Cyclic partitioning method and procedure for phase noise compensation in CP-OFDM

Abstract

Disclosed herein are embodiments of handling wireless communications, where one or more of these embodiments deal with phase noise (PN) compensation techniques in which multiple sets of reference symbols are transmitted by partitioning allocated physical resource blocks (PRBs) computations into appropriate sizes (e.g., for example, for example, for example, for example, for example, for example, for example, for example, for example, for example, for example, for example, for example, for example, for example, for example, for example, or for example, for example, for example, for example, for example, for example, for example. ), and ensures frequency domain cyclic symmetric transmission from the sender entity side that adds cyclic subcarriers to each group. There may be one or more technical designs to select a suitable number and size of groups to enable a suitable level of PN compensation at a receiving entity and provide various methods to ensure cyclic symmetry within each group. One or more methods may be capable of adapting the instantaneous channel condition and the PN characteristics of the transceiver per user.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 346,180 filed on May 26, 2022 and U.S. Provisional Application No. 63 / 394,452 filed on August 2, 2022, the contents of which are incorporated herein by reference. Background Art

[0003] In wireless systems, wireless devices (receivers or transmitters) must deal with problems that may occur in the signal. There is a need to ensure that as wireless technology advances, one or more novel methods are available to address these problems. Summary of the invention

[0004] Disclosed herein are multiple embodiments for processing wireless communications, wherein one or more of these embodiments specifically deal with phase noise (PN) compensation techniques in which multiple groups of reference symbols are sent by the following actions: computationally partitioning the allocated physical resource blocks (PRBs) into groups of appropriate size (e.g., equal to or less than the coherence bandwidth of the channel), and ensuring frequency domain cyclic symmetric transmission from the transmitting entity side that adds cyclic subcarriers to each group. There may be one or more designs to select the appropriate number and size of groups to enable a suitable level of PN compensation to be achieved at the receiving entity, and to provide various methods to ensure cyclic symmetry within each group. One or more methods may be able to adapt the instantaneous channel conditions and the PN characteristics of the transceiver per user (e.g., device). BRIEF DESCRIPTION OF THE DRAWINGS

[0005] A more detailed understanding may be obtained from the following description given by way of example in conjunction with the accompanying drawings, in which like reference numerals indicate like elements, and in which:

[0006] Figure 1A is a system diagram illustrating an example communication system in which one or more disclosed embodiments may be implemented;

[0007] Figure 1B is an example of an embodiment in which Figure 1A A system diagram of an example wireless transmit / receive unit (WTRU) for use within the illustrated communication system;

[0008] Figure 1C is an example of an embodiment in which Figure 1A a system diagram of an example Radio Access Network (RAN) and an example Core Network (CN) used within the illustrated communication system;

[0009] Figure 1D is an example of an embodiment in which Figure 1Aa system diagram of another example RAN and another example CN used within the illustrated communication system; and

[0010] Figure 2 An example of PT-RS signal allocation in CP-OFDM 5G NR for DM-RS configuration types 1 and 2 is illustrated;

[0011] Figure 3 An example of cyclically dividing M subcarriers into L subcarrier groups is illustrated, wherein a frequency domain cyclic prefix / cyclic suffix structure is prepended and postpended to each subcarrier group in the subcarrier groups respectively;

[0012] Figure 4 An example of FD-CP / CS insertion in a subcarrier group is illustrated;

[0013] Figure 5 An example of a phase noise response is illustrated, which shows a single-sided spectral width of -120dBc / Hz power spectral density;

[0014] Figure 6 An example illustrating details of a single FD-CP insertion per subcarrier group;

[0015] Figure 7 An example illustrating the details of a single FD-CS insertion per subcarrier group;

[0016] Figure 8 An example illustrating details of combined FD-CP / CS insertion for each subcarrier group is shown;

[0017] Fig. 9 An example of transmit processing steps for generating a CP-OFDM signal based on phase noise cyclic partitioning is illustrated;

[0018] Fig.10 An example of the receiving processing steps in the proposed loop partitioning method is illustrated;

[0019] Fig.11 An example of a procedure for transmitting CP-OFDM symbols based on phase noise cycle partitioning is illustrated;

[0020] Fig.12 An example procedure for transmitting CP-OFDM symbols based on phase noise cycle partitioning is illustrated;

[0021] Fig.13 An example procedure for receiving CP-OFDM symbols based on phase noise cycle partitioning is illustrated; and

[0022] Fig.14 Example methods for determining and indicating high phase noise in accordance with one or more techniques described herein are illustrated. DETAILED DESCRIPTION

[0023] Disclosed herein are multiple embodiments, examples, techniques, and methods for handling wireless communications, wherein one or more of these methods specifically handle phase noise (PN) compensation techniques in which multiple groups of reference symbols are sent by computationally partitioning the allocated physical resource blocks (PRBs) into groups of appropriate size (e.g., equal to or less than the coherence bandwidth of the channel), and ensuring frequency domain cyclic symmetric transmission from the transmitting entity side that adds cyclic subcarriers to each group. There may be one or more techniques to select the appropriate number and size of groups to enable a suitable level of PN compensation to be achieved at the receiving entity and to ensure cyclic symmetry within each group. One or more methods may be able to adapt the instantaneous channel conditions and the PN characteristics of the transceiver on a per-user (e.g., per-device) basis.

[0024] Additionally, various methods for wireless communication are disclosed herein, wherein one or more of these methods may be specifically used for phase noise compensation in transmission based on cyclic division of subcarriers, capable of adapting instantaneous channel conditions and / or phase noise characteristics of the transceiver on a per-user (e.g., per-device) basis. One or more of these methods may include obtaining phase noise information characterizing the amount of phase noise experienced in the communication link. One or more of these methods may include determining the coherence bandwidth B of the channel. coh One or more of these methods may include based on B coh and phase noise information to select the subcarrier group size M, the length of the frequency domain cyclic prefix L CP and the length L of the frequency domain cyclic suffix CS One or more of these methods may include determining whether a high phase noise indication is reported by the receiving entity and / or whether the coherence bandwidth of the channel is lower than the allocated bandwidth of the user so as to adjust the subcarrier cyclic partitioning parameters M, L CP and L CS One or more of these methods may include updating L based on a high phase noise indication received from a receiving entity. CP and L CS One or more of these methods may include performing a rate matching function to adjust the amount of data to be mapped to the available physical resources after taking into account the frequency domain cyclic prefix and / or cyclic suffix fields. One or more of these methods may include transmitting a packet containing, for example, M, L CP and L CS One or more of these methods may include sending CP-OFDM symbols.

[0025] Additionally, various methods for wireless communications are disclosed herein, wherein one or more of these methods may be specifically used for phase noise compensation in reception based on cyclic division of subcarriers, capable of adapting instantaneous channel conditions and / or phase noise characteristics of the transceiver on a per-user basis. One or more of these methods may include receiving CP-OFDM symbols. One or more of these methods may include performing channel estimation, equalization, and / or common phase error compensation in the frequency domain of the received CP-OFDM. One or more of these methods may include, for example, obtaining a subcarrier group size M and a length L of a frequency domain cyclic prefix via signaling indications. CP and / or the length L of the frequency domain cyclic suffix CS One or more of these methods may include methods based on M, L CP and / or L CS The present invention relates to a method for averaging an estimated phase noise inter-carrier interference (ICI) component in each subcarrier group by averaging a residual phase noise ICI power greater than zero, and performing phase noise ICI compensation. One or more of these methods may include demodulating the subcarriers and comparing the residual phase noise ICI power to a threshold. One or more of these methods may include determining a phase noise characteristic, such as a phase noise spectrum width, based on the residual phase noise ICI power being greater than a threshold. One or more of these methods may include transmitting a high phase noise indication, which includes information about the amount of phase noise expected or experienced in the communication link, such as phase noise capability information and / or phase noise spectrum width.

[0026] 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 through sharing of 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 discrete Fourier transform spread OFDM (ZT-UW-DFT-S-OFDM), unique word OFDM (UW-OFDM), resource block filtered OFDM, filter bank multi-carrier (FBMC), etc.

[0027] like Figure 1AAs shown, the communication system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, a radio access network (RAN) 104, a core network (CN) 106, a public switched telephone network (PSTN) 108, the 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 elements. Each of the WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and / or communicate in a wireless environment. For example, the WTRUs 102a, 102b, 102c, 102d (any of which may be referred to as a station (STA)) may be configured to send 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 Mi-Fi 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), consumer electronic devices, devices 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. Any reference to a "user" herein may be interchangeable with a user's device and / or a WTRU. For example, where a user is assigned bandwidth, this is equivalent to the case where the WTRU is assigned bandwidth by receiving a configuration grant for a specific bandwidth to use.

[0028] 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 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, 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 evolved Node B (eNB), a Home Node B, a Home evolved Node B, a next generation Node B (such as a gNode B (gNB)), a new radio (NR) Node B, a site controller, an access point (AP), a wireless router, and the like. While the base stations 114a, 114b are each depicted as a single element, it will be appreciated that the base stations 114a, 114b may include any number of interconnected base stations and / or network elements.

[0029] The base station 114a may be part of the RAN 104, which may also include other base stations and / or network elements (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 a cell (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 one embodiment, the base station 114a may employ multiple-input multiple-output (MIMO) technology and may utilize multiple transceivers for each sector of the cell. For example, beamforming may be used to send and / or receive signals in a desired spatial direction.

[0030] The base stations 114a, 114b may communicate with one or more of the WTRUs 102a, 102b, 102c, 102d over 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).

[0031] More specifically, as noted 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 and the WTRUs 102a, 102b, 102c may implement a radio technology, such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), that may use Wideband CDMA (WCDMA) to establish the air interface 116. 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).

[0032] In one 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-APro).

[0033] 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 NR.

[0034] 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 utilized by the WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and / or transmissions transmitted to / from multiple types of base stations (e.g., eNBs and gNBs).

[0035] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement radio technologies such as 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.

[0036] Figure 1AThe base station 114b in the 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 home, 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 a radio technology 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 a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In yet another embodiment, the base station 114b and the WTRUs 102c, 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR, etc.) to establish a picocell or a femtocell. As Figure 1A As shown, the base station 114 b may have a direct connection to the Internet 110. Therefore, the base station 114 b may not need to access the Internet 110 via the CN 106.

[0037] The RAN 104 may be in communication with the CN 106, which may be any type of network configured to provide 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, delay requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, etc. The CN 106 may provide call control, billing services, mobile location-based services, pre-paid calling, Internet connectivity, video distribution, etc., and / or perform high-level security functions, such as user authentication. Although not described in detail in the specification, the CN 106 may be configured to provide voice, data, applications, and / or Voice over Internet Protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. Figure 1A Although not shown in the figure, it will be appreciated that the RAN 104 and / or the CN 106 may be in direct or indirect communication with other RANs that employ the same RAT as the RAN 104 or a different RAT. For example, in addition to being connected to the RAN 104, which may utilize NR radio technology, the CN 106 may also be in communication with another RAN (not shown) that employs GSM, UMTS, CDMA 2000, WiMAX, E-UTRA, or WiFi radio technology.

[0038] The CN 106 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 communication networks 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 employ the same RAT as the RAN 104 or a different RAT.

[0039] 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.

[0040] 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 keypad 126, a display / touchpad 128, non-removable memory 130, 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.

[0041] 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 associated with a DSP core, a controller, a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), any other type of integrated circuit (IC), a state machine, etc. The processor 118 may perform signal decoding, 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 is understood that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0042] The send / receive element 122 may be configured to send a signal to a base station (e.g., base station 114a) or receive a signal from the base station by air interface 116. For example, in one embodiment, the send / receive element 122 may be an antenna configured to send and / or receive an RF signal. In one embodiment, the send / receive element 122 may be a transmitter / detector configured to send and / or receive, for example, IR, UV or visible light signals. In another embodiment, the send / receive element 122 may be configured to send and / or receive both RF signals and optical signals. It should be understood that the send / receive element 122 may be configured to send and / or receive any combination of wireless signals.

[0043] Although the transmit / receive element 122 Figure 1B 1 as a single element, the WTRU 102 may include any number of transmit / receive elements 122. More specifically, the WTRU 102 may employ MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit / receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals over the air interface 116.

[0044] 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 noted above, the WTRU 102 may have multi-mode capabilities. For example, the transceiver 120 may include multiple transceivers for enabling the WTRU 102 to communicate via multiple RATs, such as NR and IEEE 802.11.

[0045] The processor 118 of the WTRU 102 may be coupled to and may receive user input data from a speaker / microphone 124, a keypad 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 keypad 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).

[0046] 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.

[0047] 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 nearby 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.

[0048] The processor 118 may also be coupled to other peripherals 138, which may include one or more software modules 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. The sensor may be one or more of the following: a gyroscope, an accelerometer, a Hall effect sensor, a magnetometer, an orientation sensor, a proximity sensor, a temperature sensor, a time sensor; a geographic location sensor, an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, a humidity sensor, etc.

[0049] The WTRU 102 may include a full-duplex radio for which transmission and reception of some or all of the signals (e.g., associated with specific subframes for both UL (e.g., for transmission) and DL (e.g., for reception)) may be concurrent and / or simultaneous. The full-duplex radio may include an interference management unit for reducing and / or substantially eliminating self-interference via signal processing performed by hardware (e.g., a choke) or via a processor (e.g., a separate processor (not shown) or via the processor 118). In an embodiment, the WTRU 102 may include a half-duplex radio for which transmission and reception of some or all of the signals (e.g., associated with specific subframes for both UL (e.g., for transmission) or DL ​​(e.g., for reception)) may be concurrent and / or simultaneous.

[0050] Figure 1C 1 is a system diagram illustrating the RAN 104 and the CN 106 in accordance with an embodiment. As noted above, the RAN 104 may employ an E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0051] The RAN 104 may include evolved Node-Bs 160a, 160b, 160c, though it will be appreciated that the RAN 104 may include any number of evolved Node-Bs while remaining consistent with an embodiment. The evolved Node-Bs 160a, 160b, 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the evolved Node-Bs 160a, 160b, 160c may implement MIMO technology. Thus, the evolved Node-B 160a, for example, may use multiple antennas to transmit wireless signals to and / or receive wireless signals from the WTRU 102a.

[0052] Each of the evolved Node Bs 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, the eNode-Bs 160a, 160b, 160c may communicate with one another via an X2 interface.

[0053] Figure 1C The illustrated CN 106 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 depicted as part of the CN 106, it should be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0054] The MME 162 may be connected to each of the evolved Node-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 radio technologies, such as GSM and / or WCDMA.

[0055] The SGW 164 may be connected to each of the evolved Node-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 an inter-evolved Node-B handover, triggering paging when DL data is available for the WTRUs 102a, 102b, 102c, managing and storing the context of the WTRUs 102a, 102b, 102c, and the like.

[0056] 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.

[0057] 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 acts 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 networks and / or wireless networks owned and / or operated by other service providers.

[0058] Although the WTRU Figures 1A to 1D Although described as wireless terminals, it is contemplated that in certain representative embodiments, such terminals may (eg, temporarily or permanently) use a wired communications interface with a communications network.

[0059] In a representative embodiment, the other network 112 may be a WLAN.

[0060] A WLAN in infrastructure basic service set (BSS) mode may have an access point (AP) for a BSS and one or more stations (STA) associated with the AP. The AP may have access or an interface to a distribution system (DS) or another type of wired / wireless network that carries traffic to and / or carries traffic away from the BSS. Traffic originating from outside the BSS and leading to the STA may be reached by the AP and may be delivered to the STA. Traffic originating from the STA and leading to a target outside the BSS may be transmitted to the AP to be delivered to the corresponding target. Traffic between STAs within the BSS may be transmitted by the AP, for example, wherein the source STA may transmit traffic to the AP, and the AP may deliver traffic to the target STA. Traffic between STAs within the BSS may be considered and / or referred to as point-to-point traffic. Point-to-point traffic may be transmitted between the source STA and the target STA (e.g., directly between them) 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 within or using the IBSS (eg, all STAs in the STA) may communicate directly with each other. The IBSS communication mode may sometimes be referred to herein as an "ad hoc" communication mode.

[0061] When using the 802.11ac infrastructure operating mode or a similar operating mode, the AP may send beacons on a fixed channel (such as a primary channel). The primary channel may be a fixed width (e.g., a 20 MHz wide bandwidth) or a dynamically set width. The primary channel may be a working channel of the BSS and may be used by the STA to establish a connection with the AP. In certain representative embodiments, carrier sense multiple access / collision avoidance (CSMA / CA) may be implemented, for example, in an 802.11 system. For CSMA / CA, a STA (e.g., each STA) (including the AP) may listen to the primary channel. If the primary channel is listened / detected and / or determined to be busy by a particular STA, the particular STA may back off. One STA (e.g., only one station) may transmit at any given time in a given BSS.

[0062] High throughput (HT) STAs may communicate using a 40 MHz wide channel, for example, via a combination of a primary 20 MHz channel and adjacent or non-adjacent 20 MHz channels to form a 40 MHz wide channel.

[0063] Very high throughput (VHT) STA can support 20MHz, 40MHz, 80MHz and / or 160MHz wide channels. 40MHz channels and / or 80MHz channels can be formed by combining continuous 20MHz channels. 160MHz channels can be formed by combining 8 continuous 20MHz channels, or by combining two non-continuous 80MHz channels (this can be called 80+80 configuration). For 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 processed by inverse fast Fourier transform (IFFT) and time domain processing separately. These streams can be mapped to two 80MHz channels, and data can be sent by sending STA. At the receiver of the receiving STA, the above-mentioned operation for 80+80 configuration can be reversed, and the combined data can be transmitted to the medium access control (MAC).

[0064] 802.11af and 802.11ah support operating modes below 1GHz. Channel operating bandwidths and carriers are reduced in 802.11af and 802.11ah relative to those used in 802.11n and 802.11ac. 802.11af supports 5MHz, 10MHz, and 20MHz bandwidths in the TV White Space (TVWS) spectrum, and 802.11ah supports 1MHz, 2MHz, 4MHz, 8MHz, and 16MHz bandwidths using non-TVWS spectrum. According to a representative embodiment, 802.11ah may support meter type control / machine type communication (MTC), such as MTC devices in macro coverage areas. MTC devices may have certain capabilities, such as limited capabilities, including support for (e.g., only support for) certain bandwidths and / or limited bandwidths. MTC devices may include batteries with battery life above a threshold (e.g., to maintain very long battery life).

[0065] WLAN systems that can support multiple channels and channel bandwidths (such as 802.11n, 802.11ac, 802.11af, and 802.11ah) include channels that can be designated as primary channels. 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 a STA (which supports the minimum bandwidth operation mode) from all STAs operating in the BSS. 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 operation 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 operation mode) is transmitting to the AP, all available bands may be considered busy even if most of the available bands remain idle.

[0066] In the United States, the available frequency band for 802.11ah is 902MHz to 928MHz. In South Korea, the available frequency band is 917.5MHz to 923.5MHz. In Japan, the available frequency band is 916.5MHz to 927.5MHz. The total bandwidth available for 802.11ah is 6MHz to 26MHz, depending on the country code.

[0067] Figure 1D1 is a system diagram illustrating the RAN 104 and the CN 106 in accordance with an embodiment. As noted above, the RAN 104 may employ NR radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0068] The RAN 104 may include gNBs 180a, 180b, 180c, though it will be appreciated that the RAN 104 may include any number of gNBs while remaining consistent with an embodiment. The gNBs 180a, 180b, 180c may each 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 send signals to and / or receive signals from the gNBs 180a, 180b, 180c. Thus, the gNB 180a may, for example, use multiple antennas to send wireless signals to and / or receive wireless signals from the WTRU 102a. In one embodiment, the gNBs 180a, 180b, 180c may implement carrier aggregation technology. For example, the gNB 180a may transmit multiple component carriers to the 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 one embodiment, the gNBs 180a, 180b, 180c may implement coordinated multi-point (CoMP) technology. For example, the WTRU 102a may receive coordinated transmissions from the gNB 180a and gNB 180b (and / or gNB 180c).

[0069] The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using transmissions associated with parameter sets that may be scalable. 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 Transmission Time Intervals (TTIs) of varying or scalable lengths (e.g., containing varying numbers of OFDM symbols and / or varying absolute time lengths over time).

[0070] 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 while not accessing other RANs (e.g., such as the eNodeBs 160a, 160b, 160c). In a standalone configuration, the WTRUs 102a, 102b, 102c may use 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 gNB 180a, 180b, 180c while also communicating / connecting with another RAN, such as the eNode-B 160a, 160b, 160c. For example, the WTRUs 102a, 102b, 102c may implement the DC principle to communicate with one or more gNBs 180a, 180b, 180c and one or more eNode-Bs 160a, 160b, 160c substantially simultaneously. In a non-standalone configuration, the eNode-B 160a, 160b, 160c may act as a mobility anchor for the WTRUs 102a, 102b, 102c, and the gNB 180a, 180b, 180c may provide additional coverage and / or throughput for serving the WTRUs 102a, 102b, 102c.

[0071] Each of the gNBs 180a, 180b, 180c may be associated with a specific cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in UL and / or DL, support of network slicing, interworking between DC, NR, and E-UTRA, routing of user plane data towards a user plane function (UPF) 184a, 184b, routing of control plane information towards 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.

[0072] Figure 1D The illustrated CN 106 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 the aforementioned elements are depicted as part of the CN 106, it should be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0073] The AMF 182a, 182b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 104 via the N2 interface and may act as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRU 102a, 102b, 102c, support of network slicing (e.g., handling of different protocol data unit (PDU) sessions with different requirements), selecting a specific SMF 183a, 183b, management of registration areas, termination of non-access stratum (NAS) signaling, mobility management, etc. The AMF 182a, 182b may use network slicing in order to customize CN support for the WTRU 102a, 102b, 102c based on the type of services utilized by the WTRU 102a, 102b, 102c. For example, different network slices may 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. The AMF 182a, 182b may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as LTE, LTE-A, LTE-A Pro, and / or non-3GPP access technologies, such as WiFi.

[0074] The SMF 183a, 183b may be connected to the AMF 182a, 182b in the CN 106 via the N11 interface. The SMF 183a, 183b may also be connected to the UPF 184a, 184b in the CN 106 via the N4 interface. The SMF 183a, 183b may select and control the UPF 184a, 184b, and configure traffic 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 DL data notifications, etc. The PDU session type may be IP-based, non-IP-based, Ethernet-based, etc.

[0075] The UPF 184a, 184b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 104 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 DL packets, providing mobility anchoring, etc.

[0076] The CN 106 may facilitate communications with other networks. For example, the CN 106 may include or may communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that acts 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 networks and / or wireless networks owned and / or operated by other service providers. In one embodiment, the WTRUs 102a, 102b, 102c may be connected to the DNs 185a, 185b via the UPFs 184a, 184b via the N3 interfaces to the UPFs 184a, 184b and the N6 interfaces between the UPFs 184a, 184b and the local DNs 185a, 185b.

[0077] Given that Figures 1A to 1D as well as Figures 1A to 1D Corresponding to the description of the present invention, one or more or all of the functions described herein with reference to one or more of the following items may be performed by one or more simulation devices (not shown): WTRU102a-102d, base station 114a-114b, evolved Node B 160a-160c, MME 162, SGW 164, PGW 166, gNB 180a-180c, AMF 182a-182b, UPF 184a-184b, SMF 183a-183b, DN 185a-185b and / or any other device described herein. The simulation device may be one or more devices configured to mimic 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.

[0078] The simulation device may be designed to implement one or more tests of other devices in a laboratory environment and / or in an operator network environment. For example, one or more simulation devices may perform one or more functions 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 may perform one or more functions or all functions while being temporarily implemented / deployed as part of a wired and / or wireless communication network. The simulation device may be directly coupled to another device for the purpose of testing and / or performing tests using over-the-air wireless communications.

[0079] One or more simulation devices can perform one or more (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 laboratory and / or a non-deployed (e.g., testing) wired and / or wireless communication network to implement testing of one or more components. One or more simulation devices can be test equipment. Direct RF coupling and / or wireless communication via RF circuits (e.g., which may include one or more antennas) can be used by the simulation device to send and / or receive data.

[0080] In some cases of transmitting signals, non-ideal oscillators can produce signals that are impaired by random phase fluctuations, known as phase noise (PN). PN power increases with the square of the carrier frequency, which means that each doubling of the frequency results in a 6dB increase in PN power. Another important factor in phase noise is the way a given frequency is generated and multiplied to achieve the desired system / carrier frequency. Larger multiplication factors and more multiplications increase the phase noise generated in the carrier frequency. Therefore, THz frequencies and frequencies below THz may be more susceptible to PN problems than lower frequencies. This may be further aggravated by the immature oscillator technology currently available to generate such higher frequencies. Multi-carrier waveforms such as cyclic prefix-orthogonal frequency division multiplexing (CP-OFDM) or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) may be particularly susceptible to PN problems because these waveforms destroy the orthogonality of the subcarriers, thereby introducing inter-carrier interference (ICI).

[0081] Phase noise can cause several impairments to CP-OFDM and DFT-s-OFDM, such as the common phase error (CPE), which represents a constant phase shift applied to all subcarriers of the signal, albeit with small random fluctuations around its value. The CPE has high correlation in its value in the frequency domain, but has low correlation in the time domain due to its unpredictability. Another impairment to CP-OFDM and DFT-s-OFDM can be the ICI term caused by leakage of subcarriers to adjacent subcarriers due to loss of orthogonality, so that the complex amplitude of the subcarrier is contaminated by undesired contributions from adjacent subcarriers. For example, ICI can be the result of phase noise variations within a symbol.

[0082] In general, CPE may be an impairment at mmWave frequencies, and for such frequencies, the effects of ICI due to phase noise may be negligible by proper selection of subcarrier spacing and reference symbols. For this reason, industry advances (such as 5G NR or future releases) may wish to address CPE impairments and / or take specific steps to compensate for CPE impairments in mmWave frequencies or any frequency where improvements may be achieved using one or more of the techniques disclosed herein.

[0083] Figure 2 An example of PT-RS signal allocation in CP-OFDM 5G NR for DM-RS configuration type 1 (200) and type 2 (210) is illustrated. The horizontal axis depicts time and the vertical axis depicts frequency, thereby depicting the theoretical range in which a wireless signal can be transmitted in time and / or frequency. In one example, the time increment can be shown in symbols and the frequency increment can be shown in subcarriers. The impact of common phase error (CPE) can be handled by introducing a phase tracking reference signal (PT-RS) that is intended to correct the CPE term at the subcarriers of the received signal. Figure 2 An example of an arrangement of phase tracking reference signal (PT-RS) signals in cyclic prefix orthogonal frequency division multiplexing (CP-OFDM) for two demodulation reference signal (DM-RS) configurations (i.e., configuration type 1 (200) and type 2 (210)) is shown. CPE compensation may be considered necessary in frequency range 2 (FR2) to ensure good performance, especially at high order modulations. At 220, there is an example legend: squares with both left and right slanted lines represent PT-RS, squares with right slant are DM-RS (1), and squares with vertical lines are DM-RS (2) (e.g., two DM-RS, each with a different port). In one example, all empty squares may be no signal, data signal, or some other non-RS.

[0084] However, as carrier frequencies increase towards sub-THz bands, CPE alone may not be sufficient to avoid signal degradation. To this end, the subcarrier spacing may be increased to reduce the impact of ICI, and all relevant OFDM parameters are changed accordingly, resulting in different sets of parameters (e.g., in 5G NR) to cope with frequencies from below 1 GHz up to mmWave frequencies. However, above a certain carrier frequency, the subcarrier spacing needs to be so large that the cyclic prefix may no longer absorb the delay spread of the channel, or the shortened symbol duration may impair coverage beyond acceptable limits. This motivates the need to explicitly mitigate phase noise-induced ICI at sub-THz frequencies and at THz frequencies.

[0085] ICI may have a deeper impact on CP-OFDM than on DFT-s-OFDM, mainly because of one or more reasons: the higher time resolution allowed by the former to track phase noise variations within a symbol, and / or the additional frequency diversity introduced by the spread spectrum operation. In some cases, PN at carrier frequencies from 52.6 GHz to 71 GHz (FR2-2 frequencies) can be handled by new parameter sets and PT-RS enhancements to better cope with PN. However, further improvements may still be needed to handle the potential gains obtained from new PT-RS designs (e.g., for CP-OFDM or DFT-s-OFDM). In some cases, block-based PT-RS designs may be affected by the coherence bandwidth of the channel, and several PT-RS blocks may need to be allocated in a clustered manner to refine the phase noise estimate by averaging over the PT-RS blocks, where the spacing between clusters is determined by the delay spread of the channel. This can be demonstrated by simulation.

[0086] As technology advances, one or more issues associated with phase noise (PN) may exist in wireless systems. PN is a serious problem at very high frequencies, where its power grows with the square of the carrier frequency and cannot be avoided by front-end design alone. At frequencies below THz, PN-induced ICI dominates over CPE and may be more difficult to compensate due to the loss of orthogonality it creates across subcarriers. Increased subcarrier spacing can partially mitigate phase noise-induced ICI, but it may face limitations above certain frequencies because shorter cyclic prefixes are insufficient to support the delay spread of the channel and / or shortened symbol durations result in compromised coverage. In addition, for multiple devices with a wide range of capabilities, it may not be feasible to limit the system to a single very wide subcarrier spacing.

[0087] In addition, PN degradation may be more severe in CP-OFDM than in DFT-s-OFDM waveforms, mainly because the PT-RS design results in an estimated granularity based on one CP-OFDM symbol. ICI compensation based only on the receiving entity strategy (such as removing ICI or Wiener filter) has limited gain and may cause significant complexity to the actual receiving entity. For example, since CPE has a significant impact on ICI, such a receiving strategy is acceptable for FR2-2 systems. For systems below THz and THz systems, such designs may fail considering that PN increases with carrier frequency and oscillator efficiency decreases. Block-based PT-RS design can benefit from cluster arrangements, in which multiple PT-RS blocks are used to refine PN ICI estimates by averaging over these blocks. The number of PT-RS blocks and their relative frequency distances may depend on the coherence bandwidth of the channel, and the size of each PT-RS block depends on the width of the phase noise spectrum response. Therefore, there may be no single solution that can cope with all possible devices and channel characteristics.

[0088] Additionally, the coexistence of devices with widely varying capabilities and qualities in the same cell may lead to a PT-RS design based on worst-case scenarios, thereby considering the maximum possible phase noise spectrum width and the minimum possible coherence bandwidth of the channel. Such a design may result in significant overhead and resource inefficiency. Phase noise mitigation requirements may vary greatly depending on the reliability or performance requirements of the application, and there is no PN compensation scheme that can adapt to different applications or device characteristics.

[0089] In general, phase noise and / or related aspects of wireless systems need to be addressed in order to address one or more of the problems identified above and / or one or more problems that may exist in any wireless system. In order to better address PN-induced ICI impairments in CP-OFDM, there may be one or more methods for PN compensation in which multiple groups of reference symbols are sent by the following actions: dividing the allocated PRB calculation into groups of appropriate size (equal to or lower than the coherence bandwidth of the channel), and / or ensuring frequency-domain cyclic symmetric transmission from the transmitting entity side that adds cyclic subcarriers to each group. Such methods outline the selection of an appropriate number and size of groups to enable a suitable level of PN compensation at the receiving entity, and provide various methods to ensure cyclic symmetry within each group. These methods may also include mapping complex data symbols and reference signals to subcarriers in frequency-domain groups to help the receiving entity mitigate phase noise in a manner that better adapts to transceiver characteristics and channel conditions.

[0090] For the purpose of illustration, it may be assumed herein that CP-OFDM symbols are scheduled for transmission of one or several frequency multiplexed signals in a wireless communication system subject to phase noise. Transmissions to / from any given user (e.g., a given device) will include the M allocated to that user. a In the downlink of such wireless communication systems, the transmitted signal may address multiple users, each user comprising a different number of allocated subcarriers, which share the same time resource via frequency multiplexing or spatial multiplexing of complex modulation symbols. In the uplink, it may be assumed that the transmitted signal corresponding to a given user comprises M a The total system bandwidth will include N subcarriers, which corresponds to the discrete Fourier transform (DFT) or fast Fourier transform (FFT) size required to switch between the time domain and the frequency domain.

[0091] The phase noise impairment can be considered as a constant envelope multiplicative noise term e that varies randomly jθ[n] , this constant envelope multiplicative noise term affects the time domain samples x[n] in each CP-OFDM symbol. Assuming there are no other impairments from the channel or transceiver, the signal corrupted by phase noise can be written as follows:

[0092]

[0093] where θ[n] is a random phase noise term that includes phase impairments induced at the sender physical oscillator and the receiver physical oscillator, w[n] is an additive white Gaussian noise term, and X N [k] is the complex subcarrier amplitude of the signal in the frequency domain after the N-point DFT. The multiplication in the time domain can be viewed as a circular convolution in the frequency domain and can therefore be written as:

[0094]

[0095] in represents N-point circular convolution, and R N [k], P N [k] and W N [k] are the N-point DFTs of r[n], x[n], and w[n] respectively:

[0096]

[0097] However, if the allocated bandwidth is further divided into L subcarrier groups, each subcarrier group is of length M, and each group exhibits cyclicity in the frequency domain, the same convolution property can be maintained in each subcarrier group as follows:

[0098]

[0099] Where R M [k], P M [k] and W M [k] is the M-point DFT of r[n], x[n], and w[n], respectively. In this way, phase noise impairments can be analyzed in each subcarrier group of size M in the time domain by point-wise multiplication or in the frequency domain by circular convolution.

[0100] Using one or more of the above equations to analyze phase noise impairments may present one or more advantages, such as subcarrier groups may be processed separately to estimate and further compensate for phase noise ICI by using a smaller DFT for each subcarrier group, thereby reducing overall complexity.

[0101] Using one or more of the above equations to analyze phase noise impairments may have one or more advantages, such as, assuming that PN compensation is typically performed by a receiving entity after channel equalization, the residual equalization error may be different in each subcarrier group depending on the value of the coherence bandwidth of the channel. Therefore, it is desirable to estimate the phase noise separately in each subcarrier group to avoid the influence of residual errors from another frequency region with a very different channel response. Further averaging the estimates over the subcarrier group may improve frequency diversity during the PN compensation process. The size M of the subcarrier group should be equal to or less than the coherence bandwidth of the channel in order to benefit from frequency diversity when averaging the estimates over the subcarrier group. The coherence bandwidth of the channel may be assumed to be known via channel state information (CSI) feedback or direct estimation by the transmitting entity when channel reciprocity is ensured (e.g., as in a time division duplex TDD system using the same carrier frequency for uplink and downlink).

[0102] Using one or more of the above equations to analyze phase noise impairments may present one or more advantages, such as, CPE estimation may exploit the presence of legacy PT-RS signals potentially inserted into the WTRU's allocated bandwidth. When PN-induced ICI is significant, the PT-RS signal may be assumed to be present in every CP-OFDM symbol to track CPE variations due to low temporal coherence of phase noise.

[0103] Signals in the frequency domain may generally be non-cyclic unless an appropriate frequency domain cyclic structure (cyclic prefix or cyclic suffix (or both)) is appended or prepended to the subcarrier group, resulting in the cyclic partitioning method shown herein, such as Figure 3 as shown in .

[0104] Figure 3 An example of a cyclic partition is illustrated, where frequency 350 is shown on the horizontal axis. 300 shows the M a301, and non-limiting examples of signals (eg, PT-RS 302, DM-RS 303, PDSCH / PUSCH 304). Moving 309 to the bottom of the diagram, at 310, there may be M a The subcarriers 301 (e.g., the allocated bandwidth of the WTRU) are cyclically divided into L subcarrier groups (e.g., subcarrier group #0 311 to subcarrier group #L-1 312), where a frequency domain cyclic prefix / cyclic suffix (FD-CP, FD-CS) structure (e.g., FD-CP 314, FD-CS 315) is prepended and postpended to each of these subcarrier groups, respectively. The details of the FD-CP / CS insertion in each subcarrier group are described in Figure 4 exemplified in.

[0105] Figure 4 An example of FD-CP / CS insertion in a subcarrier group is illustrated. As shown at 400, there is a first group of subcarriers 412, where frequency 450 is shown in the horizontal axis. For maximum generality, a frequency domain cyclic prefix (FD-CP) 414 and / or a frequency domain cyclic suffix (FD-CS) 415 may be pre-pended / post-pended to the subcarrier group to achieve signal cyclicity. The signal within the subcarrier may be data, PT-RS, DM-RS, etc. (e.g., 419). In actual situations, one FD-CP, one FD-CS, or a combined FD-CP / CS may be preferred. The FD-CP may include the last L in the subcarrier group. CP subcarriers, and the FD-CS may contain the first L CS The subcarrier group size M can be less than or equal to the coherence bandwidth B of the channel. coh The length of the frequency domain cyclic prefix is ​​L CP 416 and the length of the frequency domain cyclic suffix L CS 417 may be greater than or equal to a function of the phase noise spectrum width.

[0106] Figure 5 An example of a phase noise response is illustrated, which shows a single-sided spectrum width of -120 dBc / Hz power spectral density. As shown in 500, frequency is shown on the horizontal axis 550, and phase noise is shown on the vertical axis 551. CP and L CS Both can be used together Figure 5 The spectral width of the phase noise response observed in the entire transmit / receive transceiver chain is related to the single-sided or double-sided spectral width shown in , as described in the following subsections. PN It can represent the single-sided spectral width of a given level of phase noise, so the double-sided spectral width of phase noise can be 2Δf PN For simplicity and without intending to limit any disclosure, only Δf may be considered with respect to the subcarrier spacing.PN and 2Δf PN The relative value of .

[0107] for Figure 6 , Figure 7 and Figure 8 , where frequency is shown on the horizontal axis. M may represent the region size (eg, 613, 713, and 813).

[0108] Figure 6 An example of a single FD-CP insertion per subcarrier group is illustrated. In this case, the size is L CP ≥2Δf PN A single FD-CP 614 (relative to the subcarrier spacing) may cause the subcarrier groups to appear cyclic, such as Figure 6 The subcarriers in the region of size M 613 (including the shaded region at the end) may contain data, PT-RS, DM-RS (e.g., 619), or any other control / data signal foreseen to be mapped in this region. In some cases, the length L CP 616 may be small even at very high frequencies, on the order of less than a factor of 10. The CPE may correspond to the DC component of P[k], such as P[0].

[0109] For a subcarrier group that handles both positive and negative frequency offsets caused by phase noise, the DFT window 661 for PN compensation may start at the center of the FD-CP 614 and be Δf before the end of the CP-OFDM symbol. PN In view of this, the control / data subcarriers originally scheduled in the subcarrier group can be cyclically shifted right by L in the DFT window. CP / 2 subcarriers (eg, see arrows), and this can be taken into account by the phase noise compensation algorithm.

[0110] Figure 7 An example of a single frequency domain cyclic suffix (FD-CS) 715 insertion for each subcarrier group is shown. In this case, the frequency domain cyclic suffix FD-CS 715 can perform the same as Figure 6 The same role as shown for FD-CP (e.g. Figure 6 A similar description applies to Figure 7 ). The size of FD-CS 715 must satisfy the condition L CS ≥2Δf PN (relative to the subcarrier spacing) to obtain cyclicity, and the control / data subcarrier 719 originally scheduled in the subcarrier group may be cyclically shifted left by L in the DFT window. CP / 2 subcarriers (eg, see arrows).

[0111] The advantage of using a single FD-CP or FD-CS is its similarity to the known CP insertion technique employed in CP-OFDM, at the expense of a cyclic shift (half the length of the FD-CP or FD-CS) in the control / data information contained in the DFT window (e.g., 661, 761). However, since PN compensation is performed after channel equalization, in some cases, this shift does not affect performance as long as the PN compensation takes into account the correct subcarrier ordering.

[0112] Figure 8 An example of combined FD-CP / CS insertion per subcarrier group is illustrated. This includes the more general case where both FD-CP 814 and FD-CS 815 are respectively post- and pre-pended to a subcarrier group (e.g., M 813), such as Figure 8 Assuming a symmetrical phase noise response, the FD-CP / CS must satisfy the condition (relative to the subcarrier spacing): L CP =L CS ≥Δf PN The advantage of this case is that no reordering is required when performing PN compensation in each subcarrier group, and the DFT window 861 contains the original subcarriers without shifting.

[0113] Without loss of generality, the examples disclosed herein may involve inserting FD-CP / CS generally into a subcarrier group corresponding to a single FD-CP, a single FD-CS, or a combined FD-CP / CS, depending on the specific implementation. The length of the FD-CP, FD-CS, and the size M may be adapted per WTRU to the phase noise and channel conditions in the relevant portion of the carrier bandwidth.

[0114] The single-sided or double-sided spectral width of the phase noise may be predetermined by the transceiver or reported by the receiving entity. The phase noise spectral width will typically represent the combined PN characteristics of the transmitting entity oscillator and the receiving entity oscillator.

[0115] Fig. 9 An example of a transmit process for generating a CP-OFDM signal based on phase noise cycle partitioning is illustrated. To illustrate one or more of the techniques disclosed herein, Fig. 9The process for transmitting a CP-OFDM signal based on phase noise cyclic partitioning is illustrated in an example of . Conventional (e.g., traditional) processing for generating a CP-OFDM signal may be depicted in a shaded box (e.g., 921), while a new or modified box may be depicted in a box without any fill (e.g., 922). The transmitting steps may focus on generating a CP-OFDM signal for a given WTRU, but all explanations may be extended to the case of multiple WTRUs frequency multiplexed in the same CP-OFDM symbol. Transmission may also be based on a single transmit receive point (TRP), but the techniques disclosed herein may be applied to the case of having multiple TRPs as exemplified herein. As discussed herein, one or more TRPs may be part of a base station.

[0116] As disclosed herein (eg, below), techniques for generating CP-OFDM symbols based on disclosed examples of the phase noise cycle partitioning method described herein may be required in a processing step.

[0117] like Fig. 9 As shown, the data bits may go to FEC encoding 901 and produce one or more symbols. In the example, each symbol will be processed separately. For FD-CP / CS / M selection 902, the box performs a selection of the length of the FD-CP field and / or the FD-CS field and the size M of the subcarrier group. The FD-CP / CS / M selection may follow the criteria explained herein (e.g., the phase noise cyclic partitioning method), that is, M may be equal to or less than the coherence bandwidth of the channel experienced by the WTRU, and the length of the FD-CP and / or FD-CS should meet any of the criteria stated in this example or other examples herein (e.g., single FD-CP insertion per subcarrier group, single FD-CS insertion per subcarrier group, combined FD-CP / CS insertion per subcarrier group). If the coherence bandwidth of the channel is greater than the allocated bandwidth of the WTRU, the transmitting entity may decide not to perform phase noise cyclic partitioning because the benefit of having FD-CP or FD-CS in this case will disappear (e.g., and the receiving entity may perform ICI compensation based on the specific implementation without any changes to the transmitted signal). Otherwise, the block generates the number of subcarrier groups, their size M, and the length of the FD-CP field and / or the FD-CS field for use by the transmitting entity.

[0118] The values ​​of M and the length of the FD-CP and / or FD-CS may be selected from allowed combinations in a codebook of a priori defined values, which the transmitting and receiving entities may know in advance to appropriately account for any expected phase noise characteristics and channel coherence bandwidth.

[0119] A factor that affects phase noise may be the quality of the oscillators at the sender device and at the receiver device. In some cases, as disclosed herein, this factor may be important relative to other factors. More precisely, the entire process of oscillator, phase-locked loop, and carrier generation may have an impact on phase noise, although the term "oscillator quality" is used for the sake of illustration. The sender entity may know the quality of its oscillator, but may not have information about the receiver entity's oscillator. In some cases, although the knowledge of the actual oscillator quality allows the sender entity to appropriately select a set of parameters for PN compensation to achieve a trade-off between overhead and performance, there may be some minimum requirements to be met.

[0120] The selection may be based on channel state information and / or any known PN information of the transmit-receive link, including, for example, the PN spectrum width or PN capability of the receiving entity. The PN information may be obtained from feedback reports transmitted by the receiving entity, or the PN information may be obtained by measurements performed by the transmitting entity on signals received from a peer node in the opposite link direction, such as if / when the receiving entity acts as the transmitting entity. Assuming that the PN is the result of combined impairments from the transmit and receive RF chains, the characteristics of the PN on the downlink or uplink may be inferred as long as the same transmit / receive node pair is considered in each case.

[0121] The rules for selecting FD-CP / CS / M may be based on a semi-static PN configuration message received by high-layer signaling, or based on a dynamic strategy that depends on received feedback and / or is triggered by a specific event previously configured by high-layer signaling. The selection may also take into account the overhead caused by the FD-CP / CS field to minimize its impact on available resources.

[0122] In order to better react to the phase noise experienced by the receiving entity, the transmitting entity may take into account the indication received from the peer entity, which notifies about the high phase noise received, which may, for example, trigger an increase in the FD-CP length and / or the FD-CS length to better absorb the ICI. Such an indication may be transmitted by the receiving entity in an uplink shared control or data channel (e.g., 5G NR PUCCH or PUSCH) or by means of a medium access control (MAC) control element (CE) MAC CE. The indication may be based on a phase noise ICI power exceeding a threshold, which is set via higher layer signaling or configured by the transmitting entity in a phase noise configuration message, such as in a downlink shared control or data channel (e.g., PDCCH or PDSCH) or by means of a MAC CE.

[0123] The CSI information may include any indication of the channel quality measured by the receiving entity and reported back to the sending entity, such as channel quality indicator (CQI) information for each subband, signal-to-noise ratio (SNR), or explicit measurement results of the coherence bandwidth of the channel. When the channel reciprocity condition is met (e.g., when the downlink carrier frequency and the uplink carrier frequency are the same, such as in a TDD system), the sending entity may also obtain CSI by measurements performed in the opposite link direction.

[0124] The PN information may include, but is not limited to, any of the following metrics (in any suitable units or according to any predefined quantization scale): an indication of the phase noise spectral width (e.g., in Hz or number of subcarriers); an indication of the number of non-negligible ICI coefficients that describe the phase noise under current operating conditions; the power of the experienced phase noise impairment; an indication of the post-detection SNR measured at the receiving entity after equalization and phase noise compensation; the residual mean square error (MSE) of the detection at the output of the phase noise compensation algorithm; and / or the error vector magnitude (EVM) of the constellation seen at the receiving entity after equalization.

[0125] Other measurements are also contemplated without departing from the concepts contained in the examples provided herein.

[0126] Any PN information reported by the receiving entity may be transmitted in a periodic, semi-periodic, on-demand or event-triggered manner. Some of the above PN information may be inferred by the transmitting entity from measurements performed in the opposite link direction (such as the phase noise spectrum width or the number of non-negligible ICI coefficients describing the phase noise).

[0127] Information about the PN capabilities of the receiving entity may be obtained with the aid of feedback transmitted by the receiving entity node at session establishment. The PN capabilities may include, for example, the radio frequency class or oscillator quality level, or an indication of the amount of phase noise that the receiving device is expected to experience under typical operating conditions (e.g., temperature, power, or cell load), measured in terms of phase noise spectrum width, the number of non-negligible ICI coefficients that characterize the phase noise of a given parameter set or set of parameter sets, or any other similar information. The PN capabilities may also be obtained from higher layer signaling in a static or dynamic manner depending on the application requirements, or retrieved from a database storing the phase noise characteristics of the receiving entity.

[0128] In the FD-CP / CS / M selection box 902, L is obtained CP , L CS and the selected value of M, Fig. 9 The rate matching block 903 in the example shown in FIG. 1 may be configured to take into account the overhead caused by FD-CP and / or FD-CS (calculated as o=(L CP +L CS) / M) and the overhead caused by any other control and reference signals. The rate matching block may operate after the forward error correction (FEC) encoding block 901 (which is intended to provide redundancy to the information to improve resilience to channel impairments) and adjusts the amount of parity information at its output to match the available physical resources in the CP-OFDM symbol.

[0129] After modulating 904 the rate-matched data bits to complex constellation symbols and performing serial-to-parallel (S / P) conversion 905, the subcarrier partitioning block 906 may take as input the complex control and data symbols to be mapped onto the physical resources and convert the subcarriers of size M a The entire set of is divided into one or more subcarrier groups, each of length M. Control and reference signals should be included in the useful part of the subcarrier group with length M, including, for example, PT-RS and / or DM-RS from 5G NR. Afterwards, the FD-CP 907 field and the FD-CS 909 field, containing copies of the last or first few complex symbols, respectively, may be prepended or postpended to each subcarrier group in order to maintain cyclicity in the frequency domain and allow DFT-based PN compensation for each subcarrier group.

[0130] The remaining steps for transmission may include: an inverse FFT 910 of size N to generate a time domain signal s T [n]; parallel-to-serial (P / S) conversion 911; and / or adding a time domain cyclic prefix to absorb the multipath caused by the delay spread of the channel, thereby providing signal circularity in the time domain.

[0131] The sending entity may signal 912 to the receiving entity an indication of the length of the FD-CP and / or FD-CS and the value of M employed in one or several consecutive CP-OFDM symbols. A single FD-CP / CS / M indication including the required parameters may be transmitted, or several separate indications may also contain the corresponding parameters, depending on the specific implementation. The sending entity may transmit 912 an index corresponding to a predefined codebook containing all possible combinations of FD-CP length and / or FD-CS length and the value of M, so that the receiving entity may unambiguously obtain the selected parameters. Blind detection of these parameters may also be performed by the receiving entity to avoid explicit signaling of these parameters.

[0132] In a compatible design, the network may configure a mapping table where each row provides an appropriate combination of parameter sets, i.e., length / M of FD-CP / CS. The network selects the appropriate configuration for PN compensation at the receiving entity and indicates its row index to the WTRU. Pre-configuration may indicate to the WTRU whether the indication for the PN parameter set is dynamic or static. For the dynamic case, an indication of the selected configuration may be sent in each DCI, providing great flexibility and responsiveness to adapt the system and transmission parameters. For the static or semi-static case, the PN parameter set indication may be provided as part of the Radio Resource Control (RRC) signaling or MAC-CE.

[0133] The WTRU may use the same mechanism and mapping structure to provide feedback to the network regarding the set of parameters it would like to receive for its PN compensation.The WTRU may provide an indication of its desired set of PN parameters as part of higher layer signaling.

[0134] The signaling indication may be transmitted periodically, semi-periodically, on demand, or triggered by an event such as a change in the coherence bandwidth of the channel, or if the phase noise conditions in the transmit / receive chain change significantly.

[0135] Fig.10 An example process for receiving a CP-OFDM signal based on phase noise cyclic partitioning is illustrated. The processing steps for receiving a CP-OFDM signal based on phase noise cyclic partitioning may be performed in Fig.10 . Without loss of generality, it may be assumed that the signal is received from a single TRP, but the explanation can be easily applied to the case of multiple TRPs, as described herein. The reception steps may be focused on a given WTRU, but all explanations can be easily extended to the case of multiple WTRUs frequency multiplexed in the same CP-OFDM symbol. Note that in Fig.10 In the example of , conventional (eg, traditional) processing of a signal may be depicted in a shaded box (eg, 1021 ), while a new or modified box may be depicted in a box without any fill (eg, 1022 ).

[0136] Symbols may be received 1001 and after serial-to-parallel conversion 1002 and performing an N-point FFT 1003, the received symbols may be equalized after channel estimation 1004 with the assistance of, for example, a DM-RS signal (e.g., in 5G NR). CPE compensation 1005 may then be performed with the assistance of, for example, a PT-RS signal in 5G NR, and the subcarriers may be de-partitioned 1006 by concatenating M subcarrier groups and removing the FD-CP field and / or the FD-CS field. The length L CP , L CSand M may be assumed to be obtained via signaling from the transmitting entity side, high-layer indication, or by blind detection. The signaling from the transmitting entity may be referred to as a predefined codebook, which contains all possible combinations of FD-CP length and / or FD-CS length and M values, so that the receiving entity may unambiguously obtain the selected parameters.

[0137] At the output of this block, the contents of the M useful subcarriers in each subcarrier group may be delivered to a PN Remove ICI block 1007 for ICI compensation.

[0138] With respect to the phase noise removal ICI block 1007, the block may exploit signal cyclicity by performing estimation and subsequent elimination of phase noise ICI impairments separately for each of the subcarrier groups, and further averaging over the subcarrier groups to achieve additional frequency diversity. Measurement of the residual phase noise power after the removal ICI process may be performed to assess, for example, whether there is high phase noise, so that the transmitting entity performs corrective actions to further reduce the phase noise. For example, if the residual phase noise power exceeds a threshold, the receiving entity may transmit an indication to the transmitting entity that signals high phase noise and contains some phase noise related information, such as phase noise spectrum width, the number of non-negligible ICI coefficients of the phase noise response, post-detection SNR, residual MSE of the detection after ICI mitigation, EVM of the constellation after equalization, and / or similar information.

[0139] As an example of an ICI removal algorithm, the receiving entity may follow one or more steps to perform PN-induced ICI compensation.

[0140] First, the device can perform equalization and CPE compensation on the received signal to generate complex symbols in the frequency domain These symbols may typically suffer from phase noise induced ICI.

[0141] Second, the device can obtain L through signaling or blind detection. CP , L CS and M, take the lth group of M subcarriers, and discard the FD-CP / CS field to generate the symbol in the lth subcarrier group and its time domain counterpart

[0142] Third, assuming that the l-th subcarrier group symbol has been obtained in the previous iteration There may be one or more additional steps for ICI compensation. The device may demodulate The data symbols in , and a hard decision estimate is obtained by approximating the closest constellation symbol The device can reconstruct the M-point time domain signal The device estimates the time domain phase noise impairment by performing a point-by-point division of the time domain received signal and the reconstructed signal. The device can obtain phase noise figure and truncated to (at most) L by setting the remaining terms to zero CP +L CS +1 item. The device can remove ICI by performing M-point circular deconvolution to produce where amod b is the modulo operation that produces the remainder of the division a / b. The device calculates the RMS residual phase noise And repeat one or more of the previous steps until the RMS is below a predetermined threshold ε. In this case, take As an estimate of the ICI coefficient in the lth subcarrier group.

[0143] Fourth, the second and third steps may be repeated for each subcarrier group, after undoing any residual CPE that may remain after equalization, averaging the ICI coefficients in all subcarrier groups and scaling their magnitude to N, yielding:

[0144]

[0145] CPE res,l represents the residual phase at subcarrier group l. This term can be estimated, for example, based on the residual phase of the DC component in the lth phase noise response, The total residual CPE may then be further estimated across the subcarrier groups and compensated as in the first step.

[0146] Fifth, the device can be and The PN compensation signal is obtained by performing N-point circular convolution, that is,

[0147] The above example process is only an example of an ICI compensation algorithm, and other possibilities exist depending on the specific implementation. deICI (measured in terms of the number of complex multiplications) is given by:

[0148]

[0149] where f QAM (·) represents the hard decision function, N it is the number of iterations, M a is the number of subcarriers scheduled for the WTRU, Δf PN is the single-sided spectrum width of the phase noise, and represents f QAM complexity.

[0150] like Fig.10 As shown in the example of , after the parallel-to-serial conversion 1008 and demodulation 1009 of the subcarrier data, the rate matching operation performed at the sender can be undone 1010 to recover the original bits. CP , L CS The rate matching operation is aided by an indication of M and M. The output of block 1010 includes the received coded bits, which are then FEC decoded 1011 to recover the original information bits (eg, data bits).

[0151] In addition to the CSI information, the receiving entity may also report 1012 to the sending entity information about the amount of phase noise experienced in the detection, including, for example, an indication of a high phase noise channel condition, some phase noise related metrics (e.g., phase noise spectral width, the number of non-negligible ICI coefficients of the phase noise response, post-detection SNR or detected residual MSE), and a phase noise capability report. These metrics may be transmitted in a periodic, semi-periodic, on-demand, or event-triggered manner. Event-triggered reporting may be based on one or more conditions to be met upon reception, such as a residual phase noise ICI power being above a predetermined threshold, which may be configured via high-layer signaling or in a phase noise configuration information message transmitted by the sending entity. Periodic, semi-periodic, or on-demand reporting may also be based on a phase noise configuration received via high-layer signaling or in a phase noise configuration information message transmitted by the sending entity.

[0152] The phase noise capabilities of the receiving entity may include, for example, the RF class or oscillator quality grade, or an indication of the amount of phase noise expected to be experienced under typical operating conditions (e.g., temperature, power, or cell load), measured in terms of the phase noise spectral width, the number of non-negligible ICI coefficients that characterize the phase noise for a given parameter set or set of parameter sets, or any other similar information.

[0153] Fig.11 An example procedure for transmitting CP-OFDM symbols based on phase noise cycle partitioning is illustrated. In the illustrated example method, a first WTRU or a set of first WTRUs transmitting a CP-OFDM symbol to a second WTRU or a set of second WTRUs may perform one or more of the following actions: At 1101, obtain phase noise information (e.g., phase noise capability or phase noise spectrum width Δf) characterizing an amount of phase noise experienced in a communication link. PN ); At 1102, determine the coherence bandwidth B of the channel coh At 1103, based on B coh and phase noise information to select the subcarrier group size M, the length of the frequency domain cyclic prefix L CPand the length L of the frequency domain cyclic suffix CS At 1104, whether the coherence bandwidth of the channel is lower than the allocated bandwidth of the WTRU so that the cyclic partitioning parameters M, L CP and L CS Adapt to the instantaneous situation, and / or at 1105, determine whether the second WTRU reports a high phase noise indication; at 1106 (e.g., if 1104 and 1105 are "yes"), update L based on the high phase noise indication received from the second WTRU CP and L CS At 1107, a rate matching function is performed to adjust the amount of data to be mapped to the available physical resources after considering the frequency domain cyclic prefix and / or cyclic suffix field; at 1108, the subcarrier is divided into M subcarrier groups, and the frequency domain cyclic prefix and / or cyclic suffix is ​​post-pended / prepended to each subcarrier group; at 1109, a data packet containing M, L CP and L CS and / or at 1110, a CP-OFDM symbol is sent. If the result at 1104 is "no", a rate matching function is performed at 1111 without considering any overhead from cyclic partitioning; at 1112, the information is mapped to subcarriers without cyclic partitioning, and then 1109 is entered to transmit signaling information as disclosed herein. At 1105, if there is no high PN indication, the WTRU directly continues to perform the rate matching function at 1107.

[0154] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, phase noise information may be obtained / transmitted via higher layer signaling (eg, via RRC phase noise configuration information).

[0155] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, the phase noise information may be obtained from an indication transmitted by the second WTRU via, for example, an uplink shared control or data channel (e.g., PUCCH or PUSCH) or by means of a MAC CE.

[0156] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13) In one example of the transmission procedure described in the present invention, phase noise information may be obtained by a first WTRU or a set of first WTRUs by measuring the amount of phase noise experienced in an opposite link direction between the first WTRU or a set of first WTRUs and a second WTRU or a set of second WTRUs.

[0157] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one instance of the transmission procedure described in the present invention, the phase noise information may include an indication from the second WTRU or a set of second WTRUs containing the length of the frequency domain cyclic prefix and cyclic suffix and the subcarrier group size to be used by the first WTRU or a set of first WTRUs in the next CP-OFDM symbol or set of CP-OFDM symbols.

[0158] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described in the present invention, the phase noise information may include an indication from the second WTRU or the set of second WTRUs, the indication including the preferred subcarrier partitioning, the indication being an index into a codebook of a priori defined combinations of lengths of frequency domain cyclic prefix and cyclic suffix and subcarrier group sizes, which are known to the first WTRU or the set of first WTRUs and the second WTRU or the set of second WTRUs.

[0159] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of a transmit procedure described herein, the phase noise capability may include an indication of an a priori known RF class or oscillator quality class within a set of a priori classes or classes, or an indication of the amount of phase noise experienced under typical operating conditions (e.g., temperature, power, and / or cell load).

[0160] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of a transmission procedure described herein, the phase noise amount may be expressed as a phase noise spectral width measured in Hz or number of subcarriers for a given parameter set or set of parameter sets.

[0161] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13) in one example of a transmission procedure described herein, the phase noise amount may be expressed as the number of ICI coefficients that are not negligible in the phase noise spectrum response under current operating conditions.

[0162] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of a transmission procedure described herein, the amount of phase noise may be expressed as the power of the experienced phase noise impairment in watts, milliwatts, dBW, dBm, or any other suitable units.

[0163] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of a transmission procedure described herein, the amount of phase noise may be represented as an indication of a post-detection signal-to-noise ratio measured at a receiving entity after equalization and phase noise compensation.

[0164] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of a transmission procedure described herein, the amount of phase noise may be expressed as a detected residual mean square error at the output of a phase noise compensation algorithm.

[0165] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of a transmission procedure described in the context of FIG. 1 , the amount of phase noise may be expressed as the error vector magnitude of the constellation as seen at the receiving entity after equalization.

[0166] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described in , the high phase noise indication may be reported by the second WTRU in an uplink shared control or data channel (e.g., PUCCH or PUSCH), or by means of a MAC CE.

[0167] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13) in one instance of the transmission procedure described in the present invention, a high phase noise indication may be reported by a second WTRU based on a phase noise threshold transmitted by a first WTRU or a set of first WTRUs in a phase noise configuration message (e.g., in a downlink shared control or data channel (PDCCH or PDSCH), or by means of a MAC CE).

[0168] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, the coherent bandwidth of the channel may be obtained from a channel state information indication reported by the second WTRU, or may be measured by the first WTRU or a set of first WTRUs on a signal received from the second WTRU when the uplink carrier frequency and the downlink carrier frequency are the same.

[0169] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described in the accompanying drawings, the subcarrier group size M may be equal to or lower than the coherence bandwidth of the channel.

[0170] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, the frequency domain cyclic prefix includes the last L in each subcarrier group CP The complex subcarrier amplitudes are prepended to provide signal cyclicity in the frequency domain.

[0171] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, the frequency domain cyclic suffix includes the first L in each subcarrier group CS The complex subcarrier amplitudes are appended to provide signal cyclicity in the frequency domain.

[0172] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, the length of the frequency domain cyclic prefix can be zero, and the length of the frequency domain cyclic suffix can be equal to the double-sided phase noise spectrum width expressed in the number of subcarriers.

[0173] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, the length of the frequency domain cyclic suffix can be zero, and the length of the frequency domain cyclic prefix can be equal to the double-sided phase noise spectrum width expressed in the number of subcarriers.

[0174] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) In one example of the transmission procedure described, the length of the frequency-domain cyclic prefix and the length of the frequency-domain cyclic suffix may both be equal to the single-sided phase noise spectrum width expressed in terms of the number of subcarriers.

[0175] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described in the present invention, when calculating the amount of data information that can be mapped to the physically available resources after forward error correction coding, the rate matching function can take into account the overhead caused by the frequency domain cyclic prefix and / or the frequency domain cyclic suffix.

[0176] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, the signaling information may include an indication of the length of the frequency domain cyclic prefix and cyclic suffix and the subcarrier group size to be used in the next CP-OFDM symbol or CP-OFDM symbol set.

[0177] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, the signaling information may include an index into a codebook of a priori defined combinations of lengths of the frequency domain cyclic prefix and cyclic suffix and subcarrier group sizes that must be known to the first WTRU or a set of first WTRUs and the second WTRU or a set of second WTRUs for unambiguous detection.

[0178] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13) in one example of the transmission procedure described, signaling information may be transmitted by a first WTRU or a set of first WTRUs in a periodic, semi-periodic, on-demand, or event-based manner, where the periodicity is obtained via higher layer signaling or received from a second WTRU or a set of second WTRUs in a phase noise configuration message (via (e.g., a downlink shared control or data channel (PDCCH or PDSCH) or a MAC CE)).

[0179] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, the event for triggering the signaling information may be based on, for example, a change in the coherence bandwidth of the channel above a first threshold or a change in the phase noise spectrum width above a second threshold.

[0180] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) In one example of the transmission procedure described, in a downlink of a wireless communication system, the first WTRU is a base station equipment and the second WTRU is a UE.

[0181] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 )In one example of the transmission procedure described, the set of first WTRUs is a plurality of transmission and reception points in a downlink of a multi-TRP wireless communication system.

[0182] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 )In one example of the transmission procedure described, the first WTRU and the second WTRU are UEs in a side link of a wireless communication system.

[0183] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) In one example of the transmission procedure described, in an uplink of a wireless communication system, the first WTRU is a UE and the second WTRU is a base station equipment.

[0184] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13)In one instance of the transmission procedure described, the second set of WTRUs is a plurality of transmit and receive points in the uplink of a multi-TRP wireless communication system.

[0185] Fig.12 An example procedure for transmitting CP-OFDM symbols based on phase noise cycle partitioning is illustrated. In this example, a first WTRU or a set of first WTRUs transmitting CP-OFDM symbols to a second WTRU or a set of second WTRUs may perform one or more of the following actions: Initially, at 1201, the first WTRU may obtain / select default phase noise mitigation parameters (e.g., M, L CP and L CS ); At 1202, the first WTRU may select a default phase noise mitigation parameter (such as a subcarrier group size M, a length of a frequency domain cyclic prefix L CP and the length L of the frequency domain cyclic suffix CS The first WTRU may initiate one or more transmissions to one or more second WTRUs (e.g., a default value of a first WTRU); at 1203, the first WTRU may receive a phase noise report from the second WTRU, the phase noise report including any one of a high phase noise indication and an indication that the coherence bandwidth of the channel is lower than the allocated bandwidth of the second WTRU; at 1204, the first WTRU may adjust the cycle partitioning parameters M, L based on the phase noise report received from the second WTRU (e.g., a high phase noise indication). CP and L CS Adapt to the instantaneous situation; at 1205, the first WTRU may perform a rate matching function to divide the subcarriers into M subcarrier groups and append / prepend a frequency domain cyclic suffix / prefix to each subcarrier group; at 1206, the first WTRU may send updated parameters, such as transmitting a message including parameters (such as M, L CP and L CS value); and / or at 1207, the first WTRU may send a CP-OFDM symbol based on the updated phase noise mitigation parameter.

[0186] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of a transmission procedure described in the present invention, wherein the phase noise report may include an indication from a second WTRU or a set of second WTRUs containing the length of the frequency domain cyclic prefix and cyclic suffix and the subcarrier group size to be used by the first WTRU or the set of first WTRUs in the next CP-OFDM symbol or set of CP-OFDM symbols.

[0187] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described in the present invention, the phase noise report may include an indication from the second WTRU or the set of second WTRUs, the indication including a preferred subcarrier partitioning, the indication being achieved by indexing into a codebook of a priori defined combinations of lengths of frequency domain cyclic prefix and cyclic suffix and subcarrier group sizes, which are known to the first WTRU or the set of first WTRUs and the second WTRU or the set of second WTRUs.

[0188] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described in , the high phase noise indication may be reported by the second WTRU in an uplink control or shared data channel (e.g., PUCCH or PUSCH), or by means of a MAC CE.

[0189] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one instance of the transmission procedure described in the present invention, a high phase noise indication may be reported by a second WTRU based on a phase noise threshold transmitted by a first WTRU or a set of first WTRUs in a phase noise configuration message (such as, in a downlink control or shared data channel (PDCCH or PDSCH), or by means of a MAC CE).

[0190] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described in the accompanying drawings, the subcarrier group size M may be equal to or lower than the coherence bandwidth of the channel.

[0191] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, the frequency domain cyclic prefix includes the last L in each subcarrier group. CP subcarriers, which are prepended to provide signal cyclicity in the frequency domain.

[0192] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, the frequency domain cyclic suffix includes the first L in each subcarrier group CSThe complex values ​​associated with each subcarrier are appended to provide signal cyclicity in the frequency domain.

[0193] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, the length of the frequency domain cyclic prefix can be zero, and the length of the frequency domain cyclic suffix can be equal to the double-sided phase noise spectrum width expressed in the number of subcarriers.

[0194] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, the length of the frequency domain cyclic suffix can be zero, and the length of the frequency domain cyclic prefix can be equal to the double-sided phase noise spectrum width expressed in the number of subcarriers.

[0195] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) In one example of the transmission procedure described, the length of the frequency-domain cyclic prefix and the length of the frequency-domain cyclic suffix may both be equal to the single-sided phase noise spectrum width expressed in terms of the number of subcarriers.

[0196] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one instance of the transmission procedure described, a rate matching function is used to adjust the amount of data to be mapped to the available physical resources after taking into account the frequency domain cyclic prefix and / or cyclic suffix fields.

[0197] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ), a first WTRU or a set of first WTRUs transmits control signaling information including an indication of adaptation of a phase noise mitigation parameter, an updated value of a subcarrier group size (M), a length of a frequency domain cyclic prefix (L CP ) and the updated value of the frequency domain cyclic suffix length (L CS )’s updated value.

[0198] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13) In one example of the transmission procedure described, in a downlink of a wireless communication system, the first WTRU is a base station equipment and the second WTRU is a UE.

[0199] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 )In one example of the transmission procedure described, the set of first WTRUs is a plurality of transmission and reception points in a downlink of a multi-TRP wireless communication system.

[0200] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 )In one example of the transmission procedure described, the first WTRU and the second WTRU are UEs in a side link of a wireless communication system.

[0201] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) In one example of the transmission procedure described, in an uplink of a wireless communication system, the first WTRU is a UE and the second WTRU is a base station equipment.

[0202] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 )In one instance of the transmission procedure described, the second set of WTRUs is a plurality of transmit and receive points in the uplink of a multi-TRP wireless communication system.

[0203] Fig.13 An example procedure for receiving a CP-OFDM signal based on phase noise cyclic partitioning is illustrated. In this example, a first WTRU or a set of first WTRUs receiving a CP-OFDM symbol from a second WTRU or a set of second WTRUs may perform one or more of the following actions: at 1301, receive the CP-OFDM symbol; at 1302, perform channel estimation, equalization, and / or common phase error compensation in the frequency domain of the received CP-OFDM; at 1303, obtain / determine a subcarrier group size M and a length L of a frequency domain cyclic prefix via (e.g., signaling indication) CP and / or the length L of the frequency domain cyclic suffix CS At 1304, determine the parameters (e.g., M, L CP and / or L CS) is greater than zero, if so, at 1305, the estimated phase noise ICI component in each subcarrier group is averaged and phase noise ICI compensation is performed; at 1304, if the parameter is not greater than zero, at 1306, phase noise ICI estimation and compensation are performed on the user's allocation; at 1307, the subcarrier is demodulated and the residual phase noise ICI power is compared with a threshold; at 1308, if the residual phase noise ICI power is lower than the threshold, the process can return to the start 1301; at 1308 At 1309, if the residual phase noise ICI power is above a threshold, a phase noise characteristic (e.g., a phase noise spectrum width) is determined based on the residual phase noise ICI power being above a threshold (e.g., 1308); and / or at 1310, a high phase noise indication is transmitted, which includes information about the expected or experienced amount of phase noise in the communication link, such as phase noise capability information and / or phase noise spectrum width; upon completion of 1310, the process may return to any of the previous steps, such as 1301.

[0204] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, channel estimation may be performed by a first WTRU or a set of first WTRUs with the aid of a demodulation reference signal (e.g., DM-RS) inserted in the frequency domain within the allocated bandwidth of the WTRU.

[0205] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one instance of the transmission procedure described, common phase error compensation may be performed by a first WTRU or a set of first WTRUs with the aid of a phase tracking reference signal (e.g., PT-RS) inserted in the frequency domain within the allocated bandwidth of the WTRU.

[0206] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, the subcarrier group size and the length of the frequency domain cyclic prefix and / or cyclic suffix may be obtained by the first WTRU or a set of first WTRUs with the aid of higher layer signaling (e.g., via RRC phase noise configuration information).

[0207] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13) in one example of the transmission procedure described, the subcarrier group size and the length of the frequency domain cyclic prefix and / or cyclic suffix may be obtained from a signaling indication transmitted by a second WTRU or a set of second WTRUs, for example via a downlink shared control or data channel (PDCCH or PDSCH) or by a MAC CE.

[0208] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one instance of the transmission procedure described, the signaling indication may be transmitted by the second WTRU or a set of second WTRUs in a periodic, semi-periodic, on-demand, or event-based manner, where the periodicity is obtained via higher layer signaling or received in a phase noise configuration message (via (e.g., a downlink shared control or data channel (PDCCH or PDSCH) or a MAC CE)).

[0209] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, the subcarrier group size and the length of the frequency-domain cyclic prefix and / or cyclic suffix may be obtained by means of an index into a codebook of a priori defined combinations of the length of the frequency-domain cyclic prefix and cyclic suffix and the subcarrier group size, which combinations must be known to the first WTRU or a set of first WTRUs and the second WTRU or a set of second WTRUs for unambiguous detection.

[0210] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) In one example of the transmission procedure described in the present invention, the subcarrier group size and the length of the frequency-domain cyclic prefix and / or cyclic suffix may be obtained by the first WTRU or a set of first WTRUs through blind detection.

[0211] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described in the present invention, the estimation of the phase noise ICI component may involve obtaining, by a first WTRU or a set of first WTRUs, a set of ICI coefficients in each of one or more subcarrier groups, and further averaging the phase noise ICI component over the subcarrier groups to benefit from frequency diversity.

[0212] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of a transmission procedure described in the accompanying drawings, performing phase noise ICI compensation may be based on applying a Hermitian conjugate of a phase noise ICI spectral response based on a phase noise ICI component averaged over a subcarrier group.

[0213] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) In one example of the transmission procedure described in the present invention, the residual phase noise ICI power may be measured by the first WTRU or a set of first WTRUs based on an average constellation error of subcarrier complex symbols after demodulation.

[0214] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of a transmission procedure described in the present invention, the phase noise spectral width may be measured by a first WTRU or a set of first WTRUs for a received symbol or set of symbols and expressed in units of Hz or the number of subcarriers of the current parameter set.

[0215] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described, the threshold represents a maximum tolerable phase noise ICI power, above which the first WTRU or a set of first WTRUs sends a high phase noise indication to the second WTRU or a set of second WTRUs to request a reduction in phase noise.

[0216] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described in the present invention, the value of the threshold may be obtained by means of high-layer signaling (eg, via RRC phase noise configuration information).

[0217] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one instance of the transmission procedure described in the present invention, the value of the threshold may be transmitted by the second WTRU or a set of second WTRUs in a phase noise configuration message, for example, in a downlink shared control or data channel (PDCCH or PDSCH), or by means of a MAC CE.

[0218] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described in , the high phase noise indication may be reported by the first WTRU in an uplink shared control or data channel (e.g., PUCCH or PUSCH), or by means of a MAC CE.

[0219] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 )In one example of a transmission procedure described in the present invention, the phase noise information may include phase noise capability information or the amount of phase noise experienced in the communication link.

[0220] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of the transmission procedure described in the present invention, the phase noise information may include an indication to the second WTRU or a set of second WTRUs, the indication including a preferred subcarrier partitioning, the indication being achieved by indexing into a codebook of a priori defined combinations of lengths of frequency-domain cyclic prefixes and cyclic suffixes and subcarrier group sizes, which are known to the first WTRU or a set of first WTRUs and the second WTRU or a set of second WTRUs.

[0221] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of a transmit procedure described in the context of FIG. 1 , the phase noise capability may include an indication of an a priori known RF class or oscillator quality class within a set of a priori classes or classes, or an indication of the expected amount of phase noise experienced under typical operating conditions (such as temperature, power, or cell load).

[0222] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of a transmission procedure described herein, the amount of phase noise in the phase noise capability may be expressed as a phase noise spectrum width measured in Hz or number of subcarriers for a given parameter set or set of parameter sets.

[0223] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13) in one example of a transmission procedure described herein, the phase noise amount may be expressed as the number of ICI coefficients that are not negligible in the phase noise spectrum response under current operating conditions.

[0224] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of a transmission procedure described herein, the amount of phase noise may be expressed as the power of the experienced phase noise impairment in watts, milliwatts, dBW, dBm, or any other suitable units.

[0225] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of a transmission procedure described herein, the amount of phase noise may be represented as an indication of a post-detection signal-to-noise ratio measured at a receiving entity after equalization and phase noise compensation.

[0226] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of a transmission procedure described herein, the amount of phase noise may be expressed as a detected residual mean square error at the output of a phase noise compensation algorithm.

[0227] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) in one example of a transmission procedure described in the context of FIG. 1 , the amount of phase noise may be expressed as the error vector magnitude of the constellation as seen at the receiving entity after equalization.

[0228] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) In one example of the transmission procedure described, in a downlink of a wireless communication system, the first WTRU is a UE and the second WTRU is a base station equipment.

[0229] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 )In one instance of the transmission procedure described, the second set of WTRUs is a plurality of transmission and reception points in a downlink of a multi-TRP wireless communication system.

[0230] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 )In one example of the transmission procedure described, the first WTRU and the second WTRU are UEs in a side link of a wireless communication system.

[0231] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 ) In one example of the transmission procedure described, in an uplink of a wireless communication system, the first WTRU is a base station equipment and the second WTRU is a UE.

[0232] In this document (for example, with respect to any figures, descriptions or examples herein, such as Fig.11 , Fig.12 , Fig.13 )In one example of the transmission procedure described, the set of first WTRUs is a plurality of transmission and reception points in the uplink of a multi-TRP wireless communication system.

[0233] Fig.14An example method for determining and indicating high phase noise according to one or more techniques described herein is illustrated. In this example, the method may be implemented by any device disclosed herein (e.g., a network node, a WTRU, a TRP, a base station, etc.). At 1401, a device may receive a configuration message, wherein the configuration message may include a subcarrier group size, a length of a frequency domain cyclic prefix (FD-CP), and / or a length of a frequency domain cyclic suffix (FD-CS). At 1402, the device may process the received symbol based on the configuration information. The processing may include: performing phase noise inter-carrier interference (ICI) compensation of the CP-OFDM symbol based on a communication link for receiving the CP-OFDM symbol, using an average phase noise estimated from one or more subcarrier groups, the average phase noise being based on the subcarrier group size after removing any one or more of the FP-CP or FD-CS. The processing may also include: demodulating the subcarriers of the one or more subcarrier groups, and comparing the residual phase noise ICI power of the demodulated subcarriers with a threshold. At 1403, the device may determine a phase noise characteristic based on the residual phase noise ICI power above the threshold. At 1404, the device may transmit a high phase noise indication including the phase noise characteristic, wherein the phase noise characteristic includes information about the expected amount of phase noise or the measured amount of phase noise in the communication link for receiving the CP-OFDM symbol. In an example that can be combined with other instances and examples, the configuration message is part of a control channel transmission, MAC CE, or RRC signaling. In an example that can be combined with other instances and examples, the configuration message is determined by blind decoding. In an example that can be combined with other instances and examples, the threshold is determined according to RRC signaling. In an example that can be combined with other instances and examples, the high phase noise indication is part of an uplink control channel message, an uplink shared channel message, or a MAC CE. In an example that can be combined with other instances and examples, the phase noise characteristic includes a phase noise spectrum width. In an example that can be combined with other instances and examples, the device is a wireless transmit and receive unit or a base station. As described herein, a sender entity and / or a receiver entity may generally refer to any apparatus described herein, such as a WTRU and / or a base station.

[0234] As described herein, a higher layer may refer to one or more layers in a protocol stack, or a specific sublayer within a protocol stack. A protocol stack may include one or more layers in a WTRU or a network node (e.g., an eNB, a gNB, other functional entities, etc.), each of which may have one or more sublayers. Each layer / sublayer may be responsible for one or more functions. Each layer / sublayer may communicate directly or indirectly with one or more layers in other layers / sublayers. In some cases, the layers may be numbered, such as layer 1, layer 2, and layer 3. For example, layer 3 may include one or more of the following: non-access stratum (NAS), Internet protocol (IP), and / or radio resource control (RRC). For example, layer 2 may include one or more of the following: packet data convergence control (PDCP), radio link control (RLC), and / or medium access control (MAC). For example, layer 3 may include physical (PHY) layer type operations. The larger the number of a layer, the higher the layer is relative to other layers (e.g., layer 3 is higher than layer 1). In some cases, the foregoing examples may be referred to as layers / sublayers themselves, regardless of the layer number, and may be referred to as higher layers as described herein. For example, from highest to lowest, a higher layer may refer to one or more of the following layers / sublayers: a NAS layer, an RRC layer, a PDCP layer, an RLC layer, a MAC layer, and / or a PHY layer. Any reference to a higher layer in conjunction with a process, device, or system herein will refer to a layer higher than the layer of the process, device, or system. In some cases, references to a higher layer herein may refer to a function or operation performed by one or more layers described herein. In some cases, references to a higher layer herein may refer to information transmitted or received by one or more layers described herein. In some cases, references to a higher layer herein may refer to a configuration transmitted and / or received by one or more layers described herein.

[0235] Although features and elements are described above in specific combinations (e.g., embodiments, methods, examples, etc.), it will be understood by those of ordinary skill in the art that each feature or element may be used alone or in any combination with other features and elements. For example, as disclosed herein, for illustrative purposes, there may be a method described in conjunction with the accompanying drawings, and it will be understood by those of ordinary skill in the art that one or more features or elements from this method may be used alone or in combination with one or more features from another method described elsewhere. In addition, any method described herein may be implemented in a device running a computer program, software, and / or firmware that is incorporated in a computer-readable medium for execution by a computer and / or processor operatively connected to a (e.g., wireless or wired) transceiver of the device. Examples of computer-readable media include electronic signals (sent 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 removable disks), magneto-optical media, and optical media (such as CD-ROM disks and digital versatile disks (DVDs)). A processor in association with software may be used to implement a radio frequency transceiver for a WTRU, UE, terminal, base station, RNC, or any host computer.

Claims

1. A method implemented by a device, the method comprising: receiving a configuration message, wherein the configuration message includes a subcarrier group size, a length of a frequency domain cyclic prefix (FD-CP), and a length of a frequency domain cyclic suffix (FD-CS); performing phase noise inter-carrier interference (ICI) compensation of the CP-OFDM symbol based on a communication link for receiving the CP-OFDM symbol using an average phase noise estimated from one or more subcarrier groups, the average phase noise being based on the subcarrier group size after removing any one or more of the FP-CP or the FD-CS; demodulating subcarriers of the one or more subcarrier groups, and comparing residual phase noise ICI power of the demodulated subcarriers with a threshold; determining a phase noise characteristic based on the residual phase noise ICI power being above the threshold; as well as A high phase noise indication is transmitted including the phase noise characteristic, wherein the phase noise characteristic includes information regarding an expected amount of phase noise or a measured amount of phase noise in the communication link for receiving the CP-OFDM symbol.

2. The method of claim 1, wherein the configuration message is part of a control channel transmission, MAC CE or RRC signaling.

3. The method according to one or more of claims 1 to 2, wherein the configuration message is determined by blind decoding.

4. The method according to one or more of claims 1 to 3, wherein the threshold is determined according to RRC signaling.

5. The method according to one or more of claims 1 to 4, wherein the high phase noise indication is part of an uplink control channel message, an uplink shared channel message or a MAC CE.

6. The method according to one or more of claims 1 to 5, wherein the phase noise characteristic comprises a phase noise spectral width.

7. The method according to one or more of claims 1 to 6, wherein the device is a wireless transceiver unit or a base station.

8. A device, comprising: means for receiving a configuration message, wherein the configuration message comprises a subcarrier group size, a length of a frequency domain cyclic prefix (FD-CP), and a length of a frequency domain cyclic suffix (FD-CS); means for performing phase noise inter-carrier interference (ICI) compensation of the CP-OFDM symbols based on a communication link for receiving the CP-OFDM symbols using an average phase noise estimated from one or more subcarrier groups, the average phase noise being based on the subcarrier group size after removing any one or more of FP-CP or FD-CS; means for demodulating subcarriers of the one or more subcarrier groups, and comparing residual phase noise ICI power of the demodulated subcarriers with a threshold; means for determining a phase noise characteristic based on the residual phase noise ICI power being above the threshold; and Means for transmitting a high phase noise indication comprising the phase noise characteristic, wherein the phase noise characteristic comprises information regarding an expected amount of phase noise or a measured amount of phase noise in the communication link for receiving the CP-OFDM symbol.

9. The apparatus of claim 8, wherein the configuration message is part of a control channel transmission, MAC CE or RRC signaling.

10. The device according to one or more of claims 8 to 9, wherein the configuration message is determined by blind decoding.

11. The apparatus according to one or more of claims 8 to 10, wherein the threshold is determined according to RRC signaling.

12. The apparatus according to one or more of claims 8 to 11, wherein the high phase noise indication is part of an uplink control channel message, an uplink shared channel message or a MAC CE.

13. The apparatus according to one or more of claims 8 to 12, wherein the phase noise characteristic comprises a phase noise spectral width.

14. The device according to one or more of claims 8 to 13, wherein the device is a wireless transceiver unit or a base station.

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