embodiments. In some embodiments, the network may include Figure 1A Some embodiments may not necessarily include one or more components shown in FIG. Figure 1A All components shown in FIG. 1 and some embodiments may include Figure 1A In some embodiments, the network may include Figure 1B Some embodiments may not necessarily include one or more components shown in FIG. Figure 1B All components shown in FIG. 1 and some embodiments may include Figure 1B In some embodiments, the network may include Figure 1A One or more components shown in and Figure 1B In some embodiments, the network may include one or more components shown in Figure 1A One or more of the components shown in Figure 1B One or more components shown in and one or more additional components.

[0035] The network 100 may include a radio access network (RAN) 101 and a core network 120 (e.g., shown as an evolved packet core (EPC)) coupled together via an S1 interface 115. For convenience and brevity, only a portion of the core network 120 and the RAN 101 are shown. In a non-limiting example, the RAN 101 may be an evolved universal terrestrial radio access network (E-UTRAN). In another non-limiting example, the RAN 101 may include one or more components of a new radio (NR) network. In another non-limiting example, the RAN 101 may include one or more components of an E-UTRAN and one or more components of another network (including but not limited to an NR network).

[0036] The core network 120 may include a mobility management entity (MME) 122, a serving gateway (serving GW) 124, and a packet data network gateway (PDN GW) 126. In some embodiments, the network 100 may include (and / or support) one or more evolved Node Bs (eNBs) 104 (which may operate as base stations) for communicating with user equipment (UE) 102. In some embodiments, the eNBs 104 may include macro eNBs and low power (LP) eNBs.

[0037] In some embodiments, the network 100 may include (and / or support) one or more generation Node Bs (gNBs) 105. In some embodiments, one or more eNBs 104 may be configured to operate as gNBs 105. Figure 1A The number of eNBs 104 shown in Figure 1A In some embodiments, network 100 may not necessarily include eNB 104. Embodiments are also not limited to Figure 1A Connectivity of the components shown in .

[0038] It should be noted that references herein to eNB 104 or gNB 105 are not limiting. In some embodiments, one or more operations, methods, and / or techniques (such as those described herein) may be practiced by a base station component (and / or other components), including, but not limited to, gNB 105, eNB 104, serving cell, transmit receive point (TRP), and / or others. In some embodiments, the base station component may be configured to operate in accordance with a new air interface (NR) protocol and / or NR standard, but the scope of the embodiments is not limited in this respect. In some embodiments, the base station component may be configured to operate in accordance with a fifth generation (5G) protocol and / or 5G standard, but the scope of the embodiments is not limited in this respect.

[0039] In some embodiments, one or more of the UE 102 and / or the eNB 104 may be configured to operate in accordance with the NR protocol and / or NR technology. References to the UE 102, eNB 104, and / or gNB 105 as part of the description herein are not limiting. For example, descriptions of one or more operations, techniques, and / or methods practiced by the gNB 105 are not limiting. In some embodiments, the eNB 104 and / or other base station components may practice one or more of those operations, techniques, and / or methods.

[0040] In some embodiments, UE 102 may send signals (data, control, and / or other) to gNB 105 and may receive signals (data, control, and / or other) from gNB 105. In some embodiments, UE 102 may send signals (data, control, and / or other) to eNB 104 and may receive signals (data, control, and / or other) from eNB 104. These embodiments are described in more detail below.

[0041] The MME 122 is similar in function to the control plane of a traditional service GPRS support node (SGSN). The MME 122 manages mobility aspects in access such as gateway selection and tracking area list management. The service GW 124 terminates the interface toward the RAN 101 and routes data packets between the RAN 101 and the core network 120. In addition, it can be a local mobility anchor point for inter-eNB handover and can also provide an anchor for inter-3GPP mobility. Other responsibilities may include legal interception, charging, and some policy enforcement. The service GW 124 and the MME 122 can be implemented in one physical node or in separate physical nodes. The PDN GW 126 terminates the SGi interface toward the packet data network (PDN). The PDN GW 126 routes data packets between the EPC 120 and the external PDN and can be a key node for policy enforcement and charging data collection. It can also provide an anchor point for mobility for non-LTE access. The external PDN can be any type of IP network, as well as an IP multimedia subsystem (IMS) domain. The PDN GW 126 and the Serving GW 124 may be implemented in one physical node or in separate physical nodes.

[0042] In some embodiments, the eNB 104 (macro and micro) terminates the air interface protocol and can be the first point of contact for the UE 102. In some embodiments, the eNB 104 can implement various logical functions of the network 100, including but not limited to RNC (radio network controller functions), such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management.

[0043] In some embodiments, UE 102 may be configured to communicate orthogonal frequency division multiplexing (OFDM) communication signals with eNB 104 and / or gNB 105 over a multi-carrier communication channel in accordance with an orthogonal frequency division multiple access (OFDMA) communication technique. In some embodiments, eNB 104 and / or gNB 105 may be configured to communicate OFDM communication signals with UE 102 over a multi-carrier communication channel in accordance with an OFDMA communication technique. OFDM signals may include multiple orthogonal subcarriers.

[0044] The S1 interface 115 is an interface that separates the RAN 101 and the EPC 120. It can be divided into two parts: S1-U, which carries service data between the eNB 104 and the serving GW 124; and S1-MME, which is a signaling interface between the eNB 104 and the MME 122. The X2 interface is an interface between the eNBs 104. The X2 interface includes two parts, X2-C and X2-U. X2-C is a control plane interface between the eNBs 104, and X2-U is a user plane interface between the eNBs 104.

[0045] In some embodiments, similar functionality and / or connectivity described for eNB 104 may be used for gNB 105, but the scope of the embodiments is not limited in this respect. In a non-limiting example, S1 interface 115 (and / or similar interfaces) may be divided into two parts: S1-U, which carries traffic data between gNB 105 and serving GW 124; and S1-MME, which is a signaling interface between gNB 104 and MME 122. X2 interface (and / or similar interface) may enable communication between eNBs 104, communication between gNBs 105, and / or communication between eNB 104 and gNB 105.

[0046] For cellular networks, LP cells are typically used to extend coverage to indoor areas where outdoor signals do not reach well, or to increase network capacity in areas with very dense phone use, such as train stations. As used herein, the term low power (LP) eNB refers to any suitable relatively low power eNB for implementing narrower cells (narrower than macro cells) such as femtocells, picocells, or microcells. Femtocell eNBs are typically provided by mobile network operators to their residential or enterprise customers. Femtocells are typically the size of a residential gateway or smaller and are typically connected to a user's broadband line. After insertion, the femtocell connects to the mobile operator's mobile network and provides additional coverage for residential femtocells, typically within a range of 30 to 50 meters. Therefore, an LP eNB may be a femtocell eNB because it is coupled through the PDN GW 126. Similarly, a picocell is a wireless communication system that typically covers a small area, such as indoors (offices, shopping malls, train stations, etc.) or more recently on an airplane. A picocell eNB can typically be connected to another eNB, such as a macro eNB, through its base station controller (BSC) function via an X2 link. Thus, the LP eNB may be implemented with a pico cell eNB because it is coupled to the macro eNB via an X2 interface. The pico cell eNB or other LP eNB may incorporate some or all of the functionality of the macro eNB. In some cases, this may be referred to as an access point base station or an enterprise femto cell. In some embodiments, various types of gNBs 105 may be used, including but not limited to one or more of the above eNB types.

[0047] In some embodiments, network 150 may include one or more components configured to operate in accordance with one or more 3GPP standards, including but not limited to NR standards. Figure 1B The network 150 shown in FIG. 1 may include a next generation RAN (NG-RAN) 155, which may include one or more gNBs 105. In some embodiments, the network 150 may include an E-UTRAN 160, which may include one or more eNBs. The E-UTRAN 160 may be similar to the RAN 101 described herein, but the scope of the embodiments is not limited in this respect.

[0048] In some embodiments, network 150 may include MME 165. MME 165 may be similar to MME 122 described herein, but the scope of the embodiments is not limited in this respect. MME 165 may perform one or more operations or functions similar to the operations or functions described herein with respect to MME 122, but the scope of the embodiments is not limited in this respect.

[0049] In some embodiments, network 150 may include SGW 170. SGW 170 may be similar to SGW 124 described herein, but the scope of the embodiments is not limited in this respect. SGW 170 may perform one or more operations or functions similar to the operations or functions described herein with respect to SGW 124, but the scope of the embodiments is not limited in this respect.

[0050] In some embodiments, the network 150 may include components and / or modules for functions of a user plane function (UPF) and a user plane function (PGW-U) for a PGW as shown by 175. In some embodiments, the network 150 may include components and / or modules for functions of a session management function (SMF) and a control plane function (PGW-C) for a PGW as shown by 180. In some embodiments, the components and / or modules indicated by 175 and / or 180 may be similar to the PGW 126 described herein, but the scope of the embodiments is not limited in this respect. The components and / or modules indicated by 175 and / or 180 may perform one or more operations or functions similar to those described herein with respect to the PGW 126, but the scope of the embodiments is not limited in this respect. One or both of the components 170, 172 may perform at least a portion of the functions described herein for the PGW 126, but the scope of the embodiments is not limited in this respect.

[0051] The embodiments are not limited to Figure 1B The number or type of components shown in the embodiment is not limited to Figure 1B Connectivity of the components shown in .

[0052] In some embodiments, a downlink resource grid may be used for downlink transmissions from eNB 104 to UE 102, while uplink transmissions from UE 102 to eNB 104 may use similar techniques. In some embodiments, a downlink resource grid may be used for downlink transmissions from gNB 105 to UE 102, while uplink transmissions from UE 102 to gNB 105 may use similar techniques. The grid may be a time-frequency grid, referred to as a resource grid or a time-frequency resource grid, which is a physical resource in the downlink in each time slot. This time-frequency plane representation is a common practice in OFDM systems, which makes it intuitive for radio resource allocation. Each column and row of the resource grid corresponds to an OFDM symbol and an OFDM subcarrier, respectively. The duration of the resource grid in the time domain corresponds to one time slot in a radio frame. The smallest time-frequency unit in the resource grid is represented as a resource element (RE). There are several different physical downlink channels that are transmitted using such resource blocks. Of particular relevance to the present disclosure, two of these physical downlink channels are a physical downlink shared channel and a physical downlink control channel.

[0053] As used herein, the term "circuit" may refer to, be part of, or include: an application specific integrated circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group) and / or a memory (shared, dedicated, or group) that executes one or more software or firmware programs, combinational logic circuits, and / or other suitable hardware components that provide the described functionality. In some embodiments, the circuit may be implemented in one or more software or firmware modules, or the functionality associated with the circuit may be implemented by one or more software or firmware modules. In some embodiments, the circuit may include logic that is at least partially operable in hardware. The embodiments described herein may be implemented into a system using any appropriately configured hardware and / or software.

[0054] Figure 2 A block diagram of an example machine according to some embodiments is shown. Machine 200 is an example machine on which any one or more of the techniques and / or methods discussed herein can be performed. In alternative embodiments, machine 200 can operate as a standalone device or can be connected (e.g., networked) to other machines. In a networked deployment, machine 200 can operate in the capacity of a server machine, a client machine, or both in a server-client network environment. In an example, machine 200 can act as a peer machine in a peer-to-peer (P2P) (or other distributed) network environment. Machine 200 can be UE 102, eNB 104, gNB 105, access point (AP), station (STA), user, device, mobile device, base station, personal computer (PC), tablet PC, set-top box (STB), personal digital assistant (PDA), mobile phone, smart phone, network device, network router, switch or bridge, or any machine capable of executing instructions (sequentially or otherwise) specifying the actions to be taken by the machine. Further, while a single machine is illustrated, the term "machine" shall also be taken to include any collection of machines that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies discussed herein (such as cloud computing, Software as a Service (SaaS), other computer cluster configurations, etc.).

[0055] Examples as described herein may include or may operate on a logic or multiple components, modules or mechanisms. A module is a tangible entity (e.g., hardware) that can perform a specified operation and may be configured or arranged in some way. In an example, a circuit may be arranged (e.g., internally or relative to an external entity such as other circuits) as a module in a specified manner. In an example, all or part of one or more computer systems (e.g., independent client or server computer systems) or one or more hardware processors may be configured by firmware or software (e.g., instructions, application parts or applications) as a module that performs a specified operation. In an example, the software may reside on a machine-readable medium. In an example, when executed by the underlying hardware of the module, the software causes the hardware to perform the specified operation.

[0056] Thus, the term "module" is understood to encompass a tangible entity that is physically constructed, specifically configured (e.g., hardwired) or temporarily (e.g., temporarily) configured (e.g., programmed) to operate in a specified manner or to perform part or all of any of the operations described herein. Considering the example of temporarily configured modules, each module need not be instantiated at any one time. For example, where the modules include a general-purpose hardware processor configured using software, the general-purpose hardware processor can be configured into corresponding different modules at different times. Thus, software can configure a hardware processor, for example, to constitute a particular module at one time and to constitute a different module at a different time.

[0057] The machine (e.g., computer system) 200 may include a hardware processor 202 (e.g., a central processing unit (CPU), a graphics processing unit (GPU), a hardware processor core, or any combination thereof), a main memory 204, and a static memory 206, some or all of which may communicate with each other via an interconnection link (e.g., a bus) 208. The machine 200 may further include a display unit 210, an alphanumeric input device 212 (e.g., a keyboard), and a user interface (UI) navigation device 214 (e.g., a mouse). In an example, the display unit 210, the input device 212, and the UI navigation device 214 may be a touch screen display. The machine 200 may additionally include a storage device (e.g., a drive unit) 216, a signal generating device 218 (e.g., a speaker), a network interface device 220, and one or more sensors 221, such as a global positioning system (GPS) sensor, a compass, an accelerometer, or other sensors. The machine 200 may include an output controller 228, such as a serial (e.g., universal serial bus (USB), parallel or other wired or wireless (e.g., infrared (IR), near field communication (NFC), etc.) connection to communicate with or control one or more peripheral devices (e.g., printer, card reader, etc.).

[0058] The storage device 216 may include a machine-readable medium 222 on which is stored one or more sets of data structures or instructions 224 (e.g., software) that embody or are used by any one or more of the techniques or functions described herein. The instructions 224 may also reside, in whole or in part, within the main memory 204, within the static memory 206, or within the hardware processor 202 during execution by the machine 200. In an example, one or any combination of the hardware processor 202, the main memory 204, the static memory 206, or the storage device 216 may constitute a machine-readable medium. In some embodiments, the machine-readable medium may be or may include a non-transitory computer-readable storage medium. In some embodiments, the machine-readable medium may be or may include a computer-readable storage medium.

[0059] Although the machine-readable medium 222 is shown as a single medium, the term "machine-readable medium" may include a single medium or multiple media (e.g., a centralized or distributed database, and / or associated caches and servers) configured to store one or more instructions 224. The term "machine-readable medium" may include any medium capable of storing, encoding, or carrying instructions for execution by the machine 200 and causing the machine 200 to perform any one or more of the techniques of the present disclosure, or capable of storing, encoding, or carrying data structures used by or associated with these instructions. Non-limiting machine-readable medium examples may include solid-state memory, and optical and magnetic media. Specific examples of machine-readable media may include: non-volatile memory, such as semiconductor memory devices (e.g., electrically programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM)) and flash memory devices; disks, such as internal hard disks and removable disks; magneto-optical disks; random access memory (RAM); and CD-ROM and DVD-ROM disks. In some examples, the machine-readable medium may include non-transitory machine-readable media. In some examples, the machine-readable medium may include machine-readable media that is not a transient propagation signal.

[0060] The instructions 224 may further be sent or received via the network interface device 220 using a transmission medium over a communication network 226 using any of a variety of transmission protocols (e.g., frame relay, Internet Protocol (IP), transmission control protocol (TCP), user datagram protocol (UDP), hypertext transfer protocol (HTTP), etc.). Example communication networks may include a local area network (LAN), a wide area network (WAN), a packet data network (e.g., the Internet), a mobile telephone network (e.g., a cellular network), a plain old telephone (POTS) network, and a wireless data network (e.g., a wireless network called The Institute of Electrical and Electronics Engineers (IEEE) 802.11 family of standards, known as The IEEE 802.16 family of standards, the IEEE 802.15.4 family of standards, the Long Term Evolution (LTE) family of standards, the Universal Mobile Telecommunications System (UMTS) family of standards, peer-to-peer (P2P) networks, and the like. In an example, the network interface device 220 may include one or more physical jacks (e.g., Ethernet, coaxial, or telephone jacks) or one or more antennas to connect to the communication network 226. In an example, the network interface device 220 may include multiple antennas to communicate wirelessly using at least one of single-input multiple-output (SIMO), multiple-input multiple-output (MIMO), or multiple-input single-output (MISO) technology. In some examples, the network interface device 220 may use multi-user MIMO technology for wireless communication. The term "transmission medium" should be taken to include any intangible medium capable of storing, encoding, or carrying instructions executed by the machine 200, and includes digital or analog communication signals or other intangible media to facilitate the communication of such software.

[0061] Figure 3 A user device according to some aspects is shown. In some embodiments, the user device 300 may be a mobile device. In some embodiments, the user device 300 may be or may be configured to operate as a user equipment (UE). In some embodiments, the user equipment 300 may be arranged to operate according to a new radio (NR) protocol. In some embodiments, the user equipment 300 may be arranged to operate according to a third generation partnership protocol (3GPP) protocol. In some embodiments, the user equipment 300 may be suitable for use as a UE 102 as shown in FIG. 1. It should be noted that in some embodiments, the UE, the device of the UE, the user equipment, or the device of the user equipment may include Figure 2 , Figure 3 and Figure 5 In some embodiments, such UE, user equipment and / or device may include one or more additional components.

[0062] In some aspects, user device 300 may include an application processor 305, a baseband processor 310 (also referred to as a baseband module), a wireless front end module (KFEM) 315, a memory 320, a connection module 325, a near field communication (NFC) controller 330, an audio driver 335, a camera driver 340, a touch screen 345, a display driver 350, a sensor 355, a removable memory 360, a power management integrated circuit (PMIC) 365, and a smart battery 370. In some aspects, user device 300 may be a user equipment (UE).

[0063] In some aspects, the application processor 305 may include, for example, one or more CPU cores and one or more cache memories, a low dropout regulator (LDO), an interrupt controller, a serial interface (such as a serial peripheral interface (SPI), an inter-integrated circuit (I 2 C) or general programmable serial interface module), real-time clock (RTC), timer counters (including interval and watchdog timers), general input and output (IO), memory card controller (such as secure digital / multimedia card (SD / MC)), universal serial bus (USB) interface, mobile industry processor interface (MIPI) interface and joint test access group (JTAG) test access port.

[0064] In some aspects, baseband module 310 may be implemented as, for example, a solder-down substrate including one or more integrated circuits, a single packaged integrated circuit soldered to a main circuit board, and / or a multi-chip module containing two or more integrated circuits.

[0065] Figure 4 A base station according to some aspects is shown. In some embodiments, the base station 400 may be or may be configured to operate as an evolved Node B (eNB). In some embodiments, the base station 400 may be or may be configured to operate as a generation Node B (gNB). In some embodiments, the base station 400 may be arranged to operate according to a new radio (NR) protocol. In some embodiments, the base station 400 may be arranged to operate according to a third generation partnership protocol (3GPP) protocol. It should be noted that in some embodiments, the base station 400 may be a fixed, non-mobile device. In some embodiments, the base station 400 may be suitable for use as an eNB 104 as shown in Figure 1. In some embodiments, the base station 400 may be suitable for use as a gNB 105 as shown in Figure 1. It should be noted that in some embodiments, the eNB, an apparatus of an eNB, a gNB, an apparatus of a gNB, a base station and / or an apparatus of a base station may include Figure 2 , Figure 4 and Figure 5 In some embodiments, such an eNB, gNB, base station and / or device may include one or more additional components.

[0066] Figure 4A base station or infrastructure equipment radio head 400 is shown according to one aspect. The base station 400 may include one or more of an application processor 405, a baseband module 410, one or more wireless front end modules 415, a memory 420, a power management circuit 425, a power tee circuit 430, a network controller 435, a network interface connector 440, a satellite navigation receiver module 445, and a user interface 450. In some aspects, the base station 400 may be an evolved Node B (eNB), which may be arranged to operate according to a 3GPP protocol, a new radio (NR) protocol, and / or a fifth generation (5G) protocol. In some aspects, the base station 400 may be a generation Node B (gNB), which may be arranged to operate according to a 3GPP protocol, a new radio (NR) protocol, and / or a fifth generation (5G) protocol.

[0067] In some aspects, the application processor 405 may include one or more CPU cores and one or more cache memories, a low dropout regulator (LDO), an interrupt controller, a serial interface (such as SPI, I 2 C or general programmable serial interface module), real-time clock (RTC), timer counters (including interval and watchdog timers), general IO, memory card controller (such as SD MMC, etc.), USB interface, MIPI interface and Joint Test Access Group (JTAG) test access port.

[0068] In some aspects, baseband processor 410 may be implemented as, for example, a solder-in substrate including one or more integrated circuits, a single packaged integrated circuit soldered to a main circuit board, or a multi-chip module containing two or more integrated circuits.

[0069] In some aspects, memory 420 may include one or more of the following: volatile memory including dynamic random access memory (DRAM) and / or synchronous dynamic random access memory (SDRAM); and non-volatile memory (NVM) including high-speed electrically erasable memory (commonly referred to as flash memory), phase change random access memory (PRAM), magnetoresistive random access memory (MRAM), and / or three-dimensional cross-point memory. Memory 420 may be implemented as one or more of a solder-in package integrated circuit, a socket memory module, and a plug-in memory card.

[0070] In some aspects, the power management integrated circuit 425 can include one or more of a voltage regulator, a surge protector, a power alert detection circuit, and one or more backup power sources (such as a battery or capacitors). The power alert detection circuit can detect one or more of a brownout (undervoltage) and a surge (overvoltage) condition.

[0071] In some aspects, the power tee 430 can provide electrical power drawn from the network cable to provide both power and data connectivity to the base station 400 using a single cable. In some aspects, the network controller 435 can provide connectivity to the network using a standard network interface protocol such as Ethernet. The network connectivity can be provided using a physical connection that is one of electrical (commonly referred to as a copper interconnect), optical, or wireless.

[0072] In some aspects, the satellite navigation receiver module 445 may include circuits for receiving and decoding signals transmitted by one or more navigation satellite constellations, such as the Global Positioning System (GPS), Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS), Galileo, and / or BeiDou. The receiver 445 may provide data to the application processor 405, which may include one or more of position data or time data. The application processor 405 may use the time data to synchronize operations with other wireless base stations. In some aspects, the user interface 450 may include one or more physical or virtual buttons, such as a reset button, one or more indicators, such as a light emitting diode (LED), and a display screen.

[0073] Figure 5 500 is shown for illustrative purposes and may include Figure 5 Other components not shown in the figure. In some aspects, the communication circuit 500 can be used for millimeter wave communication, but the aspect is not limited to millimeter wave communication. In some aspects, the communication circuit 500 can perform communication at any suitable frequency.

[0074] It should be noted that in some aspects, devices such as UE 102, eNB 104, gNB 105, user equipment 300, base station 400, machine 200 and / or other devices may include one or more components of the communication circuit 500.

[0075] The communication circuit 500 may include a protocol processing circuit 505 that may implement one or more of a medium access control (MAC), a radio link control (RLC), a packet data convergence protocol (PDCP), a radio resource control (RRC), and a non-access stratum (NAS) function. The protocol processing circuit 505 may include one or more processing cores (not shown) for executing instructions and one or more memory structures (not shown) for storing program and data information.

[0076] The communication circuit 500 may further include a digital baseband circuit 510, which may implement a physical layer (PHY) function, including a hybrid automatic repeat request (HARQ) function, scrambling and / or descrambling, encoding and / or decoding, layer mapping and / or demapping, modulation symbol mapping, received symbol and / or bit metric determination, multi-antenna port precoding and / or decoding (which may include one or more of space-time, space-frequency or space coding), reference signal generation and / or detection, preamble sequence generation and / or decoding, synchronization sequence generation and / or detection, control channel signal blind decoding and one or more of other related functions.

[0077] The communication circuit 500 may further include a transmit circuit 515, a receive circuit 520, and / or an antenna array circuit 530. The communication circuit 500 may further include a radio frequency (RF) circuit 525. In one aspect of the present disclosure, the RF circuit 525 may include multiple parallel RF chains for one or more of the transmit or receive functions, each RF chain connected to one or more antennas of the antenna array 530.

[0078] In one aspect of the present disclosure, the protocol processing circuit 505 may include one or more instances of a control circuit (not shown) to provide control functionality for one or more of the digital baseband circuit 510 , the transmit circuit 515 , the receive circuit 520 , and / or the RF circuit 525 .

[0079] In some embodiments, the processing circuitry may perform one or more operations described herein and / or other operations. In a non-limiting example, the processing circuitry may include one or more components, such as the processor 202, the application processor 305, the baseband module 310, the application processor 405, the baseband module 410, the protocol processing circuitry 505, the digital baseband circuitry 510, similar components, and / or other components.

[0080] In some embodiments, the transceiver may transmit one or more elements (including but not limited to those described herein) and / or receive one or more elements (including but not limited to those described herein). In a non-limiting example, the transceiver may include one or more components, such as wireless front end module 315, wireless front end module 415, transmit circuit 515, receive circuit 520, radio frequency circuit 525, similar components, and / or other components.

[0081] One or more antennas (such as 230, 312, 412, 530 and / or other antennas) may include one or more directional or omnidirectional antennas, including, for example, dipole antennas, monopole antennas, patch antennas, loop antennas, microstrip antennas, or other types of antennas suitable for transmitting RF signals. In some multiple-input multiple-output (MIMO) embodiments, one or more antennas (such as 230, 312, 412, 530 and / or other antennas) may be effectively separated to take advantage of spatial diversity and the different channel characteristics that may result.

[0082] In some embodiments, UE 102, eNB 104, gNB 105, user equipment 300, base station 400, machine 200, and / or other devices described herein may be mobile devices and / or portable wireless communication devices, such as personal digital assistants (PDAs), laptop computers or portable computers with wireless communication capabilities, web tablet computers, wireless phones, smart phones, wireless headsets, pagers, instant messaging devices, digital cameras, access points, televisions, wearable devices such as medical devices (e.g., heart rate monitors, blood pressure monitors, etc.), or other devices that can wirelessly receive and / or send information. In some embodiments, UE 102, eNB 104, gNB 105, user equipment 300, base station 400, machine 200, and / or other devices described herein may be configured to operate according to 3GPP standards, but the scope of the embodiments is not limited in this respect. In some embodiments, UE 102, eNB 104, gNB 105, user equipment 300, base station 400, machine 200, and / or other devices described herein may be configured to operate according to a new radio (NR) standard, but the scope of the embodiments is not limited in this respect. In some embodiments, UE 102, eNB 104, gNB 105, user equipment 300, base station 400, machine 200, and / or other devices described herein may be configured to operate according to other protocols or standards, including IEEE 802.11 or other IEEE standards. In some embodiments, UE 102, eNB 104, gNB 105, user equipment 300, base station 400, machine 200, and / or other devices described herein may include one or more of a keyboard, a display, a non-volatile memory port, multiple antennas, a graphics processor, an application processor, a speaker, and other mobile device elements. The display may be an LCD screen including a touch screen.

[0083] Although UE 102, eNB 104, gNB 105, user equipment 300, base station 400, machine 200 and / or other devices described herein may be shown as having several separate functional elements, one or more functional elements may be combined and may be implemented by a combination of software-configured elements (such as processing elements including digital signal processors (DSPs)) and / or other hardware elements. For example, some elements may include one or more microprocessors DSPs, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), radio frequency integrated circuits (RFICs), and combinations of various hardware and logic circuits for performing at least the functions described herein. In some embodiments, a functional element may refer to one or more processes operating on one or more processing elements.

[0084] Embodiments may be implemented in one or a combination of hardware, firmware, and software. Embodiments may also be implemented as instructions stored on a computer-readable storage device, which may be read and executed by at least one processor to perform the operations described herein. A computer-readable storage device may include any non-transient mechanism for storing information in a machine (e.g., computer) readable form. For example, a computer-readable storage device may include a read-only memory (ROM), a random access memory (RAM), a disk storage medium, an optical storage medium, a flash memory device, and other storage devices and media. Some embodiments may include one or more processors or may be configured with instructions stored on a computer-readable storage device.

[0085] It should be noted that in some embodiments, the apparatus used by UE 102, eNB 104, gNB 105, machine 200, user equipment 300 and / or base station 400 may include Figure 2-5 104. Thus, the techniques and operations described herein involving UE 102 may be applicable to the apparatus of UE. Additionally, the techniques and operations described herein involving eNB 104 may be applicable to the apparatus of eNB. Additionally, the techniques and operations described herein involving gNB 105 may be applicable to the apparatus of gNB.

[0086] Figure 6 An example of a radio frame structure according to some embodiments is shown. Fig. 7A and Figure 7B 7 may include Fig. 7A and Figure 7B It should be noted that Figure 6 The examples shown in -7 may in some cases illustrate some or all of the concepts and techniques described herein, but the embodiments are not limited to these examples. For example, the embodiments are not limited to Figure 6-7. Although the time resources, symbol periods, frequency resources, PRBs and other elements shown in the name, number, type, size, order, arrangement and / or other aspects of the restrictions. Figure 6 -Some elements shown in the example of 7 may be included in the 3GPP LTE standard, the 5G standard, the NR standard and / or other standards, but the embodiments are not limited to the use of these elements included in the standards.

[0087] An example of a radio frame structure that may be used in some aspects is Figure 6 . In this example, the radio frame 600 has a duration of 10 ms. The radio frame 600 is divided into time slots 602, each time slot lasting 0.5 ms and numbered from 0 to 19. In addition, each pair of adjacent time slots 602 numbered 2i and 2i+1 is called a subframe 601, where i is an integer.

[0088] In some aspects, using Figure 6 In the radio frame format of , each subframe 601 may include a combination of one or more of downlink control information, downlink data information, uplink control information, and uplink data information. A combination of information type and direction may be independently selected for each subframe 602.

[0089] refer to Fig. 7A and Figure 7B In some aspects, a subcomponent of a transmitted signal consisting of one subcarrier in the frequency domain and one symbol interval in the time domain may be referred to as a resource element. A resource element may be represented by Fig. 7A and Figure 7B The grid form shown in is depicted.

[0090] In some aspects, such as Fig. 7A As shown in , resource elements can be grouped into rectangular resource blocks 700, which consist of 12 subcarriers in the frequency domain and P symbols in the time domain, where P can correspond to the number of symbols contained in a time slot and can be 6, 7, or any other suitable number of symbols.

[0091] In some alternative aspects, such as Figure 7B As shown in , resource elements may be grouped into a resource block 700, which consists of 12 subcarriers in the frequency domain (as shown by 702) and one symbol in the time domain. Fig. 7A and Figure 7B In the depiction of , each resource element 705 may be indexed as (k, 1), where k is the index number of the subcarrier in the range of 0 to N·M-1 (as shown by 703), where N is the number of subcarriers in the resource block and M is the number of resource blocks across the component carrier in the frequency domain.

[0092] According to some embodiments, UE 102 may select a short transmission time interval (TTI) for vehicle-to-vehicle (V2V) sidelink transmission of UE 102 from a plurality of short TTIs. The short TTI may occur in a traditional TTI. The short TTI may be allocated for V2V sidelink transmission by non-traditional UE 102. The traditional TTI may be allocated for V2V sidelink transmission by traditional UE 102. UE 102 may send a traditional physical sidelink control channel (PSCCH) according to the traditional TTI to indicate the V2V sidelink transmission of the traditional UE 102 to UE 102. UE 102 may send a short PSCCH (sPSCCH) according to the selected short TTI to indicate the V2V sidelink transmission of UE 102 to the non-traditional UE 102. These embodiments are described in more detail below.

[0093] Figure 8 Operations of communication methods according to some embodiments are shown. In describing method 800, reference may be made to one or more of Figures 1-23, but it is understood that method 800 may be implemented with any other suitable systems, interfaces, and components. In some cases, descriptions herein of one or more concepts, operations, and / or techniques of one of the methods described herein (800 and / or others) may be applicable to at least one other method described herein (800 and / or others).

[0094] Some embodiments of method 800 may include Figure 8 Additional operations compared to the operations shown in , including but not limited to the operations described herein. Some embodiments of method 800 may not necessarily include Figure 8 In addition, the embodiments of method 800 need not be limited to Figure 8 In some embodiments, UE 102 may perform one or more operations of method 800, but embodiments are not limited to the execution of method 800 and / or the operations thereof by UE 102. Therefore, although reference may be made to the execution of one or more operations of method 800 by UE 102 in the description herein, it should be understood that in some embodiments, gNB 105 and / or eNB 104 may perform one or more operations as follows, which may be the same, similar and / or interact with one or more operations of method 800.

[0095] Although the method 800 and other methods described herein may refer to an eNB 104, gNB 105, or UE 102 operating according to 3GPP standards, 5G standards, NR standards, and / or other standards, embodiments of these methods are not limited to those eNBs 104, gNBs 105, or UEs 102, and may also be implemented on other devices, such as Wi-Fi access points (APs) or user stations (STAs). In addition, the method 800 and other methods described herein may be practiced by wireless devices configured to operate in other suitable types of wireless communication systems, including systems configured to operate according to various IEEE standards such as IEEE 802.11. The method 800 and other methods described herein may also be applicable to a device of a UE 102, a device of an eNB 104, a device of a gNB 105, and / or a device of another device described above.

[0096] It should also be noted that the embodiments are not limited by reference herein (such as, the description of the method and / or other descriptions herein) to transmit, receive and / or exchange elements such as frames, messages, requests, indicators, signals or other elements. In some embodiments, such elements can be generated, encoded or otherwise processed by a processing circuit (such as by a baseband processor included in the processing circuit) for transmission. In some cases, the transmission can be performed by a transceiver or other components. In some embodiments, such elements can be decoded, detected or otherwise processed by a processing circuit (such as by a baseband processor). In some cases, the element can be received by a transceiver or other components. In some embodiments, the processing circuit and the transceiver can be included in the same device. However, in some embodiments, the scope of the embodiments is not limited in this respect, because the transceiver can be separated from the device including the processing circuit.

[0097] One or more of the messages described herein may be included in a standard and / or protocol, including but not limited to the 3rd Generation Partnership Project (3GPP), 3GPP Long Term Evolution (LTE), 4th Generation (4G), 5th Generation (5G), New Radio (NR), and / or other. However, the scope of the embodiments is not limited to the use of elements included in the standard.

[0098] At operation 805, UE 102 may receive one or more control messages indicating an allocation of a resource pool for V2V sidelink transmission. In some embodiments, one or more control messages may be received from eNB 104 and / or gNB 105, but the scope of the embodiments is not limited in this respect. Any suitable control message may be used.

[0099] In some embodiments, one or more control messages may include information related to allocation of resource pools for V2V sidelink transmissions. In some embodiments, such information may be related to one or more operations described herein. In some embodiments, such information may be related to one or more of: transmission time interval (TTI), short TTI, configuration of TTI, configuration of short TTI, resource pool, channel sensing, sensing window, resource selection window, resource (re)selection window, and / or other concepts (including but not limited to those described herein).

[0100] In some embodiments, a resource pool may be allocated for V2V side link transmission. In some embodiments, multiple resource pools may be allocated for V2V side link transmission. In some embodiments, eNB 104 and / or gNB 105 may allocate one or more resource pools, but the scope of the embodiments is not limited in this regard. Thus, eNB 104 and / or gNB 105 may send one or more control messages indicating information related to resource pools. In some embodiments, one or more resource pools may be allocated for V2V side link transmission according to 3GPP standards and / or other standards, but the scope of the embodiments is not limited in this regard.

[0101] It should be noted that some embodiments may not necessarily include operation 805. In a non-limiting example, the resource pool for V2V sidelink transmission may be pre-configured, pre-defined, included in the standard, and / or other. In these and other scenarios, the control message of operation 805 may not be necessary.

[0102] It should be noted that the description herein may refer to V2V sidelink transmission, but the embodiments are not limited to V2V sidelink transmission. One or more operations and / or techniques described herein related to V2V sidelink transmission may be applicable to sidelink transmission that is not necessarily V2V sidelink transmission.

[0103] In some embodiments, the resource pool may include time resources and / or frequency resources. In a non-limiting example, the resource pool may include one or more physical resource blocks (PRBs) and one or more symbol periods (including but not limited to OFDM symbol periods). In another non-limiting example, the resource pool may include one or more subchannels and one or more subframes. In some embodiments, the resource pool may include continuous frequency resources, subchannels and / or PRBs, but the scope of the embodiments is not limited to this aspect. In some embodiments, the resource pool may include continuous time resources, symbol periods and / or subframes, but the scope of the embodiments is not limited to this aspect.

[0104] It should be noted that the description of some operations and / or techniques herein may refer to PRBs, subchannels, symbol periods and / or subframes, but such reference is not restrictive. In some embodiments, other time resources and / or frequency resources may be used in one or more of these operations and / or techniques.

[0105] At operation 810, the UE 102 may determine one or more signal quality or sensing measurements. Non-limiting examples of signal quality measurements include sidelink received signal strength indicator (S-RSSI), received signal strength indicator (RSSI), signal-to-noise ratio (SNR), reference signal received power (RSRP), reference signal received quality (RSRQ), channel busy ratio (CBR), and / or others.

[0106] At operation 815, the UE 102 may select a short transmission time interval (TTI). In some embodiments, the UE 102 may select a short TTI for a vehicle-to-vehicle (V2V) sidelink transmission of the UE 102. In some embodiments, the UE 102 may select a short TTI from a plurality of short TTIs, including but not limited to a plurality of candidate TTIs. In some embodiments, the UE 102 may select and / or use a plurality of short TTIs for one or more V2V sidelink transmissions by the UE 102.

[0107] In some embodiments, short TTIs may be allocated for V2V sidelink transmissions of non-legacy UEs 102, and legacy TTIs may be allocated for V2V sidelink transmissions of legacy UEs 102. It should be noted that reference to non-legacy UEs 102 is not limiting. In some embodiments, enhanced UEs 102, UEs 102 configured for NR operation, UEs 102 configured for 5G operation, and / or other types of UEs 102 may be used. In a non-limiting example, the operations performed by non-legacy UEs 102 in this description may be performed by enhanced UEs 102, UEs 102 configured for NR operation, UEs 102 configured for 5G operation, and / or other types of UEs 102 in some embodiments. In another non-limiting example, some scenarios may include communications between components described herein and non-legacy UEs 102. In some embodiments, the same or similar scenarios may include communications between components and enhanced UEs 102, UEs 102 configured for NR operation, UEs 102 configured for 5G operation, and / or other types of UEs 102.

[0108] In some embodiments, UE 102 may determine one or more signal quality measurements for multiple short TTIs. The signal quality measurements may be determined based on one or more channel sensing operations prior to a traditional TTI, but the scope of the embodiments is not limited in this respect. UE 102 may select a short TTI for V2V sidelink transmission based at least in part on the signal quality measurements for multiple short TTIs.

[0109] It should be noted that reference to "short TTI" is not limiting. In some cases, such reference may be used for clarity. In some embodiments, one or more short TTIs may occur within a traditional TTI. In some embodiments, one or more short TTIs may be within a traditional TTI. In some embodiments, a traditional TTI may include multiple short TTIs. In some embodiments, a traditional TTI may be divided to include multiple short TTIs. A short TTI may be shorter than a traditional TTI, but the scope of the embodiments is not limited in this respect.

[0110] In a non-limiting example, a legacy TTI may be used in accordance with a legacy LTE protocol including but not limited to LTE R14, and a short TTI may be used in accordance with another LTE protocol including but not limited to LTE-Advanced, LTE R15, and / or higher.

[0111] In another non-limiting example, a conventional TTI may span one millisecond (msec), and the plurality of short TTIs may include four short TTIs. In another non-limiting example, a conventional TTI may span one millisecond, and the plurality of short TTIs may include two short TTIs. Embodiments are not limited by these example numbers.

[0112] In another non-limiting example, the short TTI may span multiple symbol periods.At least one of the symbol periods may be based on a demodulation reference signal (DMRS).At least one of the symbol periods may be based on data bits.

[0113] In some embodiments, multiple traditional TTIs may be allocated for V2V sidelink transmissions. In some cases, one or more traditional TTIs may include multiple short TTIs. In some cases, one or more of these short TTIs may be allocated for V2V sidelink transmissions.

[0114] At operation 820, UE 102 may transmit a legacy physical sidelink control channel (PSCCH). In some embodiments, UE 102 may transmit a legacy PSCCH to indicate to legacy UE 102 a V2V sidelink PSSCH transmission of UE 102. It should be noted that embodiments are not limited to the use of a legacy PSCCH in this operation and / or other operations described herein, as any suitable elements may be used. It should be noted that some embodiments may not necessarily include operation 820.

[0115] In some embodiments, UE 102 may send a legacy PSCCH according to a legacy TTI, but the scope of the embodiments is not limited in this respect. In some embodiments, UE 102 may send a legacy PSCCH in a legacy TTI, but the scope of the embodiments is not limited in this respect. In some embodiments, UE 102 may send a legacy PSCCH and a PSSCH within a legacy TTI, but the scope of the embodiments is not limited in this respect.

[0116] At operation 825, UE 102 may send a short PSCCH (sPSCCH). At operation 830, UE 102 may send a short PSSCH (sPSSCH). In some embodiments, UE 102 may send an sPSCCH to indicate the V2V sidelink transmission of UE 102 to non-traditional UE 102. In some embodiments, the V2V sidelink transmission may include the transmission of sPSSCH or PSSCH. However, the embodiments are not limited to the use of sPSSCH or PSSCH, because other elements may be used in some embodiments. It should be noted that in some embodiments, the embodiments are not limited to the use of sPSCCH for operation 825, because other elements (including other types of PSCCH) may be used. In some embodiments, sPSCCH may be included in the 3GPP standard. It should be noted that the embodiments are not limited to the use of sPSCCH in this operation and / or other operations described herein, because any suitable element may be used.

[0117] In some embodiments, UE 102 may send sPSCCH according to the selected short TTI, but the scope of the embodiments is not limited in this respect. In some embodiments, UE 102 may send sPSCCH in the selected short TTI, but the scope of the embodiments is not limited in this respect. In some embodiments, UE 102 may send sPSCCH within the selected short TTI, but the scope of the embodiments is not limited in this respect.

[0118] In some embodiments, multiple sPSCCHs may be sent. For example, multiple short TTIs may be selected, and the UE 102 may send multiple sPSCCHs per short TTI.

[0119] At operation 830, UE 102 may transmit a short physical sidelink shared channel (sPSSCH). In some embodiments, UE 102 may transmit the sPSSCH as part of the V2V sidelink transmission, but the scope of the embodiments is not limited in this respect. It should be noted that in some embodiments, the embodiments are not limited to the use of the sPSSCH for operation 830, as other elements (including other types of PSSCH) may be used. In some embodiments, the sPSSCH may be included in the 3GPP standard. It should be noted that the embodiments are not limited to the use of the sPSSCH in this operation and / or other operations described herein, as any suitable elements may be used.

[0120] In some embodiments, UE 102 may send sPSSCH according to a selected short TTI, but the scope of the embodiments is not limited in this respect. In some embodiments, UE 102 may send sPSSCH with a selected short TT1, but the scope of the embodiments is not limited in this respect. In some embodiments, UE 102 may send sPSSCH within a selected short TT1, but the scope of the embodiments is not limited in this respect.

[0121] In a non-limiting example, UE 102 may send sPSSCH and sPSCCH in separate frequency resources according to frequency division multiplexing (FDM) techniques. In another non-limiting example, UE 102 may send sPSSCH in a short TTI later than the selected short TTI according to time division multiplexing (TDM) techniques.

[0122] In another non-limiting example, the UE 102 may transmit the PSCCH in a first frequency resource allocated for V2V sidelink transmissions by legacy UEs 102. The UE 102 may transmit the sPSCCH in a second frequency resource allocated for V2V sidelink transmissions by non-legacy UEs 102.

[0123] In another non-limiting example, the sPSCCH may include sidelink control information (SCI) indicating first information related to V2V sidelink transmission of UE 102. The legacy PSCCH may include sidelink control information (SCI) format-1 (SCI-F1) indicating second information related to V2V sidelink transmission of UE 102. In some embodiments, the SCI and / or SCI-F1 may indicate resources of the V2V sidelink transmission of UE 102, such as frequency resources (PRBs, subchannels and / or other) and / or time resources (subframes, symbols and / or other).

[0124] At operation 835, UE 102 may send an automatic gain control (AGC) element. In some embodiments, UE 102 may send an AGC element in a first time sequential symbol period of a traditional TTL. In some embodiments, UE 102 may send an AGC element in a first time sequential symbol period of a traditional TTI, regardless of the position of the selected TTI within the traditional TTI. In some embodiments, UE 102 may send an AGC element in a first time sequential symbol period of a subframe. In some cases, the transmission of the AGC element in the first time sequential symbol period may enable the AGC to be correctly set for traditional UE 102 to avoid near-far problems and / or dynamic range saturation problems. In addition, the transmission of the AGC element in the first time sequential symbol period may help reduce the AGC implementation overhead of multiple UEs 102, because the AGC may be established at the beginning of the traditional TTL.

[0125] In some embodiments, the AGC element may be sent to enable AGC at a legacy UE 102. In some embodiments, the AGC element may be sent to enable AGC at a non-legacy UE 102. In some embodiments, the AGC element may be sent to enable AGC at a legacy UE 102 and / or a non-legacy UE 102.

[0126] In some embodiments, the AGC elements may be based on a predetermined sequence, although the scope of the embodiments is not limited in this respect.In some embodiments, the AGC elements may be sent during a symbol period (such as an AGC symbol period) that may be dedicated / reserved for transmission of the AGC elements.

[0127] At operation 840, UE 102 may select a resource pool from the candidate resource pools. In some embodiments, UE 102 may select a resource pool for one or more V2V sidelink transmissions by UE 102. In some embodiments, subframes of different candidate resource pools may be non-overlapping, although the scope of the embodiments is not limited in this respect.

[0128] In some embodiments, candidate resource pools may be allocated for V2V transmissions of different wait times per candidate resource pool, but the scope of the embodiments is not limited in this respect. In some embodiments, UE 102 may select a resource pool from the candidate resource pool based at least in part on: a target wait time for V2V sidelink transmissions of UE 102, and different wait times per candidate resource pool. For example, UE 102 may select a resource pool whose corresponding wait time is the same and / or closest to the target wait time of UE 102. In a non-limiting example, a first resource pool may be allocated for V2V sidelink transmissions of relatively high wait times, and a second resource pool may be allocated for V2V sidelink transmissions of relatively low wait times. For example, a relatively low wait time may be 20 milliseconds or less, but any suitable range of relatively low wait times may be used.

[0129] It should be noted that some embodiments may not necessarily include operation 840. For example, in some embodiments, a single resource pool may be used, in which case operation 840 may not be selected.

[0130] At operation 845, UE 102 may monitor a sensing window for V2V sidelink transmissions. In some embodiments, the sensing window may occur before the selected resource pool. In some embodiments, UE 102 may attempt to detect V2V sidelink transmissions of other UEs 102 during the sensing window. In some embodiments, candidate resource pools may be configured for sensing and / or resource selection windows of different durations.

[0131] In some embodiments, UE 102 may determine one or more signal quality measurements during the sensing window. Non-limiting examples of signal quality measurements include S-RSSI, SNR, RSRP, RSRQ, and / or others. In some embodiments, the resource pool may include multiple physical resource blocks (PRBs) and / or subchannels per subframe, and the wireless measurement may include a channel busy ratio (CBR). In a non-limiting example, the CBR may be based at least in part on the ratio of PRBs / subchannels during the subframe window as follows: the total number of PRBs / subchannels for which the signal quality measurement is above a threshold, and the ratio of the total number of PRBs / subchannels.

[0132] At operation 850, the UE 102 may determine one or more available subframes. At operation 855, the UE 102 may select one or more subframes based on the available subframes. At operation 860, the UE 102 may transmit the PSSCH in the selected subframes.

[0133] In some embodiments, UE 102 may determine one or more candidate subframes of a resource selection window that UE 102 may use for V2V sidelink transmission. In a non-limiting example, one or more SCIs included in the detected V2V sidelink transmission may be used to determine the candidate subframes. In another non-limiting example, one or more signal quality measurements (including but not limited to signal quality measurements determined during a sensing window) may be used to determine the candidate subframes. In some embodiments, the resource selection window may be after the sensing window. In a non-limiting example, the duration of the resource selection window may be less than or equal to 10 subframes, or may be determined by a packet transmission wait time or may be configured by a higher layer of the UE. The embodiments are not limited to this example number, as any size may be used to select a window. It should be noted that the resource selection window may be related to one or more of: selection of resources, reselection of resources, and / or other.

[0134] In some embodiments, UE 102 may select one or more subframes in the resource selection window from the candidate subframes for V2V sidelink transmission by UE 102. UE 102 may send a PSSCH based on a data bit block in the selected subframes.

[0135] In some embodiments, UE 102 may select one or more subframes for V2V sidelink transmission by UE 102 in a plurality of selection windows shifted in time. In some embodiments, UE 102 may select one or more subframes for V2V sidelink transmission by UE 102 to include the earliest candidate subframe in the resource selection window. In some cases, this selection technique may be referred to as "first time" selection, etc., but is not limited thereto.

[0136] It should be noted that some embodiments may not necessarily include Figure 8 In a non-limiting example, some operations may include one or more of operations 805-835, but may not necessarily include one or more of operations 840-855. In another non-limiting example, some operations may include one or more of operations 840-855, but may not necessarily include one or more of operations 805-835. In another non-limiting example, in an embodiment that does not use short TTI, method 800 may not necessarily include one or more of operations 805-835.

[0137] In some embodiments, the device of UE 102 may include a memory. The memory may be configured to store information identifying the selected short TTI. The memory may store one or more other elements, and the device may use them to perform one or more operations. The device may include a processing circuit that may perform one or more operations (including but not limited to the operations of method 800 and / or other methods described herein). The processing circuit may include a baseband processor. The baseband circuit and / or the processing circuit may perform one or more operations described herein, including but not limited to selecting a short TTI for V2V transmission. The device of UE 102 may include a transceiver for sending an sPSCCH. The transceiver may send and / or receive other blocks, messages, and / or other elements.

[0138] Figure 9-11 An example multiplexing arrangement is shown that may be used in accordance with some embodiments. Figure 12-17 Example arrangements that may be used according to various transmission time intervals (TTIs) in accordance with some embodiments are shown. Figures 18-19 illustrate example resource allocations that may be used in accordance with some embodiments. Figure 20-23 Example techniques for resource selection according to some embodiments are shown.

[0139] It should be noted that Figure 9-23 The examples shown in the examples may in some cases illustrate some or all of the concepts and techniques described herein, but the embodiments are not limited by these examples. For example, the embodiments are not limited by Figure 9-23 The operations, messages, time intervals, symbols, names, numbers, types, sizes, orderings, arrangements, and / or other aspects of the eNB 104, gNB 105, UE 102, and other elements shown in the specification are not limited. Figure 9-23 Some of the elements shown in the examples may be included in the 3GPP LTE standard, the 5G standard, the NR standard, and / or other standards, but the embodiments are not limited to the use of these elements included in the standards.

[0140] In some embodiments, sidelink communications based on a transmission time interval (TTI) may be used. In a non-limiting example, 3GPP LTE protocols (including but not limited to LTE Release 14) may use sidelink communications based on a TTI of one millisecond (msec). In some embodiments, periodic broadcast vehicle-to-vehicle (V2V) communications may be used. In a non-limiting example, a period of 100 milliseconds may be used.

[0141] In some embodiments, vehicle-to-everything (V2X) communications may be used based on unicast communications, multicast communications, communications within a vehicle platoon, and / or other communications. In some cases, communications may be performed based on latency in the range of 10 to 20 milliseconds, but the scope of the embodiments is not limited in this respect.

[0142] In some embodiments, LTE sidelink communications with a short transmission time interval (S-TTI) of less than one millisecond may be used. This TTI may be referred to herein as a "short TTI," but such reference is not limiting. In some cases, such reference may be used for clarity. In some scenarios, the use of short TTI transmissions may support V2X use cases based at least in part on LTE V2V designs and specifications.

[0143] In some embodiments, short TTI support in LTE may include several design options, some of which are described herein. In some scenarios, coexistence of short TTI communications with LTE R14 resource pools and designs may be achieved. In some embodiments, short TTI operation on a dedicated carrier may be used, where a short TTI physical structure may be used. In some cases, various techniques may be used to address potential near-far scenarios for short TTI coexistence with R14 LTE-V2V communications using the same and / or overlapping resource pools.

[0144] In some embodiments, enhanced communications using short TTI (S-TTI) can coexist with traditional LTE V2V communications (legacy TTI (L-TTI) with 1 millisecond duration) using the same resource pool as defined in LTE R14. Several scenarios of S-TTI usage with respect to L-TTI operation are possible, including but not limited to the scenarios described below. For clarity, these scenarios may be referred to herein as "Scenario 1", "Scenario 2", "Scenario 3", and "Scenario 4", but these references are not limiting.

[0145] In scenario 1, with a traditional sidelink control channel (PSCCH, SCI-F1) transmission, S-TTI and L-TTI in a traditional resource pool (LTE R14) can coexist. In this scenario, S-TTI and L-Tll transmissions can share the same resource pool. An enhanced UE 102 (such as R1S+) can communicate with other enhanced UEs 102 using S-TTI, and can send a traditional PSCCH, SCI-Format 1, so that it can be received / decoded by a traditional UE 102 (such as R14) and used for sensing and resource selection.

[0146] In scenario 2, S-TTI and L-TTI in the traditional resource pool can coexist without PSCCH SCI-Format 1 transmission. In this scenario, S-TTI and L-TTI transmissions can share the same resource pool. The enhanced UE 102 can communicate with other enhanced UEs 102 using S-TTI, but it is not necessary to send the traditional SCI-F1. In this case, the traditional UE 102 may not be aware of potential S-TTI transmissions, and therefore may not be able to consider these S-TII transmissions after traditional sensing and resource selection (e.g., resource exclusion steps). Energy sensing (S-RSSI measurement) and / or resource sorting (including but not limited to the technology of LTE R14 protocol) can still be used to avoid conflicts with S-TTI transmissions. However, in some cases, it may still be impossible to distinguish the priorities signaled in SCI-Format 1.

[0147] In scenario 3, with SCI-Format 1 transmission enabled, S-TTI and L-TTI transmissions may use different resource pools. In this scenario, when legacy (R14) and enhanced UEs 102 do not share resource pools, there may not necessarily be coexistence / compatibility issues because different pools are used for S-TTI and L-TTI transmissions. From a coexistence point of view, it may not be necessary to use SCI-Format 1 transmissions by enhanced UEs 102. However, in some cases, at least in terms of time resources, enhanced UEs 102 may use SCI-Format 1 transmissions for entire subframe reservations.

[0148] In scenario 4, S-TTI and L-TTI transmissions may use different resource pools without SCI-F1 transmission. In this scenario, there may not necessarily be coexistence / compatibility issues. The enhanced UE 102 may benefit from reduced latency. However, when utilizing S-TTI, half-duplex and in-band transmission effects may reduce the link budget.

[0149] In some cases, scenarios 3 and 4 may be considered as scenarios with enhanced UE 102 in green area deployment without compatibility considerations. In some cases, scenario 4 may be considered promising in terms of improved performance. Scenario 1 and scenario 2 may have multiple technical challenges, including but not limited to challenges related to control channel design, AGC setup interval design, S-TTI physical structure for PSCCH (sPSCCH) and PSSCH (sPSSCH). In some cases, one or more techniques described herein may address these issues.

[0150] Some techniques described herein may relate to short TTI control channel design, although the scope of the embodiments is not limited in this respect.

[0151] In some embodiments, in addition to the sPSSCH sidelink shared channel, dedicated control signaling and channels (e.g., sPSCCH) for S-TTI may also be defined. In some embodiments, sPSCCH and sPSSCH may follow similar resource configuration principles as defined for legacy UE 102 and may have similar S-TTI physical structures, but the scope of the embodiments is not limited in this regard. In some cases, the number of sPSCCH and sPSSCH subchannels may be reduced compared to legacy systems. For example, in some cases, broadband transmission may be more typical in the case of S-TTI operation.

[0152] refer to Fig. 9 In example scenario 900, during S-TTI 910, sPSCCH transmission 920 may be multiplexed with sPSSCH transmission 925 in the frequency domain. Fig. 9 In example scenario 950, sPSCCH transmission 970 may be multiplexed in the time domain with sPSSCH transmission 975. In some cases, a dedicated S-TTI 960 may be allocated for multiple sPSCCH transmissions.

[0153] In some cases, the support of S-TTI in the same resource pool used by conventional transmission may have a significant impact on the sensing and resource selection process (including but not limited to the process of conventional LTE and / or LTE R14). In some cases (including but not limited to scenario 1 and scenario 2), this impact may be different depending on whether the enhanced UE 102 sends SC1-Format 1.

[0154] In some embodiments, SCI-Format 1 may be sent by the enhanced UE 102. In scenario 1, the enhanced UE 102 may send SCI-Format 1 using L-TTI (e.g., according to the legacy PSCCH physical structure and SCI design). In some cases, sPSSCH data may be sent in an S-TTI allocation. In some cases, additional SCI control signaling may be sent within an S-TTI PSCCH allocation (sPSCCH).

[0155] Fig.10 Scenario 1000 in FIG. 1 shows a non-limiting example of multiplexing of legacy and enhanced PSCCH / PSSCH. Scenario 1000 may be applicable to Scenario 1, but the scope of the embodiments is not limited in this respect.

[0156] In some embodiments, in the case of successful SCI-Format 1 reception, the legacy UE 102 may potentially detect the presence of the transmission of the enhanced UE 102, and thus this information may be taken into account for resource selection. In some cases, as part of the R14 sensing and resource selection process, one or more of the PSSCH-RSRP measurement and the S-RSSI measurement may be affected. For the PSSCH-RSRP measurement, if the enhanced UE 102 does not send all four DMRS per subframe, the PSSCH-RSRP measurement may be affected (such as bias and / or other). In some cases, the measurement may not be applicable to S-TTI transmissions. However, if at least one DMRS is sent in the S-TTI according to the R14 format, the resource exclusion step of the resource selection process may be applied. In some cases, the PSSCH-RSRP measurement may be degraded. For the S-RSSI measurement, if the enhanced UE 102 sends in the S-TTI portion of the subframe, the S-RSSI measurement may be affected (such as bias and / or other).

[0157] In some embodiments, if sensing-based S-TTI resource selection is used, the following techniques may be used for enhanced UE 102 and / or R15 UE 102. In a non-limiting example, sPSSCH-RSRP and / or S-RSSI measurements allocated per S-TTI may be used. In some cases, S-TT1 resource allocations may be selected for transmission based at least in part on such measurements.

[0158] In some embodiments, SCI-F1 may not necessarily be sent by the enhanced UE 102 . Fig.10 Scenario 1050 in FIG. 1 shows a non-limiting example of multiplexing of legacy and enhanced PSCCH / PSSCH. Scenario 1050 may be applicable to Scenario 2, but the scope of the embodiments is not limited in this respect.

[0159] In scenario 2, the traditional SCI-F1 is not sent by the enhanced UE 102. In some cases, sPSSCH data may be sent in the S-TTI allocation, and additional SCI control signaling may also be carried within the S-TTI allocation. In some cases, the traditional sensing and resource selection process may be more affected. One or more of the following may be affected on the traditional sensing and resource selection: priority support, PSSCH-RSRP measurement, S-RSSI measurement and / or other. For priority support, information about short TTI transmission priority may not be available to the traditional UE 102, and therefore the transmission priority of the enhanced UE 102 may not necessarily be respected by the traditional sensing and resource selection process. On the other hand, the enhanced UE 102 can respect the priority of the traditional transmission, and therefore there may be no problem from a traditional performance perspective.

[0160] For PSSCH-RSRP measurement, this measurement may not be available for S-TTI transmission.Thus, in some cases, the resource exclusion step of the resource selection process may not necessarily be applied appropriately.

[0161] For S-RSSI measurement, the measurement may be affected similarly to scenario 1 (such as biasing and / or others). In some cases, the ranking and resource selection process can help exclude high energy resources occupied by S-TTI transmissions.

[0162] In some embodiments, the transmission of SCI-F1 in conjunction with a short TTI may reduce the latency benefit that may be provided by a short TTI in the case where an enhanced UE 102 decodes SCI-F1 in order to decode the sPSSCH. However, the system may be designed in such a way that SCI-F1 is sent to legacy UEs 102 primarily for compatibility considerations, while for enhanced UEs 102, an additional sPSCCH may be defined. With the introduction of S-TTI control and shared channels, the latency benefit of S-TTI transmission may be retained for V2V communications in some cases. Fig.11 Scenario 1100 in FIG. 1 shows a non-limiting example of multiplexing of legacy and enhanced PSCCH / PSSCH. Scenario 1100 may be related to compatibility and / or latency reduction considerations, but the scope of the embodiments is not limited in this regard. In some cases, for compatibility reasons, the legacy PSCCH (indicated by 310) may be directed to a legacy UE 102. In some cases, the sPSCCH (indicated by 315) may be directed to an enhanced UE 102 to reduce latency.

[0163] In some cases, AGC dynamic range, implementation overhead and / or other issues may be considered. In a non-limiting example, the near-far problem may be related to the AGC dynamic range. Multiplexing S-TTI and L-TTI transmissions in the same subframe may have a significant impact on the demodulation performance of legacy UE 102. For example, when a legacy UE 102 receives data from a remote legacy transmitter and a nearby enhanced UE 102 triggers an S-TTI transmission starting in the middle of a subframe, important near-far problems may occur in legacy UE 102 reception. It may not be expected that legacy UE 102 adjusts AGC in time at each symbol or according to S-TTI granularity. This problem may cause significant nonlinear distortion and may potentially affect the reception of legacy UE 102 and / or R14 UE 102.

[0164] In some embodiments, the enhanced UE 102 may use one or more of the following transmission options. In some cases, such options may alleviate the dynamic range issues of the legacy UE 102. In a first option, the enhanced UE 102 may use multiple S-TTIs within a subframe. In some cases, this may reduce latency and / or improve reliability. In some cases, multiple enhanced UEs 102 may be multiplexed in the frequency domain. In this case, the legacy UE 102 may use the first symbol in the subframe to establish its AGC parameters according to the legacy behavior. Fig.11 Scene 1130 in shows a non-limiting example of the first option.

[0165] In a second option, the enhanced UE 102 may transmit a signal in the first symbol of a subframe. In some cases, this may enable the legacy UE 102 to establish its AGC based on the maximum expected level of the received power range within the subframe. Fig.11 Scenario 1160 in FIG. 1 shows a non-limiting example of the first option. During the first symbol of subframe 1165, an AGC training symbol (indicated by 1175) is sent.

[0166] In some embodiments, a dedicated region within each S-TTI may be defined. In some cases, this may enable the enhanced UE 102 to accurately establish the AGC before each S-TTI reception.

[0167] In some embodiments, a legacy UE 102 and / or R14 UE 102 may assume one symbol for AGC setup time. If the same assumption is maintained in the case of S-TTI, the AGC implementation overhead may grow significantly depending on the number of S-TTIs within a subframe. For legacy UE 102, the AGC implementation overhead may be one symbol per subframe. For enhanced UE 102, the AGC implementation overhead may be increased to the amount of S-TTI per subframe. One or more of the following techniques may be used to reduce the AGC overhead. In a first technique, faster AGC convergence may be used. For example, for enhanced UE 102, the AGC convergence time within the CP duration may be desired. In a second technique, the first symbol of a subframe may be used for AGC training. A UE 102 that plans to occupy the S-TTI portion of a subframe may send an additional signal for AGC setup at the beginning of each subframe (e.g., the first symbol of a subframe may be an AGC training symbol), regardless of the allocation of S-TTIs within the subframe. This approach may enable AGC operation at a sub-frame rate, may reduce AGC implementation overhead, and / or may result in AGC behavior that is consistent with legacy UE 102 behavior.

[0168] In some embodiments, one or more of the following signals may be used for AGC training. In a non-limiting example, a dedicated preamble or reference signal may be used. Some or all UEs 102 may send the same signal. In some cases, the signal may be predefined in the specification and / or configured by the network / eNB 104. In another non-limiting example, a demodulation reference signal (DM-RS) may be used. Each UE 102 may randomly select a specific sequence from a predefined set of DM-RS sequences. In another non-limiting example, sPSSCH / sPSCCH data may be used. Resources for AGC establishment may be used for data transmission. In this case, data symbols may be used as AGC training sequences. In some embodiments, depending on the convergence time, the sequence may or may not be punctured at the receiver. In another non-limiting example, a copy of the data symbol from sPSSCH / sPSCCH may be used. In this case, depending on the AGC convergence time of a given subframe, the symbols used for AGC establishment may be combined or not combined for data reception. Copies of data symbols allocated from S-TTI may be used as AGC training symbols.

[0169] Various options for short TTI are presented below. Embodiments are not limited to these options. These options include different sized slot and sub-slot level S-TTI physical structures for sPSCCH and sPSSCH channels.

[0170] For each S-TTI pattern, a set of basic S-TTI patterns may employ a fixed number of symbols. The S-TTI pattern may consist of a demodulation reference signal (DM-RS) and data symbols, which may carry information of any defined sidelink channel (including but not limited to a control channel (PSCCH), a shared channel (PSSCH), a broadcast channel (PSBCH), a discovery channel (PSDCH), and / or others).

[0171] A non-limiting example of an S-TTI mode is Fig.12 and 13 Embodiments are not limited to the number of DMRS symbols, the number of PSSCH symbols, the arrangement of DMRS symbols and PSSCH symbols, the ordering of DMRS symbols and PSSCH symbols, or other aspects of the examples. Fig.12 and Fig.13The examples shown in are not exhaustive. In some embodiments, additional patterns similar to those shown may be used. In some embodiments, one or more data symbols from any basic pattern may be punctured. In some embodiments, one or more data symbols from any basic pattern may be used to transmit other signals (including but not limited to AGC training signals, ranging / positioning reference signals, and / or other). In some embodiments, a symmetric S-TTI pattern may be considered as a candidate for an LTE S-TTI sidelink physical structure. In a non-limiting example, such a structure may include a range of symbols from 1 to 7. S-TTI structures for larger numbers of symbols may be based on aggregation of S-TTI patterns, including but not limited to Fig.12 and Fig.13 The example schema shown in .

[0172] It should be noted that in the example shown and in other embodiments, one or more data symbols may also include resource elements (REs) occupied by demodulation reference signals (DM-RS REs). For example, as shown in 1200, PSSCH 1202 may include DMRS 1206 and data signals 1204. This arrangement may be extended to Fig.12 and 13 Symbols in other examples of , but the scope of the embodiments is not limited in this respect. Example 1200 can be a basic S-TTI pattern of size 1. Basic S-TTI patterns of lengths from 2 to 7 are shown in Error! Reference source not found. The basic S-TTI pattern set can be further extended using a cascade / combination of one or more basic S-TTI patterns.

[0173] exist Fig.12 In example 1210 of FIG. 1 , two patterns 1211 and 1215 are shown. Pattern 1211 includes PSSCH 1212 followed by DMRS 1213. Pattern 1215 includes DMRS 1216 followed by PSSCH 1217. Fig.12 , three example patterns 1221, 1222, and 1223 are shown. Each of these patterns includes three symbols (one DMRS symbol and two PSSCH symbols). Various orderings of DMRS symbols and PSCCH symbols are shown.

[0174] exist Fig.13 In FIG. 1 , four example patterns 1300, 1301, 1302, and 1303 are shown. Each of these patterns includes four symbols. Patterns 1300 and 1301 include one DMRS symbol and three PSSCH symbols. Patterns 1302 and 1303 include two DMRS symbols and two PSSCH symbols. Fig.13, four example patterns 1310, 1311, 1312, and 1313 are shown. Each of these patterns includes five symbols. Patterns 1310 and 1311 include one DMRS symbol and four PSSCH symbols. Patterns 1312 and 1313 include two DMRS symbols and three PSSCH symbols. Patterns including three or more DMRS symbols are also possible.

[0175] In some embodiments, patterns of more than five symbols are possible. Various numbers of DMRS symbols and PSSCH symbols may be used. Various orderings / arrangements of DMRS and PSSCH symbols may be used.

[0176] In some embodiments, an S-TTI structure of size m may include k AGC setup symbols. It may be constructed using a basic S-TTI structure of size mk. For example, an S-TTI of size 4 with one AGC setup symbol may be constructed using a basic S-TTI pattern of size 3 and one AGC symbol appended to the beginning of the basic S-TTI pattern. Fig.14 An example of this is shown in Fig.14 In the example, unit 1406 is based on the AGC symbol 1402 pre-appended to unit 1404. Fig.14 The number, arrangement or other aspects of the DMRS and PSSCH shown in . For example, units other than three (as shown in 1404) may be used.

[0177] In some embodiments, an S-TTI pattern with reserved / excluded symbol construction may be used. In a non-limiting example, an S-TTI pattern of size m with k excluded / reserved symbols may be constructed from L basic S-TTI patterns according to a relationship in which the sum of k and the pattern sizes of the L basic S-TTI patterns equals m. For example, the following relationship or a similar relationship may be used.

[0178]

[0179] In some embodiments, an LTE frame structure with a side link S-TTI can be used. Based on a set of S-TTI structures and processes constructed based on the S-TTI mode, the following two types of LTE side link frame structures can be constructed. In a non-limiting example, the subframe structure can be aligned with a traditional (including but not limited to LTE R14) side link subframe structure. The S-TTI design that generates the subframe structure can be aligned with the traditional subframe. In some cases, this can be used to achieve the benefits of traditional SCI-F1 use. In this case, traditional UE 102 can use traditional processes to perform AGC establishment and PSSCH-RSRP measurement.

[0180] In another non-limiting example, a different frame structure with a specific subframe structure may be used. In some embodiments, the subframe structure may be different from a legacy (such as LTE R14 and / or other) subframe structure. Although the S-TTI structure may be optimized for enhanced UE 102 reception and / or R15 UE 102 reception, in some cases, legacy UE 102 performance may be degraded due to inappropriate PSSCH-RSRP and S-RSSI measurements.

[0181] In some embodiments, the S-TTI subframe structure may be aligned with a legacy (such as LTE R14 and / or other) PSSCH / PSCCH subframe structure. In some embodiments, the legacy DMRS structure may include four DMRS per subframe. Assuming that the DMRS location and waveform are not changed (to reduce the impact on legacy sensing and resource selection processes), in some cases, the S-TT1 configuration options may be limited. In some embodiments, the S-TTI may have one or two DMRS symbols, resulting in a slot-based S-TTI and a subslot-based S-TTI physical structure.

[0182] In some embodiments, in conventional operation, the last symbol of the sidelink subframe (such as the final symbol) may be punctured. In some embodiments, for S-TTI-based operation, the above puncturing may not be necessary. In addition, in some cases of S-TTI, the last symbol of the subframe may be used for S-TTI transmission. In some cases, it may be assumed that there is enough time to perform AGC and TX / RX turnaround within one symbol. Otherwise, reception of subsequent S-TTIs may be skipped.

[0183] In some embodiments, a slot- and sub-slot-based S-TTI structure may be used. In the case of a slot-level TTI, two DMRS may exist per S-TTI spanning a slot. In the case of a sub-slot-level TTI, one DMRS may be used per S-TTI. The amount of symbols per S-TTI may depend on one or more assumptions of the AGC operation of the enhanced UE 102 and / or R15 UE 102. In a non-limiting example, a symbol for establishing AGC within the S-TTI may be used. In another non-limiting example, a dedicated AGC symbol may be used at the first symbol of a subframe. In some cases, this may be considered as "fast AGC", although the scope of the embodiments is not limited in this respect.

[0184] Non-limiting example subframe configurations are Figure 14-17 These examples are not exhaustive. In some embodiments, the structure can be based on Figure 14-17 In some embodiments, the structure may be similar to Figure 14-17One or more structures shown in . Embodiments are not limited to the number, type, arrangement and / or other aspects of the symbols shown.

[0185] In some embodiments, the GAP symbols may be occupied by an S-TTI with an increased number of symbols, or may be allocated for a one symbol S-TTI that may be used for transmission of a fast response or acknowledgment.

[0186] In some embodiments, the structure may be aligned with a legacy structure. For example, the structure may be aligned with a legacy LTE (including but not limited to LTE R14) sidelink PSSCH / PSCCH subframe structure. Fig.14 and 15 14. Structure 1410 is based on subframe granularity and further based on AGC within a symbol duration. Structure 1420 is based on subframe granularity and further based on AGC within a normal cyclic prefix (CP). Structure 1430 is based on subframe granularity and further based on AGC at the first symbol of a subframe. The structure includes AGC symbol 1432.

[0187] Structure 1510 is based on slot granularity (including but not limited to 6 or 7 symbols) and further based on AGC within one symbol duration. Structure 1520 is based on slot granularity and further based on AGC within a normal cyclic prefix (CP). Structure 1530 is based on slot granularity and further based on AGC at the first symbol of a subframe. The structure includes AGC symbol 1532.

[0188] Structure 1540 is based on sub-slot granularity (including but not limited to 3 or 4 symbols) and further based on AGC within one symbol duration. Structure 1550 is based on sub-slot granularity and further based on AGC within a normal cyclic prefix (CP). Structure 1560 is based on sub-slot granularity and further based on AGC at the first symbol of a subframe. The structure includes AGC symbol 1562.

[0189] In some embodiments, including but not limited to cases with arbitrary frame structures, the S-TTI boundaries may not necessarily align with the traditional LTE subframe boundaries.

[0190] In some embodiments, the S-TTI may be aligned with a conventional LTE subframe boundary. A subframe may include an integer number of S-TTIs. Depending on the subframe design and the AGC setup time assumption, a subframe may include one or more of the following: one or more S-TTIs with a dedicated AGC setup time within each S-TTI; one or more S-TTIs without a dedicated AGC setup time interval; shared AGC setup time interval and S-TTI without a dedicated AGC setup time; and / or other. In addition, a subframe may also include one or more reserved symbols. For example, such reserved symbols may be used for TX RX switching, additional reference signal transmission, and / or other.

[0191] A non-limiting example of a subframe structure construction for a subframe with a normal cyclic prefix type is shown in Fig.16 A similar structure can also be constructed for subframes with an extended cyclic prefix. In some cases, Fig.16 The example structures in can be constructed without the retention of the traditional subframe structure. Structure 1610 is determined according to the slot granularity (including but not limited to 6 or 7 symbols) and further according to the AGC establishment within one symbol duration. Structure 1620 is determined according to the slot granularity and further according to the AGC establishment within the CP. Structure 1630 is determined according to the slot granularity and further according to the AGC establishment at the first symbol of the subframe. The structure includes AGC symbol 1632. Structure 1640 is determined according to the sub-slot granularity (including but not limited to 3, 4 or 5 symbols) and further according to the AGC establishment within one symbol duration. Structure 1650 is determined according to the slot granularity and further according to the AGC establishment within the CP. Structure 1660 is determined according to the sub-slot granularity and further according to the AGC establishment at the first symbol of the subframe. The structure includes AGC symbol 1662.

[0192] In some embodiments, an S-TTI design without traditional subframe boundary alignment may be used. In some embodiments, S-TTIs may follow one after another without aligning with traditional subframe boundaries. Similar to other cases described herein, each S-TTI may include a dedicated AGC symbol. Otherwise, the shared AGC symbol may be repeated with a predefined period. Fig.17 An example of a continuous S-TTI design for three different TTI sizes and three different frame structures designed for different AGC operation modes is shown in . The structure 1710 is based on a granularity of a unit including multiple symbols and is further established based on AGC within one symbol duration. Fig.17The example in shows a structure based on a slot granularity of three symbols, but any suitable number of symbols may be used. Structure 1720 is based on a granularity of a unit including three symbols, and is further established based on AGC within a CP. Structure 1730 is based on a granularity of a unit including three symbols, and is further established based on AGC at the first symbol of a subframe. The structure includes AGC symbol 1732.

[0193] In some embodiments, the S-TTI structure can be used to broadcast data. In some cases, when fast confirmation or response is required, multicast and unicast transmissions may also have some advantages. In some cases, traditional SCI-F1 transmissions can be used to reserve resources for S-TTI transmissions (including but not limited to fast response). It should be noted that similar mechanisms can be enabled using S-TTI control signaling, but may be incompatible with traditional UE 102 and may require a finer time scale for resource selection.

[0194] For example, in the case of two TTI transmissions, a UE 102 supporting S-TTI Tx / Rx may use the first TTI for transmission and may follow conventional procedures (e.g., use of conventional PSCCH and PSSCH). The UE 102 may reserve the second TTI and may use it for reception to collect responses from a group of vehicles in the S-TTI transmission format. Alternatively, the UE 102 may use conventional PSCCH transmissions in conjunction with sPSCCH and sPSSCH to reserve resources for fast unicast responses from a group of UEs 102. The examples 1800, 1850 shown in FIG. 18 illustrate this concept.

[0195] In some embodiments, the sPSCCH channel may be used to send resource allocation grants for sPSSCH transmissions. Fig.19 Example 1900 in illustrates this concept.

[0196] In some embodiments, a method for sidelink communication for V2V (vehicle-to-vehicle) communication may include one or more of the following: configuration of a sidelink short transmission time interval (S-TTI) for communication; configuration of a physical sidelink control channel (sPSCCH) and an S-TTI physical sidelink shared channel (sPSSCH) based on S-TTI; configuration of FDM / TDM multiplexing for sPSCCH and sPSSCH transmission; sidelink communication using S-TTI and L-Τ transmission formats within the same set of resources (resource pool); sidelink communication using S-TTI transmission format on a dedicated resource set; measurement of S-RSSI and PSCCH / PSSCH RSRP based on an S-TTI physical structure; sensing and resource selection for transmission of sidelink shared and control channels based on S-TTI or L-TTI resource allocation; transmission of two SCI formats, one for legacy (such as LTE R14) terminals and the other for enhanced (such as R15) terminals; transmission of SCI to reserve S-TTI resources for transmission by other UEs 102; and / or others.

[0197] In some embodiments, the sidelink S-TTI may contain 1, 2, 3, 4, 5, 6, or 7 symbols including DMRS, and a sidelink control or shared channel transmission. The DMRS signal allocation within the S-TTI may be predefined according to one of the basic modes. In some embodiments, the sPSCCH and / or sPSSCH physical structure may be defined based on the S-TTI structure and sent within the subframe duration.

[0198] In some embodiments, sidelink communications may use S-TTI and L-TTI transmission formats of PSCCH and PSSCH within the same set of resources (resource pool). In some embodiments, one or more UEs 102 may communicate using the L-TTI transmission format (PSCCH / PSSCH). In some embodiments, one or more UEs 102 may communicate using the S-TTI transmission format (sPSCCH / sPSSCH). In some embodiments, one or more UEs 102 may use S-TTI to send two SCI formats, one for legacy UEs 102 (PSSCH) and the other for enhanced UEs 102 (PSCCH or sPSCCH). In some cases, this may enable seamless coexistence within the same set of resources. In some embodiments, one or more UEs 102 may use S-TTI to send one or more AGC training symbols at the beginning of each subframe to enable adjustment of the AGC for legacy UEs 102. The AGC training symbol may be a dedicated AGC signal, DMRS, data symbol, and / or other. In some embodiments, one or more UEs 102 supporting S-TTI may use fast AGC operation by adjusting the AGC at the occurrence of each S-TTI within the cyclic prefix duration.

[0199] In some embodiments, S-TTI transmissions may be allowed on dedicated resources including a sPSCCH / sPSSCH resource pool or an S-TTT component carrier. In some embodiments, S-RSSI, PSCCH / PSSCH RSRP measurements may be defined for the S-TTI structure or configured time granularity. In some embodiments, the S-RSSI, PSCCH / PSSCH RSRP measurements defined for the S-TTI structure may be used for S-TTI resource selection with finer time granularity. In some embodiments, UE 102 may select resources for transmission by other UEs 102. In some embodiments, UE 102 may use the SCI format for legacy UE 102 and / or enhanced UE 102 to notify other UEs 102 of the S-TTI resources reserved for their transmissions.

[0200] In some embodiments, the S-TTI may include one or more of the following: a PSCCH signal, a PSSCH signal, an AGC training signal, one or more DMRS and / or other. In some embodiments, the S-TTI structure may be based on one or more basic modes. In some embodiments, one or more S-TTIs may follow continuously in time. In some embodiments, an LTE subframe may include an integer number of S-TTIs. In some embodiments, multiple LTE subframes may include the same number of S-TTIs. In some embodiments, the DMRS sent in the S-TTI may be the same as the symbol in the LTE subframe.

[0201] In some embodiments, including but not limited to embodiments including operations according to the 3GPP LTE Release 14 (LTE R14) specification, vehicle-to-vehicle (V2V) communications may be supported. In some cases, a cycle greater than 100 milliseconds may be used. In some cases, a waiting time of 100 milliseconds or less may be used. In some embodiments, a reduced waiting time (such as 20 milliseconds or other values) may be used. This reduced waiting time may provide challenges in some use cases, including but not limited to use cases based on short transmission cycles and low waiting time requirements. Therefore, in some cases, it may be beneficial to enable LTE V2V communications to reduce waiting time technologies. In some embodiments, a vehicle-to-everything (V2X) system may operate according to a waiting time far less than 100 milliseconds.

[0202] In some embodiments, techniques may be used to support communications with relatively short packet generation cycles and / or relatively low latency. In some embodiments, enhancements may be applied to conventional (including but not limited to LTE R14) V2V sensing and resource selection processes to support transmissions with reduced latency. For example, in some cases, enhancements to sensing windows and resource selection windows and new UE 102 behaviors may reduce latency for LTE V2V communications.

[0203] In some embodiments, including but not limited to embodiments including operations according to conventional LTE and / or LTE R14, UE 102 may determine a set of resources for PSCCH / PSSCH transmission when requested by a higher layer in subframe n. UE 102 may assume that any resource within the time interval [n+T1, n+T2] corresponds to a candidate single subframe resource. In some cases, the selection of T1 and T2 may be achieved by UE 102 under the constraints of T1≤4 and 20≤T2≤100. UE 102's selection of T2 may also achieve a target waiting time. For resource selection, UE 102 may monitor subframes [n-1000, n-999, ..., n-1] in addition to those subframes in which its transmission occurs. UE 102 may perform a resource selection process based on PSCCH decoding and / or RSRP, S-RSSI measurements in these subframes. Fig. 20 A non-limiting example of LTE legacy V2V resource selection is shown in FIG.

[0204] In some embodiments, including but not limited to embodiments including operation according to conventional LTE and / or LTE R14, the maximum time between the arrival of a packet at LI and the resource selected for transmission may be determined by the value of T2, which may vary from T2min=20 to T2max=100 and may be subject to latency constraints. In some cases, based on a conventional subframe duration of 1 millisecond, this method may achieve a 20 millisecond latency and transmission period for V2 communications.

[0205] To further reduce the maximum time between packet arrival at LI and selection of resources for transmission, the minimum and maximum values ​​of T2 may be further reduced. In a non-limiting example, one or more of the following may be used: T2min=T1; T2max=10 milliseconds; 4≤T1≤T2≤10.

[0206] In a non-limiting example, in some use cases, the waiting time can vary from 3 milliseconds to 100 milliseconds, and a specific T2 value can be configured by a higher layer. In another non-limiting example, in some use cases, the waiting time can vary from 10 milliseconds to 20 milliseconds. In some cases, if multiple UEs 102 operate with low waiting times, including but not limited to waiting times of 20 milliseconds or lower, the waiting time for resource selection less than 20 milliseconds may reduce the probability of causing a conflict to increase. This may be due to one or more factors, such as lack of resources in the selection window, half-duplex problems and / or other factors. In some cases, if a waiting time such as 20 milliseconds, 10 milliseconds or similar is expected, it may not necessarily be beneficial to mix such transmission with a transmission utilizing a transmission interval greater than 100 milliseconds.

[0207] In some embodiments, a limit on the resource reservation interval per pool configuration may be used. However, in some cases, a one-second sensing window may be used. This window size may be independent of the pool configuration, and the UE 102 may be expected to hold the selected resource for at least half a second in time, and thus may be conflicted until the next resource reselection. Therefore, one or more techniques may be applied to further reduce the waiting time and / or resource reservation period.

[0208] In a non-limiting example technique that can be applied to further reduce latency and / or resource reservation periods, a pool-specific reference reservation period can be used. For each resource pool, a reference reservation period can be signaled. In some cases, this value can represent a typical expected generation period of packets sent in such a pool. In this case, the reference reservation period value, the transmission time interval value (T TTI ) and / or others to determine parameters for sensing, resource selection, and congestion control.

[0209] In a non-limiting example, the conventional LTE reference resource reservation period may be P Basic =100, and T TTI = SubframeDuration = value of 1 msec. In this case, the main sensing, resource selection and congestion control parameters can be derived as follows: Sensing window duration: T SensWindow =10*P reference ; Resource selection window T 2max =P reference ; Resource reselection counter range: Counter Resel =[500, 600, ..., 1500] / P Tx,for PTx<P Reference ; Maximum number of other UEs reserved within the Rx UE resource (re)selection window: N resv =P reference / P Tx , P Tx <P Reference ;P step_nonTDD =P Reference ; Other Pstep values ​​(which may be determined taking into account DL / UL configuration); Congestion control channel busy ratio measurement duration: T CBR =P Reference ; and / or others. Fig.21 The non-limiting example in shows LTE sensing and resource selection parameters derived from a reference resource reservation period value.

[0210] In another non-limiting example technique that may be applied to further reduce latency and / or resource reservation periods, a pool limited to a small period (e.g., limited to low latency transmissions) may be used. This may be accomplished by extending the list of valid values ​​allowed by the LTE R14 parameter "restrictResourceReservationPeriocF" assignment and adding lower values ​​to this field. However, embodiments are not limited to use of this parameter, as other parameters and / or messages may be used in some embodiments.

[0211] In another non-limiting example technique that can be applied to further reduce latency and / or resource reservation period, a reduced sensing window can be used. In conventional systems (including but not limited to LTE R14), a one-second sensing window can be used independently of the periodicity and resource reservation interval used for transmission. For some cases where only low latency transmissions (small resource reservation period) are configured per resource pool, the sensing window duration can be shortened.

[0212] In another non-limiting example technique that may be applied to further reduce the waiting time and / or resource reservation period, a reduced resource (re)selection time may be used. The resource (re)selection time may be reduced by reducing the number of TBs sent before resource reselection. For example, if a small resource reservation period is configured per pool, the time may be reduced from [25, 75] 20 milliseconds to [5 15] milliseconds in LTE R14. The resource reselection counter value may be configurable per pool.

[0213] In another non-limiting example technique that can be applied to further reduce the waiting time and / or resource reservation period, a reduced resource (re)selection window can be used. In some cases, the resource (re)selection window can be limited to a minimum T2 value equal to 20. If the value of T2 is further reduced, the waiting time can be reduced accordingly. Therefore, in some embodiments, a value such as 5 or 10 can be used as a preconfigured value, or the T2 value can be configured by a higher layer within predefined boundaries.

[0214] In another non-limiting example technique that can be applied to further reduce waiting time and / or resource reservation period, multiple transmission processes can be used. Multiple transmission processes utilizing resource selection windows that shift in time can be used to reduce total transmission waiting time. In some cases, this method can reduce the waiting time in an average statistical sense. In some cases, this method can be used in combination with other principles to meet strict waiting time targets.

[0215] In another non-limiting example technique that can be applied to further reduce latency and / or resource reservation periods, a "first in time" candidate resource selection can be used. In some embodiments, including but not limited to embodiments including those based on the use of LTER14 and / or other conventional protocols, resources for transmission can be randomly selected from a set of candidate resources within a resource selection window. Instead of using random resource selection, the first resource in time can be selected from a set of candidate resources, and thereby reducing latency in an average sense.

[0216] In another non-limiting example technique that may be applied to further reduce latency and / or resource reservation period, a number of remaining transmissions may be signaled. The UE 102 may use this information to perform resource reselection to predict resource occupancy and select resources appropriately. Non-limiting examples of LTE sensing and resource selection parameters derived from the basic resource reservation period value are described in Fig. 22 . If other UEs 102 are notified within the reselection window that the resource will be released, the UE 102 may be allowed to select a resource currently occupied by another UE 102. If the probabilistic resource reselection mechanism is enabled, the UE 102 sending data may pre-check whether resource reselection occurs and may signal an appropriate value. To minimize signaling overhead, if the number of remaining transmissions exceeds a predetermined threshold, a maximum value may be signaled. This technique may not necessarily affect latency, but may improve overall sensing and resource selection performance in some cases.

[0217] In another non-limiting example technique that can be applied to further reduce latency and / or resource reservation periods, multiple reserved transmissions can be signaled. This information and / or the number of remaining transmissions can be used to determine one or more of: when to start resource reservation; when resource reservation is expected to end. If the UE 102 has a resource to reselect, this information can be useful to compensate for the estimate of received power at a particular resource. If the receiver knows that the transmitter has released the resource, the power received from the particular signal source can be subtracted from the total received power.

[0218] In another non-limiting example technique that can be applied to further reduce waiting time and / or resource reservation period, short reservation period signaling in SCI can be used. The resource reservation period can be signaled in SCI using the "resource reservation" field. In some embodiments, other techniques for resource reservation signaling in SCI can be used. In a non-limiting example of a technique for resource reservation signaling in SCI, a list of reservation periods can be extended. A new reservation period can be included in the list of supported reservation periods. In this case, enhanced UE 102 may be able to correctly decode this field in SCI. Traditional UE 102 may not be able to correctly detect the resource reservation period, which may have a negative impact on its resource selection decision. Therefore, the coexistence of R14 and R15 UEs in the same resource pool may be problematic.

[0219] In another non-limiting example of a technique for resource reservation signaling in SCI, a field for scaling a configured resource reservation value may be used. A "ResvPeriodScale" field (which may be referred to below as "M" for clarity) or the like may be used with a signaled multiplier together with a signaled traditional resource reservation period to obtain an actual resource reservation period. The reservation period and the scaling factor may be selected according to different values ​​of the parameter M. Two non-limiting examples of M are given below. In the first example, M may be an arbitrary value. In this case, the enhanced UE 102 may correctly determine the resource reservation period. However, the traditional UE 102 may use erroneous information about resource reservation, which may degrade its resource selection performance. In the second example, M may be based on 1 / N, where N may be a reduction factor represented by an integer value. In some cases, coexistence of enhanced UE PSCCH signaling with traditional UE 102 receiving behavior may be achieved. Traditional UE 102 may interpret a transmission from a single enhanced UE 102 with a short period transmission as N different transmissions from different UEs 102, and may take them into account during sensing and resource selection.

[0220] A non-limiting example of mini-cycle resource signaling compatible with conventional UE sensing and resource selection procedures is Fig.23 As shown in Fig.23 As shown in FIG. 2 , two SCI processes 2320 are used to send a signal with a short transmission period P. Tx 2315, each SCI process 2320 has a signaled legacy retention period P RSVP , 2342, but the actual transmission cycle is twice less.

[0221] In some embodiments, in addition to the resource reselection process based on the long sensing window processing, short-term sensing at the beginning of each subframe (e.g., the first symbol of the subframe) can be used. If the short-term sensing result indicates that the received power in the entire symbol or a specific subchannel of the first symbol is lower than the threshold and / or the received power estimate of the selected candidate resource, the UE 102 can be allowed to transmit in the specific subframe.

[0222] In some embodiments, the congestion control mechanism can be based on one or more metrics, including but not limited to those described below. In the first example metric, a channel busy ratio (CBR) measured in subframe n can be defined for PSSCH, PSCCH and / or other. For PSSCH, the subchannel portion of the S-RSSI measured by UE 102 in the resource pool exceeds the threshold sensed on the subframe range. Non-limiting example ranges include subframes [n-100, n-1]. Ranges of other sizes can be used. For PSCCH, in a pool configured so that PSCCH can be sent together with the corresponding PSSCH in non-adjacent resource blocks, the resource portion of the PSCCH pool in which the S-RSSI measured by the UE exceeds the threshold sensed on the subframe range can be used. Non-limiting example ranges include subframes [n-100, n-1]. Ranges of other sizes can be used. In some cases, it can be assumed that the PSCCH pool includes resources with a size of two consecutive PRB pairs in the frequency domain.

[0223] In a second example metric, the channel occupancy rate (CR) evaluated at subframe n can be defined as the total number of subchannels configured in the transmission pool within [na, n+b] divided by the total number of subchannels used for their transmission in subframe [na, n-1] and permitted in subframe [n, n+b]. In some embodiments, parameter a can be a positive integer and b can be a non-negative integer. In a non-limiting example, a and b can be determined by the UE implementation, where a+b+1=1000, a>=500. In addition, b can be selected so that in some embodiments, (n+b) does not exceed the last transmission opportunity granted for the current transmission.

[0224] In some embodiments, the congestion control design may be based on the management of traffic with 100 ms latency and packet generation period ≥ 100 ms.In a non-limiting example, the CBR measurement duration may be selected to be 100 ms and the CR estimation interval may be equal to one second.

[0225] In some embodiments, if the packet transmission period is significantly shorter than 100 milliseconds, then the relevant CBR measurement performed before each transmission can be observed. To overcome this problem, a reduced CBR measurement duration for short-period communications can be used. For example, for a 20 millisecond packet generation period, T CBR=20 ms or less (e.g. 10 ms).

[0226] In some embodiments, if short-period transmissions are configured in the resource pool, a duration of one second may be too long for CR estimation. For that case, the CR estimation duration may also be proportionally reduced in some cases.

[0227] In some embodiments, a method for sidelink vehicle-to-vehicle (V2V) communication may be performed. In some cases, low latency and short transmission cycles may be used and / or implemented, but the scope of the embodiments is not limited in this regard. The method may include one or more of the following: configuration of a resource pool sensing window, a resource selection window, and congestion measurement parameters; UE 102 selects resources for low latency / short cycle transmissions with multiple resource selection windows; UE 102 signals one or more resource reservation parameters in the SCI. In some embodiments, a reference resource reservation period may be configured per pool representing a primary transmission period. In some embodiments, resource selection, sensing, and congestion control parameters may be derived from the configured reference resource reservation period. In some embodiments, the pool may be configured with restrictions on the UE 102 resource reservation period. For example, values ​​of 20, 10, and / or 5 milliseconds may be used.

[0228] In some embodiments, the sensing window duration may be configured per resource pool. In some embodiments, the sensing window duration may depend on the allowed resource reservation period (or reference resource reservation period). In some embodiments, the sensing window duration may be less than a one-second duration. In some embodiments, the minimum duration of the resource selection window measured from the resource reselection trigger may be less than 20 milliseconds (e.g., 5 or 10 milliseconds or lower and / or a value configured by a higher layer).

[0229] In some embodiments, multiple "time-shifted" resource selection windows can be configured. In some embodiments, the maximum time shift between resource selection windows may not be greater than the packet generation period divided by a number. In some embodiments, resources from a resource selection window may be selected with a higher priority, and the resource selection window has a smaller time distance measured from a resource reselection trigger instance. In some embodiments, a first time resource may be selected for transmission between candidate resource sets. In some embodiments, multiple remaining reserved transmissions may be signaled within the SCI for a given resource reservation process. In some embodiments, the total number of reserved transmissions may be signaled within the SCI. In some embodiments, a short retention period may be signaled within the SCI.

[0230] In some embodiments, signaling may be implemented using a resource reservation value signaled within the SCI. In some embodiments, signaling may be implemented in a backward compatible manner, where an additional field in the SCI indicates the size of a reservation period applied to legacy (including but not limited to LTE R14). The additional field may be used to calculate the actual reservation period in order to make it compatible with legacy sensing and resource selection behavior.

[0231] In some embodiments, the scaling factor signaled in the SCI may be an arbitrary value. In some embodiments, the scaling factor signaled in the SCI may represent a number for a quotient (such as of the form 1 / N).

[0232] In some embodiments, the reduced channel busy ratio measurement duration can be configured per pool. In some embodiments, the channel busy ratio measurement duration can be less than 100 milliseconds. In some embodiments, the reduced (such as less than one second or other value) channel occupancy estimation interval can be configured per pool, or derived from the actual sensing window duration. In some embodiments, the channel occupancy estimation interval can be less than one second. In some embodiments, the channel occupancy estimation interval can be derived from the sensing window duration.

[0233] In Example 1, a device of a user equipment (UE) may include a memory. The device may further include a processing circuit. The processing circuit may be configured to select a short TTI for a vehicle-to-vehicle (V2V) side link transmission of the UE from a plurality of short transmission time intervals (TTIs). The short TTI may occur within a traditional TTI. The short TTI may be allocated for V2V side link transmissions performed by non-traditional UEs, and the traditional TTI may be allocated for V2V side link transmissions performed by traditional UEs. The processing circuit may be further configured to encode a traditional physical side link control channel (PSCCH) for transmissions according to traditional Τ to indicate the V2V side link transmission of the UE to the traditional UE. The processing circuit may be further configured to encode a short PSCCH (sPSCCH) for transmissions according to the selected short TTI to indicate the transmission of the V2V side link of the UE to the non-traditional UE. The memory may be configured to store information identifying the selected short TTI.

[0234] In Example 2, the subject matter of Example 1, wherein the processing circuit can be further configured to encode a short physical sidelink shared channel (sPSSCH) based on a data bit block for a V2V sidelink transmission of the UE. The sPSSCH can be encoded for transmissions according to a selected short TTI. The sPSSCH and sPSCCH can be encoded for transmissions in separate frequency resources according to a frequency division multiplexing (FDM) technique.

[0235] In Example 3, the subject matter of one or any combination of Examples 1-2, wherein the processing circuit can be further configured to encode a short physical sidelink shared channel (sPSSCH) based on a data bit block for a V2V sidelink transmission of the UE. For transmissions according to a time division multiplexing (TDM) technique, the sPSSCH is encoded in a short TTI that occurs after a selected short TTI.

[0236] In Example 4, the subject matter of one or any combination of Examples 1-3, wherein the processing circuitry may be further configured to encode a legacy PSCCH for transmissions in a first frequency resource allocated by a legacy UE for V2V sidelink transmissions. The processing circuitry may be further configured to encode an sPSCCH for transmissions in a second frequency resource allocated by a non-legacy UE for V2V sidelink transmissions.

[0237] In Example 5, the subject matter of one or any combination of Examples 1-4, wherein the processing circuit is further configured to determine one or more sensing or signal quality measurements for the plurality of short TTIs based on one or more channel sensing operations prior to the traditional TTI. The processing circuit may be further configured to select the short TTI for the UE's V2V sidelink transmission based at least in part on the sensing or signal quality measurements.

[0238] In Example 6, the subject matter of one or any combination of Examples 1-5, wherein the legacy TTI may span one millisecond (msec). The plurality of short TTIs may include four short TTIs.

[0239] In Example 7, the subject matter of one or any combination of Examples 1-6, wherein the selected short TTI may span multiple symbol periods. At least one of the symbol periods may be based on a demodulation reference signal (DMRS). At least one of the symbol periods may be based on data bits.

[0240] In Example 8, the subject matter of one or any combination of Examples 1-7, wherein the processing circuitry may be further configured to, for transmissions in a first time sequential symbol period of a legacy TTI, encode an automatic gain control (AGC) element to enable AGC at a legacy UE in a shared AGC symbol.

[0241] In Example 9, the subject matter of one or any combination of Examples 1-8, wherein the processing circuit may be further configured to encode the AGC element for a transmission in a first time sequential symbol period of a legacy TTI regardless of a position of the selected TTI within the legacy TTI.

[0242] In Example 10, the subject matter of one or any combination of Examples 1-9, wherein the sPSCCH may include sidelink control information (SCI) indicating first information related to the V2V sidelink transmission of the UE. The legacy PSCCH may include sidelink control information (SCI) format-1 (SCI-F1) indicating second information related to the V2V sidelink transmission of the UE.

[0243] In Example 11, the subject matter of one or any combination of Examples 1-10, wherein the processing circuit may be further configured to set the duration of the resource selection window according to a latency criterion, wherein the latency criterion is less than or equal to 20 milliseconds.

[0244] In Example 12, the subject matter of one or any combination of Examples 1-11, wherein the apparatus may further include a transceiver for transmitting a legacy PSCCH and an sPSCCH.

[0245] In Example 13, the subject matter of one or any combination of Examples 1-12, wherein the processing circuitry may include a baseband processor for selecting the short TTI.

[0246] In Example 14, a computer-readable storage medium may store instructions for execution by one or more processors to perform operations for communicating by a user equipment (UE). The operations may configure one or more processors to select a resource pool for vehicle-to-vehicle (V2V) side link transmission of the UE from a candidate resource pool. The subframes of different candidate resource pools may be non-overlapping. The candidate resource pools may be allocated for V2V transmissions of different waiting times per candidate resource pool. The operations may further configure one or more processors to attempt to detect V2V side link transmissions of other UEs during a sensing window before the selected resource pool. The operations may further configure one or more processors to determine one or more candidate subframes of a resource selection window that can be used by the UE for V2V side link transmission based on side link control information (SCI) included in the V2V side link transmission detected in the sensing window. The resource selection window may be after the sensing window.

[0247] In Example 15, the subject matter of Example 14, wherein the operation may further configure the one or more processors to select one or more subframes for V2V sidelink transmission by the UE in the resource selection window from the candidate subframes. The operation may further configure the one or more processors to encode a physical sidelink shared channel (PSSCH) based on the data bit block for transmission in the selected subframe.

[0248] In Example 16, the subject matter of one or any combination of Examples 14-15, wherein the operations may further configure the one or more processors to select one or more subframes for V2V sidelink transmission by the UE in a plurality of resource selection windows shifted in time.

[0249] In Example 17, the subject matter of one or any combination of Examples 14-16, wherein the operations may further configure the one or more processors to select the one or more subframes to include the earliest candidate subframe in the resource selection window.

[0250] In Example 18, the subject matter of one or any combination of Examples 14-17, wherein the candidate resource pool may be configured to sense windows of different durations. The duration may be based at least in part on a reservation period of the candidate resource pool.

[0251] In Example 19, the subject matter of one or any combination of Examples 14-18, wherein the operation may further configure the one or more processors to determine one or more signal qualities or sensing measurements during the sensing window. The operation may further configure the one or more processors to determine the candidate subframe based at least in part on the signal qualities or sensing measurements.

[0252] In Example 20, the subject matter of one or any combination of Examples 14-19, wherein the resource pool may include a plurality of subchannels per subframe. The signal quality or sensing measurement may include a channel busy ratio (CBR) based at least in part on a ratio of subchannels during the subframe window as follows: a total number of subchannels having a signal quality measurement above a threshold, and a ratio of the total number of subchannels.

[0253] In Example 21, the subject matter of one or any combination of Examples 14-20, wherein the operation may further configure one or more processors to select a resource pool from the candidate resource pools based at least in part on: a target waiting time for the UE's V2V sidelink transmission, and a different waiting time for each candidate resource pool.

[0254] In Example 22, the subject matter of one or any combination of Examples 14-21, wherein the resource selection window can span a range of: a first configurable value between 0 and 4 milliseconds (msec), and a second configurable value between the first configurable value and 20 msec.

[0255] In Example 23, a device of a user equipment (UE) may include a memory. The device may further include a processing circuit. The processing circuit may be configured to select a short TTI for a vehicle-to-vehicle (V2V) sidelink transmission performed by the UE from a plurality of short transmission time intervals (TTIs). A traditional TTI may be divided into short TTIs. The processing circuit may be further configured to encode a short physical sidelink control channel (sPSCCH) for indicating the V2V sidelink transmission of the UE for transmissions according to the selected short TTI. The processing circuit may be further configured to encode a short physical sidelink shared channel (sPSCCH) based on a data bit block for transmissions according to the selected short TTI. The processing circuit may be further configured to encode an automatic gain control (AGC) element to enable AGC at a traditional UE or a non-traditional UE for transmissions in the first time sequential symbol period of the traditional TTI. The memory may be configured to store information identifying a short TTI.

[0256] In Example 24, the subject matter of Example 23, wherein short TTIs may be allocated for V2V sidelink transmissions for non-legacy UEs. Legacy TTIs may be allocated for V2V sidelink transmissions for legacy UEs.

[0257] In Example 25, the subject matter of one or any combination of Examples 23-24, wherein the legacy TTI may span one millisecond (msec). The plurality of short TTIs may include four short TTIs.

[0258] In Example 26, the subject matter of one or any combination of Examples 23-25, wherein the selected short TTI may span multiple symbol periods. At least one of the symbol periods may be based on a demodulation reference signal (DMRS). At least one of the symbol periods may be based on a block of data bits.

[0259] In Example 27, the subject matter of one or any combination of Examples 23-26, wherein the processing circuit may be further configured to encode the AGC element for a transmission in a first time sequential symbol period of a legacy TTI regardless of a position of the selected TTI within the legacy TTI.

[0260] In Example 28, an apparatus of a user equipment (UE) may include a module for selecting a resource pool for vehicle-to-vehicle (V2V) sidelink transmission of the UE from a candidate resource pool. Subframes of different candidate resource pools may be non-overlapping. The candidate resource pools may be allocated V2V transmissions of different waiting times per candidate resource pool. The apparatus may further include a module for attempting to detect V2V sidelink transmissions of other UEs during a sensing window before the selected resource pool. The apparatus may further include a module for determining one or more candidate subframes of a resource selection window that the UE can use for V2V sidelink transmission based on sidelink control information (SCI) included in the V2V sidelink transmission detected in the sensing window. The resource selection window may be after the sensing window.

[0261] In Example 29, the subject matter of Example 28, wherein the apparatus may further include means for selecting one or more subframes for V2V sidelink transmissions by the UE from candidate subframes in a resource selection window. The apparatus may further include means for encoding a physical sidelink shared channel (PSSCH) based on a data bit block for transmissions in the selected subframes.

[0262] In Example 30, the subject matter of one or any combination of Examples 28-29, wherein the apparatus may further include means for selecting one or more subframes for V2V sidelink transmission by the UE in a plurality of resource selection windows shifted in time.

[0263] In Example 31, the subject matter of one or any combination of Examples 28-30, wherein the apparatus may further comprise means for selecting one or more subframes comprising the earliest candidate subframe in the resource selection window.

[0264] In Example 32, the subject matter of one or any combination of Examples 28-31, wherein the candidate resource pool may be configured to sense windows of different durations. The duration may be based at least in part on a reservation period of the candidate resource pool.

[0265] In Example 33, the subject matter of one or any combination of Examples 28-32, wherein the apparatus may further include means for determining one or more signal qualities or sensing measurements during the sensing window. The apparatus may further include means for determining a candidate subframe based at least in part on the signal qualities or sensing measurements.

[0266] In Example 34, the subject matter of one or any combination of Examples 28-33, wherein the resource pool may include a plurality of subchannels per subframe. The signal quality or sensing measurement may include a channel busy ratio (CBR) based at least in part on a ratio of subchannels during the subframe window as follows: a total number of subchannels having a signal quality measurement above a threshold, and a ratio of the total number of subchannels.

[0267] In Example 35, the subject matter of one or any combination of Examples 28-34, wherein the apparatus may further include a module for selecting a resource pool from the candidate resource pools based at least in part on: a target waiting time for the UE's V2V sidelink transmission, and a different waiting time for each candidate resource pool.

[0268] In Example 36, the subject matter of one or any combination of Examples 28-35, wherein the resource selection window can span a range of: a first configurable value between 0 and 4 milliseconds (msec), and a second configurable value between the first configurable value and 20 msec.

[0269] The Abstract is provided to comply with 37 CFR Section 1.72(b), which requires that the Abstract enable the reader to ascertain the nature and gist of the technical disclosure. It is submitted with the understanding that it will not be used to limit or interpret the scope or meaning of the claims. The following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment.

Claims

1. A method for transmitting a side link transmission, comprising: User equipment UE (102), selecting a sidelink resource for a sidelink transmission; as well as The sidelink transmission is transmitted on the selected sidelink resource, wherein the sidelink transmission includes an initial orthogonal frequency division multiplexing (OFDM) symbol, wherein the initial OFDM symbol is a copy of a second OFDM symbol, wherein the second OFDM symbol immediately follows the initial OFDM symbol, and wherein the second OFDM symbol includes at least one of a physical sidelink shared data channel or a physical sidelink control channel.

2. The method according to claim 1, in, The sidelink transmission includes 6 symbols.

3. The method according to claim 2, in, The second symbol and the sixth symbol of the sidelink transmission are demodulation reference signals DM-RS.

4. The method according to claim 1, in, The sidelink transmission includes 7 symbols.

5. The method according to claim 4, in, The second symbol and the sixth symbol of the sidelink transmission are demodulation reference signals DM-RS.

6. The method according to claim 1, further comprising: The UE (102): reserving a first set of resources for the sidelink transmission; and A second set of resources is reserved for a second transmission process.

7. The method according to claim 6, in, The first set of resources and the second set of resources are shifted in time relative to each other.

8. The method according to claim 1, further comprising: The UE (102): Information for reserving resources for the sidelink transmission is transmitted to a second UE (102).

9. The method according to claim 8, in, The information transmitted to the second UE (102) for reserving resources for the sidelink transmission also includes resources for an acknowledgement to be received from the second UE (102).

10. The method according to claim 1, further comprising: The UE (102): The resource is sensed during a sensing window.

11. The method according to claim 10, in, The sensing window occurs prior to selecting the sidelink resource for the sidelink transmission, and wherein a duration of the sensing window is configurable per resource pool.

12. A user equipment UE, comprising: Memory; and a processing circuit in communication with the memory and configured to: selecting a sidelink resource for a sidelink transmission; as well as The sidelink transmission is transmitted on the selected sidelink resource, wherein the sidelink transmission includes an initial orthogonal frequency division multiplexing (OFDM) symbol, wherein the initial OFDM symbol is a copy of a second OFDM symbol, wherein the second OFDM symbol immediately follows the initial OFDM symbol, and wherein the second OFDM symbol includes at least one of a physical sidelink shared data channel or a physical sidelink control channel.

13. The UE according to claim 12, in, When the sidelink transmission includes 6 symbols or 7 symbols, the second symbol and the sixth symbol of the sidelink transmission are demodulation reference signals DM-RS.

14. The UE according to claim 12, in, The processing circuit is further configured to: reserving a first set of resources for the sidelink transmission; and A second set of resources is reserved for a second transmission process, wherein the first set of resources and the second set of resources are offset in time relative to each other.

15. The UE according to claim 12, in, The processing circuit is further configured to: Information for reserving resources for the sidelink transmission is transmitted to a second UE, wherein the information for reserving resources for the sidelink transmission to the second UE also includes resources for an acknowledgement to be received from the second UE.

16. A non-transitory computer-readable storage medium storing instructions for being executed by one or more processors to perform operations for communication by a user equipment (UE), the operations being configured to configure the one or more processors to: selecting a sidelink resource for sidelink transmission; and transmitting the sidelink transmission on the selected sidelink resource, wherein: The sidelink transmission comprises an initial orthogonal frequency division multiplexing (OFDM) symbol, wherein the initial OFDM symbol is a copy of a second OFDM symbol, wherein the second OFDM symbol immediately follows the initial OFDM symbol, and wherein the second OFDM symbol comprises at least one of a physical sidelink shared data channel or a physical sidelink control channel.

17. The non-transitory computer readable storage medium of claim 16, in, When the sidelink transmission includes 6 symbols or 7 symbols, the second symbol and the sixth symbol of the sidelink transmission are demodulation reference signals DM-RS.

18. The non-transitory computer readable storage medium of claim 16, in, The operations further configure the one or more processors to: reserving a first set of resources for the sidelink transmission; and A second set of resources is reserved for a second transmission process, wherein the first set of resources and the second set of resources are offset in time relative to each other.

19. The non-transitory computer readable storage medium of claim 16, in, The operations further configure the one or more processors to: Information for reserving resources for the sidelink transmission is transmitted to a second UE, wherein the information for reserving resources for the sidelink transmission to the second UE also includes resources for an acknowledgement to be received from the second UE.

20. A computer program product comprising a computer program which, when executed by a processor, causes the processor to perform the method according to any one of claims 1 to 11.

Images