KR20240073918A - Hybrid Automatic Repeat Request (HARQ)-related approach to mitigate the effects of interference - Google Patents

Abstract

The method performed by the base station includes detecting an interference pattern; determining whether the interference pattern affects one or more code blocks (CB) within one or more code block groups (CBG); adjusting the size of one or more CBGs; and transmitting information associated with adjustment of the size of one or more CBGs to a wireless transmit/receive unit (WTRU). Interference patterns can be caused by radar (radio detection and ranging) systems. Adjusting the size of one or more CBGs may include increasing or decreasing the number of CBs within the one or more CBGs. Transmission of information regarding adjustment of the size of one or more CBGs may be performed via master information block (MIB) signaling, radio resource control (RRC) signaling, or downlink control information (DCI) signaling.

Description

Hybrid Automatic Repeat Request (HARQ)-related approach to mitigate the effects of interference

Cross-reference to related applications

This application claims the benefit of U.S. Provisional Application No. 63/249,889, filed September 29, 2021, and U.S. Provisional Application No. 63/391,497, filed July 22, 2022, the contents of which are incorporated herein by reference. incorporated by reference.

Automatic Repeat Request (ARQ) is an error control technique that relies on retransmission but discards incorrectly received data. This may lead to a decrease in ARQ efficiency. Hybrid ARQ (HARQ) utilizes these erroneous packets by storing them in a buffer memory and combining them to obtain the originally transmitted data. HARQ paired with a multiple stop-and-wait transmission protocol is a powerful error correction mechanism that does not limit throughput, as opposed to a single stop-and-wait protocol.

In recent communication systems, the need for asynchronous HARQ on both uplink and downlink has become paramount as it allows dynamic TDD as well as operation in unlicensed spectrum. Additionally, it is typical for cellular systems to support multiple HARQ processes. For example, LTE supports up to 8 multiple HARQ processes for FDD and up to 15 for TDD, while 5G New Radio supports up to 16 multiple HARQ processes.

A method performed by a wireless transmit/receive unit (WTRU) includes receiving, from a base station, first downlink control information (DCI) indicating a first code block group (CBG) size; Receiving, from a base station, a transport block (TB) comprising one or more CBGs, wherein the one or more CBGs comprise one or more code blocks (CBs); performing a cyclic redundancy check (CRC) on the received TB; Transmitting feedback based on the CRC to the base station; and receiving, from the base station, a second DCI indicating a second CBG size, wherein the second CBG size is based on the transmitted feedback. Feedback may be an acknowledgment (ACK) or a negative acknowledgment (NACK). If the feedback is ACK, the second CBG size may be larger than the first CBG size. If the feedback is NACK, the second CBG size may be smaller than the first CBG size.

The method performed by the base station includes detecting an interference pattern; determining whether an interference pattern affects one or more code CBs within the one or more CBGs; adjusting the size of one or more CBGs; and transmitting information associated with adjustment of the size of one or more CBGs to the WTRU. Interference patterns can be caused by radar (radio detection and ranging, or RADAR) systems. Adjusting the size of one or more CBGs may include increasing the number of CBs within the one or more CBGs. Adjusting the size of one or more CBGs may include reducing the number of CBs within the one or more CBGs. Interference patterns can affect the same CB instance in each CBG. The base station may detect interference patterns based on feedback from one or more WTRUs.

Transmitting information regarding adjustment of the size of one or more CBGs may be performed via master information block (MIB) signaling. Transmitting information regarding adjustment of the size of one or more CBGs may be performed via radio resource control (RRC) signaling. RRC signaling may include information indicating the CBG sizing duration. Transmitting information regarding adjustment of the size of one or more CBGs may be performed via downlink control information (DCI) signaling.

A more detailed understanding can be obtained from the following description given by way of example in conjunction with the accompanying drawings, in which like reference numerals within the drawings indicate like elements.
1A is a system diagram illustrating an example communications system in which one or more disclosed embodiments may be implemented.
FIG. 1B is a system diagram illustrating an example wireless transmit/receive unit (WTRU) that may be used within the communication system illustrated in FIG. 1A according to one embodiment.
FIG. 1C is a system diagram illustrating an example radio access network (RAN) and an example core network (CN) that may be used within the communication system illustrated in FIG. 1A according to one embodiment.
FIG. 1D is a system diagram illustrating an additional example RAN and an additional example CN that may be used within the communication system illustrated in FIG. 1A according to one embodiment.
Figure 2 is a diagram illustrating downlink retransmission of an example CBG.
3 is a diagram illustrating example PUSCH HARQ feedback timing.
4 is a diagram illustrating example PDSCH HARQ feedback timing.
5 is a diagram illustrating an example dynamic code block regrouping used to adjust the size of a transmitted CBG based on the presence of interference.
6 is a diagram illustrating example dynamic code block regrouping used to adjust the size of a transmitted CBG based on the presence of interference.
7 is a diagram illustrating example code block division, filler insertion, CRC insertion, and CB grouping.
8 is a diagram illustrating an example process of CBG sizing according to one embodiment.
9 is a diagram illustrating an example of RRC configuration CBG sizing.
Figure 10 is a diagram illustrating an example when interleaving is applied and all CBGs need to be retransmitted.
11 is a diagram illustrating an example when interleaving is applied and CBG #1 and CBG #3 are error-free and do not need to be retransmitted.
Figure 12 is a diagram illustrating an example process of CBG sizing according to one embodiment.

1A is a diagram illustrating an example communications system 100 in which one or more disclosed embodiments may be implemented. Communication system 100 may be a multiple access system that provides content such as voice, data, video, messaging, broadcast, etc. to multiple wireless users. Communication system 100 may enable multiple wireless users to access such content through sharing of system resources, including wireless bandwidth. For example, communication system 100 may include code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single-carrier FDMA (SC-FDMA), zero -One or more channels, such as tail unique-word Discrete Fourier Transform spreading OFDM (ZT-UW-DFT-S-OFDM), unique word OFDM (UW-OFDM), resource block-filtering OFDM, Filter Bank Multicarrier (FBMC), etc. Access methods are available.

As shown in FIG. 1A, communication system 100 includes wireless transmit/receive units (WTRUs) 102a, 102b, 102c, and 102d, a radio access network (RAN) 104, and a core network (CN) 106. , public switched telephone network (PSTN) 108, the Internet 110, and other networks 112, but the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and/or network elements. This will be understood. Each of the WTRUs 102a, 102b, 102c, and 102d is any type of device configured to operate and/or communicate in a wireless environment. By way of example, any of the WTRUs 102a, 102b, 102c, 102d, which may be referred to as a station (STA), may be configured to transmit and/or receive wireless signals and may be connected to a user equipment (UE), a mobile station, or a mobile station. , fixed or mobile subscriber units, subscription-based units, pagers, mobile phones, personal digital assistants (PDAs), smartphones, laptops, netbooks, personal computers, wireless sensors, hotspots or Mi- Fi devices, Internet of Things (IoT) devices, watches or other wearables, head-mounted displays (HMDs), vehicles, drones, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., and/or robots and/or other wireless devices operating in an automated processing chain environment), consumer electronic devices, devices operating in commercial and/or industrial wireless networks, etc. Any of the WTRUs 102a, 102b, 102c, and 102d may be referred to interchangeably as a UE.

Communication system 100 may also include base station 114a and/or base station 114b. Base stations 114a, 114b each have WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks, such as CN 106, Internet 110, and/or other networks 112. It may be any type of device configured to wirelessly interface with at least one of the following. As an example, base stations 114a and 114b may be configured to support a new radio, a next-generation NodeB such as a base transceiver station (BTS), a NodeB, an eNode B (eNB), a Home Node B, a Home eNode B, and a gNode B (gNB). (NR) Node B, site controller, access point (AP), wireless router, etc. Although base stations 114a and 114b are each shown as a single element, it will be appreciated that base stations 114a and 114b may include any number of interconnected base stations and/or network elements.

Base station 114a may also be part of RAN 104, which may include other base stations and/or network elements (not shown), such as base station controllers (BSCs), radio network controllers (RNCs), relay nodes, etc. . Base station 114a and/or base station 114b may be configured to transmit and/or receive wireless signals on one or more carrier frequencies, which may be referred to as cells (not shown). These frequencies may be within licensed spectrum, unlicensed spectrum, or a combination of licensed and unlicensed spectrum. Cells may provide coverage for wireless services over a specific geographic area, which may be relatively fixed or may change over time. Cells may be further divided into cell sectors. For example, the cell associated with base station 114a may be divided into three sectors. Accordingly, in one embodiment, base station 114a may include three transceivers, one for each sector of the cell. In an embodiment, base station 114a may employ multiple-input multiple-output (MIMO) technology and utilize 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.

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

More specifically, as mentioned above, 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, base stations 114a and WTRUs 102a, 102b, 102c of RAN 104 may establish air interfaces 116 using wideband CDMA (WCDMA), such as the Universal Mobile Telecommunications System (UMTS); Radio technologies such as Terrestrial Radio Access (UTRA) can be implemented. 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 uplink (UL) packet access (HSUPA).

In embodiments, base station 114a and WTRUs 102a, 102b, and 102c may utilize, for example, Long Term Evolution (LTE) and/or LTE-Advanced (LTE-A) and/or LTE-Advanced (LTE-A Pro). Pro) can be used to implement radio technologies such as Evolved UMTS Terrestrial Radio Access (E-UTRA) that can establish an air interface 116.

In embodiments, base station 114a and WTRUs 102a, 102b, and 102c may implement a radio technology, such as NR wireless access, that may establish air interface 116 using NR.

In embodiments, base station 114a and WTRUs 102a, 102b, and 102c may implement multiple radio access technologies. For example, base station 114a and WTRUs 102a, 102b, and 102c may implement LTE radio access and NR radio access together, for example, using dual connectivity (DC) principles. Accordingly, the air interfaces utilized by WTRUs 102a, 102b, and 102c feature transmissions to/from multiple types of radio access technologies and/or multiple types of base stations (e.g., eNBs and gNBs). You can do this.

In other embodiments, base station 114a and WTRUs 102a, 102b, 102c may support IEEE 802.11 (i.e., wireless fidelity (WiFi)), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile Communications (GSM), Enhanced Data Rates for GSM Evolution (EDGE) ), GSM EDGE (GERAN), etc. can be implemented.

Base station 114b in FIG. 1A may be, for example, a wireless router, Home Node B, Home eNode B, or access point and may be used in a business, home, vehicle, campus, industrial facility, airway (e.g., drone). Any suitable RAT may be utilized to facilitate wireless connectivity in localized areas, such as roads, roads, etc. In one embodiment, base station 114b and WTRUs 102c and 102d may implement radio technology, such as IEEE 802.11, to establish a wireless local area network (WLAN). In embodiments, base station 114b and WTRUs 102c and 102d may implement radio technology, such as IEEE 802.15, to establish a wireless personal area network (WPAN). In another embodiment, base station 114b and WTRUs 102c, 102d may use a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE) to establish a picocell or femtocell. -A, LTE-A Pro, NR, etc.) can be used. As shown in Figure 1A, base station 114b may be directly connected to the Internet 110. Accordingly, base station 114b may not need to access the Internet 110 via CN 106.

RAN 104 is a CN (CN), which can be any type of network configured to provide voice, data, applications, and/or voice over Internet Protocol (VoIP) services to one or more WTRUs 102a, 102b, 102c, 102d. 106). Data may have different quality of service (QoS) requirements, such as different throughput requirements, latency requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, etc. CN 106 may provide call control, billing services, mobile location-based services, prepaid calling, Internet connectivity, video distribution, etc. and/or perform high-level security functions, such as user authentication. Although not shown in FIG. 1A, it will be appreciated that RAN 104 and/or CN 106 may communicate directly or indirectly with another RAN employing the same RAT as RAN 104 or a different RAT. In addition to being connected to RAN 104, which may utilize NR radio technology, for example, CN 106 may also be connected to other RANs that employ GSM, UMTS, CDMA 2000, WiMAX, E-UTRA, or WiFi radio technology. (not shown) can be communicated with.

CN 106 may also serve as a gateway for WTRUs 102a, 102b, 102c, 102d to access PSTN 108, Internet 110, and/or other networks 112. PSTN 108 may include a circuit switched telephone network providing plain old telephone service (POTS). The Internet 110 is a common communication network such as TCP, user datagram protocol (UDP), and/or IP in the transmission control protocol/internet protocol (TCP/IP) suite. May include a global system of interconnected computer networks and devices that use protocols. Network 112 may include wired and/or wireless communications networks owned and/or operated by other service providers. For example, network 112 may include other CNs connected to one or more RANs, which may employ the same RAT or a different RAT than RAN 104.

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

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

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

Transmit/receive element 122 may be configured to transmit signals to or receive signals from a base station (e.g., base station 114a) via air interface 116. For example, in one embodiment, transmit/receive element 122 may be an antenna configured to transmit and/or receive RF signals. In embodiments, transmit/receive element 122 may be an emitter/detector configured to transmit and/or receive IR, UV, or visible light signals, for example. In another embodiment, transmit/receive element 122 may be configured to transmit and/or receive both RF and optical signals. It will be appreciated that the transmit/receive element 122 may be configured to transmit and/or receive any combination of wireless signals.

Although transmit/receive element 122 is shown in FIG. 1B as a single element, WTRU 102 may include any number of transmit/receive elements 122. More specifically, WTRU 102 may employ MIMO technology. Accordingly, in one embodiment, WTRU 102 may include two or more transmit/receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals over air interface 116. .

Transceiver 120 may be configured to modulate a signal transmitted by transmit/receive element 122 and demodulate a signal received by transmit/receive element 122. As mentioned above, WTRU 102 may have multi-mode capabilities. Accordingly, transceiver 120 may include multiple transceivers to enable WTRU 102 to communicate via multiple RATs, such as NR and IEEE 802.11, for example.

The processor 118 of the WTRU 102 may include a speaker/microphone 124, a keypad 126, and/or a display/touch pad 128 (e.g., a liquid crystal display (LCD) display unit or an organic light emitting diode (OLED) display unit. display unit) and can receive user input data therefrom. Processor 118 may also output user data to speaker/microphone 124, keypad 126, and/or display/touch pad 128. Additionally, processor 118 may access information from and store data in any type of suitable memory, such as non-removable memory 130 and/or removable memory 132. Non-removable memory 130 may include random access memory (RAM), read only memory (ROM), a hard disk, or any other type of memory storage device. Removable memory 132 may include a subscriber identity module (SIM) card, memory stick, secure digital (SD) memory card, etc. In other embodiments, processor 118 may access information from and store data within memory not physically located on WTRU 102, such as a server or home computer (not shown).

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

Processor 118 may also be coupled to a GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of WTRU 102. In addition to or instead of information from GPS chipset 136, WTRU 102 may receive location information via air interface 116 from base stations (e.g., base stations 114a, 114b) and/or 2 You can determine your location based on the timing of signals received from more than one nearby base station. It will be appreciated that the WTRU 102 may acquire location information by any suitable location determination method while still remaining consistent with an embodiment.

Processor 118 may be further coupled to other peripherals 138, which may include one or more software and/or hardware modules providing additional features, functionality, and/or wired or wireless connectivity. For example, peripherals 138 may include an accelerometer, an e-compass, a satellite transceiver, a digital camera (for photos and/or video), a universal serial bus (USB) port, and a vibration sensor. devices, television transceivers, hands-free headsets, Bluetooth® modules, frequency modulated (FM) radio units, digital music players, media players, video game player modules, Internet browsers, virtual reality and/or augmented reality (VR/AR) devices; May include activity trackers, etc. Peripheral device 138 may include one or more sensors. Sensors include gyroscopes, accelerometers, Hall effect sensors, magnetometers, orientation sensors, proximity sensors, temperature sensors, and time sensors; It may be one or more of a location information sensor, an altimeter, an optical sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, and a humidity sensor.

The WTRU 102 is capable of transmitting and receiving some or all of the signals (e.g., associated with specific subframes for both UL (e.g., for transmitting) and DL (e.g., for receiving)). May include full duplex radios that may coexist and/or be simultaneous. A full-duplex radio is capable of self-interference either through hardware (e.g., a choke) or through signal processing through a processor (e.g., a separate processor (not shown) or processor 118). It may include an interference management unit that reduces and/or substantially eliminates. In one embodiment, the WTRU 102 transmits some or all of the signals (e.g., associated with a specific subframe for the UL (e.g., for transmitting) or DL (e.g., for receiving)). And it may include a receiving half-duplex radio.

1C is a system diagram illustrating RAN 104 and CN 106 according to an embodiment. As mentioned above, RAN 104 may employ E-UTRA radio technology to communicate with WTRUs 102a, 102b, and 102c via air interface 116. RAN 104 may also communicate with CN 106.

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

Each of the eNode-Bs 160a, 160b, and 160c may be associated with a specific cell (not shown) and may be configured to process radio resource management decisions, handover decisions, scheduling of users on the UL and/or DL, etc. there is. As shown in FIG. 1C, eNode-Bs 160a, 160b, and 160c can communicate with each other through the X2 interface.

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

MME 162 may be connected to each of the eNode-Bs 162a, 162b, and 162c of 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, activating/deactivating bearers, selecting a specific serving gateway during initial attachment of the WTRUs 102a, 102b, 102c, etc. There may be responsibility. MME 162 may provide control plane functionality for switching between RAN 104 and other RANs (not shown) employing other radio technologies, such as GSM and/or WCDMA.

SGW 164 may be connected to each of the eNode Bs 160a, 160b, and 160c of the RAN 104 through the S1 interface. SGW 164 may generally route and forward user data packets to and from WTRUs 102a, 102b, and 102c. SGW 164 anchors the user plane during inter-eNode B handover, triggers paging when DL data is available for WTRUs 102a, 102b, and 102c, and maintains context for WTRUs 102a, 102b, and 102c. It can perform other functions, such as managing and storing.

SGW 164 provides access to a packet switched network, such as the Internet 110, to facilitate communication between WTRUs 102a, 102b, and 102c and IP-enabled devices. It may be connected to PGW 166 which may provide to WTRUs 102a, 102b, and 102c.

CN 106 may facilitate communication with other networks. For example, CN 106 may provide WTRUs 102a, 102b, 102c with access to a circuit-switched network, such as PSTN 108, to facilitate communication between WTRUs 102a, 102b, and 102c and traditional landline communication devices. 102c). For example, CN 106 may include an IP gateway (e.g., an IP multimedia subsystem (IMS) server) that serves as an interface between CN 106 and PSTN 108; You can communicate with this. Additionally, CN 106 may provide 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. You can.

Although the WTRU is depicted in FIGS. 1A-1D as a wireless terminal, it is contemplated that in certain representative embodiments such terminal may utilize a wired communication interface (e.g., temporarily or permanently) with a communication network.

In a representative embodiment, the other network 112 may be a WLAN.

A WLAN in infrastructure basic service set (BSS) mode may have an access point (AP) to the BSS and one or more stations (STAs) associated with the AP. The AP may have access or interface to a distribution system (DS) or other type of wired/wireless network that carries traffic in and out of the BSS. Traffic to the STA originating from outside the BSS may arrive through the AP and be delivered to the STA. Traffic originating from the STA and destined for a destination outside the BSS may be transmitted to the AP to be delivered to its respective destination. Traffic between STAs within a BSS may be transmitted through an AP, for example, where a source STA may transmit traffic to an AP and the AP may forward traffic to a destination STA. Traffic between STAs within a BSS may be considered and/or referred to as peer-to-peer traffic. Peer-to-peer traffic may be transmitted (e.g., directly) between the source STA and the destination STA using direct link setup (DLS). In certain representative embodiments, DLS may use 802.11e DLS or 802.11z tunneled DLS (TDLS). A WLAN using Independent BSS (IBSS) mode may not have an AP, and STAs within or using IBSS (e.g., all STAs) can communicate directly with each other. The IBSS mode of communication may sometimes be referred to herein as an “ad-hoc” mode of communication.

When using the 802.11ac infrastructure operating mode or a similar operating mode, the AP may transmit beacons on a fixed channel, such as the primary channel. The primary channel may be of a fixed width (e.g., a 20 MHz wide bandwidth) or may have a dynamically set width. The primary channel may be the operating channel of the BSS and may be used by the STA to establish a connection with the AP. In certain representative embodiments, Carrier Sensitive Multiple Access/Collision Avoidance (CSMA/CA) may be implemented, for example, in an 802.11 system. In the case of CSMA/CA, an STA (eg, all STAs) including an AP can detect the main channel. If the primary channel is sensed/detected and/or determined to be in use by a specific STA, the specific STA may be backed off. One STA (eg, only one station) may transmit at any given time in a given BSS.

A High Throughput (HT) STA may use a 40 MHz wide channel for communication, for example, through a combination of a basic 20 MHz channel with adjacent or non-adjacent 20 MHz channels to form a 40 MHz wide channel.

Very High Throughput (VHT) STA can support 20 MHz, 40 MHz, 80 MHz and/or 160 MHz wide channels. 40 MHz and/or 80 MHz channels can be formed by combining adjacent 20 MHz channels. A 160 MHz channel can be formed by combining eight adjacent 20 MHz channels, or by combining two non-adjacent 80 MHz channels, which can be referred to as an 80+80 configuration. For the 80+80 configuration, data can be passed through a segment parser that can split the data into two streams after channel encoding. Inverse fast Fourier transform (IFFT) processing, and time domain processing can be performed separately on each stream. Streams can be mapped to two 80 MHz channels and data can be transmitted by the transmitting STA. At the receiving STA's receiver, the operation for the 80+80 configuration described above can be reversed and the combined data can be sent with intermediate access control (MAC).

Sub-1 GHz operating modes are supported by 802.11af and 802.11ah. Channel operating bandwidths, and carriers, are reduced in 802.11af and 802.11ah compared to those used in 802.11n and 802.11ac. 802.11af supports 5 MHz, 10 MHz, and 20 MHz bandwidths in TV white space (TVWS) spectrum, while 802.11ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using non-TVWS spectrum. Support. According to an exemplary embodiment, 802.11ah may support meter-type control/machine-type communications (MTC), such as MTC devices in a macro coverage area. An MTC device may have certain capabilities, e.g., limited capabilities, including specific and/or limited bandwidth support (e.g., bandwidth only). The MTC device may include a battery with a battery life exceeding a threshold (eg, to maintain very long battery life).

A WLAN system that can support multiple channels and channel bandwidths, such as 802.11n, 802.11ac, 802.11af and 802.11ah, includes channels that can be designated as primary channels. The primary channel may have a bandwidth equal to the largest common operating bandwidth supported by all STAs in the BSS. The bandwidth of the main channel may be set and/or limited by the STA supporting the smallest bandwidth operation mode among all STAs operating in the BSS. In the example of 802.11ah, the primary channel is one that supports the 1 MHz mode (e.g., 1 It may be 1 MHz wide for STAs (e.g., MTC type devices) that only support MHz mode. Carrier detection and/or network allocation vector (NAV) settings may vary depending on the status of the primary channel. If the main channel is busy, for example, due to a STA (supporting only 1 MHz operating mode) transmitting to an AP, all available frequency bands will remain idle even though most of the available frequency bands remain idle. It can be considered in use.

In the United States, the available frequency bands that can be used by 802.11ah are 902 MHz to 928 MHz. In Korea, the available frequency bands are 917.5 MHz to 923.5 MHz. In Japan, the available frequency bands are 916.5 MHz to 927.5 MHz. The total bandwidth available for 802.11ah is 6 MHz to 26 MHz depending on the country code.

Figure 1D is a system diagram illustrating RAN 104 and CN 106 according to an embodiment. As mentioned above, RAN 104 may employ NR radio technology to communicate with WTRUs 102a, 102b, and 102c via air interface 116. RAN 104 may also communicate with CN 106.

RAN 104 may include gNBs 180a, 180b, and 180c, although it will be understood that RAN 104 may include any number of gNBs while still remaining consistent with an embodiment. gNBs 180a, 180b, and 180c may each include one or more transceivers for communicating with WTRUs 102a, 102b, and 102c via air interface 116. In one embodiment, gNBs 180a, 180b, and 180c may implement MIMO technology. For example, gNB 180a, 108b may utilize beamforming to transmit signals to and/or receive signals from gNB 180a, 180b, 180c. Accordingly, gNB 180a may use multiple antennas to transmit wireless signals to and/or receive wireless signals from WTRU 102a, for example. In an embodiment, gNBs 180a, 180b, and 180c may implement carrier aggregation technology. For example, gNB 180a may transmit multiple component carriers to WTRU 102a (not shown). 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, gNBs 180a, 180b, and 180c may implement Coordinated Multi-Point (CoMP) technology. For example, WTRU 102a may receive coordinated transmissions from gNB 180a and gNB 180b (and/or gNB 180c).

WTRUs 102a, 102b, and 102c may communicate with gNBs 180a, 180b, and 180c using transmissions associated with scalable 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. WTRUs 102a, 102b, and 102c may use subframes or transmission time intervals (TTIs) of varying or scalable length (e.g., containing varying numbers of OFDM symbols and/or varying lengths of absolute time duration). Thus, communication can be performed with gNB (180a, 180b, 180c).

gNBs 180a, 180b, and 180c may be configured to communicate with WTRUs 102a, 102b, and 102c in standalone configurations and/or non-standalone configurations. In a standalone configuration, WTRUs 102a, 102b, 102c communicate with gNBs 180a, 180b, 180c without also accessing other RANs (e.g., eNode-Bs 160a, 160b, 160c). can do. In a standalone configuration, WTRUs 102a, 102b, and 102c may utilize one or more of gNBs 180a, 180b, and 180c as mobility anchor points. In a standalone configuration, WTRUs 102a, 102b, and 102c may communicate with gNBs 180a, 180b, and 180c using signals in unlicensed bands. In a non-standalone configuration, WTRUs 102a, 102b, 102c may communicate/connect with gNBs 180a, 180b, 180c while also communicating/connecting with other RANs, such as eNode-Bs 160a, 160b, 160c. For example, WTRUs 102a, 102b, 102c may implement DC principles to communicate substantially simultaneously with one or more gNBs 180a, 180b, 180c and one or more eNode-Bs 160a, 160b, 160c. . In a non-standalone configuration, eNode-Bs 160a, 160b, 160c may serve as mobility anchors for WTRUs 102a, 102b, 102c, and gNBs 180a, 180b, 180c may serve as mobility anchors for WTRUs 102a, 102b. , may provide additional coverage and/or throughput to service 102c).

Each of the gNBs 180a, 180b, and 180c may be associated with a specific cell (not shown) and may be responsible for making radio resource management decisions, handover decisions, scheduling of users in the UL and/or DL, support for network slicing, DC, NR and Handles interactions between E-UTRA, routing of user plane data towards user plane functions (UPF) (184a, 184b), routing of control plane information towards access and mobility management functions (AMF) (182a, 182b), etc. It can be configured to do so. As shown in FIG. 1D, gNBs 180a, 180b, and 180c may communicate with each other through the Xn interface.

CN 106, shown in FIG. 1D, has at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one session management function (SMF) 183a, 183b, and possibly data It may include networks (DNs) 185a and 185b. Although the foregoing elements are shown as part of CN 106, it will be understood that any of these elements may be owned and/or operated by an entity other than a CN operator.

AMF 182a, 182b may be connected to one or more of gNBs 180a, 180b, 180c within RAN 104 via an N2 interface and may function as a control node. For example, AMF 182a, 182b may provide user authentication of WTRUs 102a, 102b, 102c, support for network slicing (e.g., handling of different protocol data unit (PDU) sessions with different requirements), and specific It may be responsible for SMF selection (183a, 183b), management of registration area, termination of non-access spectrum (NAS) signaling, mobility management, etc. Network slicing may be used by the AMF 182a, 182b to customize CN support for the WTRU 102a, 102b, 102c based on the type of service utilizing the WTRU 102a, 102b, 102c. For example, different network slices can be established for different use cases, such as services relying on ultra-reliable low-latency (URLLC) access, services relying on enhanced massive mobile broadband (eMBB) access, services for MTC access, etc. . AMF 182a, 182b between RAN 104 and other RANs (not shown) employing other radio technologies, such as LTE, LTE-A, LTE-A Pro, and/or non-3GPP access technologies, such as WiFi. Control plane functions for switching can be provided.

SMFs 183a and 183b may be connected to AMFs 182a and 182b at CN 106 via the N11 interface. SMFs 183a, 183b may also be connected to UPFs 184a, 184b at CN 106 via the N4 interface. The SMF (183a, 183b) may select and control the UPF (184a, 184b) and configure routing of traffic through the UPF (184a, 184b). SMFs 183a and 183b may perform other functions, such as UE IP address management and allocation, PDU session management, policy enforcement and QoS control, providing DL data notification, etc. PDU session types can be IP-based, non-IP-based, Ethernet-based, etc.

The UPFs 184a, 184b provide the WTRUs 102a, 102b, 102c with access to a packet-switching network, such as the Internet 110, to facilitate communication between the WTRUs 102a, 102b, and 102c. It may be connected to one or more of the gNBs 180a, 180b, and 180c of the RAN 104 via an N3 interface, which may provide 102c). UPFs 184 and 184b may perform other functions, such as packet routing and forwarding, user plane policy enforcement, multi-homed PDU session support, user plane QoS processing, DL packet buffering, mobility anchoring, etc.

CN 106 may facilitate communication with other networks. For example, CN 106 may include an IP gateway (e.g., an IP multimedia subsystem (IMS) server) that serves as an interface between CN 106 and PSTN 108; You can communicate with this. Additionally, CN 106 may provide 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. You can. In one embodiment, WTRUs 102a, 102b, 102c are connected to UPFs 184a, 184b via N3 interfaces to UPFs 184a, 184b and N6 interfaces between UPFs 184a, 184b and DNs 185a, 185b. It can be connected to the local DN (185a, 185b) through .

Considering FIGS. 1A-1D and the corresponding descriptions of FIGS. 1A-1D, WTRUs 102a-102d, base stations 114a-114b, eNode-Bs 160a-160c, MME 162 , SGW (164), PGW (166), gNB (180a to 180c), AMF (182a to 182b), UPF (184a to 184b), SMF (183a to 183b), DN (185a to 185b) and/or the present specification One or more or all of the functions described herein in conjunction with any one or more of the other device(s) described may be performed by one or more emulation devices (not shown). An emulation device may be one or more devices configured to emulate one or more or all of the functions described herein. For example, an emulation device may be used to test other devices and/or simulate network and/or WTRU functionality.

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

One or more emulation devices may perform one or more functions, including all functions, without being implemented/deployed as part of a wired and/or wireless communications network. For example, an emulation device may be utilized in a test laboratory and/or a test scenario in a non-deployed (e.g., test) wired and/or wireless communications network to implement testing of one or more components. One or more emulation devices may be test equipment. Direct RF coupling and/or wireless communication through RF circuitry (eg, which may include one or more antennas) may be used by the emulation device to transmit and/or receive data.

Reference may be made to the following abbreviations and acronyms:

3GPP 3rd Generation Partnership Project

5G 5th Generation

ARQ Automatic Repeat Request

BW Bandwidth

BWP Bandwidth Part

CB Code Block

C.B.G. Code Block Group

CBGFI CBG Flushing Out Information

CBGTI Code Block Group Transmit Indicator

CCE Control Channel Element

CORESET Control Resource Set

CRB0 Common Resource Block

CRC Cyclic Redundancy Check

DCI Downlink Control Information

DL Downlink

DMRS Demodulation Reference Signal

DMRS Demodulation Reference Symbol

FDD Frequency Division Duplex

gNB gNodeB

HARQ Hybrid Automatic Repeat Request

MAC Medium Access Control

MIB Master Information Block

NR New Radio

NSA Non-Stand Alone

OFDM Orthogonal Frequency Division Multiplexing

PBCH Physical Broadcast Channel

PDCCH Physical Downlink Control Channel

PDCCH Physical DL Control Channel

PDSCH Physical Downlink Shared Channel

PHY Physical Layer

PRACH Physical Random Access Channel

P.S.S. Primary Synchronization Sequence

PUSCH Physical Uplink Share Control Channel

RADAR Radio Detection and Ranging

RB Resource Block

R.E. Resource Element

REG Resource Element Group

RRC Radio Resource Control

RV Redundancy Version

SCS Subcarrier Spacing

SI System Information

SIB1 System Information Block 1

SPS Semi-Persistent Scheduling

SS_PBCH Synchronization and Broadcast Channel combination

SSB SS/PBCH Block

SSS Secondary Synchronization Sequence

TDD Time Division Duplex

UE User Equipment

UL Uplink

WTRU Wireless Transmit/Receive Unit

Automatic Repeat Request (ARQ) is an error control technique that relies on retransmission but discards incorrectly received data. This may lead to a decrease in ARQ efficiency. Hybrid ARQ (HARQ) utilizes these erroneous packets by storing them in a buffer memory and combining them to obtain the originally transmitted data. HARQ paired with a multiple stop-and-wait transmission protocol is a powerful error correction mechanism that does not limit throughput, as opposed to a single stop-and-wait protocol.

In recent communication systems, the need for asynchronous HARQ on both uplink and downlink has become paramount as it allows dynamic TDD as well as operation in unlicensed spectrum. Additionally, it is typical for cellular systems to support multiple HARQ processes. For example, LTE can support up to 8 multiple HARQ processes for FDD and up to 15 for TDD, while 5G can support up to 16 multiple HARQ processes.

There are two main retransmission combination techniques - chase combination and incremental redundancy. In chase combination, identical copies of the transmitted data bits are transmitted. In incremental redundancy, a combination of systematic bits and parity bits is transmitted. The first transmission may include all systematic bits. In 5G, incremental redundancy uses the default order of redundancy versions set to 0, 1, 2, 3.

A CRC is added to a large transport block and may be segmented into a number of code blocks (CBs), each block having its own CRC bit added, and then grouped into code block groups of 2, 4, 6, or 8 CBGs. do. The number of code blocks within a CBG may vary depending on the number of CBs in the initial transmission. The size of CBG is determined by the RRC message. If interference affects the CB, the entire CBG including the CB is retransmitted. The New Data Indicator (NDI) field within the DCI is used to indicate whether new data is being transmitted on the uplink or downlink. This field has a single bit and operates in toggled mode (i.e., toggling indicates new data transmission). Unlike in the downlink, there is no explicit ACK or NACK in the uplink.

Figure 2 illustrates an example downlink retransmission of CBG. As shown in Figure 2, transport block 202 includes four CBGs - CBG #1 (210), CBG #2 (212), CBG #3 (214), and CBG #4 (216). Each CBG contains two code blocks. CBG #1 (210) includes CB #1 (221) and CB #2 (222), CBG #2 (212) includes CB #3 (223) and CB #4 (224), and CBG # 3 (214) includes CB #5 (225) and CB #6 (226), and CBG #4 (216) includes CB #7 (227) and CB #8 (228). As shown in Figure 2, CB #1 (221) and CB #5 (225) experience interference. Interference may be caused by radar.

After receiving the transport block 202 from the transmitter 206, the WTRU 204 transmits a NACK 230 to the transmitter 206 because CB #1 221 and CB #5 225 are interfered with. do. Accordingly, transmitter 206 retransmits CBG #1 (210) and CBG #3 (214) to WTRU 204.

When retransmission is configured for each CBG, the receiver needs information about which CBG is being retransmitted and when to flush its buffer. This is handled through the DCI fields Code Block Group Transmit Indicator (CBGTI) and Code Block Group Flush Indicator (CBGFI). CBGTI is a bitmap indicating which CBG is being (re)transmitted in the downlink. CBGFI can be indicated by a single bit, where “1” can indicate a flush command and “0” can indicate that soft combing should be performed. In the uplink, HARQ ACK and NACK can be multiplexed with SR or CRI over PUCCH or with data over PUSCH.

HARQ timing may be indicated by a 3-bit field in DCI and may indicate the ACK timing of the uplink for PDSCH reception. HARQ timing may point to a value in the RRC configuration table. The RRC parameter K0 may indicate the slot offset at which downlink data is scheduled. This can range from 0 to 32 slots. The WTRU transmits a UL acknowledgment after the K1 slot offset. K1 ranges from 0 to 15 slots, depending on WTRU capabilities. This WTRU capability is given by N1 consisting of the PDSCH decoding delay and DMRS configuration as shown in Table 1 and Table 2 below.

[Table 1]

[Table 2]

Parameter K2 may be the slot offset required from uplink acknowledgment to downlink retransmission. The offset may also vary in the WTRU capability indicated by N2 corresponding to the PUSCH ready time. The offset can range from 0 to 32 slots. Table 3 below shows the value of N2 for PUSCH preparation time for PUSCH timing capability 1. Table 4 below shows the value of N2 for PUSCH preparation time for PUSCH timing capability 2.

[Table 3]

[Table 4]

3 illustrates example PUSCH HARQ feedback timing. As shown in FIG. 3, base station 302 transmits UL DCI for UL data scheduling to WTRU 304. The UL DCI may indicate that new UL transmission is approved after the K2 slot, where K2 is the offset between the DL slot in which the DCI is received and the UL slot in which UL data is scheduled to be transmitted on the PUSCH. Next, UL data is transmitted by WTRU 304 to base station 302 via PUSCH. If the UL data is not successfully decoded at base station 302 (i.e., CRC failure), base station 302 sends another UL for retransmission of the UL data with a new non-toggled data indicator (NDI) bit and a new K2 value. The acknowledgment may be sent to WTRU 304. The same procedure can be followed for all subsequent (re)transmissions.

4 illustrates example PDSCH HARQ feedback timing. As shown in FIG. 4, base station 402 transmits DL DCI for DL data scheduling to WTRU 404. The DL DCI may indicate that new DL transmission is approved after the K0 slot, where K0 is the offset between the DL slot in which the DCI for DL scheduling is received and the slot in which DL data is scheduled to be transmitted on the PDSCH. DCI may also indicate a K1 value, which may be an offset between the DL slot in which DL data is scheduled and the UL slot in which the corresponding ACK/NACK feedback is expected to be transmitted. Next, DL data is received by WTRU 404 via PDSCH. If the DL data is not successfully decoded at the WTRU 404 (i.e., CRC failure), the WTRU 404 may transmit a NACK after the K1 slot indicating unsuccessful decoding. The base station 404 may then transmit another DL DCI for DL data retransmission using the non-toggled NDI bit and indicate a new K0 value. The same procedure can be followed for all (re)transmissions.

HARQ multiplexing can use a multi-bit HARQ feedback message as an ACK/NACK multiple transmission block. There can be two main approaches to HARQ multiplexing: (1) semi-static codebook and (2) dynamic codebook. The base station may communicate with the WTRU which approach to use via an RRC configuration message. The semi-static codebook is a matrix that maps time instances to component carrier/CBG/MIMO layers. A semi-static approach may not be optimal for multiple carrier components because large HARQ reports will need to be transmitted.

Dynamic codebooks solve the problem of large-scale reporting as the size of the codebook changes dynamically. The core idea is to remove unscheduled carriers (i.e., ACK/NACK feedback is sent only for scheduled carriers) and use special indexing techniques to track which feedback is for which carrier. This is handled through the downlink allocation index (DAI) reported in the downlink allocation DCI. The DAI field has two indices: counter DAI (cDAI) and total DAI (tDAI), which are used for carrier aggregation. The cDAI index indicates the number of DL transmissions up to the point of DCI reception. This indexing occurs first at the carrier level and then at the temporal level. tDAI represents the total number of DL transmissions on all carriers up to the point of DCI reception.

With the capabilities of modern cellular communications systems operating at higher frequencies, interference between these systems and other military and civilian operations, such as airborne radar(s), has become a major concern. Interference from these systems (e.g. radar) could hinder the performance of 5G systems, which rely heavily on lower latency and higher throughput.

For example, in 5G, the number of CBs within a CBG may vary depending on the initial transmission. Once this number is fixed in the initial transmission, the base station will use the same number for all subsequent retransmissions. Periodic interferers, such as radar, can affect a single CB within a CBG. If decoding of the CB fails, the base station may retransmit the entire CBG, potentially wasting valuable resources. Conversely, smaller CBGs may result in frequent HARQ feedback, leading to inefficiency.

An approach to mitigate the impact of periodic interference on HARQ performance is disclosed. The base station can detect, identify and analyze the interference pattern and inform the WTRU of the corresponding HARQ approach, as described below.

In one embodiment, the transmitter may statically, semi-dynamically, or dynamically change the size of a code block group to reduce the amount of unnecessary data transmission or reduce the amount of ACK/NACK feedback. The network can choose to reduce the size of the CBG to avoid unnecessarily large retransmissions or to increase the size of the CBG to avoid frequent HARQ feedback.

Another embodiment may be based on the base station's ability to recognize interferer patterns. This embodiment may utilize CB and/or CBG interleaving techniques to transmit CBG during interference silence periods. These techniques optimally rearrange CBs and/or CBGs within a transport block to minimize the impact of interference on the transmitted CBGs.

As described above, in one embodiment, the network may change the size of the CBG based on knowledge of interference presence and interference patterns. If an interferer (e.g., radar) is present and only affects a subset of CBs within the CBG, the network can reduce the size of the CBG to include only the blocks affected by the interference.

5 is a diagram illustrating an example dynamic code block regrouping used to adjust the size of a transmitted CBG based on the presence of an interference pattern (e.g., radar). As shown in Figure 5, before resizing, transport block 502a includes two CBGs - CBG #1 (504) and CBG #2 (506). CBG #1 (504) and CBG #2 (506) each contain 4 CBs prior to CBG sizing. CBG #1 (504) includes CB #1 (521), CB #2 (522), CB #3 (523), and CB #4 (424). CBG #2 includes CB #5 (525), CB #6 (526), CB #7 (527), and CB #8 (528). Additionally, the periodic signal is interfering with CB #1 (421) and CB #5 (525). Here, before resizing, retransmission of the entire CBG is inefficient and a waste of valuable resources, so it can be prevented by reducing the size of the CBG to one CB (i.e., not grouping it).

CBG resizing can save the amount of data transmitted in the network by reducing the amount of unnecessary CB retransmissions, thereby improving delay and throughput. As shown in Figure 5, one way to design the transport block 502b may be to resize each CBG to contain only one CB. After dynamic CBG sizing, transport block 502b is configured with eight CBGs - CBG #1 (511), CBG #2 (512), CBG #3 (513), CBG #4 (514), CBG #5 (515), Includes CBG #6 (516), CBG #7 (517), and CBG #8 (518). Each CBG contains one CB. After dynamic CBG sizing, only CBG #1 (511) and CBG #5 (515) need to be retransmitted because each CBG contains only one CB. Conversely, if there is no interferer, the network may choose to transmit a larger CBG to save uplink signaling.

Periodic signals may interfere with the same CB instance in each CBG. For example, in Figure 5, the periodic signal is transmitted from each of the two CBGs (i.e., CBG #1 (504) and CBG #2 (506)) to the first CB (i.e., CB #1 (521) and CB #5 (525). )))).

Figure 6 illustrates another example of dynamic code block regrouping used to adjust the size of a transmitted CBG based on the presence of interference. As shown in Figure 6, if an interference pattern affects a set of contiguous CBs that are larger than the size of the CBG, the network can increase the size of the CBG so that all affected CBs are contained within one CBG. 6, prior to dynamic CBG sizing, transport block 602a has eight total CBGs - CBG #1 (611), CBG #2 (612), CBG #3 (613), CBG #4 (614), CBG #5 (615), CBG #6 (616), CBG #7 (617), and CBG #8 (618). Before dynamic CBG sizing, each CBG contains only one CB. CBG #1 (611) includes CB #1 (621), CBG #2 (612) includes CB #2 (622), CBG #3 (613) includes CB #3 (623), and , CBG #4 (614) includes CB #4 (624), CBG #5 (615) includes CB #5 (625), and CBG #6 (616) includes CB #6 (626). And, CBG #7 (617) includes CB #7 (627), and CBG #8 (618) includes CB #8 (628). Here, four CBs (CB #1 (621), CB #2 (622), CBD #5 (615), and CBD #6 (616)) are affected by interference (e.g., radar).

After dynamic CBG resizing, transport block 602b contains four CBGs - CBG #1 (631), CBG #2 (632), CBG #3 (633), and CBG #4 (634). After resizing, the four affected CBs are grouped together into two individual CBGs. As shown in Figure 6, CBG #1 includes CB #1 (611) and CB #2 (612), and CBG #3 (633) includes CB #5 (615) and CB #6 (626). Includes. Grouping CBs into CBGs of size 2 improves uplink metrics by saving uplink ACK/NACK.

Due to CBG sizing, the last CBG may have fewer CBs compared to previous CBGs of the same TB. However, as shown in Figure 7, this problem can be solved by inserting a filler CB at the beginning or end of the transport block. 7 is a diagram illustrating example code block division, filler insertion, CRC insertion, and CB grouping.

As shown in Figure 7, the network segments the CB of transport block 702 at 704. Next, at 706, the network inserts a biller bit into the last CB 720. At 708, a CRC bit is added to each CB, including CB 720. At 710, CBs are grouped.

Figure 8 illustrates an example process 800 for CBG sizing. At 802, the base station may detect an interference pattern. Interference patterns can be caused by radar. At 804, the base station may determine that the interference pattern affects one or more CBs within one or more CBGs. For example, as shown in Figure 5, in a situation where there are two CBGs (each with four CBs), each of the two CBGs may have one CB affected by interference. In another example, as shown in Figure 6, there may be eight CBGs (each with one CB), where four CBs are affected by interference. At 806, the base station may adjust the size of one or more CBGs. In one embodiment, the adjustment may include reducing the size of each CBG (as shown in Figure 5). In another embodiment, the adjustment may include increasing the size of each CGB (as shown in Figure 6). At 808, the base station may transmit information associated with coordination of one or more CBGs to the WTRU.

As described below, the network can indicate changes in CBG sizing to the WTRU statically, semi-dynamically or dynamically.

In one embodiment, the network may communicate to the emerging UE whether to use static CBG sizing via a MIB message.

In the static approach, the network can utilize spare bits in the MIB message to indicate to the emerging UE whether to use CBG sizing. This spare bit may be referred to as “staticCbgSizing”. A bit value set to “0” may indicate legacy CBG behavior (i.e., the number of CBs depends on the initial transmission). A bit value set to “1” may indicate one CB per CBG HARQ configuration.

When staticCbgSizing is enabled, connected WTRUs may continue to use the legacy CBG sizing unless a new MIB is received. On the other hand, emerging WTRUs may assume that interferers are present and that all transmitted CBGs consist of only one CB. An emerging WTRU may continue to use this assumption as long as it is connected to the network and until a new MIB is received with staticCbgSizing set to "0".

The network can utilize spare bits in the MIB to indicate whether to use static CBG sizing. For example, as described above, a bit value of “0” may indicate legacy CBG behavior, while a bit value of “1” may indicate one code block per group of code blocks. This approach can be utilized when there is a short pulse interfering signal that can affect a single CB (e.g. a radar signal). The MIB message below may be used to communicate to emerging WTRUs whether the network uses static CBG sizing.

When staticCbgSizing is enabled (i.e. set to "1"), attached WTRUs can continue to use legacy CBG sizing. However, emerging WTRUs may assume that narrowband interferers are present and that all transmitted CBGs consist of only one CB. An emerging WTRU may continue to use this assumption as long as it is connected to the network and until it reads a new MIB with staticCbgSizing set to "0".

Additionally, the WTRU may inform the network of the possibility of supporting static CBG sizing. The network can selectively enable or disable these features for the WTRU based on the WTRU capabilities and the requirements of the network. The WTRU may advertise its capabilities to the network through information messages as shown in Table 5 below.

[Table 5]

If a WTRU indicates that it does not support static CBG sizing, the network may use legacy behavior for all CBGs transmitted to that WTRU.

In another embodiment, the network may configure the WTRU to periodically apply a different CBG size for a certain duration based on current interference characteristics. In this embodiment, CBG sizing is configured semi-dynamically in the WTRU via an RRC reconfiguration message.

The new information elements are the number of CBs per CBG, the duration of the CBG sizing ON/OFF cycle, the duration of the ON period in the slot, the duration of the slot after the RRC reconfiguration message to start the CBG sizing cycle, and the duration of the slot after the RRC reconfiguration message to start the CBG sizing cycle. It is proposed to represent the number of consecutive slots that can follow a cycle. After expiration of the CBG sizing duration, the WTRU reverts to legacy behavior, which assumes that the retransmission has the same CBG size as the initial transmission.

The RRC reconfiguration message, which may include parameters to support semi-dynamic CBG sizing, is shown in bold below.

Figure 9 illustrates an example of RRC configuration CBG sizing. In Figure 9, the following parameters are defined: CbgSizingStartOffset, CbgSizingTimer, CbgSizingOnDurationTimer, and CbgSizingCycle.

CbgSizingCycle may define the duration of one “CBG Sizing ON Time” and one “CBG Sizing OFF Time” in a slot. CbgSizingOnDurationTimer can define the duration of the "CBG Sizing ON Time" in a slot within one CBGSizingCycle. CbgSizingStartOffset can define the duration in the slot after the RRC reconfiguration message to start the CbgSizingCycle. CbgSizingTimer can define the number of consecutive slots in which the WTRU must follow the CBG sizing cycle after CbgSizingStartOffset.

As shown in Figure 9, semi-dynamic CBG sizing 902 may begin after two slots and continue for the next 24 slots. A CBG sizing 902 cycle may be 6 slots in length with an “on duration” of 2 slots. During periods when CBGSizingOnDuration is on, the WTRU may use "nrofCbsPerCbg" as the default CBG size. After expiration of CbgSizingTimer, the WTRU may revert to legacy behavior, which assumes the retransmission has the same CBG size as the initial transmission.

The WTRU may need to inform the network whether it supports semi-dynamic CBG sizing. The network can selectively enable or disable these features for the WTRU based on the WTRU capabilities and the requirements of the network. A WTRU may advertise its capabilities to the network through information messages as shown in Table 6 below.

[Table 6]

In one embodiment, fully dynamic CBG sizing may occur via DCI. The new DCI parameter “CB transmission information” may indicate the number of CBs in the CBG. The network can dynamically change the CBG size through DCI to adapt to the different characteristics of radar interference.

The CBG can dynamically resize the radar signal to fit within a single CBG of minimal size, reducing the number of CB retransmissions. Each (re)transmission will follow the CBG sizing indicated by the corresponding DCI message. If this parameter is not configured, the WTRU may follow legacy HARQ behavior (i.e., retransmissions have the same CBG size as the initial transmission).

As indicated below, the RRC reconfiguration message may indicate the maximum code block group per transport block.

As shown in Table 7 below, CBG transmission information may be displayed in DCI format 0_1 and format 1_1. A new parameter “CB transmission information” can be added to indicate the number of CBs in the CBG. The network can dynamically change the CBG size through DCI to adapt to the characteristics of interference, such as radar interference. Unlike the standard implementation, where the CBG of a retransmission contains the same number of CBs as the TB's original transmission, the CBG can be resized so that interfering signals (e.g. radar signals) fit within a single CBG of minimal size, thus reducing the number of CB retransmissions. It can be reduced.

[Table 7]

To support dynamic CBG sizing, a WTRU may report dynamic CBG sizing support as part of FeatureSetDownlink in the WTRU Capability Information message. In Table 8 below, "Yes" in the columns of "FDD-TDD DIFF" and "FR1-FR2 DIFF" may indicate that the WTRU capability field may have a different value between FDD and TDD or between FR1 and FR2, and " “No” may indicate otherwise. A “Yes” in the “M” column may indicate that the associated feature is required, and a “No” may indicate that the associated feature is optional. The “Per” column may indicate the level at which the associated parameter is included. For example, “WTRU” in the “per” column may indicate that the associated parameter is signaled per WTRU.

If the WTRU is unable to support this feature (i.e., read the CB Transmit Information field in the DCI), the base station may continue to transmit the legacy DCI format to the WTRU. If the WTRU can support these features, it will indicate them as part of the WTRU capability report and begin reading the new DCI format.

[Table 8]

If a WTRU in the network can support dynamic CBG sizing, the WTRU can assume dynamic CBG sizing as the default configuration without the need to use spare bits in the MIB. In this case, the WTRU can directly use the dynamic information provided by the new DCI to determine the number of CBGs per retransmission and the size of the CBG.

As described above, if the WTRU is configured to receive CBG-based transmission, that is, it has received the upper layer parameter CodeBlockGroupTransmission for PDSCH.

For initial transmission of a TB, as indicated by the new data indicator field in the scheduling DCI, the WTRU may assume that all code block groups are present. In the case of a retransmission of a TB, as indicated by the New Data Indicator field in the scheduling DCI, the WTRU may assume that the CBGTI field in the scheduling DCI indicates whether the TB's CBG is present in the transmission.

In the CBGTI field, a bit value of “0” may indicate that the corresponding CBG is not transmitted, and “1” may indicate that it is transmitted. If the CBG Flushing Out Information (CBGFI) field of the scheduling DCI is present, CBGFI may be set to "0", indicating that a previously received instance of the same CBG being transmitted may be corrupted. A CBGFI set to “1” may indicate that the retransmitted CBG is combinable with a previously received instance of the same CBG.

The CBG does not necessarily need to contain the same number of CBs as the initial transmission of the transport block. The WTRU may read the field “CB Transmit Information” of the scheduling DCI to determine the size of the transmitted CBG. After determining which CBG is transmitted through the CBG transmission information, the WTRU reads the CB transmission information to determine the size of the CBG.

Figure 12 is a diagram illustrating an example process 1200 of CBG sizing based on WTRU feedback. At 1210, the WTRU may receive a first DCI indicating the first CBG size from the base station. At 1220, the WTRU may receive a TB containing one or more CBGs. One or more CBGs may include one or more CBs. At 1230, the WTRU may perform a cyclic redundancy check (CRC) on the received TB, including one or more CBs. At 1240, the WTRU may receive a second DCI indicating the second CBG size from the base station. The second CBG size may be based on transmitted feedback. The WTRU may then receive transmissions according to the second CBG size from the base station.

The transmitted feedback may be an acknowledgment (ACK) or a negative acknowledgment (NACK). When the WTRU transmits an ACK, the second CBG size may be larger than the first CBG size. If the WTRU transmits a NACK, the second CBG size may be smaller than the first CBG size.

In another embodiment, CB and CBG interleaving may be used to mitigate the effects of burst errors caused by interference (e.g., radar interference). Interleaving allows CB and CBG to be arranged within the same transport block before being transmitted over the wireless channel. The arrangement takes place in such a way that some CBG can be transmitted during the interferer's "quiet periods".

Figure 10 illustrates the impact of interference without example CB/CBG interleaving. Transport block 902 includes four CBGs - CBG #1 (1004), CBG #2 (1006), CBG #3 (1008), and CBG #4 (1010). CBG #1 (1004) includes CB #1 (1011) and CB #2 (1012). CBG #2 (1006) includes CB #3 (1013) and CB #4 (1014). CBG #3 (1008) includes CB #5 (1015) and CB #6 (1016). CBG #4 (1010) includes CB #7 (1017) and CB #8 (1018). The interfering signal interferes with CB #2 (1012), CB #3 (1013), CB #6 (1016), and CB #7 (1017). As shown in Figure 10, without interleaving, at least one CB within each CBG would be received incorrectly and it would be necessary to retransmit all CBGs.

Figure 11 illustrates example CB/CBG interleaving. Similar to transport block 1002 of FIG. 10, transport block 1102 includes CBG #1 (1104), CBG #2 (1106), CBG #3 (1108), and CBG #4 (1110). CBG #1 (1104) includes CB #1 (1111) and CB #2 (1112). CBG #2 (1106) includes CB #3 (1113) and CB #4 (1114). CBG #3 (1108) includes CB #5 (1115) and CB #6 (1116). CBG #4 (1110) includes CB #7 (1117) and CB #8 (1118).

After CB interleaving, CBG #1 (1104) contains CB #1 (1111) and CB #3 (1113), and CBG #2 (1106) contains CB #4 (1114) and CB #2 (1112). And CBG #3 (1108) includes CB #5 (1115) and CB #7 (1117), and CBG #4 (1110) includes CB #8 (1118) and CB #6 (1116). As shown in Figure 10, the transmitter manages to transmit CBG #1 (1104) and CBG #3 (1108) within the interferer's silent period. As a result, CBG #1 (1104) and CBG #3 (1108) will be received without error and will not need to be retransmitted.

The network may signal the use of CB/CBG interleaving to the WTRU via MIB messages. The network may use spare bits in the MIB to indicate activation/deactivation of these features (e.g., “0” to disable CB/CBG interleaving and “1” to enable CB/CBG interleaving). As shown below, the network can use simple forms of interleaving, such as an odd-even pattern. In an odd-even interleaver, the first CBG may include the first N odd CBs, the second CBG may include the first N even CBs, the third CBG may include the second N odd CBs, and The fourth CBG includes the second N even CBs, and so on.

The WTRU implementation can support CB/CBG interleaving by reading the MIB parameter cb-CbgInterleaving. The impact of these solutions is more pronounced in emerging UEs after CB/CBG interleaving is enabled. However, connected UEs may experience excessive BLER, which may require them to disconnect and reconnect to the network, thus acquiring a new MIB with the cb-CbgInterlaving bit set to "1". The odd-even deinterleaver in the WTRU may regroup the CBs such that the first CBG contains the first N CBs of the first N CBGs and the second CBG contains the second N CBs of the first N CBGs. Includes, the third CBG includes the 2nd N CBs of the 2nd N CBGs, the fourth CBG includes the 2nd N CBs of the 2nd N CBGs, etc.

Dynamic CBG sizing allows the transmitter to dynamically change the size of the CBG based on knowledge of the interference pattern. This operation may involve: (1) the gNB may analyze the interference pattern, or an external node may transmit information characterizing the interferer's operation to the gNB; (2) the gNB can utilize this information to determine which code blocks may be affected by interference; (3) The gNB may make a dynamic decision on whether to increase or decrease the size of the CBG to optimize HARQ feedback and the amount of retransmitted data.

CB and CBG interleaving can scramble the positions of CB and CBG based on interference pattern knowledge. Scrambling operations may involve the following: (1) the gNB may analyze the interference pattern, or an external node may transmit information characterizing the interferer's operation to the gNB; (2) the gNB can utilize this information to determine the interferer's silence period; (3) The gNB may make a dynamic decision on how to interleave CBs and CBGs such that the CBs of a particular CBG fall within such silence period.

The detected interference pattern (eg, radar interference pattern) may be measured by a base station and/or external sensor. Additionally, the detected interference pattern may be based on feedback from one or more WTRUs.

Although features and elements are described above in specific combinations, those skilled in the art will recognize that each feature or element may be used alone or in any combination with other features and elements. Additionally, the methods described herein may be implemented as a computer program, software, or firmware incorporated into a computer-readable medium for execution by a computer or processor. Examples of computer-readable media include electronic signals (transmitted over a wired or wireless connection) and computer-readable storage media. Examples of computer-readable storage media include read-only memory (ROM), random access memory (RAM), registers, cache memory, semiconductor memory devices, magnetic media such as internal hard disks and removable disks, magneto-optical media, and CD-ROMs. Includes, but is not limited to, optical media such as discs and digital versatile discs (DVDs). The processor and associated software may be used to implement a radio frequency transceiver for use in a WTRU, UE, terminal, base station, RNC, or any host computer.

Claims (23)

1. A method performed by a wireless transmit/receive unit (WTRU), comprising:
Receiving, from a base station, first downlink control information (DCI) indicating a first code block group (CBG) size;
Receiving, from the base station, a transport block (TB) comprising one or more CBGs, the one or more CBGs comprising one or more code blocks (CBs);
performing a cyclic redundancy check (CRC) on the received TB;
transmitting feedback based on the CRC to the base station; and
Receiving, from the base station, a second DCI indicating a second CBG size, wherein the second CBG size is based on the transmitted feedback. The method of claim 1, wherein if the feedback is an acknowledgment (ACK), the second CBG size is greater than the first CBG size. The method of claim 1, wherein if the feedback is a negative acknowledgment (NACK), the second CBG size is smaller than the first CBG size. As a method performed by a base station,
detecting an interference pattern;
determining whether the interference pattern affects one or more code blocks (CBs) within one or more code block groups (CBGs);
adjusting the size of the one or more CBGs; and
Transmitting information associated with the adjustment of the size of the one or more CBGs to a wireless transmit/receive unit (WTRU). 5. The method of claim 4, wherein the interference pattern is caused by a radar (radio detection and ranging) system. 5. The method of claim 4, wherein adjusting the size of the one or more CBGs includes increasing the number of CBs within the one or more CBGs. 5. The method of claim 4, wherein adjusting the size of the one or more CBGs comprises reducing the number of CBs within the one or more CBGs. 5. The method of claim 4, wherein the interference pattern affects the same CB instance in each CBG. 5. The method of claim 4, wherein the base station detects the interference pattern based on feedback from one or more WTRUs. 5. The method of claim 4, wherein transmitting the information regarding the adjustment of the size of the one or more CBGs is performed via master information block (MIB) signaling. 5. The method of claim 4, wherein transmitting the information regarding the adjustment of the size of the one or more CBGs is performed via radio resource control (RRC) signaling. 12. The method of claim 11, wherein the RRC signaling includes information indicating CBG sizing duration. 5. The method of claim 4, wherein transmitting the information regarding the adjustment of the size of the one or more CBGs is performed via downlink control information (DCI) signaling. As a base station,
transmitter;
receiving set; and
Contains a processor,
the receiver and processor are configured to detect an interference pattern;
The processor,
determine whether the interference pattern affects one or more code blocks (CBs) within one or more code block groups (CBGs);
configured to adjust the size of the one or more CBGs;
and the transmitter is configured to transmit information associated with the adjustment of the size of the one or more CBGs to a wireless transmit/receive unit (WTRU). 15. The base station of claim 14, wherein the interference pattern is caused by a radar (radio detection and ranging) system. 15. The base station of claim 14, wherein adjusting the size of the one or more CBGs includes increasing the number of CBs within the one or more CBGs. 15. The base station of claim 14, wherein adjusting the size of the one or more CBGs includes reducing the number of CBs within the one or more CBGs. 15. The base station of claim 14, wherein the interference pattern affects the same CB instance in each CBG. 15. The base station of claim 14, wherein the processor detects the interference pattern based on feedback from one or more WTRUs. 15. The base station of claim 14, wherein transmitting the information regarding the adjustment of the size of the one or more CBGs is performed via master information block (MIB) signaling. 15. The base station of claim 14, wherein transmitting the information regarding the adjustment of the size of the one or more CBGs is performed via radio resource control (RRC) signaling. 22. The base station of claim 21, wherein the RRC signaling includes information indicating a CBG sizing duration. 15. The base station of claim 14, wherein transmitting the information regarding the adjustment of the size of the one or more CBGs is performed via downlink control information (DCI) signaling.

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