NR V2X method for congestion control

Abstract

Methods, devices, and systems for congestion control in a wireless communication system. Some embodiments include receiving a plurality of region configurations, for each of the plurality of region configurations, receiving a channel busy rate (CBR) threshold and a mapping of a region identification (ID) to a resource pool; and measuring the CBR of the resource pool which the WTRU is currently configured to have. If the measured CBR satisfies a CBR threshold of a first zone configuration of the plurality of zone configurations, the WTRU is configured with the first zone configuration, the WTRU is configured with a zone ID based on the first zone configuration and a location of the WTRU, and the WTRU is configured with a resource pool based on the mapping and the configured zone ID.

Description

[0001] This application is a divisional application of the invention patent application with application number 201980053070.4 filed on August 7, 2019 and invention name “NR V2X Method for Congestion Control”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims the benefit of U.S. Provisional Application No. 62 / 715,575, filed on August 7, 2018, U.S. Provisional Application No. 62 / 789,802, filed on January 8, 2019, U.S. Provisional Application No. 62 / 804,487, filed on February 12, 2019, and U.S. Provisional Application No. 62 / 840,933, filed on April 30, 2019, the contents of each of which are hereby incorporated by reference into this document. Background Art

[0004] Congestion control may refer to adjusting transmission parameters of a wireless transmit / receive unit (WTRU) in a wireless communication system based on the congestion level of the system. Congestion control may be used to avoid system overload and to efficiently utilize system resources. Summary of the invention

[0005] Some embodiments provide a method implemented in a wireless transmit / receive unit (WTRU). The method includes receiving a plurality of area configurations, receiving, for each of the plurality of area configurations, a channel busy rate (CBR) threshold and a mapping of an area identifier (ID) to a resource pool; and measuring the CBR of the resource pool with which the WTRU is currently configured. If the measured CBR satisfies the CBR threshold of a first area configuration of the plurality of area configurations, the WTRU is configured with the first area configuration, the WTRU is configured with an area ID based on the first area configuration and the location of the WTRU, and the WTRU is configured with a resource pool based on the mapping and the configured area ID.

[0006] In some embodiments, each of the plurality of area configurations indicates a maximum transmit power (Pmax) value for the WTRU. In some embodiments, the WTRU receives a maximum transmit power (Pmax) value for the WTRU for each of the plurality of area configurations. In some embodiments, if the measured CBR satisfies the CBR threshold of the first area configuration, the WTRU is configured with the maximum transmit power (Pmax) value based on the first area configuration. In some embodiments, each of the plurality of area configurations indicates an area size. In some embodiments, each of the plurality of area configurations includes an area size parameter. In some embodiments, each of the plurality of area configurations indicates an area dimension of the area configuration. In some embodiments, each of the plurality of area configurations indicates an area length (L) and an area width (W) of the area configuration. In some embodiments, each of the plurality of area configurations indicates the number of area IDs of the area configuration. In some embodiments, each of the plurality of area configurations indicates the length (N) of the configured area. X ) and the width of the region (N Y ) is the number of regions on .

[0007] Some embodiments provide a WTRU comprising a transceiver and a processor. The transceiver is configured to receive a plurality of zone configurations. The transceiver is further configured to receive, for each of the plurality of zone configurations, a channel busy rate (CBR) threshold and a mapping of a zone identifier (ID) to a resource pool. The processor is coupled to the transceiver and configured to measure the CBR of the resource pool with which the WTRU is currently configured. The processor is further configured to: if the measured CBR satisfies the CBR threshold corresponding to a first zone configuration of the plurality of zone configurations, configure the first zone configuration for the WTRU, configure a zone ID for the WTRU based on the first zone configuration and a location of the WTRU, and configure a resource pool for the WTRU based on the mapping and the configured zone ID.

[0008] In some embodiments, each of the plurality of area configurations indicates a maximum transmit power (Pmax) value for the WTRU. In some embodiments, the transceiver is further configured to receive, for each of the plurality of area configurations, a maximum transmit power (Pmax) value for the WTRU. In some embodiments, the processor is further configured to configure the WTRU with a maximum transmit power (Pmax) value based on the first area configuration if the measured CBR satisfies a CBR threshold for the first area configuration. In some embodiments, each of the plurality of area configurations indicates an area size. In some embodiments, each of the plurality of area configurations includes an area size parameter. In some embodiments, each of the plurality of area configurations indicates an area dimension of the area configuration. In some embodiments, each of the plurality of area configurations indicates an area length (L) and an area width (W) of the area configuration. In some embodiments, each of the plurality of area configurations indicates a number of area IDs of the area configuration. In some embodiments, each of the plurality of area configurations indicates a length (N) of the configured area. X ) and the width of the region (N Y ) is the number of regions on . BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The present invention may be understood in more detail from the following description given by way of example in conjunction with the accompanying drawings, in which like reference numerals represent like elements, and in which:

[0010] Figure 1A is a system diagram illustrating an example communication system in which one or more disclosed embodiments may be implemented;

[0011] Figure 1B is a diagram showing that according to an embodiment, Figure 1A A system diagram of an exemplary wireless transmit / receive unit (WTRU) for use within the communication system shown;

[0012] Figure 1C is a diagram showing that according to an embodiment, Figure 1A A system diagram of an example radio access network (RAN) and an example core network (CN) used within a communication system as shown in FIG.

[0013] Figure 1D is a diagram showing that according to an embodiment, Figure 1A A system diagram of another example RAN and another example CN used within the communication system shown in;

[0014] Figure 2 is a resource pool configuration diagram illustrating an example resource pool configuration;

[0015] Figure 3is a block diagram illustrating an example zone configuration;

[0016] Figure 4 is a flow chart illustrating an exemplary method for selecting a zone configuration based on a congestion level of a transmission medium;

[0017] Figure 5 is a resource pool configuration diagram illustrating an example resource pool configuration;

[0018] Figure 6 is a block diagram illustrating an example of resource selection for different beam scanning modes;

[0019] Figure 7 a resource diagram illustrating exemplary resource selection for packet transmission;

[0020] Figure 8 is a block diagram illustrating an exemplary packet drop pattern for different priority resource reservations; and

[0021] Fig. 9 is a flow chart illustrating an example method for zone configuration. DETAILED DESCRIPTION

[0022] Figure 1A 1 is a diagram illustrating an example communication system 100 in which one or more disclosed embodiments may be implemented. The communication system 100 may be a multiple access system that provides content such as voice, data, video, messaging, broadcast, etc. to multiple wireless users. The communication system 100 may enable multiple wireless users to access such content by sharing system resources including wireless bandwidth. For example, the communication system 100 may employ one or more channel access methods, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single carrier FDMA (SC-FDMA), zero tail unique word DFT-spread OFDM (ZT UW DTS-s OFDM), unique word OFDM (UW-OFDM), resource block filtered OFDM, filter bank multi-carrier (FBMC), etc.

[0023] like Figure 1AAs shown, the communication system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, RAN 104 / 113, CN 106 / 115, public switched telephone network (PSTN) 108, Internet 110 and other networks 112, but it should be understood that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and / or network components. Each of the WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and / or communicate in a wireless environment. By way of example, the WTRUs 102a, 102b, 102c, 102d (any of which may be referred to as a “station” and / or “STA”) may be configured to transmit and / or receive wireless signals and may include user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a subscription-based unit, a pager, a cellular phone, a personal digital assistant (PDA), a smart phone, a laptop, a netbook, a personal computer, a wireless sensor, a hotspot or MiFi device, an Internet of Things (IoT) device, a watch or other wearable device, a head-mounted display (HMD), a vehicle, a drone, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in an industrial and / or automated process chain environment), a consumer electronic device, a device operating on a commercial and / or industrial wireless network, etc. Any of the WTRUs 102a, 102b, 102c, and 102d may be interchangeably referred to as a UE.

[0024] The communication system 100 may also include a base station 114a and / or a base station 114b. Each of the base stations 114a, 114b may be any type of device that is configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks, such as the CN 106 / 115, the Internet 110, and / or other networks 112. By way of example, the base stations 114a, 114b may be a base transceiver station (BTS), a Node B, an eNode B, a Home Node B, a Home eNode B, a gNB, an NR Node B, a site controller, an access point (AP), a wireless router, and the like. While each of the base stations 114a, 114b is depicted as a single component, it will be appreciated that the base stations 114a, 114b may include any number of interconnected base stations and / or network components.

[0025] The base station 114a may be part of the RAN 104 / 113, which may also include other base stations and / or network components (not shown), such as a base station controller (BSC), a radio network controller (RNC), a relay node, etc. The base station 114a and / or the base station 114b may be configured to send and / or receive wireless signals on one or more carrier frequencies (which may be referred to as cells (not shown)). These frequencies may be in a licensed spectrum, an unlicensed spectrum, or a combination of licensed and unlicensed spectrums. A cell may provide coverage of wireless services to a specific geographic area, which may be relatively fixed or may change over time. The cell may be further divided into cell sectors. For example, a cell associated with the base station 114a may be divided into three sectors. Therefore, in one embodiment, the base station 114a may include three transceivers, i.e., one transceiver for each sector of the cell. In an embodiment, the base station 114a may employ multiple-input multiple-output (MIMO) technology, and may use multiple transceivers for each sector of the cell. For example, beamforming may be used to transmit and / or receive signals in a desired spatial direction.

[0026] The base stations 114a, 114b may communicate with one or more of the WTRUs 102a, 102b, 102c, 102d via an air interface 116, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, centimeter wave, micrometer wave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 116 may be established using any suitable radio access technology (RAT).

[0027] More specifically, as described above, the communication system 100 may be a multiple access system and may employ one or more channel access schemes such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, etc. For example, the base station 114a in the RAN 104 / 113 and the WTRUs 102a, 102b, 102c may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may establish an air interface 115 / 116 / 117 using Wideband CDMA (WCDMA). WCDMA may include communication protocols such as High Speed ​​Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA may include High Speed ​​Downlink (DL) Packet Access (HSDPA) and / or High Speed ​​UL Packet Access (HSUPA).

[0028] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface 116 using Long Term Evolution (LTE) and / or Advanced LTE (LTE-A) and / or Advanced LTE Pro (LTE-A Pro).

[0029] In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as NR radio access, which may establish the air interface 116 using New Radio (NR).

[0030] In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement multiple radio access technologies. For example, the base station 114a and the WTRUs 102a, 102b, 102c may together implement LTE radio access and NR radio access, for example using dual connectivity (DC) principles. Thus, the air interface used by the WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and / or transmissions sent to / from multiple types of base stations, such as eNBs and gNBs.

[0031] In other embodiments, the base station 114a and the wireless transmit / receive units 102a, 102b, and 102c may implement wireless technologies, such as IEEE802.11 (i.e., Wireless Fidelity (WiFi), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000EV-DO, International Standard 2000 (IS-2000), International Standard 95 (IS-95), International Standard 856 (IS-856), Global System for Mobile Communications (GSM), Enhanced Data Rates for GSM Evolution (EDGE), GSM EDGE (GERAN), etc.

[0032] Figure 1AThe base station 114b in the example may be, for example, a wireless router, a Home NodeB, a Home eNodeB, or an access point, and may utilize any suitable RAT to facilitate wireless connectivity in a local area, such as a business location, a residence, a vehicle, a campus, an industrial facility, an air corridor (e.g., for use by drones), a road, and the like. In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement radio technologies such as IEEE 802.11 to establish a wireless local area network (WLAN). In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement radio technologies such as IEEE 802.15 to establish a wireless personal area network (WPAN). In another embodiment, the base station 114b and the WTRUs 102c, 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE-A Pro, NR, etc.) to establish a picocell or a femtocell. Figure 1A As shown, the base station 114b may be directly connected to the Internet 110. Therefore, the base station 114b may not need to access the Internet 110 via the CN 106 / 115.

[0033] The RAN 104 / 113 may be in communication with the CN 106 / 115, which may be any type of network that provides voice, data, applications, and / or voice over Internet Protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may have different quality of service (QoS) requirements, such as different throughput requirements, latency requirements, fault tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, etc. The CN 106 / 115 may provide call control, billing services, mobile location-based services, pre-paid calls, Internet connectivity, video distribution, etc., and / or perform high-level security functions (e.g., user authentication). Although Figure 1A Although not shown, it will be appreciated that the RAN 104 / 113 and / or the CN 106 / 115 may be in direct or indirect communication with other RANs that employ the same RAT or a different RAT as the RAN 104 / 113. For example, in addition to being connected to the RAN 104 / 113, which may utilize NR radio technology, the CN 106 / 115 may also be in communication with another RAN (not shown) employing GSM, UMTS, CDMA 2000, WiMAX, E-UTRA, or WiFi radio technology.

[0034] The CN 106 / 115 may also act as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and / or other networks 112. The PSTN 108 may include a circuit-switched telephone network that provides plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communication protocols, such as the Transmission Control Protocol (TCP), the User Datagram Protocol (UDP), and / or the Internet Protocol (IP) in the TCP / IP Internet protocol suite. The networks 112 may include wired and / or wireless communication networks owned and / or operated by other service providers. For example, the networks 112 may include another CN connected to one or more RANs, which may use the same RAT as the RAN 104 / 113 or a different RAT.

[0035] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communication system 100 may include multi-mode capabilities (e.g., the WTRUs 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks via different wireless links). Figure 1A The illustrated WTRU 102c may be configured to communicate with the base station 114A, which may employ a cellular-based radio technology, and with the base station 114b, which may employ an IEEE 802 radio technology.

[0036] Figure 1B is a system diagram illustrating an example WTRU 102. Figure 1B As shown, the WTRU 102 may include, among other things, a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a keyboard 126, a display / touchpad 128, non-removable memory 130, a removable memory 132, a power source 134, a global positioning system (GPS) chipset 136, and / or other peripherals 138. It will be appreciated that the WTRU 102 may include any sub-combination of the foregoing elements while remaining consistent with an embodiment.

[0037] The processor 118 may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) circuit, any other type of integrated circuit (IC), a state machine, etc. The processor 118 may perform signal coding, data processing, power control, input / output processing, and / or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit / receive element 122. Although Figure 1B The processor 118 and the transceiver 120 are depicted as separate components, but it will be appreciated that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0038] The transmit / receive component 122 may be configured to transmit or receive signals to or from a base station (e.g., base station 114a) via an air interface 116. For example, in one embodiment, the transmit / receive component 122 may be an antenna configured to transmit and / or receive RF signals. In one embodiment, the transmit / receive component 122 may be a transmitter / detector configured to transmit and / or receive, for example, IR, UV, or visible light signals. In yet another embodiment, the transmit / receive component 122 may be configured to transmit and / or receive both RF and optical signals. It should be understood that the transmit / receive component 122 may be configured to transmit and / or receive any combination of wireless signals.

[0039] Although the transmit / receive element 122 is Figure 1B Although depicted as a single component in the embodiment, the WTRU 102 may include any number of transmit / receive components 122. More specifically, the WTRU 102 may employ MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit / receive components 122 (e.g., multiple antennas) for transmitting and receiving wireless signals over the air interface 116.

[0040] The transceiver 120 may be configured to modulate signals to be transmitted by the transmit / receive element 122 and to demodulate signals received by the transmit / receive element 122. As described above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers to enable the WTRU 102 to communicate via multiple RATs (e.g., NR and IEEE 802.11).

[0041] The processor 118 of the WTRU 102 may be coupled to and may receive user input data from a speaker / microphone 124, a keyboard 126, and / or a display / touchpad 128 (e.g., a liquid crystal display (LCD) display unit or an organic light emitting diode (OLED) display unit). The processor 118 may also output user data to the speaker / microphone 124, the keyboard 126, and / or the display / touchpad 128. In addition, the processor 118 may access information from and store data in any type of suitable memory, such as a non-removable memory 130 and / or a removable memory 132. The non-removable memory 130 may include a random access memory (RAM), a read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. In other embodiments, the processor 118 may access information from and store data in a memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0042] The processor 118 may receive power from the power source 134, and may be configured to distribute and / or control power to other components in the WTRU 102. The power source 134 may be any suitable device for powering the WTRU 102. For example, the power source 134 may include one or more dry cell batteries (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel-metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, etc.

[0043] The processor 118 may also be coupled to the GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to or in lieu of the information from the GPS chipset 136, the WTRU 102 may receive location information from a base station (e.g., base stations 114a, 114b) over the air interface 116 and / or determine its location based on the timing of signals received from two or more neighboring base stations. It will be appreciated that the WTRU 102 may acquire location information by any suitable location-determination method while remaining consistent with an embodiment.

[0044] The processor 118 may also be coupled to other peripherals 138, which may include one or more software and / or hardware modules that provide additional features, functionality, and / or wired or wireless connectivity. For example, the peripherals 138 may include an accelerometer, an electronic compass, a satellite transceiver, a digital camera (for photos and / or video), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands-free headset, module, a frequency modulation (FM) radio unit, a digital music player, a media player, a video game player module, an Internet browser, a virtual reality and / or augmented reality (VR / AR) device, an activity tracker, etc. The peripheral device 138 may include one or more sensors, which may be one or more of a gyroscope, an accelerometer, a Hall effect sensor, a magnetometer, an orientation sensor, a proximity sensor, a temperature sensor, a time sensor, a geolocation sensor, an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, and / or a humidity sensor.

[0045] The WTRU 102 may include a full-duplex radio for which transmission and reception of some or all signals (e.g., signals associated with specific subframes for UL (e.g., for transmission) and downlink (e.g., for reception)) may be concurrent and / or simultaneous. The full-duplex radio may include an interference management unit 139 that reduces and / or substantially eliminates self-interference by means of hardware (e.g., chokes) or by signal processing by a processor (e.g., a separate processor (not shown) or by the processor 118). In an embodiment, the WTRU 102 may include a half-duplex radio for transmitting and receiving some or all signals (e.g., signals associated with specific subframes for UL (e.g., for transmission) or downlink (e.g., for reception)).

[0046] Figure 1C 1 is a system diagram showing the RAN 104 and the CN 106 in accordance with an embodiment. As described above, the RAN 104 may employ an E-UTRA radio technology and communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0047] The RAN 104 may include eNode-Bs 160a, 160b, 160c, though it will be appreciated that the RAN 104 may include any number of eNode-Bs while remaining consistent with an embodiment. Each of the eNode-Bs 160a, 160b, 160c may include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the eNode-Bs 160a, 160b, 160c may implement MIMO technology. Thus, for example, the eNode-B 160a may use multiple antennas to transmit wireless signals to and / or receive wireless signals from the WTRU 102a.

[0048] Each of the eNodeBs 160a, 160b, 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the UL and / or DL, etc. Figure 1C As shown in FIG. , the eNode-Bs 160a, 160b, 160c may communicate with one another via an X2 interface.

[0049] Figure 1C The CN 106 shown in FIG. 1 may include a mobility management entity (MME) 162, a serving gateway (SGW) 164, and a packet data network (PDN) gateway (or PGW) 166. Although each of the foregoing components is depicted as part of the CN 106, it will be understood that any of these components may be owned and / or operated by an entity other than a CN operator.

[0050] The MME 162 may be connected to each of the eNode-Bs 162a, 162b, 162c in the RAN 104 via an S1 interface and may serve as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, bearer activation / deactivation, selecting a particular serving gateway during an initial attach of the WTRUs 102a, 102b, 102c, etc. The MME 162 may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other wireless technologies, such as GSM and / or WCDMA.

[0051] The SGW 164 may be connected to each of the eNode-Bs 160a, 160b, 160c in the RAN 104 via an S1 interface. The SGW 164 may generally route and forward user data packets to / from the WTRUs 102a, 102b, 102c. The SGW 164 may perform other functions, such as anchoring the user plane during inter-eNode-B handovers, triggering paging when DL data is available for the WTRUs 102a, 102b, 102c, managing and storing the contexts of the WTRUs 102a, 102b, 102c, and the like.

[0052] The SGW 164 may be connected to the PGW 166, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0053] The CN 106 may facilitate communications with other networks. For example, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices. For example, the CN 106 may include, or may be in communication with, an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that serves as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers.

[0054] Although the WTRU Figures 1A-1D Although described as a wireless terminal, it is contemplated that in certain representative embodiments such a terminal may use (eg, temporarily or permanently) a wired communications interface with a communications network.

[0055] In a representative embodiment, other network 112 may be a WLAN.

[0056] A WLAN in an infrastructure basic service set (BSS) mode may have an access point (AP) for a BSS and one or more stations (STAs) associated with the AP. The AP may access or dock to a distribution system (DS) or another type of wired / wireless network that sends traffic into and / or out of the BSS. Traffic initiated from outside the BSS and destined for the STA may be reached through the AP and may be delivered to the STA. Traffic initiated from the STA and destined for a destination outside the BSS may be sent to the AP to be delivered to the corresponding destination. Traffic between STAs within the BSS may be sent through the AP, for example, where the source STA may send traffic to the AP, and the AP may deliver traffic to the destination STA. Traffic between STAs within the BSS may be considered and / or referred to as point-to-point traffic. The point-to-point traffic may be sent between the source STA and the destination STA (e.g., directly between the source STA and the destination STA) using a direct link setup (DLS). In certain representative embodiments, the DLS may use 802.11e DLS or 802.11z tunnel DLS (TDLS). A WLAN using an independent BSS (IBSS) mode may not have an AP, and STAs (eg, all STAs) within or using the IBSS may communicate directly with each other. The IBSS communication mode may sometimes be referred to herein as an "ad hoc" communication mode.

[0057] When using the 802.11ac infrastructure operating mode or a similar operating mode, the AP can transmit beacons on a fixed channel, such as a primary channel. The primary channel can be a fixed width (e.g., a 20MHz wide bandwidth) or a width dynamically set via signaling. The primary channel can be a working channel of the BSS and can be used by the STA to establish a connection with the AP. In certain representative embodiments, such as in an 802.11 system, carrier sensing multiple access (CSMA / CA) with collision avoidance can be implemented. For CSMA / CA, STAs including the AP (e.g., each STA) can sense the main channel. If the main channel is sensed / detected and / or determined to be busy by a specific STA, the specific STA can back off. One STA (e.g., only one station) can transmit at any given time in a given BSS.

[0058] A high throughput (HT) STA may communicate using a 40 MHz wide channel, for example, by combining a primary 20 MHz channel with an adjacent or non-adjacent 20 MHz channel to form a 40 MHz wide channel.

[0059] Very high throughput (VHT) STA can support channels with a width of 20MHz, 40MHz, 80MHz and / or 160MHz. 40MHz and / or 80MHz channels can be formed by combining continuous 20MHz channels. A 160MHz channel can be formed by combining 8 continuous 20MHz channels, or by combining two non-continuous 80MHz channels, which can be referred to as an 80+80 configuration. For the 80+80 configuration, after channel coding, the data can pass through a segment parser that can divide the data into two streams. Each stream can be subjected to inverse fast Fourier transform (IFFT) processing and time domain processing, respectively. The stream can be mapped onto two 80MHz channels, and the data can be transmitted by the transmitting STA. At the receiver of the receiving STA, the operation of the above 80+80 configuration can be opposite, and the combined data can be sent to the medium access control (MAC).

[0060] The operating mode below 1 GHz is supported by 802.11af and 802.11ah. The channel operating bandwidth and carrier are reduced in 802.11af and 802.11ah relative to the channel operating bandwidth and carrier used in 802.11n and 802.11ac. 802.11af supports 5MHz, 10MHz and 20MHz bandwidths in the TV White Space (TVWS) spectrum, while 802.11ah supports 1MHz, 2MHz, 4MHz, 8MHz and 16MHz bandwidths using non-TVWS spectrum. According to a representative embodiment, 802.11ah can support metering type control / machine type communication, such as MTC devices in macro coverage areas. MTC devices may have certain capabilities, for example, limited capabilities including support for certain and / or limited bandwidths (e.g., only support for certain and / or limited bandwidths). MTC devices may include batteries with battery life above a threshold (e.g., to maintain very long battery life).

[0061] A WLAN system that can support multiple channels and channel bandwidths (e.g., 802.11n, 802.11ac, 802.11af, and 802.11ah) includes a channel that can be designated as a primary channel. The primary channel may have a bandwidth equal to the maximum common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel may be set and / or limited by the STA among all STAs operating in the BSS, and the STA supports the minimum bandwidth operating mode. In the example of 802.11ah, for STAs (e.g., MTC-type devices) that support (e.g., only support) a 1MHz mode, the primary channel may be 1MHz wide, even if the AP and other STAs in the BSS support 2MHz, 4MHz, 8MHz, 16MHz, and / or other channel bandwidth operating modes. Carrier sensing and / or network allocation vector (NAV) settings may depend on the state of the primary channel. If the primary channel is busy, for example, because a STA (which only supports a 1MHz operating mode) transmits to the AP, the entire available band may be considered busy even if most of the bands in the band remain idle and available.

[0062] In the United States, the available frequency band that 802.11ah can use is from 902MHz to 928MHz. In South Korea, the available frequency band is from 917.5MHz to 923.5MHz. In Japan, the available frequency band is from 916.5MHz to 927.5MHz. Depending on the country code, the total bandwidth available for 802.11ah is 6MHz to 26MHz.

[0063] Figure 1D 1 is a system diagram showing the RAN 113 and the CN 115 according to an embodiment. As described above, the RAN 113 may communicate with the WTRUs 102a, 102b, 102c over the air interface 116 using NR radio technology. The RAN 113 may also communicate with the CN 115.

[0064] The RAN 113 may include gNBs 180a, 180b, 180c, but it will be appreciated that the RAN 113 may include any number of gNBs while remaining consistent with the embodiment. Each of the gNBs 180a, 180b, 180c may include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the gNBs 180a, 180b, 180c may implement MIMO technology. For example, the gNBs 180a, 180b may utilize beamforming to transmit signals to and / or receive signals from the gNBs 180a, 180b, 180c. Thus, the gNB 180a may, for example, use multiple antennas to transmit wireless signals to and / or receive wireless signals from the WTRU 102a. In one embodiment, the gNBs 180a, 180b, 180c may implement carrier aggregation techniques. For example, the gNB 180a may transmit multiple component carriers (not shown) to the WTRU 102a. A subset of these component carriers may be on an unlicensed spectrum, while the remaining component carriers may be on a licensed spectrum. In an embodiment, the gNBs 180a, 180b, 180c may implement coordinated multi-point (CoMP) techniques. For example, the WTRU 102a may receive coordinated transmissions from the gNB 180a and gNB 180b (and / or gNB 180c).

[0065] The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using transmissions associated with scalable parameter configurations (numerology). For example, OFDM symbol spacing and / or OFDM subcarrier spacing may vary for different transmissions, different cells, and / or different portions of the wireless transmission spectrum. The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using subframes or subframes or transmission time intervals (TTIs) of varying or scalable lengths (e.g., containing different numbers of OFDM symbols and / or continuously varying absolute time lengths).

[0066] The gNBs 180a, 180b, 180c may be configured to communicate with the WTRUs 102a, 102b, 102c in a standalone configuration and / or a non-standalone configuration. In a standalone configuration, the WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c without also accessing other RANs (e.g., the eNode-Bs 160a, 160b, 160c). In a standalone configuration, the WTRUs 102a, 102b, 102c may utilize one or more of the gNBs 180a, 180b, 180c as mobility anchors. In a standalone configuration, the WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using signals in an unlicensed band. In a non-standalone configuration, the WTRUs 102a, 102b, 102c may communicate / connect with the gNBs 180a, 180b, 180c while also communicating / connecting with another RAN, such as the eNode-Bs 160a, 160b, 160c. For example, the WTRUs 102a, 102b, 102c may implement DC principles to communicate with one or more of the gNBs 180a, 180b, 180c and one or more of the eNode-Bs 160a, 160b, 160c substantially simultaneously. In a non-standalone configuration, the eNode-Bs 160a, 160b, 160c may serve as mobility anchors for the WTRUs 102a, 102b, 102c and the gNBs 180a, 180b, 180c may provide additional coverage and / or throughput for serving the WTRUs 102a, 102b, 102c.

[0067] Each of the gNBs 180a, 180b, 180c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, user scheduling in UL and / or DL, support network slicing, dual connectivity, interworking between NR and E-UTRA, route user plane data to a user plane function (UPF) 184a, 184b, route control plane information to an access and mobility management function (AMF) 182a, 182b, etc. Figure 1D As shown, gNBs 180a, 180b, and 180c may communicate with each other via an Xn interface.

[0068] Figure 1DThe CN 115 shown in FIG. 1 may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one session management function (SMF) 183a, 183b, and possible data networks (DNs) 185a, 185b. Although each of the aforementioned components is depicted as part of the CN 115, it will be understood that any of these components may be owned and / or operated by an entity other than a CN operator.

[0069] The AMF 182a, 182b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via an N2 interface and may serve as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRU 102a, 102b, 102c, supporting network slicing (e.g., handling different PDU sessions with different requirements), selecting a specific SMF 183a, 183b, management of registration areas, termination of NAS signaling, mobility management, and the like. The AMF 182a, 182b may use network slicing to customize the CN support of the WTRU 102a, 102b, 102c according to the type of service used by the WTRU 102a, 102b, 102c. For example, different network slices may be established for different use cases, such as services that rely on ultra-reliable low latency (URLLC) access, services that rely on enhanced massive mobile broadband (eMBB) access, services for machine type communication (MTC) access, and the like. The AMF 162 may provide a control plane function for switching between the RAN 113 and other RANs (not shown) that employ other radio technologies, such as LTE, LTE-A, LTE-APro, and / or non-3GPP access technologies such as WiFi.

[0070] The SMF 183a, 183b may be connected to the AMF 182a, 182b in the CN 115 via the N11 interface. The SMF 183a, 183b may also be connected to the UPF 184a, 184b in the CN 115 via the N4 interface. The SMF 183a, 183b may select and control the UPF 184a, 184b, and configure service routing through the UPF 184a, 184b. The SMF 183a, 183b may perform other functions, such as managing and allocating UE IP addresses, managing PDU sessions, controlling policy enforcement and QoS, providing downlink data notification, etc. The PDU session type may be IP-based, non-IP-based, Ethernet-based, etc.

[0071] The UPF 184a, 184b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via the N3 interface, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. The UPF 184, 184b may perform other functions, such as routing and forwarding packets, enforcing user plane policies, supporting multi-homed PDU sessions, handling user plane QoS, buffering downlink packets, providing mobility anchoring, and the like.

[0072] The CN 115 may facilitate communications with other networks. For example, the CN 115 may include an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) or may communicate with an IP gateway that acts as an interface between the CN 115 and the PSTN 108. In addition, the CN 115 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers. In an embodiment, the WTRUs 102a, 102b, 102c may be connected to a local data network (DN) 185a, 185b via an N3 interface to the UPF 184a, 184b and an N6 interface between the UPF 184a, 184b and the DN 185a, 185b, and through the UPF 184a, 184b.

[0073] Given that Figures 1A-1D and Figures 1A-1D In accordance with the corresponding description of the present invention, one or more or all of the functions described herein with respect to one or more of the following items may be performed by one or more simulation devices (not shown): WTRU 102a-d, base station 114a-b, eNodeB 160a-c, MME 162, SGW 164, PGW 166, gNB 180a-c, AMF 182a-ab, UPF184a-b, SMF 183a-b, DN185ab and / or any other device (one or more) described herein. The simulation device may be one or more devices configured to simulate one or more or all of the functions described herein. For example, the simulation device may be used to test other devices and / or simulate network and / or WTRU functions.

[0074] The simulation device can be designed to implement one or more tests of other devices in a laboratory environment and / or an operator network environment. For example, one or more simulation devices can perform one or more or all functions while being fully or partially implemented and / or deployed as part of a wired and / or wireless communication network in order to test other devices within the communication network. One or more simulation devices can perform one or more or all functions while being temporarily implemented / deployed as part of a wired and / or wireless communication network. The simulation device can be directly coupled to another device for testing purposes and / or can perform tests using over-the-air wireless communications.

[0075] One or more simulation devices can perform one or more functions (including all functions) without being implemented / deployed as part of a wired and / or wireless communication network. For example, the simulation device can be used in a test scenario in a test lab and / or a non-deployed (e.g., testing) wired and / or wireless communication network to enable testing of one or more components. The one or more simulation devices can be test devices. The simulation device can transmit and / or receive data using direct RF coupling and / or wireless communication with the aid of RF circuits (e.g., which can include one or more antennas).

[0076] The following abbreviations may be used in this article:

[0077] Δf Subcarrier spacing

[0078] 5gFlex 5G flexible wireless access technology

[0079] 5gNB 5GFlex Node B

[0080] ACK

[0081] BLER Block Error Rate

[0082] BTI Basic TI (an integer multiple of one or more symbol durations)

[0083] CB CB-based contention (e.g., access, channel, resource)

[0084] CBR Channel Busy Rate

[0085] CP Cyclic Prefix

[0086] CP-OFDM Conventional OFDM (relies on cyclic prefix)

[0087] CQI Channel Quality Indicator

[0088] CSI Channel State Information

[0089] CN Core Network (e.g. LTE Packet Core)

[0090] CR Channel occupancy rate

[0091] CR_Limit Channel occupancy limit

[0092] CRC Cyclic Redundancy Check

[0093] CSI Channel State Information

[0094] CSG Closed User Group

[0095] D2D device-to-device transmission (e.g. LTE sidelink)

[0096] DCI Downlink Control Information

[0097] DL Downlink

[0098] DM-RS Demodulation Reference Signal

[0099] DRB Data Radio Bearer

[0100] EPC Evolved Packet Core

[0101] FB Feedback

[0102] FDD Frequency Division Duplex

[0103] FDM Frequency Division Multiplexing

[0104] FR1 Frequency Range 1

[0105] FR2 Frequency Range 2

[0106] ICC Industrial Control and Communications

[0107] ICIC Inter-cell Interference Cancellation

[0108] IP Internet Protocol

[0109] LAA License Assisted Access

[0110] LBT Listen before you speak

[0111] LCH Logical Channel

[0112] LCP Logical Channel Prioritization

[0113] LLC low latency communication

[0114] LTE Long Term Evolution, such as 3GPP LTE R8 and above

[0115] MAC Medium Access Control

[0116] NACK Negative Acknowledgement

[0117] MBB Massive Broadband Communications

[0118] MC Multi-Carrier

[0119] MCS modulation and coding scheme

[0120] MIMO Multiple Input Multiple Output

[0121] MTC Machine Type Communication

[0122] NAS Non-Access Stratum

[0123] OFDM Orthogonal Frequency Division Multiplexing

[0124] OOB Out of Band (Emit)

[0125] Pcmax Total available WTRU (e.g. UE) power in a given TI

[0126] PHY Physical Layer

[0127] PRACH Physical Random Access Channel

[0128] PDU Protocol Data Unit

[0129] PER Packet Error Rate

[0130] PLMN Public Land Mobile Network

[0131] PLR Packet Loss Rate

[0132] PPPP Short Range Communication Data (Prose) Packet Priority

[0133] PPPR Short Range Communications Packet Reliability

[0134] PSS Primary Synchronization Signal

[0135] PSSSH Physical Side Link Shared Channel

[0136] PSSCH Physical Sidelink Control Channel

[0137] QoS Quality of Service (from the perspective of the physical layer)

[0138] RAB Radio Access Bearer

[0139] RACH Random Access Channel (or process)

[0140] RGF Resource Group Format

[0141] RF Radio Front End

[0142] RNTI Radio Network Identifier

[0143] RRC Radio Resource Control

[0144] RRM Radio Resource Management

[0145] RS reference signal

[0146] RSCP Reference Signal Code Power

[0147] RSRP Reference Signal Received Power

[0148] RSRQ Reference Signal Received Quality

[0149] RSSI Received Signal Strength Indicator

[0150] RTT Round Trip Time

[0151] S-RSSI Sidelink Received Signal Strength Indicator

[0152] SCMA Single Carrier Multiple Access

[0153] SDU Service Data Unit

[0154] SOM spectral operation mode

[0155] SL Side Link

[0156] SS Sync Signal

[0157] SSS Secondary synchronization signal

[0158] STRB SL Time Resource Block

[0159] SWG Switching Gap (in self-contained subframe)

[0160] TB Transfer Block

[0161] TDD Time Division Duplex

[0162] TDM Time Division Multiplexing

[0163] TI time interval (one or more integer multiples of BTI)

[0164] TTI Transmission Time Interval (one or more integer multiples of TI)

[0165] TRP Transmission / Reception Point

[0166] TRX Transceiver

[0167] UFMC Universal Filtered Multi-Carrier

[0168] UF-OFDM Universal Filtered OFDM

[0169] UL Uplink

[0170] URLLC Ultra-Reliable and Low-Latency Communications

[0171] V2V Vehicle-to-Vehicle Communication

[0172] V2X vehicle-to-vehicle communications

[0173] VQI V2X 5G QoS Indicator

[0174] WLAN Wireless Local Area Network and related technologies (IEEE 802.xx domain)

[0175] In LTE V2X, the transmission time of a transport block is one subframe. If the PSSCH and PSCCH are adjacent, each transport block including the PSSCH and PSCCH occupies one or more subchannels (one or more); otherwise, each PSSCH occupies one or more subchannels (one or more). Typically, each subchannel includes multiple consecutive physical resource blocks (PRBs) and subchannel sizes, that is, the number of PRBs for each subchannel can be unique for each resource pool. In LTE V2X, the channel busy rate (CBR) and channel occupancy rate (CR) are used as parameters to determine the channel state. The CBR is used to evaluate the congestion level of the system in the resource pool, and the CR is used to determine the channel occupancy of the WTRU in a transmission pool. In the resource pool, if the data and control resources (i.e., PSSCH and PSCCH) are not adjacent, the CBR and CR are evaluated in the data pool. In the various examples here, for ease of description, the term CBR is used to describe congestion, but any congestion measurement can be used in various embodiments.

[0176] If CBR and CR are evaluated in subframe n, the CBR is defined as the portion of subchannels in the resource pool for which the S-RSSI measured by the WTRU is greater than the configured or preconfigured value on subframe [n-100, n-1], and the CR is defined as the total number of subchannels used for their transmission in subframe [na, n-1] and authorized in subframe [n, n+b] divided by the total number of subchannels in the transmission pool configured on [na, n+b].

[0177] In LTE V2X, congestion control mechanisms are implemented in terms of resource selection and transport block transmission period. During the resource selection period, the WTRU may adjust the following parameters based on the CBR of the resource pool and the PPPP of the packet to be processed: maximum transmit power; range of number of retransmissions per TB; range of number of subchannels used for PSSCH; and range of MCS.

[0178] For each CBR range, the WTRU is configured or pre-configured with a list of channel occupancy limits, each corresponding to a PPPP. When the WTRU has a configured grant and data is available for transmission, it may need to ensure that its CR does not exceed cr_limit, which is the maximum channel occupancy of the WTRU corresponding to the PPPP, including transmission and / or discarding of TBs.

[0179] New instances may be defined in frequencies FR1 and FR2 (i.e., up to 52.6 GHz) used for sidelink communications. A common design may be used for FR1 and FR2. In high frequencies, beam-based communications may be used to compensate for high propagation losses. Thus, the WTRU may perform beam scanning to cover multiple directions in broadcast-based services.

[0180] In NR V2X, it may be expected that users may support different types of services with different latency requirements. Therefore, the WTRU may use different transmission formats based on the latency requirements of each packet. For certain (e.g., critical) latency services, the WTRU may perform symbol-based transmissions, and for other (e.g., non-critical) latency services, the WTRU may perform slot-based transmissions. In NR V2X, the WTRU may use beam-based transmissions, and each transmission may have different granularities, such as symbol-based transmissions and slot-based transmissions, depending on the latency requirements of each packet. Therefore, it may be desirable to structure how the WTRU can determine parameters for transmissions with different resource granularities and / or for congestion control for beam-based transmissions.

[0181] The congestion control mechanisms in LTE V2X may be used for NR V2X; however, this approach may result in excessive packet drops. This may be because for congestion control in LTE V2X, channel occupancy is not taken into account when the WTRU performs resource selection or resource reservation. Therefore, if the WTRU evaluates the CR before a TB transmission, it may need to drop the TB if the channel occupancy requirement is not met. In addition, if the CR of the channel is high enough, the WTRU may need to continuously drop packets to reduce the channel occupancy. Therefore, considering congestion control, it may be desirable to structure how the WTRU performs resource selection and transmission parameter adaptation to reduce packet drops.

[0182] Some embodiments include systems, methods, and devices for determining parameters for congestion control. In NR V2X, it may be assumed that the WTRU may calculate the CBR and CR to determine the channel state of the system. The CBR may be used to assess the congestion level of the system, and the CR may be used to assess the channel occupancy of the WTRU. For example, a resource group may be defined as a combination of N resource blocks (one or more) spanning M symbols (one or more), where M or N may be one. A resource group may include M×N resource elements, where each resource element is defined as a resource block spanning one symbol. An exemplary resource group format (RGF) may be defined as a combination of M and N. In some examples, the WTRU determines when to calculate the CBR. For example, the WTRU may calculate the CBR based on one or more of the following events: the WTRU performs resource selection, the WTRU has data available at its transmission buffer, and / or the WTRU is configured for periodic and / or non-periodic CBR reporting.

[0183] Some embodiments include systems, methods, and devices for determining CBR. For example, in some embodiments, the WTRU determines the CBR based on energy sensing and / or SCI decoding. The CBR can be defined as the portion of a resource group (RG) that is occupied on a configured resource group. A resource group may be considered occupied if one or any combination of the following conditions is met: its measured or estimated S-RSSI / RSRP / RSCP is greater than a threshold; or, it is reserved by another WTRU, which can be determined by decoding an SCI. In some examples, the CBR may be defined as the ratio of an occupied transmission mode to a configured mode. The method can be used, for example, to calculate the CBR for a resource pool with pattern-based transmissions. In some examples, the WTRU may determine that a transmission mode is occupied if one or any combination of the following conditions exists: the WTRU decodes an SCI that reserves one or more modes, and / or the WTRU determines that resources in a mode are occupied.

[0184] In some embodiments, the WTRU determines availability for CBR calculation based on properties of the data available for transmission. For example, in some embodiments, the WTRU may determine the availability / occupancy of resources for CBR calculation based on properties of the data to be transmitted (e.g., QoS). In some embodiments, for example, the WTRU may determine the CBR based on measurements of resource availability, such as deriving the CBR from sensing results. The criteria for determining such availability may depend on the QoS of the packets to be transmitted, and / or the packets in the WTRU's transmit buffer, such as when the CBR is determined.

[0185] In some embodiments, the WTRU may be configured with multiple thresholds (e.g., RSRP, RSSI, etc.) to determine the availability of resources. In some embodiments, the WTRU may select different thresholds based on the QoS of the TB. In some embodiments, the WTRU may then determine the CBR based on the resulting availability determined using different RSRP thresholds. For example, this approach may be used if the WTRU calculates the CBR in anticipation of performing resource selection.

[0186] In some embodiments, the WTRU may be configured with multiple RSRP thresholds to determine availability in the CBR calculation based on the percentage of available data in its transmit buffer associated with different QoS classes. For example, if the WTRU has more than a certain number of bytes of data (for convenience, X bytes) in its buffer associated with a particular QoS class, the WTRU may use a certain threshold (for convenience, Threshold_X) to determine availability when considering SCI transmissions received by other WTRUs.

[0187] In some embodiments, the WTRU may calculate the CBR in a window after the CBR calculation timeslot. For example, if the WTRU is triggered to calculate the CBR in timeslot n, the WTRU may calculate the CBR by considering the resource availability in the window [n+T1, n+T2], where T2 may be determined by the QoS of the TB(s) to be processed or may be (pre)configured. This approach may be used, for example, in the case where the WTRU calculates the CBR during the resource allocation procedure.

[0188] In some embodiments, the WTRU may calculate the CBR based on configured parameters. For example, the network may configure the WTRU via the SIB or RRC with one or any combination of the following parameters to calculate the CBR of the resource pool: resource group format; resource availability threshold; and / or measurement window (e.g., duration of the window, time offset of the measurement window, etc.). This approach may be employed, for example, to provide the network with CBR information at a certain transmission granularity within a period, which may, for example, help the network to schedule resources correctly.

[0189] In some embodiments, the WTRU determines the CBR of one resource pool based on the CBR of another resource pool. For example, the WTRU may use the CBR calculated in the control resource pool to determine the CBR in the data resource pool, and vice versa. For example, this method may be employed in a pattern-based resource pool, for example, where the congestion levels of the data and control resource pools may be similar. In some embodiments, the WTRU determines the CBR of a resource pool based on configured parameters. For example, the WTRU may calculate the CBR using the configured parameters. In some examples, the network may configure the WTRU via the SIB or RRC with one or any combination of the following parameters to calculate the CBR of the resource pool: resource group format; resource availability threshold; and / or measurement window (e.g., duration of the window, time offset of the measurement window, etc.).

[0190] In some cases, determining the CBR based on configured parameters may have the advantage of allowing the network to have accurate information about the CBR for a specific transmission granularity within a time period, which may facilitate the network's scheduling of resources. The CR may be defined as the total number of RGs used for its transmission and the RGs reserved for future transmissions divided by the total number of RGs configured in the resource pool within a specific time period. In some examples, the WTRU may calculate one or more CBRs, where each CBR may be associated with one or any combination of the following: a beam; a beam group; or a resource group format. In some examples, the WTRU may calculate one or more CBRs for a beam. The WTRU may associate a receive beam with a transmit beam. Measurements and calculations such as the CBR of a receive beam may be used to determine the transmission behavior of its associated transmit beam. For a beam, the WTRU may calculate one or more CBRs (one or more), where each CBR (one or more) may be associated with a resource group format. The WTRU may calculate CBRs for all resource group formats.

[0191] The method may be motivated by an example scenario where a WTRU has one or more unicast links with multiple WTRUs. Thus, the WTRU may calculate one or more CBRs, where each CBR may be associated with one unicast link. The CBRs for all resource group formats may be calculated based on any one or combination of: the (pre-)configured resource group format for CBR calculation; the resource group format with the lowest value M among the (pre-)configured resource group formats; the resource group format with the lowest value N among the (pre-)configured resource group formats; a resource group format with M=N=1; a resource group format where M=1 and N belongs to one of the configured resource group formats; or a group format where N=1 and M belongs to one of the configured resource group formats.

[0192] In another example, the WTRU may calculate a CBR for a beam group. The WTRU may associate one or more receive beams with one or more transmit beams. The CBR calculation for the receive beam(s) may be used to determine the transmission behavior of its associated transmit beam. For a beam group, the WTRU may calculate one or more CBRs, each of which may correspond to a resource group format. The WTRU may calculate a CBR for all resource group formats.

[0193] This approach may be motivated by multicast or broadcast scenarios where the WTRU may perform beam scanning in multiple directions. Therefore, for packets broadcast in multiple directions, the WTRU may need a CBR for the beam groups involved in the scanning process. The WTRU may determine a beam group with high spatial correlation for one CBR calculation. For example, the WTRU may determine one beam group for transmission in front of a vehicle and another beam group for transmission behind the vehicle. The CBR calculation for this beam group may be determined by the sensing results of one or any combination of multiple beams in the group.

[0194] If the WTRU has a packet for transmission, it can determine which CBR to use based on the attributes of the packet, which may include one or any combination of the following: the QoS requirements of the packet, such as the packet's priority, reliability, range, and delay budget; the type of packet transmission: unicast, multicast, or broadcast; or the intended transmission direction that may be indicated to the WTRU from upper layers / application layers.

[0195] For example, if the WTRU has a high priority unicast packet and a unicast link has been established between two WTRUs, the WTRU may use the CBR associated with the unicast beam(s) and the resource group format for symbol-based transmission. In another example, if the WTRU has a low priority broadcast packet, it may use the CBR associated with the beam group for beam scanning and the resource group format for slot-based transmission.

[0196] In some embodiments, the WTRU uses different thresholds for different types of timeslots to determine the availability of subchannels in a timeslot. For example, in some implementations, the WTRU may be configured to use different S-RSSI thresholds to determine the availability of subchannels in a timeslot based on the type of timeslot used for sidelink transmissions. In some implementations, the WTRU may use different S-RSSIs for timeslots with PSFCH resources, timeslots shared with the Uu interface, and / or timeslots where all symbols are used for PSSCH and / or PSCCH transmissions.

[0197] In some embodiments, the WTRU may be configured to use one S-RSS threshold per symbol per subchannel. In some such cases, the WTRU may determine the S-RSSI threshold for the subchannels in a timeslot by multiplying the per-symbol threshold for each subchannel by the number of symbols configured for PSSCH and / or PSCCH transmission.

[0198] In some implementations, the WTRU calculates the CBR based on different types of time slots. For example, in some implementations, the WTRU may calculate the CBR based on the following formula:

[0199]

[0200] in:

[0201] -i indicates each subchannel-timeslot index (which indicates one subchannel in one time slot) of the CBR calculation window.

[0202] -n i Indicates the number of symbols configured for PSSCH and / or PSCCH transmission.

[0203] - S-RSSI(i) indicates the measured S-RSSI in sub-channel-time slot i.

[0204] -S-RSSI 阈值 (i) indicates the critical value used to determine the availability of subchannel-time slot i

[0205] -δ(I) is an incremental function which takes the value 1 if I is true and the value 0 if I is false.

[0206] In some embodiments, the WTRU calculates one or more CBRs, each CBR for unicast, multicast and / or broadcast transmissions. For example, in some implementations, the WTRU may be configured to calculate different CBRs for different (e.g., unicast, multicast and / or broadcast) transmissions. In some implementations, the WTRU may use different S-RSSI thresholds and / or different sets of symbols within a time slot for measurement to determine the availability of subchannels in a time slot for unicast / multicast and broadcast. Such a method may be implemented for situations where unicast / multicast and broadcast use different sets of symbols in a time slot for PSSCH and / or PSCCH transmissions. For example, for broadcast, the WTRU may monitor the entire time slot to determine the S-RSSI, for example, because the broadcast transmission may use the entire time slot. For unicast / multicast, the WTRU may monitor earlier symbols in the time slot, but may not monitor later symbols in the time slot to determine the S-RSSI, for example, because these symbols may be used for PSFCH transmissions.

[0207] In some embodiments, the WTRU may be configured to calculate multiple CBRs for unicast, multicast, and / or broadcast in a resource pool based on the resources configured for each cast type. Figure 2 is a diagram of a resource pool configuration showing a resource pool configuration 200 for V2X channel resources. In this example, resources are shown on the vertical axis by subchannel (or group of subchannels) and on the horizontal axis by time. In configuration 200, resource pool 210 is reserved for broadcast transmissions only, resource pool 220 is reserved for unicast, multicast, and broadcast transmissions; and resource 230 is reserved for HARQ ACK / NACK. In this example, the WTRU calculates the CBR for unicast and multicast with resources in resource pool 220 because for unicast traffic, the WTRU is only allowed to use resources in resource pool 220. In addition, since broadcast traffic can use resources in resource pool 220 and resource pool 210, the WTRU calculates the CBR for broadcast with resources in resource pool 220 and resource pool 210.

[0208] In some examples, the WTRU may calculate multiple CBRs for data / control and HARQ ACK / NACK resources. This is also determined by Figure 2 As shown, for example, in one resource pool, the WTRU may calculate one CBR for PSSCH and PSCCH and one CBR for HARQ ACK / NACK resources. This approach may be implemented for situations where the occupancy of PSSCH / PSCCH is different from the occupancy of HARQ ACK / NACK resources. Based on the calculated CBR for HARQ ACK / NACK resources, the WTRU may determine to enable or disable HARQ feedback and / or change the resource pool configuration accordingly.

[0209] In some implementations, the WTRU calculates the CBR for the HARQ ACK / NACK. For example, the CBR for the HARQ ACK / NACK resources (CBR _HARQ ) may be calculated as a fraction of the total number of subchannel-symbols (one or more) allocated to the PSFCH divided by the total number of occupied subchannel-symbols (one or more) allocated to the PSFCH. The WTRU may consider a PSFCH resource to be occupied if the RSSI of the resource is greater than a threshold and / or the WTRU detects or determines that the PSSCH and / or PSCCH resources associated with the PSFCH resource are occupied.

[0210] Some embodiments include methods, devices, and systems for determining CR and CR_limit. To determine the CR, the WTRU may calculate the CR of the WTRU for each priority level. The WTRU may use multiple resource group formats to transmit packets with the same priority. For each priority level, the WTRU may use a resource group format to calculate the CR. The WTRU may use a resource group format to calculate the CR for more than one priority level. In order to determine the CR_limit to control the WTRU so that it does not over-utilize the channel, the WTRU may be constrained so that the CR of the packets of each priority level does not exceed a certain threshold.

[0211] Some embodiments include methods, devices, and systems for adaptation of transmission behavior and / or configuration. In some embodiments, the WTRU may be configured to change, for example, a threshold for a reliability mechanism based on CBR to enable different forms of reliability transmission (e.g., packet duplication, retransmission, etc.) if one or more congestion control parameters are greater than a threshold. The WTRU may be configured to perform reliable transmission when the reliability of the packet is above a threshold. The WTRU may be configured to use a higher threshold to achieve reliable transmission when one or more congestion control parameters are greater than a threshold. In some embodiments, the WTRU may be configured to replicate packets with reliability values ​​below a certain threshold (e.g., ≤4) when the CBR or CR is sufficiently low. However, if the CBR or CR is greater than a threshold, the WTRU may be configured to replicate packets with reliability values ​​below a lower threshold (e.g., ≤2). For example, a reliability value for a packet may be derived from a VQI. When the CBR or CR is greater than a threshold, the WTRU may disable reliable transmission. This approach may be motivated to reduce the number of packets generated when the medium is congested.

[0212] In some embodiments, the WTRU may determine to change the resource group format (RGF) transmission to meet the channel occupancy requirements. In this method, the WTRU may calculate multiple values ​​of CR and / or CBR, each of which may correspond to an RGF transmission. The WTRU may determine to change from one RGF transmission to another RGF transmission with a lower CR and / or CBR. For example, in a resource pool, the WTRU may be allowed to transmit slot-based transmissions and non-slot-based transmissions. The WTRU may be semi-statically configured or pre-configured to perform slot-based transmissions. If the WTRU determines that the CBR and / or CR for slot-based transmissions is greater than a threshold, the WTRU may change to non-slot-based transmissions to meet the channel occupancy requirements.

[0213] In some embodiments, the WTRU may determine to change the BWP based on one or more congestion control parameters (e.g., CBR and CR). In some embodiments, the WTRU may be configured or pre-configured with multiple SL BWPs. Based on the value of the congestion control parameter, the WTRU may change the BWP to use a less congested BWP.

[0214] In some embodiments, the WTRU may determine to change the resource pool based on one or more congestion control parameters (e.g., CBR and CR). In some embodiments, the WTRU may be configured or preconfigured with multiple resource pools. Based on the value of the congestion control parameter, the WTRU may determine to use a specific resource pool. This approach may be motivated by the need of the system to address congestion scenarios by allocating more resources to the system. In some embodiments, when the CBR is greater than a threshold, the WTRU may be configured or preconfigured to change to a larger resource pool or a resource pool with more transmission time. In some embodiments, the WTRU may be configured or preconfigured to use different resource pools for each CBR range.

[0215] In some embodiments, the WTRU may be configured to use different region configurations corresponding to different parameters, such as length, width, number of regions in length, and number of regions in width (L, W, N). X 、N Y ). Similar to LTE, a region may consist of a geographic area where the WTRU is allowed to use a specific resource pool. In some embodiments, the WTRU may be configured to use a maximum transmit power based on one or more congestion control parameters. The examples herein are described with respect to rectangular region definitions in LTE; however, note that the approach may generally be applied to regions of any shape (e.g., hexagonal regions, etc.). In some embodiments, the number of vehicles sharing the same resource pool may be adjusted in different congestion situations. For example, depending on the network configuration, adjustments may be made in the following options.

[0216] In a first option, in higher congestion situations (e.g., with congestion above a threshold), the WTRU reduces the region size (e.g., length and / or width). This may have the effect of increasing the spatial density of the regions; that is, so that there are more regions (e.g., N X and N YIn a second option, in a lower congestion scenario (e.g., with congestion below a threshold or reduced), the WTRU increases the region size, or returns the region to its original size (e.g., before the size reduction as described above). As an alternative to the first and second options, the network may configure resource pools that are only used for high congestion (e.g., with congestion above a threshold) scenarios. The resource pools may be configured such that additional resource pools are replenished in the region grid to avoid more congestion than in lower threshold (e.g., congestion below a threshold) instances (i.e., where N X and N Y was changed) to repeat the region more frequently.

[0217] For example, a WTRU may be configured with two different region size configurations, such as (L, W, N X , N Y ). In this example, if the measured CBR is below the configured threshold, the WTRU uses the first configuration, and when the measured CBR is above the configured threshold, the WTRU uses the second configuration. In some embodiments, the second configuration may specify that each area in the first configuration is further divided into multiple areas.

[0218] Figure 3 3 is a block diagram showing two example zone configurations 300, 310. A WTRU 350 is configured with the zone configurations 300 and 310, and CBR thresholds CBRThreshold1 and CBRThreshold2. In this example, the zone configuration specifies a rectangular zone with a zone length L, a zone width W, a number of zones N in the x-direction, and a X , the number of regions in the Y direction N Y and the maximum transmit power Pmax of the WTRU. In this example, the area configuration 300 has L=L1, W=W1, N X =2, N Y =2 and Pmax=A. The area configuration 310 has L=L2, W=W2, N X =4, N Y =4 and Pmax=0.5A.

[0219] exist Figure 3 In the example shown, the WTRU 350 may be configured to use the region configuration 300 when the CBR is low (i.e., below CBR threshold 2 in this example). However, when the CBR is greater than a certain threshold (i.e., CBR threshold 1 in this example), the WTRU is configured to use the configuration 310. In this example, upon transitioning from configuration 300 to configuration 310, Pmax is reduced in proportion to the amount of region size reduction (e.g., Pmax / 2 in this example) to determine its region ID and corresponding maximum transmit power.

[0220] In some embodiments, the WTRU may change its maximum power together with (e.g., simultaneously with) the area configuration based on a change in the congestion metric. In some embodiments, the WTRU may configure its maximum transmit power based on CBR and PPPP (e.g., according to an LTE-based method for configuring the WTRU maximum transmit power). In some embodiments, if the WTRU changes from one area size configuration to another area size configuration, the maximum power may change (e.g., in addition to the change based on CBR / PPPP) by a configured or preconfigured amount. For example, if the WTRU changes from one area size configuration to another area size configuration, the WTRU may increase or decrease the maximum transmit power by a configured amount.

[0221] In some examples, the WTRU may apply such an increase and / or decrease in maximum transmit power if the QoS requirements of the packets to be transmitted meet one or more configured, preconfigured, defined, or predefined conditions. Example conditions may include: if the WTRU's transmission is a high priority transmission, then the WTRU does not reduce its transmit power when changing the region size configuration.

[0222] In some examples, the WTRU may apply this increase and / or decrease in maximum transmit power if the WTRU is provided with additional areas to be added to the grid in the event of a decrease in area size. Example conditions may include: if the change includes L and W (but not N X and N Y ), the WTRU may change its transmit power when the region size configuration changes (assuming a rectangular region).

[0223] Figure 4 4 is a flow chart illustrating an example method 400 for a WTRU to select a region configuration based on a congestion level of a transmission medium. In step 410, the WTRU is configured to have two region configurations. The first region configuration corresponds to a larger region size (e.g., Figure 3 The region configuration 300 shown and described above) and the second region configuration corresponds to a smaller region size (e.g., as described with respect to Figure 3 Each configuration (or region size) is associated with a Pmax. In step 420, the WTRU is configured with a resource pool based on its current region ID.

[0224] In step 440, when the transmission medium represented by the resource pool is not congested 430 (for example, the CBR threshold is greater than a given threshold (for example, threshold 1)), the WTRU configures an area configuration corresponding to a larger area size; in step 450, when the transmission medium represented by the resource pool is congested 430 (for example, the CBR threshold is greater than a given threshold (for example, threshold 2, which may be the same as or different from threshold 1)), the WTRU configures an area configuration corresponding to a smaller area size; in step 460, in either case, the WTRU calculates a new area ID based on its location and the selected area size, configures Pmax associated with the area size, and configures the resource pool based on its area ID and the selected area.

[0225] For convenience and ease of description, Figure 4 Only two region configurations are described in the example of ; however, note that any suitable number of region configurations are possible, each with a corresponding selection condition.

[0226] In some embodiments, the WTRU may use any or a combination of congestion-related metrics (e.g., comparison with a threshold) as a trigger for changing its region size configuration (e.g., as described above, such metrics may include: a CBR measured by the WTRU (e.g., similar to LTE measurements); a ratio of occupied resources measured by decoding SCIs transmitted by other WTRUs; a number of messages received within a predefined / configured time; a number of different WTRUs from which the WTRU receives messages within a predefined / configured time; and / or a CBR measurement sent by another WTRU).

[0227] In some examples, the WTRU may be configured to transmit its CBR measurement periodically or if the WTRU is triggered by a CBR-related trigger (e.g., if its measured CBR is above / below a threshold, or changes by a certain amount). In some examples, the WTRU may transmit its CBR in an SCI transmission with or without data, in a SL synchronization signal or SL-MIB, in a SL-RRC message, and / or in a SL MAC CE. For example, the WTRU may calculate an average (e.g., weighted average) CBR measurement as the average of its own measured CBR and the CBR received from neighboring WTRUs.

[0228] In some embodiments, a WTRU may use an area configuration received from another WTRU to trigger its own area size configuration change. In some embodiments, a WTRU may be configured with a set of pools to be used for each area ID (e.g., one pool per area ID). The set may be configured by the WTRU based on the configured area size parameters (e.g., L, W, N X 、N Y). In some examples, the WTRU may use the same pool set regardless of the value of the region size parameter it uses (e.g., derived from CBR). In some embodiments, the WTRU may be configured with two or more pool sets and may use one pool set when it uses a first region size configuration (e.g., low congestion scenario, such as congestion below a threshold) and may use a second pool set when it uses a second region size configuration (e.g., high congestion scenario, such as congestion above a threshold). The second region may have a region parameter that is proportional to the first region.

[0229] Some embodiments are directed to conflicting area configurations for neighboring WTRUs. In some cases, two UEs within range of each other may measure different CBRs and may each use a different area configuration (e.g., one using a high CBR range configuration and the other using a low CBR range configuration). In some cases, this may result in neighboring WTRUs using the same area ID in an adjacent area, with one WTRU transmitting at a reduced or lower power and the other WTRU transmitting at a higher power.

[0230] In some embodiments, in order to resolve conflicting zone configurations for neighboring WTRUs, the WTRU may change its resource selection or reselection behavior based on the zone configuration state. For example, based on the zone configuration state (e.g., L, W, N X 、N Y Depending on the specific configuration of the WTRU, the WTRU may use different resource reselection criteria, different resource availability and / or occupancy criteria, different access or sensing mechanisms, or different resource selection mechanisms.

[0231] For example, to resolve conflicting regional configurations for neighboring WTRUs, the WTRU may be configured with different resource selection criteria depending on the regional configuration state. For example, the WTRU may be configured with a number of consecutive periodic resources that may be reserved before performing a reselection, where the number may depend on the regional configuration state. For example, a WTRU configured with a smaller region and a smaller transmit power may be allowed a smaller consecutive number of periodic resources (e.g., a smaller initial value of SL_RESOURCE_RESELECTION_COUNTER) before having to perform resource selection. In some cases, this may have the advantage of facilitating detection of transmissions from a WTRU with a conflicting regional configuration state, where the WTRU may be transmitting at a higher power.

[0232] In some examples, to resolve conflicting region configurations for neighboring WTRUs, the WTRU may be configured with different criteria for determining resource availability and / or occupancy, such as those derived from sensing results. For example, the WTRU may be configured with thresholds (e.g., RSRP, RSSI, etc.) for determining resource occupancy and / or availability based on sensing results, where the thresholds may depend on the region configuration state. For example, a WTRU using a larger region size may be configured with a lower threshold for PSSCH / PSCCH when determining resource occupancy during resource selection.

[0233] In some examples, to resolve conflicting region configurations for neighboring WTRUs, the WTRU may change its sensing mechanism, or change aspects related to its sensing algorithm. For example, the WTRU may use different sensing modes (e.g., LBT vs. (vs.) SCI sensing) depending on the region size configuration state, assuming that the WTRU can operate in multiple sensing modes; the WTRU may use different parameters related to sensing (e.g., different occupancy thresholds); and / or the WTRU may use different sensing windows for sensing results depending on the region configuration state.

[0234] In some examples, in order to resolve conflicting regional configurations for neighboring WTRUs, the WTRU may change the resource selection mechanism based on the regional configuration state. For example, the WTRU may select different numbers, types and / or resource sets. For example, the WTRU may perform resource selection using different types of resources, for example, the WTRU may perform mode selection for a specific regional configuration state and perform separate resource selection for another regional configuration state, etc. In another example, the WTRU may select from different resource sets or mode sets depending on the regional configuration state. In another example, the WTRU may use different access times depending on the regional configuration state.

[0235] In some embodiments, the WTRU may change its resource selection or reselection behavior based on the regional configuration state by modifying its resource selection or reselection behavior based on its regional configuration state. For example, the WTRU may modify its resource selection or reselection behavior based on the WTRU determining that a neighboring WTRU is using a different regional configuration (e.g., with a higher priority). In some examples, the WTRU may make this determination based on receipt of the CBR or regional configuration state of other WTRUs (e.g., as described herein); the WTRU may modify its resource selection or reselection behavior based on its speed being above a certain threshold; and / or the WTRU may modify its resource selection or reselection behavior based on the QoS of the WTRU's transmissions satisfying some configuration or preconfigured conditions (e.g., the WTRU may modify the reselection resource selection or reselection behavior only when it has a high priority transmission, etc.).

[0236] In some embodiments, in order to resolve conflicting region configurations for neighboring WTRUs, the WTRU may transmit its region size configuration to other WTRUs on the sidelink. For example, the WTRU may transmit the region size configuration in: an SCI transmission on the PSCCH (e.g., associated with an indication of a data transmission); in a MAC CE (e.g., transmitted on the PSSCH); on a SL broadcast channel or SL feedback channel (e.g., SL-MIB or PSFCH); and / or in a SL-RRC message. In some embodiments, the WTRU may transmit its region size configuration periodically. In some implementations, the WTRU may transmit its region size configuration after an event occurs, such as an event related to a change in the CBR; a change in the region size configuration used by the WTRU or detected by another WTRU; and / or a change in the position or speed of the WTRU.

[0237] In some embodiments, the WTRU may further transmit a priority along with (e.g., simultaneously with) its region size configuration. Such a priority may be derived from the measured CBR. In some embodiments, the WTRU may be configured or pre-configured with a mapping of CBR ranges to priorities, or the priority may be implicit in the region size configuration itself. For example, a region size configuration corresponding to a smaller region size may have a higher priority than a region size configuration having a larger region size.

[0238] In some embodiments, in order to resolve conflicting area configurations for neighboring WTRUs, a WTRU may change its area size configuration after receiving an area size configuration of another WTRU. For example, a WTRU may change its area size configuration to match the area size configuration of another WTRU (e.g., the WTRU from which it received the area size). In some embodiments, a WTRU may match its area size configuration with the area size configuration of another WTRU if the other WTRU is the intended recipient of the WTRU; the other WTRU is within the transmission range or transmission direction of the WTRU (e.g., based on the WTRU's own transmission direction or transmission range); the majority of received area size configurations received from the other WTRU are different from the WTRU's own area size configuration; and / or the area size configuration of the other WTRU has a higher priority than the WTRU's own area size configuration (e.g., implicitly or based on an explicit indication, as described herein).

[0239] In some embodiments, the WTRU may be configured to change the scheduling mode when one or more congestion control parameters are greater than or less than a threshold. In some embodiments, if one or more congestion control parameters or a combination thereof (e.g., CBR / CR) are greater than a threshold, the WTRU may determine to switch from an autonomous scheduling mode to a network scheduling mode. This method may help the system reduce the CBR of the autonomous scheduling resource pool, and since the network may have better capacity when handling congested scenarios, this method may facilitate the network's service to the WTRU. In such an embodiment, a WTRU operating in an autonomous scheduling mode may be configured to report the congestion level of a channel before and / or after requesting a change in scheduling mode. Based on the reported CBR and its load, the network may determine to accept or reject the request to change the scheduling mode.

[0240] In some embodiments, the WTRU may decide to enable / disable pool sharing to perform congestion control based on the value of one or more congestion control parameters. The WTRU may be configured to change from pool sharing to non-pool sharing when the CBR or CR is greater than a threshold. This approach may be motivated by situations where congestion control can be managed more effectively in non-pool sharing situations. In some embodiments, the WTRU may change its resource mode configuration based on one or more congestion control parameters. For example, in some embodiments, such as associated with resource selection based on a transmission mode, the WTRU may change the mode configuration based on the congestion control parameters. In some examples, the WTRU may change one or more of the following mode configurations: mode window and / or usage mode set.

[0241] In some embodiments, the WTRU may change the duration of the pattern window based on the congestion level of the resource pool. For example, the WTRU may be configured with a mapping between the pattern window and the congestion level of the resource pool. Then, based on the congestion level of the resource pool, the WTRU may select an appropriate pattern based on the mapping. For example, if the resource pool is congested, this method may be used to reduce the number of retransmissions for a TB resource. This method is applicable, for example, in some cases where the WTRU may need to transmit a TB within a pattern and the number of transmissions in a pattern is related to the duration of the pattern window.

[0242] In some embodiments, the WTRU changes the density of HARQ ACK / NACK feedback resources in the resource pool configuration. For example, in one method, the WTRU may be configured to use multiple resource pool configurations, where each configuration may include one or any combination of the following: periodicity of HARQ ACK / NACK resources, density of HARQ ACK / NACK resources in each period (i.e., number of HARQ ACK / NACK resources in each period), and / or resources for unicast, groupcast, and broadcast (e.g., time and frequency resources).

[0243] In some implementations, the WTRU may be configured to use different resource pool configurations for congestion control, such as based on the CBR of the resource pool. For example, if the CBR of the resource pool is within a predetermined range, the WTRU may be configured to use one resource pool configuration. In some examples, the WTRU may be configured to use a resource pool configuration with a relatively small number of HARQ ACK / NACK resources and / or a relatively large periodicity of HARQ ACK / NACK resources if the CBR of the resource pool is greater than a threshold, and to use a resource pool with a relatively large number of HARQ ACK / NACK resources and / or a relatively small periodicity of HARQ ACK / NACK resources if the CBR of the resource pool is less than a threshold. The CBR threshold used to determine which resource pool configuration to use may be (pre)configured or configured via RRC / SIB.

[0244] In some embodiments, the WTRU modifies the size and / or density of resource pools for unicast, multicast, and broadcast. For example, the WTRU may be configured to use different resource pools for unicast / multicast and broadcast. In some examples, the WTRU may be configured to reduce the size of the resource pool for unicast and / or multicast, and such resources previously used for unicast and / or multicast may also be used for broadcast transmission. In some examples, the WTRU may be configured to use different configurations of resource pools for unicast / multicast and broadcast for a specific range of CBR. In some examples, based on the measured CBR, the WTRU may decide which resource pool configuration to use accordingly. In some embodiments, for a side link, unicast, or multicast, a WTRU that changes its resource pool configuration based on its CBR measurement may need to notify other WTRUs in the same unicast or multicast session, for example, so that they communicate based on the same resource pool configuration. In some examples, the WTRU may send a notification signal to other (i.e., peer) WTRUs in the same unicast or multicast session, which notification signal may be in the form of a CBR measurement, or in the form of a direct indication of the pool configuration. Peer WTRUs in the same unicast or multicast session may be configured to change to another resource pool configuration based on information such as the CBR and / or the pool configuration of the peer unicast or multicast WTRU.

[0245] Figure 5 5 is a diagram of a resource pool configuration showing resource pool configurations 500 and 550 for V2X channel resources. In this example, resources are shown on the vertical axis by subchannel (or group of subchannels) and on the horizontal axis by time. In configurations 500 and 550, resource pool 510 is reserved for broadcast, resource pool 520 is reserved for multicast, resource pool 530 is reserved for unicast, and resource 540 is reserved for HARQ ACK / NACK. Figure 5, if the CBR is less than the currently configured threshold (i.e., CBR>CBRThreshold1 in this example), the WTRU uses a resource pool configuration 500 where the number of subchannels used for broadcast, multicast, and unicast are equal. However, if the CBR is greater than the currently configured threshold (i.e., CBR>CBRThreshold2 in this example), the WTRU uses a resource pool configuration 550 where the number of subchannels used for unicast and multicast is halved, while the number of subchannels used for broadcast is doubled. Note that halving and doubling are merely exemplary, and any suitable permutation may be used in other implementations.

[0246] In some embodiments, if the CBR of the resource pool is greater than a threshold, the WTRU may decide to stop unicast and / or multicast transmissions. For example, if the CBR of the resource pool is greater than a threshold, the WTRU may be configured to terminate one or any combination of the following transmissions: a set of unicast links, all unicast links, a set of multicast transmissions, and / or all multicast transmissions. For example, such a method may be implemented to prioritize broadcast transmissions over unicast and multicast transmissions.

[0247] Some embodiments include methods, devices, and systems for resource selection. In various resource selection methods, it may be assumed that the WTRU has data available for transmission at its buffer. The WTRU may determine a set of available resources for its transmission that meets the QoS requirements of the data. The WTRU may then select resources within the set of available resources for transmitting one or more TBs. Some embodiments include methods, devices, and systems for dynamic resource selection. In some embodiments, the WTRU may determine a beam scanning mode based on CBR, CR, or both CBR and CR. The WTRU may be configured to select a maximum number of beam transmissions per packet. The WTRU may select the actual number of beam transmissions based on its CR. The WTRU may select the number of beam transmissions to meet the CR requirement.

[0248] The WTRU may be configured with a certain number of beam scanning configurations for transmitting a packet to cover a spatial region. Based on the current CR, the WTRU may select a specific beam scanning configuration. Each beam scanning configuration may indicate X beams to be scanned, each beam may be repeated Y times, and Y may be different for each beam.

[0249] Figure 6 is a block diagram showing an example of resource selection for different beam scanning modes. Figure 6 In the example shown, the WTRU 600 is configured with four beam scanning pattern configurations (Configuration 1, Configuration 2, Configuration 3, and Configuration 4) for different ranges of CBR values.

[0250] If the CBR is below a first given threshold (in this example, CBR ≤ CBR1), the WTRU selects transmission resources using configuration 1 and accordingly selects 12 resources for transmitting one TB. The WTRU uses 6 antenna beams 605, 610, 615, 620, 625, 630 to cover the entire spatial region around the WTRU 600. Of the 12 selected resources, 6 resources 606, 611, 616, 621, 626, 631 are used for transmission on antenna beams 605, 610, 615, 620, 625, 630, respectively, while resources 606, 612, 617, 622, 627, and 632 are used for retransmission on antenna beams 605, 610, 615, 620, 625, 630, respectively.

[0251] If the CBR is above a first given threshold, but below a second given threshold (in this example, CBR1≤CBR≤CBR2), the WTRU uses configuration 2 to select transmission resources and accordingly selects resources 606, 611, 616, 621, 626, 631 (or another 6 suitable resources) to transmit one TB on antenna beams 605, 610, 615, 620, 625, 630, respectively. No resources are selected for retransmission in configuration 2. If the CBR is above a second given threshold, but below a third given threshold (in this example, CBR2≤CBR≤CBR3), the WTRU uses configuration 3 to select transmission resources and accordingly selects two resources 621 and 631 for one TB transmission on antenna beam 650 covering the front of the WTRU and antenna beam 660 covering the rear of the WTRU, respectively. If the CBR is above a third given threshold (in this example, CBR>CBR3), the WTRU selects one resource 621 for one TB transmission on antenna beam 670. Antenna beam 670 is an omni-directional beam that covers the entire spatial region around WTRU 600 .

[0252] In some embodiments, the WTRU selects the number of TBs to be transmitted for a packet based on the CBR, the CR, or both the CBR and the CR. For example, the WTRU may be configured to perform resource selection for the transmission of N TBs. The WTRU may be notified from a higher layer that these TBs may originate from a packet in a higher layer. In order to ensure the CR limit, the WTRU may select resources for transmitting some TBs and discard the remaining TBs. Alternatively, the WTRU may determine to discard all N TBs. The WTRU may reduce the number of subchannels used for each TB transmission by increasing the MCS. In some embodiments, if the attributes of the packet are similar to the attributes of a video sharing packet, the receiving WTRU is able to reconstruct the video information if some TBs are lost. In some embodiments, if the attributes of the packet are similar to the attributes of a file transfer protocol (FTP) file sharing packet, the receiving WTRU may not be able to recover the information if one TB is lost. Therefore, the WTRU's choice to discard all or some TBs may depend on the type of packet.

[0253] Figure 7 700 shows a scenario where the CBR is less than a given threshold (in this example, CBR < CBR Threshold). In this case, the WTRU selects N resources for transmission of N TBs. Resource diagram 750 shows a different scenario where the CBR is greater than a given threshold (in this example, CBR > CBR Threshold). In this case, the WTRU selects K < N resources to transmit the packet and also reduces the resource size for each transmission in TBs 1-K (in this example by reducing the number of subchannels used for transmission).

[0254] In some embodiments, the WTRU determines the number of sidelink processes based on the CBR. In some embodiments, the WTRU may be configured to change the resource selection criteria for multiple TB transmissions; for example, if the transmission is split into large packets of multiple TBs, a greater or lesser number of sidelink processes are used. If the congestion control parameter is small, the WTRU may be configured to perform resource selection using a single sidelink process (e.g., using continuous transmissions of multiple TBs). The WTRU may be configured to perform resource selection using multiple sidelink processes for each TB, and if the CBR is greater than a threshold, these transmissions may be dispersed in the frequency domain and discontinuous in the time domain.

[0255] Some embodiments include methods, devices, and systems for forward reservation resource selection. In some embodiments, the WTRU determines a packet drop pattern based on traffic characteristics and / or beam transmission mode. In some embodiments, the WTRU may determine a drop pattern based on one or more congestion control parameters, priority and / or periodicity of packets, and / or beam transmission mode. In some embodiments, the WTRU applies a specific probability that it may drop packets, for example based on traffic characteristics or beam transmission mode. In some embodiments, the WTRU may deterministically drop N packets from M (M≥N) packets during a resource reservation interval.

[0256] Figure 8 is a signal diagram showing a packet drop pattern for different priority resource reservations. The signal diagram shows a first example packet drop pattern for high priority packets 800, 805, 810, 815, 820, 825, wherein one of every two high priority packets (i.e., packets 805, 815, 825) in the resource reservation interval is dropped (i.e., deterministically). Different implementations using a probabilistic loss rate of 60% will approximate this pattern.

[0257] The signal diagram also shows a second example packet drop pattern for intermediate priority packets 830, 835, 840, 845, 850, 855, 860, 865, 870, 875, where four of every five intermediate priority packets (i.e., packets 835, 840, 845, 850, 860, 865, 870, 875) in the resource reservation interval are dropped (i.e., deterministically). Different implementations using a probabilistic loss rate of 80% will approximate this pattern. The signal diagram also shows a third example packet drop pattern for low priority packets 880, 885, 890, 895, 897, where all low priority packets 880, 885, 890, 895, 897 in the resource reservation interval are dropped (i.e., deterministically). Different implementations using a probabilistic loss rate of 100% will approximate this pattern.

[0258] Fig. 9 is a flow chart illustrating an example method for zone configuration implemented in a WTRU. In step 910, the WTRU receives a zone configuration (e.g., Figure 3 In step 920, the WTRU receives the CBR threshold for each area configuration received in step 910. In step 930, the WTRU receives a mapping of area IDs to resource pools for each area configuration received in step 910. Each area of ​​each area configuration corresponds to an area ID and a resource pool. In step 940, the WTRU measures the CBR of its current resource pool to determine congestion of the transmission medium.

[0259] Under condition 950 that the CBR does not satisfy the CBR threshold for any of the area configurations received in step 920, the WTRU returns to step 940 and continues to measure the CBR. Otherwise, under condition 950 that the CBR satisfies the CBR threshold for one of the area configurations received in step 920, the WTRU configures an area configuration corresponding to the CBR threshold in step 960, configures an area ID based on the new area configuration and its location in step 970, and configures a resource pool based on the mapping received in step 930 and the configured area ID in step 970. The WTRU then returns to step 940 and continues to measure the CBR.

[0260] In some embodiments, the WTRU may adjust the probability of retaining resources based on congestion control parameters. For example, if the CR of the WTRU is high enough, the WTRU may decide not to retain resources after the reservation window. In some embodiments, the WTRU may adjust the reservation window based on congestion control parameters and / or the priority of the packet. For example, if the CR and / or CBR are high enough, the WTRU may decide to perform dynamic resource selection for periodic services to ensure channel occupancy requirements. In some embodiments, the WTRU may first reduce the probability of retaining resources to zero. If this adjustment is not sufficient to meet the channel occupancy requirements of the system, the WTRU may further reduce the reservation window for periodic services.

[0261] Although the features and elements are described above in specific combinations, it will be understood by those skilled in the art that each feature or element can be used alone or in any combination with other features and elements. In addition, the methods described herein can be implemented in a computer program, software, or firmware, which is incorporated into a computer-readable medium to be executed by a computer or processor. Examples of computer-readable media include electronic signals (transmitted via a wired or wireless connection) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, read-only memory (ROM), random access memory (RAM), registers, cache memory, semiconductor memory devices, magnetic media such as internal hard disks and abnormal disks, magneto-optical media, and optical media such as CD-ROM disks and digital versatile disks (DVDs). A processor associated with the software can be used to implement a radio frequency transceiver used in a WTRU, UE, terminal, base station, RNC, or any host computer.

Claims

1. A method implemented in a wireless transmit / receive unit (WTRU), the method comprising: Receive multiple zone configurations; receiving, for each of the plurality of zone configurations, a channel busy rate (CBR) threshold and a mapping of a zone identification (ID) to a resource pool; measuring the CBR of the resource pool with which the WTRU is currently configured; On the condition that the measured CBR satisfies a CBR threshold corresponding to a first area configuration among the plurality of area configurations: configuring the WTRU with the first region configuration, configuring an area ID for the WTRU based on the first area configuration and the location of the WTRU, and A resource pool is configured for the WTRU based on the mapping and the configured area ID.

2. The method of claim 1 , wherein each of the plurality of area configurations indicates a maximum transmit power (Pmax) value for the WTRU.

3. The method of claim 1 , further comprising receiving a maximum transmit power (Pmax) value for the WTRU for each of the plurality of area configurations.

4. The method according to claim 1, further comprising, under the condition that the measured CBR satisfies the CBR threshold configured for the first area: Based on the first area configuration, a maximum transmit power (Pmax) value is configured for the WTRU. The method of claim 1 , wherein each of the plurality of region configurations indicates a region size. The method of claim 1 , wherein each of the plurality of region configurations comprises a region size parameter. The method of claim 1 , wherein each of the plurality of zone configurations indicates a zone dimension of the zone configuration.

8. The method of claim 1, wherein each of the plurality of region configurations indicates a region length (L) and a region width (W) of the region configuration. 9 . The method of claim 1 , wherein each of the plurality of area configurations indicates a number of area IDs of the area configuration.

10. The method of claim 1, wherein each of the plurality of region configurations indicates a length (N X ) and the width (N Y ) is the number of regions on .

11. A wireless transmit / receive unit (WTRU), the WTRU comprising: a transceiver configured to receive a plurality of zone configurations; a transceiver configured to receive, for each of the plurality of zone configurations, a channel busy rate (CBR) threshold and a mapping of a zone identification (ID) to a resource pool; a processor coupled to the transceiver and configured to measure a CBR of a resource pool with which the WTRU is currently configured; The processor is further configured to, on the condition that the measured CBR satisfies a CBR threshold corresponding to a first area configuration of the plurality of area configurations: configuring the WTRU with the first region configuration, configuring an area ID for the WTRU based on the first area configuration and the location of the WTRU, and A resource pool is configured for the WTRU based on the mapping and the configured area ID.

12. The WTRU of claim 11, wherein each of the plurality of area configurations indicates a maximum transmit power (Pmax) value for the WTRU.

13. The WTRU of claim 11, wherein the transceiver is further configured to receive a maximum transmit power (Pmax) value for the WTRU for each of the plurality of zone configurations.

14. The WTRU of claim 11 , wherein the processor is further configured to, on the condition that the measured CBR satisfies the CBR threshold configured for the first area: Based on the first area configuration, a maximum transmit power (Pmax) value is configured for the WTRU.

15. The WTRU of claim 11, wherein each of the plurality of area configurations indicates an area size.

16. The WTRU of claim 11, wherein each of the plurality of area configurations comprises an area size parameter.

17. The WTRU of claim 11, wherein each of the plurality of area configurations indicates an area dimension of the area configuration.

18. The WTRU of claim 11, wherein each of the plurality of area configurations indicates an area length (L) and an area width (W) of the area configuration.

19. The WTRU of claim 11, wherein each of the plurality of area configurations indicates a number of area IDs of the area configuration.

20. The WTRU of claim 11, wherein each of the plurality of area configurations indicates a length (N X ) and the width (N Y ) is the number of regions on .

Images