Methods and apparatuses for constellation shaping for single-carrier waveform with selection of an MCS table

Abstract

A wireless transmit / receive (WTRU) unit may send an indication of a set of modulation schemes supported by the WTRU. The WTRU may receive configuration information indicating at least one modulation and coding scheme (MCS) table, wherein the at least one MCS table indicates a plurality of modulation schemes and respective parameters associated with each modulation scheme of the plurality of the modulation schemes, and wherein each modulation scheme of the plurality of the modulation schemes is associated with a different constellation shape. The WTRU may receive downlink control information (DCI) that comprises an indication of a configured modulation scheme indicated by the at least one MCS table and respective parameters associated with the configured modulation scheme. The WTRU may receive a downlink transmission based on the configured modulation scheme and the respective parameters associated with the configured modulation scheme. The WTRU may send an indication of a preferred modulation scheme.

Description

METHODS AND APPARATUSES FOR CONSTELLATION SHAPING FOR SINGLE-CARRIER WAVEFORM WITH SELECTIONOF AN MCS TABLECROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of United States Provisional Application No. 63 / 549,085 filed on February 2, 2024, the entire contents of which are incorporated herein by reference.BACKGROUND

[0002] The development of International Mobile Telecommunications (IMT) for 2030 and beyond is expected to enable new use cases and applications with high data rate and low latency, which will benefit from large contiguous bandwidths potentially up to tens of GHz. This suggests the need to consider spectrum in higher frequency (HF) ranges above 92 GHz as a complement to the use of lower frequency band.

[0003] In some current 3GPP implementations, a network system may only provide a single modulation scheme: rectangular QAM (R-QAM) While operating in higher frequency range, the R-QAM has been identified to be not robust with severe radio frequency (RF) impairment conditions like high phase noise (PN) and lower power amplifier (PA) efficiency. PA limitations lead to a choice of modulation schemes (MS) and orders with small envelope variation (e.g., peak to power ratio (PAPR)). PN in the transmitter and the receiver requires modulation schemes that are intrinsically resilient to PN. R-QAM is not robust with higher PN and higher PAPR when modulation order goes higher. This would impact higher modulation order use cases when operating in HF range, hampering overall system performance.

[0004] Single carrier (SC) waveform is a preferred waveform in HF because they have lower PAPR and are more robust to PN than multicarrier waveforms (e.g., cyclic prefix orthogonal frequency division multiplexing CP-OFDM). However, existing new radio (NR) modulation scheme (e.g., R-QAM) is not robust to PN when the modulation order goes higher even for SC waveforms. Compensation for this problem requires allocation of higher phase tracking reference signal (PT-RS) density and higher sampling rate (e.g., subcarrier spacing) to alleviate the impact of PN. When PT-RS density is higher, it leads to lower spectrum efficiency. In addition, higher sampling rate may hamper achieving higher data rate due to analog to digital converter (ADC) resolution issues thereby increasing power assumption while operating at HF. Furthermore, R-QAM scheme also exhibits higher PAPR which underutilize the PA operation especially in HF range. In short, existing R-QAM in general is robust with additive white gaussian noise (AWGN) but it has been identified to be not robust with severe RF impairment conditions. Therefore, other modulation schemes need be considered to achieve the optimal performance for HF and sub-THz systems.

[0005] In recent research, constellation shaping (CS) has been shown to reduce PAPR while also being robust to PN. This could be especially beneficial for single carrier waveform operations in HF and sub-THz systems. Therefore, methods and techniques need to be explored to leverage CS operation in wireless communications (e.g., in HF systems).SUMMARY

[0006] Support for modulation schemes using constellation shaping (e.g., M-ary amplitude and phaseshift keying (APSK) (M-APSK), etc.) for overcoming RF impairments and enhance performance in high- frequency and sub-THz systems for single carrier waveforms (e.g., single carrier frequency domain equalizer (SC-FDE)). A WTRU reports (e.g., a set of) support modulation schemes with the associated parameters (e.g., modulation order) to the network and receives the configuration associated to modulation schemes based on reported WTRU capability. The network may dynamically signal the appropriate modulation scheme to the WTRU via the indication of modulation and coding scheme.

[0007] The WTRU reports a supported set of modulation schemes to the network. The WTRU receives a configuration from the network with a set of MCS tables where each table contains modulation schemes and associated parameters like PT-RS pattern, constellation parameters, association of modulation scheme and corresponding config to modulation order, range of MCS indices, etc. Some of MCS tables are reconfigurable with configurable lists. MAC-CE can be used for the indication of switching MCS tables to reduce using RNTI and save WTRU complexity. The WTRU receives a DCI, based on an RNTI that schedules at least one of a PDSCH or a PUSCH, and comprising of at least an MCS index indicating the modulation scheme, associated constellation parameters, etc. for the PDSCH reception / PUSCH transmission. The WTRU can indicate the preferred modulation scheme (e.g., X modulation scheme for DL and UL). For DL, the report CQI may be based on the preferred modulation scheme and report the preferred modulation scheme (MS) and CQI to network, i.e., MS + CQI . The WTRU can measure PN RMS / variance based on a particular training sequence (e.g., a BPSK or QPSK sequence) and report the quantized PN RMS / variance back to NW for assistance of NW determining the preferred modulation scheme. The WTRU receives a modulation scheme, PT-RS pattern, constellation parameters, etc., based on the determined MCS table and the indicated MCS index.

[0008] A wireless transmit / receive unit (WTRU) that includes a processor, may send an indication of a set of modulation schemes supported by the WTRU. The WTRU may receive configuration information indicating at least one modulation and coding scheme (MCS) table, wherein the at least one MCS table indicates a plurality of modulation schemes and respective parameters associated with each modulation scheme of the plurality of the modulation schemes, and wherein each modulation scheme of the plurality of the modulation schemes is associated with a different constellation shape. The WTRU may receivedownlink control information (DCI) that comprises an indication of a configured modulation scheme indicated by the at least one MCS table and respective parameters associated with the configured modulation scheme. The WTRU may receive a downlink transmission based on the configured modulation scheme and the respective parameters associated with the configured modulation scheme. The WTRU may send an indication of a preferred modulation scheme for downlink transmissions or uplink transmissions based on one or more measurements.

[0009] In an example, the constellation shape may comprise rectangular quadrature amplitude modulation (QAM), differential M-ary amplitude and phase-shift keying (APSK) (M-APSK) modulation, or X- QAM. The at least one MCS table may comprise a first MCS table and a second MCS table, wherein the first MCS table may indicate a first modulation scheme and a first parameters associated with the first modulation scheme, and wherein the second MCS table may indicate a second modulation scheme and a second parameters associated with the second modulation scheme. The parameters associated with each modulation scheme may comprise a phase tracking reference signal (PT-RS) pattern, constellation parameters, an association of a modulation scheme and corresponding configuration with a modulation order, or a range of MCS indices. The WTRU may be configured to calculate channel quality indicator (CQI) based on the preferred modulation scheme; and may send an indication of the CQI. The constellation shaping technique may comprise probability constellation shaping (PCS) or geometric constellation shaping (GCS). The configuration information may comprise at least an MCS index indicating a modulation scheme and associated constellation parameters for a physical downlink shared channel (PDSCH) reception or a physical uplink shared channel (PUSCH) transmission. The configuration information may comprise an radio network temporary identifier (RNTI) that schedules one or more of PDSCH or PUSCH transmission. An MSC table of the set of MCS tables may be reconfigurable with a configurable list. The WTRU may be configured to measure phase noise root mean squared variance (PN RMS / variance) based on a particular training sequence and report the PN RMS / variance to anetwork entity for assistance of the network entity to determine a preferred modulation scheme.

[0010] According to one example aspect, the disclosure relates to a method implemented in a WTRU, the method comprising sending an indication of a set of modulation schemes supported by the WTRU. The method comprises receiving configuration information indicating at least one modulation and coding scheme (MCS) table, wherein the at least one MCS table indicates a plurality of modulation schemes and respective parameters associated with each modulation scheme of the plurality of the modulation schemes, and wherein each modulation scheme of the plurality of the modulation schemes is associated with a different constellation shape. The method comprises receiving downlink control information (DCI) that comprises an indication of a configured modulation scheme indicated by the at least one MCS table and respective parameters associated with the configured modulation scheme. The method comprisesreceiving a downlink transmission based on the configured modulation scheme and the respective parameters associated with the configured modulation scheme. The method comprises sending an indication of a preferred modulation scheme for downlink transmissions or uplink transmissions based on one or more measurements.

[0011] In an example, the constellation shape may comprise rectangular quadrature amplitude modulation (QAM), differential M-ary amplitude and phase-shift keying (APSK) (M-APSK) modulation, or X- QAM. The at least one MCS table may comprise a first MCS table and a second MCS table, wherein the first MCS table may indicate a first modulation scheme and a first parameters associated with the first modulation scheme, and wherein the second MCS table may indicate a second modulation scheme and a second parameters associated with the second modulation scheme. The parameters associated with each modulation scheme may comprise a phase tracking reference signal (PT-RS) pattern, constellation parameters, an association of a modulation scheme and corresponding configuration with a modulation order, or a range of MCS indices. In an example, the method further comprising, calculating channel quality indicator (CQI) based on the preferred modulation scheme; and sending an indication of the CQI. The constellation shaping technique may comprise probability constellation shaping (PCS) or geometric constellation shaping (GCS). The configuration information may comprise at least an MCS index indicating a modulation scheme and associated constellation parameters for a physical downlink shared channel (PDSCH) reception or a physical uplink shared channel (PUSCH) transmission The configuration information comprises a radio network temporary identifier (RNTI) that schedules one or more of PDSCH or PUSCH transmission. An MSC table of the set of MCS tables may be reconfigurable with a configurable list. In an example, the method further comprising measuring phase noise root mean squared variance (PN RMS / variance) based on a particular training sequence and reporting the PN RMS / variance to a network entity for assistance of the network entity to determine a preferred modulation scheme.BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG. 1A is a system diagram illustrating an example communications system in which one or more disclosed embodiments may be implemented;

[0013] FIG. 1 B is a system diagram illustrating an example wireless transmit / receive unit (WTRU) that may be used within the communications system illustrated in FIG. 1A according to an embodiment;

[0014] FIG. 1C is a system diagram illustrating an example radio access network (RAN) and an example core network (CN) that may be used within the communications system illustrated in FIG. 1A according to an embodiment;

[0015] FIG. 1 D is a system diagram illustrating a further example RAN and a further example CN that may be used within the communications system illustrated in FIG. 1A according to an embodiment;

[0016] FIG. 2 includes three diagrams each illustrating an example of an amplitude and phase-shift keying (APSK) modulation scheme and peak to power ratio (PAPR) performance, according to one or more embodiments;

[0017] FIG. 3 includes two diagrams illustrating an example of an APSK modulation scheme and its bit error rate (BER) performance when phase noise (PN) variance is equal to 0.05, according to one or more embodiments;

[0018] FIG. 4 is a diagram illustrating an example of a concentric ring, constellation points and radius of the concentric ring for M-ary APSK (M-APSK) modulation, according to one or more embodiments;

[0019] FIG. 5 includes three diagrams each illustrating an example of a low-PAPR modulation scheme and constellation points for single-carrier (SC) waveform (e.g., SC-FDE), according to one or more embodiments;

[0020] FIG. 6 includes two diagrams each illustrating an example of a PN robust modulation scheme for SC waveform (e.g. single carrier frequency domain equalizer (SC-FDE)), according to one or more embodiments;

[0021] FIG. 7A is a system diagram illustrating an example of an SC-FDE transmitter with probability constellation shaping (PCS), according to one or more embodiments;

[0022] FIG. 7B is a system diagram illustrating an example of an SC-FDE receiver with PCS, according to one or more embodiments, according to one or more embodiments;

[0023] FIG. 8 is a block diagram illustrating an example of a PN robust modulation scheme, according to one or more embodiments;

[0024] FIG. 9 is a block diagram illustrating an example of phase tracking reference signal (PT-RS) pattern design for SC-FDE, according to one or more embodiments;

[0025] FIG. 10 is a block diagram illustrating an example of (a) an SC-FDE transmitter and (b) an SC- FDE block, according to one or more embodiments;

[0026] FIG. 11 is a block diagram illustrating an example of a training sequence design for SC-FDE to estimate phase noise root mean squared (PN RMS), according to one or more embodiments;

[0027] FIG. 12 is a flow chart illustrating an example of a WTRU procedure to determine the number of data symbols and information bits in SC-FDE, according to one or more embodiments;

[0028] FIG. 13 is a flow chart illustrating an example of a WTRU procedure to report a preferred downlink (DL) modulation scheme with channel quality indicator (CQI) report, according to one or more embodiments;

[0029] FIG. 14A is a diagram illustrating an example of a WTRU procedure to report a preferred modulation scheme wherein a WTRU triggers a SR and reports the preferred modulation scheme, according to one or more embodiments; and

[0030] FIG. 14B is a diagram illustrating an example of a WTRU procedure to report a preferred modulation scheme wherein a WTRU reports the preferred modulation scheme at the first RUSCH transmission, according to one or more embodiments.DETAILED DESCRIPTION

[0031] FIG. 1A is a system diagram illustrating an example communications system 100 in which one or more disclosed embodiments may be implemented. The communications system 100 may be a multiple access system that provides content, such as voice, data, video, messaging, broadcast, etc., to multiple wireless users. The communications system 100 may enable multiple wireless users to access such content through the sharing of system resources, including wireless bandwidth. For example, the communications systems 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 (ZT) unique-word (UW) discreet Fourier transform (DFT) spread OFDM (ZT UW DTS-s OFDM), unique word OFDM (UW-OFDM), resource block-filtered OFDM, filter bank multicarrier (FBMC), and the like.

[0032] As shown in FIG. 1A, the communications system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, a radio access network (RAN) 104 / 113, a core network (ON) 106 / 115, a public switched telephone network (PSTN) 108, the Internet 110, and other networks 112, though it will be appreciated 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. By way of example, the WTRUs 102a, 102b, 102c, 102d, any of which may be referred to as a "station" and / or a "STA", may be configured to transmit and / or receive wireless signals and may include (or be) a user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a subscription-based unit, a pager, a cellular telephone, a personal digital assistant (PDA), a smartphone, a laptop, a netbook, a personal computer, a wireless sensor, a hotspot or Mi-Fl device, an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, a medical device and applications (e.g., remote surgery), an industrial device and applications (e.g., a robot and / or other wireless devices operating in an industrial and / or an automated processing chain contexts), a consumer electronics device, a device operating on commercial and / or industrial wireless networks, and the like. Any of the WTRUs 102a, 102b, 102c and 102d may be interchangeably referred to as a UE.

[0033] The communications systems 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, e.g., to facilitate access to one or morecommunication networks, such as the CN 106 / 115, the Internet 110, and / or the networks 112. By way of example, the base stations 114a, 114b may be any of a base transceiver station (BTS), a Node-B (NB), an eNode-B (eNB), a Home Node-B (HNB), a Home eNode-B (HeNB), a gNode-B (g NB), a NR Node-B (NR NB), 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.

[0034] The base station 114a may be part of the RAN 104 / 113, 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), relay nodes, etc. The base station 114a and / or the base station 114b may be configured to transmit and / or receive wireless signals on one or more carrier frequencies, which may be referred to as a cell (not shown). These frequencies may be in licensed spectrum, unlicensed spectrum, or a combination of licensed and unlicensed spectrum. A cell may provide coverage for a wireless service to a specific geographical area that may be relatively fixed or that may change over time. The cell may further be divided into cell sectors. For example, the cell associated with the base station 114a may be divided into three sectors. Thus, in an embodiment, the base station 114a may include three transceivers, i.e., one for each sector of the cell. In an embodiment, the base station 114a may employ multiple-input multiple output (MIMO) technology and may utilize multiple transceivers for each or any sector of the cell. For example, beamforming may be used to transmit and / or receive signals in desired spatial directions.

[0035] 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).

[0036] More specifically, as noted above, the communications 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, and the like. For example, the base station 114a in the RAN 104 / 113 and the WTRUs 102a, 102b, 102c may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may establish the air interface 116 using wideband CDMA (WCDMA). WCDMA may include communication protocols such as High-Speed Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA may include High-Speed Downlink Packet Access (HSDPA) and / or High-Speed Uplink Packet Access (HSUPA).

[0037] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface 116 using Long Term Evolution (LTE) and / or LTE-Advanced (LTE-A) and / or LTE-Advanced Pro (LTE-A Pro).

[0038] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as NR Radio Access, which may establish the air interface 116 using New Radio (NR).

[0039] In an 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 implement LTE radio access and NR radio access together, for instance using dual connectivity (DC) principles. Thus, the air interface utilized by WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and / or transmissions sent to / from multiple types of base stations (e.g . , an eNB and a gNB).

[0040] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement radio technologies such as IEEE 802.11 (i.e., Wireless Fidelity (Wi-Fi), 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), and the like.

[0041] The base station 114b in FIG. 1A may be a wireless router, Home Node-B, Home eNode-B, or access point, for example, and may utilize any suitable RAT for facilitating wireless connectivity in a localized area, such as a place of business, a home, a vehicle, a campus, an industrial facility, an air corridor (e.g., for use by drones), a roadway, and the like. In an 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 an 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 an 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 any of a small cell, picocell or femtocell. As shown in FIG. 1A, the base station 114b may have a direct connection to the Internet 110. Thus, the base station 114b may not be required to access the Internet 110 via the CN 106 / 115

[0042] The RAN 104 / 113 may be in communication with the CN 106 / 115, 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 varying quality of service (QoS) requirements, such as differing throughput requirements, latency requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, and the like. The CN 106 / 115 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 userauthentication. Although not shown in FIG. 1 A, it will be appreciated that the RAN 104 / 113 and / or the CN 106 / 115 may be in direct or indirect communication with other RANs that employ the same RAT as the RAN 104 / 113 or a different RAT. For example, in addition to being connected to the RAN 104 / 113, which may be utilizing an NR radio technology, the CN 106 / 115 may also be in communication with another RAN (not shown) employing any of a GSM, UMTS, CDMA 2000, WiMAX, E-UTRA, or Wi-Fi radio technology.

[0043] The CN 106 / 115 may also serve 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 circuit-switched telephone networks that provide 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), user datagram protocol (UDP) and / or the internet protocol (IP) in the TCP / IP internet protocol suite. The networks 112 may include wired and / or wireless communications 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 / 114 or a different RAT.

[0044] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communications 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 over different wireless links). For example, the WTRU 102c shown in FIG 1A 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.

[0045] FIG. 1 B is a system diagram illustrating an example WTRU 102. As shown in FIG. 1 B, the WTRU 102 may include 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 elements / peripherals 138, among others. It will be appreciated that the WTRU 102 may include any subcombination of the foregoing elements while remaining consistent with an embodiment.

[0046] The processor 118 may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) circuits, any other type of integrated circuit (IC), a state machine, and the like. The processor 118 may perform signal coding, data processing, power control, input / output processing, and / or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit / receive element 122. While FIG. 1 B depicts the processor 118 and thetransceiver 120 as separate components, it will be appreciated that the processor 118 and the transceiver 120 may be integrated together, e.g., in an electronic package or chip.

[0047] The transmit / receive element 122 may be configured to transmit signals to, or receive signals from, a base station (e.g., the base station 114a) over the air interface 116. For example, in an embodiment, the transmit / receive element 122 may be an antenna configured to transmit and / or receive RF signals. In an embodiment, the transmit / receive element 122 may be an emitter / detector configured to transmit and / or receive IR, UV, or visible light signals, for example. In an embodiment, the transmit / receive element 122 may be configured to transmit and / or receive both RF and light signals. It will be appreciated that the transmit / receive element 122 may be configured to transmit and / or receive any combination of wireless signals.

[0048] Although the transmit / receive element 122 is depicted in FIG. 1B as a single element, the WTRU 102 may include any number of transmit / receive elements 122. For example, the WTRU 102 may employ MIMO technology. Thus, in an 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.

[0049] The transceiver 120 may be configured to modulate the signals that are to be transmitted by the transmit / receive element 122 and to demodulate the signals that are received by the transmit / receive element 122 As noted above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers for enabling the WTRU 102 to communicate via multiple RATs, such as NR and IEEE 802.11 , for example.

[0050] The processor 118 of the WTRU 102 may be coupled to, and may receive user input data from, the speaker / microphone 124, the keypad 126, and / or the display / touchpad 128 (e.g., a liquid crystal display (LCD) display unit or 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 the non-removable memory 130 and / or the removable memory 132. The non-removable memory 130 may include random-access memory (RAM), read-only memory (ROM), a hard disk, or any other type of memory storage device. 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, memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0051] The processor 118 may receive power from the power source 134, and may be configured to distribute and / or control the power to the 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 oneor 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, and the like.

[0052] 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 over the air interface 116 from a base station (e.g., base stations 114a, 114b) and / or determine its location based on the timing of the signals being received from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information by way of any suitable locationdetermination method while remaining consistent with an embodiment.

[0053] The processor 118 may further be coupled to other elements / peripherals 138, which may include one or more software and / or hardware modules / units that provide additional features, functionality and / or wired or wireless connectivity. For example, the elements / peripherals 138 may include an accelerometer, an e-compass, a satellite transceiver, a digital camera (e.g., for photographs and / or video), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands free headset, a Bluetooth® module, a frequency modulated (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, and the like. The elements / peripherals 138 may include one or more sensors, the sensors may be one or more of a gyroscope, an accelerometer, a hall effect sensor, a magnetometer, an orientation sensor, a proximity sensor, a temperature sensor, a time sensor; a geolocation sensor; an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, and / or a humidity sensor.

[0054] 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 particular subframes for both the uplink (e.g., for transmission) and downlink (e.g., for reception) may be concurrent and / or simultaneous. The full duplex radio may include an interference management unit to reduce and or substantially eliminate self-interference via either hardware (e.g., a choke) or signal processing via a processor (e.g., a separate processor (not shown) or via 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 particular subframes for either the uplink (e.g., for transmission) or the downlink (e.g., for reception)).

[0055] FIG. 10 is a system diagram illustrating the RAN 104 and the CN 106 according to an embodiment. As noted above, the RAN 104 may employ an E-UTRA radio technology to communicate with the WTRUs 102a, 102b, and 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0056] The RAN 104 may include eNode-Bs 160a, 160b, 160c, though it will be appreciated that the RAN 104 may include any number of eNode-Bs while remaining consistent with an embodiment. The eNode-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 an embodiment, the eNode-Bs 160a, 160b, 160c may implement MIMO technology. Thus, the eNode-B 160a, for example, may use multiple antennas to transmit wireless signals to, and receive wireless signals from, the WTRU 102a.

[0057] Each of the eNode-Bs 160a, 160b, and 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 uplink (UL) and / or downlink (DL), and the like. As shown in FIG. 1 C, the eNode-Bs 160a, 160b, 160c may communicate with one another over an X2 interface.

[0058] The CN 106 shown in FIG. 1C may include a mobility management entity (MME) 162, a serving gateway (SGW) 164, and a packet data network (PDN) gateway (PGW) 166. While each of the foregoing elements are depicted as part of the CN 106, it will be appreciated that any one of these elements may be owned and / or operated by an entity other than the CN operator.

[0059] The MME 162 may be connected to each of the eNode-Bs 160a, 160b, and 160c 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, and the like. 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.

[0060] The SGW 164 may be connected to each of the eNode-Bs 160a, 160b, 160c in the RAN 104 via the 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 user planes during inter- eNode-B handovers, triggering paging when DL data is available for the WTRUs 102a, 102b, 102c, managing and storing contexts of the WTRUs 102a, 102b, 102c, and the like.

[0061] 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.

[0062] 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 communicate with, an IP gateway (e.g., an IP multimedia subsystem (IMS) server) that serves as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to the other networks 112,which may include other wired and / or wireless networks that are owned and / or operated by other service providers.

[0063] Although the WTRU is described in FIGs. 1 A-1 D as a wireless terminal, it is contemplated that in certain representative embodiments that such a terminal may use (e.g. , temporarily or permanently) wired communication interfaces with the communication network.

[0064] In representative embodiments, the other network 112 may be a WLAN.

[0065] A WLAN in infrastructure basic service set (BSS) mode may have an access point (AP) for the BSS and one or more stations (STAs) associated with the AP. The AP may have an access or an interface to a distribution system (DS) or another type of wired / wireless network that carries traffic into and / or out of the BSS. Traffic to STAs that originates from outside the BSS may arrive through the AP and may be delivered to the STAs. Traffic originating from STAs to destinations outside the BSS may be sent to the AP to be delivered to respective destinations. Traffic between STAs within the BSS may be sent through the AP, for example, where the source STA may send traffic to the AP and the AP may deliver the traffic to the destination STA. The traffic between STAs within a BSS may be considered and / or referred to as peer-to- peer traffic. The peer-to-peer traffic may be sent between (e.g., directly between) the source and destination STAs with a direct link setup (DLS). In certain representative embodiments, the DLS may use an 802.11e DLS or an 802.11z tunneled DLS (TDLS). A WLAN using an Independent BSS (IBSS) mode may not have an AP, and the STAs (e g., all of the STAs) within or using the IBSS may communicate directly with each other. The IBSS mode of communication may sometimes be referred to herein as an "ad- hoc” mode of communication.

[0066] When using the 802.11 ac infrastructure mode of operation or a similar mode of operations, the AP may transmit a beacon on a fixed channel, such as a primary channel. The primary channel may be a fixed width (e.g., 20 MHz wide bandwidth) or a dynamically set width via signaling. The primary channel may be the operating channel of the BSS and may be used by the STAs to establish a connection with the AP. In certain representative embodiments, Carrier sense multiple access with collision avoidance (CSMA / CA) may be implemented, for example in in 802.11 systems. For CSMA / CA, the STAs (e.g., every STA), including the AP, may sense the primary channel. If the primary channel is sensed / 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.

[0067] High throughput (HT) STAs may use a 40 MHz wide channel for communication, for example, via a combination of the primary 20 MHz channel with an adjacent or nonadjacent 20 MHz channel to form a 40 MHz wide channel.

[0068] Very high throughput (VHT) STAs may support 20 MHz, 40 MHz, 80 MHz, and / or 160 MHz wide channels. The 40 MHz, and / or 80 MHz, channels may be formed by combining contiguous 20 MHzchannels. A 160 MHz channel may be formed by combining 8 contiguous 20 MHz channels, or by combining two non-contiguous 80 MHz channels, which may be referred to as an 80+80 configuration. For the 80+80 configuration, the data, after channel encoding, may be passed through a segment parser that may divide the data into two streams. Inverse fast fourier transform (IFFT) processing, and time domain processing, may be done on each stream separately. The streams may be mapped on to the two 80 MHz channels, and the data may be transmitted by a transmitting STA. At the receiver of the receiving STA, the above-described operation for the 80+80 configuration may be reversed, and the combined data may be sent to a medium access control (MAC) layer, entity, etc.

[0069] Sub 1 GHz modes of operation are supported by 802.11af and 802.11 ah. The channel operating bandwidths, and carriers, are reduced in 802.11 af and 802.11 ah relative to those used in 802.11n, and 802.11ac. 802.11 af supports 5 MHz, 10 MHz and 20 MHz bandwidths in the TV white space (TVWS) spectrum, and 802.11 ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using non-TVWS spectrum. According to a representative embodiment, 802.11 ah may support meter type control / machine- type communications (MTC), such as MTC devices in a macro coverage area. MTC devices may have certain capabilities, for example, limited capabilities including support for (e.g., only support for) certain and / or limited bandwidths. The MTC devices may include a battery with a battery life above a threshold (e.g., to maintain a very long battery life).

[0070] WLAN systems, which may support multiple channels, and channel bandwidths, such as 802.11 n, 802.11 ac, 802.11 af, and 802.11 ah, include a channel which may be designated as the primary channel. The primary channel may have a bandwidth equal to the largest common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel may be set and / or limited by a STA, from among all STAs in operating in a BSS, which supports the smallest bandwidth operating mode. In the example of 802.11 ah, the primary channel may be 1 MHz wide for STAs (e.g., MTC type devices) that support (e.g., only support) a 1 MHz mode, even if the AP, and other STAs in the BSS support 2 MHz, 4 MHz, 8 MHz, 16 MHz, and / or other channel bandwidth operating modes. Carrier sensing and / or network allocation vector (NAV) settings may depend on the status of the primary channel. If the primary channel is busy, for example, due to a STA (which supports only a 1 MHz operating mode), transmitting to the AP, the entire available frequency bands may be considered busy even though a majority of the frequency bands remains idle and may be available.

[0071] In the United States, the available frequency bands, which may be used by 802.11 ah, are from 902 MHz to 928 MHz. In Korea, the available frequency bands are from 917.5 MHz to 923.5 MHz. In Japan, the available frequency bands are from 916.5 MHz to 927.5 MHz. The total bandwidth available for 802.11 ah is 6 MHz to 26 MHz depending on the country code.

[0072] FIG. 1 D is a system diagram illustrating the RAN 113 and the CN 115 according to an embodiment. As noted above, the RAN 113 may employ an NR radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 113 may also be in communication with the CN 115.

[0073] The RAN 113 may include gNBs 180a, 180b, 180c, though it will be appreciated that the RAN 113 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 an embodiment, the gNBs 180a, 180b, 180c may implement MIMO technology. For example, gNBs 180a, 180b may utilize beamforming to transmit signals to and / or receive signals from the WTRUs 102a, 102b, 102c. Thus, the gNB 180a, for example, may use multiple antennas to transmit wireless signals to, and / or receive wireless signals from, the WTRU 102a. In an 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 unlicensed spectrum while the remaining component carriers may be on licensed spectrum. In an embodiment, the gNBs 180a, 180b, 180c may implement Coordinated Multi-Point (CoMP) technology. For example, WTRU 102a may receive coordinated transmissions from gNB 180a and gNB 180b (and / or gNB 180c).

[0074] The WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using transmissions associated with a scalable numerology. For example, OFDM symbol spacing and / or OFDM subcarrier spacing may vary for different transmissions, different cells, and / or different portions of the wireless transmission spectrum. The WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using subframe or transmission time intervals (TTIs) of various or scalable lengths (e.g., including a varying number of OFDM symbols and / or lasting varying lengths of absolute time).

[0075] 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 the standalone configuration, WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c without also accessing other RANs (e.g., such as eNode-Bs 160a, 160b, 160c). In the standalone configuration, WTRUs 102a, 102b, 102c may utilize one or more of gNBs 180a, 180b, 180c as a mobility anchor point. In the standalone configuration, WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using signals in an unlicensed band. In a non-standalone configuration WTRUs 102a, 102b, 102c may communicate with / connect to gNBs 180a, 180b, 180c while also communicating with / connecting to another RAN such as eNode-Bs 160a, 160b, 160c. For example, WTRUs 102a, 102b, 102c may implement DC principles to communicate with one or more gNBs 180a, 180b, 180c and one or more eNode-Bs 160a, 160b, 160c substantially simultaneously. In the non-standalone configuration, eNode-Bs 160a, 160b, 160c may serveas a mobility anchor for WTRUs 102a, 102b, 102c and gNBs 180a, 180b, 180c may provide additional coverage and / or throughput for servicing WTRUs 102a, 102b, 102c.

[0076] Each of the gNBs 180a, 180b, 180c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the UL and / or DL, support of network slicing, dual connectivity, interworking between NR and E-UTRA, routing of user plane data towards user plane functions (UPFs) 184a, 184b, routing of control plane information towards access and mobility management functions (AMFs) 182a, 182b, and the like. As shown in FIG. 1D, the gNBs 180a, 180b, 180c may communicate with one another over an Xn interface.

[0077] The CN 115 shown in FIG 1 D may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one session management function (SMF) 183a, 183b, and at least one Data Network (DN) 185a, 185b. While each of the foregoing elements are depicted as part of the CN 115, it will be appreciated that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0078] The AMF 182a, 182b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via an N2 interface and may serve as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, support for network slicing (e.g., handling of different protocol data unit (PDU) sessions with different requirements), selecting a particular SMF 183a, 183b, management of the registration area, termination of NAS signaling, mobility management, and the like. Network slicing may be used by the AMF 182a, 182b, e.g., to customize CN support for WTRUs 102a, 102b, 102c based on the types of services being utilized WTRUs 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, and / or the like. The AMF 162 may provide a control plane function for switching between the RAN 113 and other RANs (not shown) that employ other radio technologies, such as LTE, LTE-A, LTE-A Pro, and / or non-3GPP access technologies such as Wi-Fi.

[0079] The SMF 183a, 183b may be connected to an AMF 182a, 182b in the CN 115 via an N11 interface. The SMF 183a, 183b may also be connected to a UPF 184a, 184b in the CN 115 via an N4 interface. The SMF 183a, 183b may select and control the UPF 184a, 184b and configure the routing of traffic through the UPF 184a, 184b. The SMF 183a, 183b may perform other functions, such as managing and allocating UE IP address, managing PDU sessions, controlling policy enforcement and QoS, providing downlink data notifications, and the like. A PDU session type may be IP-based, non-IP based, Ethernetbased, and the like.

[0080] The UPF 184a, 184b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via an N3 interface, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, e.g., to facilitate communications between the WTRUs 102a, 102b,102c and IP-enabled devices. The UPF 184, 184b may perform other functions, such as routing and forwarding packets, enforcing user plane policies, supporting multi-homed PDU sessions, handling user plane QoS, buffering downlink packets, providing mobility anchoring, and the like.

[0081] The CN 115 may facilitate communications with other networks. For example, the CN 115 may include, or may communicate with, an IP gateway (e.g., an IP multimedia subsystem (IMS) server) that serves as an interface between the CN 115 and the PSTN 108. In addition, the CN 115 may provide the WTRUs 102a, 102b, 102c with access to the other networks 112, which may include other wired and / or wireless networks that are owned and / or operated by other service providers. In an embodiment, the WTRUs 102a, 102b, 102c may be connected to a local Data Network (DN) 185a, 185b through the UPF 184a, 184b via the N3 interface to the UPF 184a, 184b and an N6 interface between the UPF 184a, 184b and the DN 185a, 185b.

[0082] In view of FIGs. 1A-1 D, and the corresponding description of FIGs. 1A-1 D, one or more, or all, of the functions described herein with regard to any of: WTRUs 102a-d, base stations 114a-b, eNode-Bs 160a-c, MME 162, SGW 164, PGW 166, gNBs 180a-c, AMFs 182a-b, UPFs 184a-b, SMFs 183a-b, DNs 185a-b, and / or any other element(s) / device(s) described herein, may be performed by one or more emulation elements / devices (not shown). The emulation devices may be one or more devices configured to emulate one or more, or all, of the functions described herein. For example, the emulation devices may be used to test other devices and / or to simulate network and / or WTRU functions.

[0083] The emulation devices may be designed to implement one or more tests of other devices in a lab environment and / or in an operator network environment. For example, the one or more emulation devices may perform the one or more, or all, functions while being fully or partially implemented and / or deployed as part of a wired and / or wireless communication network in order to test other devices within the communication network. The one or more emulation devices may perform the one or more, or all, functions while being temporarily implemented / deployed as part of a wired and / or wireless communication network. The emulation device may be directly coupled to another device for purposes of testing and / or may performing testing using over-the-air wireless communications.

[0084] The one or more emulation devices may perform the one or more, including all, functions while not being implemented / deployed as part of a wired and / or wireless communication network. For example, the emulation devices may be utilized in a testing scenario in a testing laboratory and / or a non-deployed (e.g., testing) wired and / or wireless communication network in order to implement testing of one or more components. The one or more emulation devices may be test equipment. Direct RF coupling and / or wireless communications via RF circuitry (e.g., which may include one or more antennas) may be used by the emulation devices to transmit and / or receive data.

[0085] The development of international mobile telecommunications (IMT) for 2030 and beyond is expected to enable new use cases and applications with high data rate and low latency, which will benefit from large contiguous bandwidths potentially up to tens of GHz. This suggests the need to consider spectrum in higher frequency (HF) ranges above 92 GHz as a complement to the use of lower frequency band. One of the promising solutions is the potential to leverage advanced modulation schemes to overcome RF impairments at high frequencies to achieve better performance.

[0086] In HF, radio impairments such as power amplifier (PA) efficiency and phase noise (PN) are critical issues for wireless systems operating in HF ranges. For example, PA efficiency is less than 15% in sub-THz when operating central frequency > 100 GHz. Due to PA's intrinsic inefficiencies, the RF power section consumes up to 65% of the overall power budget. PN variance increases 6dB when the central frequency is doubled. For example, PN is expected to increase by 6 dB at 140 GHz than at 70 GHz. Due to limitations of the state-of-the-art analog to digital converter (ADC) techniques, high sampling rate with high resolution simultaneously is hard to achieve in HF.

[0087] In HF (e.g., sub-THz / THz), the effect of PN from a local oscillator on the waveform can be observed as a combination of two separate processes: a “slow” one, and a “fast” one. The effects of “slow” PN can typically be compensated at the receiver (e.g., using phase tracking reference signal (PT-RS)) whereas compensating the effects of “fast” PN are harder. Fast variations appearing in the flat part of the phase noise spectra cannot be effectively compensated in the reception and remain as the dominant phase noise power after compensation due to the wide signal bandwidth. This “fast” PN phenomenon is not a major issue in the lower frequency bands as it is unnoticeable. However, “fast” PN becomes a major issue in HF because fast variations appearing in the flat part of the phase noise spectra cannot be effectively compensated in the reception and remain as the dominant phase noise power after compensation due to the wide signal bandwidth.

[0088] The phase noise in HF range (e.g., up to 200 GHz) may be analyzed. The analysis also shows that the measured signal to noise power ratio (SNR) is always limited by the PN (e.g., residual, or remaining standard deviation) so we call this offset is PN-limited SNR in HF. In addition, the PN-limited SNR is a function of the PN variance (e.g., residual PN variance). The PN-limited SNR results in WTRU may not measure the SNR such that PN-limited SNR degrades the performance especially for the higher quadrature amplitude modulation (QAM) modulation cases.

[0089] There are two constellation shaping (OS) techniques having been studied. The first is geometric constellation shaping (GCS) and the second is probability constellation shaping (PCS).

[0090] GCS retains the same modulated symbols and probability as the regular QAM but distance between modulated symbols can be modified (e.g., nonuniform constellations). For geometric shaping, circular amplitude and phase shift keying (APSK) constellations are typically used. These are constellationdesigns that have various amplitude levels (e.g., possibly non-uniformly spaced), forming multiple circles in the 2D complex plane.

[0091] These highlight that GCS can be introduced for NR advanced or 6G for SC waveform (e.g., single carrier frequency domain equalizer (SC-FDE)) to combat severe radio impairments in HF and enable two possible use cases:

[0092] For downlink (DL), PN robust modulation schemes can enhance spectral efficiency (e.g., requiring less PT-RS) and may relieve the requirement for higher sampling rate (e.g., equivalent to subcarrier spacing in OFDM) for single carrier waveform, especially for DL. In addition, the PN robust modulation schemes can adopt to various PN variance / PN offset.

[0093] A low peak to power ratio (low-PAPR) signal contributes to cost efficiency enhancements or cell coverage. In addition, low PAPR modulation scheme can enhance the power efficiency in HF, especially for uplink (UL) by having less power backoff in PA operation.

[0094] Another constellation shaping technique is using PCS. PCS is to alter the uniform distribution of a constellation (e.g., usually pulse amplitude modulations (PAMs) or rectangular QAMs)) to a non-uniform distribution such that some of constellation has higher probability than others. The PCS shaping encoder changes the occurrence of constellation symbols such that the low-energy inner constellation symbols are transmitted more frequently than high-energy outer constellation symbols. These probabilities can be optimized through the shaping parameter. For example, PCS can adjust some higher amplitude constellation points with lower probability thus the PAPR can be reduced and utilize the PA efficiency.

[0095] The other advantage of PCS is the fine granularity in capacity. PCS can design a certain modulation order (e.g., 64 QAM) and apply probabilistic shaping to change the number of transmitted bits per symbol with fine granularity.

[0096] In various embodiments, multiple modulation schemes are introduced and supported in a WTRU for wireless communications. For example, dynamic switching of modulation schemes is described and supported without increasing system overhead and complexity.

[0097] In some examples, a WTRU may need to combat dynamic nature of RF impairments due to the operating conditions and deployment scenarios in the HF. For example, switching between transmission and reception points (TRPs) may result in the WTRU experiencing different RF impairment conditions. If multiple modulation schemes are introduced, the WTRU may assist the network to determine a preferred modulation scheme (MS) scheme from a set of modulation schemes (e.g., M-ary amplitude and phase-shift keying (APSK)) to achieve the optimal or enhanced performance. Due to the property of high PN in HF, achieved overall SNR is always less than the SNR budget given for the phase noise. Therefore, WTRU assisting the network to minimize this SNR gap (e.g., generated due to high PN) may be desired.

[0098] One or more methods and procedures discussed herein related to dynamic switching of modulation schemes. For example, one or more following embodiments may include using configurable modulation and coding scheme (MOS) list(s), PT-RS pattern association with modulation schemes, indication of preferred modulation scheme for downlink transmission (e.g., with channel; state information (CSI) report), modulation specific channel quality indicator (CQI), or indication of preferred modulation scheme for uplink transmission.

[0099] In an example, one or more modulation schemes may include using geometric constellation shaping (e.g., M-APSK) for overcoming RF impairment and enhancing performance in HF for single-carrier (e.g., SC-FDE) waveform. In an example, a WTRU may report one or more (e.g., a set of) supported modulation schemes to network with the associated parameters (e.g., modulation order), and the WTRU may receive configuration associated with the one or more modulation schemes based on reported WTRU capabilities. The network may dynamically signal the modulation scheme to the WTRU via an indication of modulation and coding scheme.

[0100] In an example, a MS may include one or more of the following operations or processes. A WTRU may report a supported set of modulation schemes to the network. The WTRU may receive a configuration from the network with a set of modulation scheme and the associated parameters. The WTRU may receive physical downlink shared channel / physical uplink shared channel (PDSCH / PUSCH) configuration. The PDSCH / PUSCH configuration may include one or more of the following. The PDSCH / PUSCH configuration may include a set of modulation schemes and associated parameters (e.g., PT-RS pattern, target code rate, etc.). The PDSCH / PUSCH configuration may include configurations for one or more MCS table(s). One or more entries in an MCS Table can be (re-)configured so that they correspond to a new modulation scheme. Example sets of parameters that can be configured for an MCS table entry may include the following examples. Example sets of parameters may include MCS index and MS. Example sets of parameters may include MCS index, MS, and modulation order. Example sets of parameters may include MCS index, MS, modulation order, and PT-RS pattern. Example sets of parameters may include MCS index, MS, modulation order, (new) target code rate (R), and PT-RS pattern. The PDSCH / PUSCH configuration may include an association between one or more RNTI(s) and one or more MCS table(s). The PDSCH / PUSCH configuration may include the use of MAC-CE for the indication of multiple MCS tables where the MCS table is associated with a modulation scheme, or for the indication of the en abl ing / disabl ing and reconfiguration of the MCS table. The PDSCH / PUSCH configuration may include using RNTI for the indication to disable or enable the configuration list for a configurable MCS table or for the indication of Multiple MCS tables. The PDSCH / PUSCH configuration may include using MAC-CE + RNTI for the indication of different MCS tables where each MCS table is associated with a MS and RNTI may be usedfor the indication of different MCS tables where are associated with the same MS but with different parameters like modulation order and target code rate.

[0101] The WTRU may receive a downlink control information (DCI) with a “updated’’ modulation scheme based on the determined MCS table and the indicated MCS index. The WTRU may determine, from a row in a selected MCS table, the modulation scheme, including associating parameters (e.g., the constellation associated to a PT-RS pattern, etc.). If the selected MCS table is a configurable MCS table and the signaled MCS index is one of indices in the reconfigured MCS list, then WTRU may use the configurable MCS list for the determination of modulation scheme, order and other parameters (e.g., target code rate, PT-RS pattern etc.). Otherwise, the signaled MCS may be defined in the MCS table (e.g., original MCS table). If the selected MCS table is not a configurable MCS table and it is selected from a set of multiple MCS tables, then WTRU may use the received MCS index with the selected MCS table for the determination of modulation scheme, modulation order and other parameters (e.g., target code rate, PT-RS pattern etc.). If PCS is enabling, then WTRU may use the indicated MCS information like modulation scheme, modulation order, T CR and the symbol probability distributor with PCS encoding or decoding to readjust the effective code rate.The WTRU may calculate the available information bits based on the indicated modulation scheme, modulation order, PT-RS pattern, TCR and other parameters to perform PDSCH reception or PUSCH transmission.

[0102] The WTRU may report the preferred modulation scheme(s) for at least one of DL or UL transmission. For DL, the WTRU may calculate CQI based on the preferred MS and report the preferred MS and CQI to network (e.g., MS + CQI). For DL, the WTRU may report modulation specific CQI, wherein CQI report may be associated with a particular modulation scheme and order (e.g., M-ary APSK). The WTRU may report multiple CQI where each CQI is associated with a specific modulation scheme and order. In SC-FDE, there is no sub-band CQI reporting, therefore, multiple CQI may be supported for modulation specific CQI reports. For UL, the WTRU may indicate the preferred MS via PUSCH. MS may be indicated in MAC with PUSCH, or MS may be appended in uplink control information (UCI) when it is multiplexed in PUSCH (e.g., hybrid automatic repeat request ack / nack (HARQ A / N) + scheduling request (SR) + MS + CSI, CSI + SR + MS). For UL, the WTRU may indicate the preferred modulation scheme via physical uplink control channel. The preferred MS is implicitly indicated in PUCCH resources and multiple PUCCH resources are reserved for different modulation scheme(s), for example one for regular MS (e.g., NR QAM) and the other is for the X MS (e.g., low PAPR MS). Preferred MS and SR may joint transmit (e.g., explicitly joint transmit) on PUCCH format 0 / 1 , for example, MS is transmitted in UCI (e.g., SR + MS).

[0103] The terms R-QAM and X-QAM (e.g., M-ary APSK, differential APSK, etc.) are used as example modulation schemes herein, wherein R-QAM may be a legacy modulation scheme and X-QAM mayrepresent one or more additional modulation schemes (e.g., GCS). However, R-QAM may represent any one or more modulation schemes, including a legacy scheme, GCS, or other. X-QAM represents any one or more modulation schemes, including GCS, PCS, or other.

[0104] More specifically, X-QAM is a modulation scheme taking different approaches for constellation mapping such that the spacing between the constellation amplitude levels is arbitrary (e.g., non-inform constellation). There are several implementations for X-QAM (e.g., differential M-ary APSK modulation, PCS, etc.) In short, any modulation scheme other than R-QAM may be treated as a X-QAM in this disclosure. Hereafter, X-QAM present a modulation scheme which is different than R-QAM.

[0105] Fig. 2 presents an example wherein, APSK may be treated as an example GCS design and the simulation 200 shows that 16

[0412] APSK PAPR outperforms 64 QAM around 1.6 dB, the simulation 210 shows that 64 [4 12 16 32] APSK PAPR outperforms 64 QAM around 1 .6 dB; and the simulation 220 shows that 256 APSK [4 12 16 32 64 128] outperforms 256 QAM around 2 dB in SC-FDE. FIG. 3 presents another example of GCS design, 16 [4 4 44] APSK is a PN robust modulation scheme 300. The bit error rate (BER) of 16 [4 4 4 4] APSK shows having better performance than rectangular QAM at higher SNR 310. In case of SC waveform, the phase noise may change the phase of the constellation point, resulting in random phase rotations on the constellation in a polar circle. To avoid misdetection, the constellation points are at least separated by the RMS of PN in rad / degree in a polar circle.

[0106] For example, two types of modulation scheme may be used for SC waveform in HF. The first type is for low PAPR modulation scheme and the other is PN robust modulation scheme. M-ary APSK (M- APSK) modulation schemes may be used as one of the realizations of GCS. This is because modulate data (e.g., constellation points) using M-APSK with an unequal number of constellation points / modulated symbols on each concentric ring / circle and the number of concentric rings Nc. For example, as shown in FIG. 4, A M = 12-ary APSK with Nc= 4 concentric rings 400. Each ring has uniform 3 constellation points. Therefore, this example M-APSK may be denoted as 12 - [3 3 3 3] APSK which means Nc= 4 concentric rings and each ring has 3 constellation points.

[0107] M-APSK constellations may be composed of Ncconcentric rings (e.g., contours), each with uniformly spaced phase shift keying (PSK) points. In other words, the M-APSK constellation set % may be expressed by Ncsub-constellation sets, and each sub-constellation set hasconstellation points for t ewhere Xi denotes the sub-constellation set of / for the i-th concentric ring and Ncis the total number of concentric rings. Each constellation point in a sub-constellation set / ; can be expressed as:Equation 1 : 1,where rtis the radius of the i-th concentric ring, is the number of constellation points in the i-th concentric ring, < >, is the phase offset of the i-th concentric ring and j = V-T

[0108] The first modulation scheme that can be considered for SC-FDE is low PAPR modulation scheme based on a family of M-APSK with the following rules:

[0109] For a given modulation order / M-ary (e.g., M e {16, 64, 256, 1024}), the number of concentric rings, or amplitude levels, can be equal to Nc= log2M — 2 and concentric rings (e.g., from inside to outside ring) have [L4 12 — - — — ] constellation points when M > 16, otherwise is log2M- 4 222J Hequal to

[0412] when M = 16.

[0110] For example, the number of rings is equal to Nc= 2, 4 and 6 for M = 16, M — 64 and M — 256 APSK, respectively. Table 1 summarizes an example of a low PAPR modulation scheme when modulation order M = 16, M = 64 and M = 256.Table 1 : Low PAPR M-APSK when M=16, 64 and 256

[0111] In an example, if assuming each constellation point is equiprobable, each radius may be determined by the following equations A function is given to determine the maximum mutual information for all constellation points:Equationwhere XM-APSKe low PAPR M-APSK, e.g., 64 - [4, 12, 16, 32] APSK, ak, a1is the Zc-th constellation point and i-th constellation point, respectively and w is the AWGN noise. To obtain the optimum radius for each ring is to search the following optimization equation.Equationwhere p denotes the ratio of the radius of i-th ring to the radius of the first ring, i.e.= — = l, p2= — , ’iri rNc- PNC- —

[0112] FIG. 5 presents example enhanced low PAPR modulation schemes for SC waveform (e.g., SC- FDE). In FIG. 5 (a), an example of 16 - [4, 12] APSK modulation scheme and related constellation points are illustrated in a diagram 500. In FIG. 5 (b), an example of 64 - [4, 12, 16, 32] APSK modulation schemeand related constellation points are illustrated in a diagram 510. In FIG. 5 (c), an example of 256 - [4, 12, 16, 32, 64, 128] APSK modulation scheme and related constellation points are illustrated in a diagram 520.

[0113] In one embodiment, a PN robust modulation scheme may be based on M-APSK with the following rules.

[0114] For a given modulation order e. g. , M G {16, 64, 256, 1024}, the number of concentric ring MNcmay be equal to Nc= — where n e {1, ••• , log2M - A} is an integer and 1 < k < log2M - 1 is a design parameter and the selection of k is dependent on the modulation order. For example, k = 2 for M = 16. For M = 64, the selected value k = 3. The number of constellation points per ring is equal toM_ 2nNc

[0115] For M-APSK PN robust modulation scheme, each M-APSK may have multiple choices for PN robust modulation schemes. The principle is to separate each constellation point in a concentric ring having a deterministic separation in phase. From Equation 2, the phase between each neighbor constellation point in the same concentric ring is equal If the number of constellation points per concentric ring is less,then the phase between each neighbor constellation point in the same concentric ring is enlarged thus it can be more PN robust. For example, when= 8, the phase between neighbor constellation point is equal to - 2 or - 4, respectively. Therefore= 4 is more PN robust than= 8.

[0116] In one embodiment, Table 2 summarizes an example design for a PN robust modulation scheme when modulation order includes M = 16, M = 64, and / or M = 256. In this example design, some possible realization is provided. For example, the number of rings may be equal to Nc= 4 for M = 16, Nc= 8 or 16 for M = 64, and / or Nc= 32 or 64 for M = 256 APSK, respectively.

[0117] For PN robust modulation scheme, each concentric ring assumes having same number ofM constellation points (e.g., the number of constellation points per concentric ring is equal to — for all rings).NcIn this proposal, the number of concentric rings Nccould be different even for the same M-APSK. This enhanced PN robust modulation scheme provides the flexibility to trade-off between spectral efficiency and performance.Table 2: Example design for M-APSK PN robust modulation schemes when M=16, 64 and 256

[0118] FIG. 6 presents a diagram 600 that illustrates an example design of PN robust modulation scheme for 64 - [8, 8, 8, 8, 8, 8, 8, 8] for a SC waveform (e.g., SC-FED). FIG. 6 also presents a diagram 610 of an example design of a PN robust modulation scheme for 64 - [4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4] for a SC waveform (e.g. SC-FED).

[0119] In one embodiment, a PCS scheme may include using a shaping encoder (e.g., constellation shaping encoder) to convert the channel coded bits into shape symbols and each shaped symbol is assigned with a pre-defined uniquely. As shown in FIG. 7 A, an example of a SC-FDE transmitter 700 that operates as a symbol probability distributor that is deployed before performing modulation for PDSCH transmission. The SC-FDE transmitter 700 may include a PCS encoder 702. The SC-FDE transmitter 700 (e.g., the PCS encoder 702) is a function that may be configured to control the constellation distribution and location. The symbol probability may be decided by the pre-defined specification for a symbol probability distributor. For a modulation order M (e.g., 64 QAM), the symbol probability distributor 700 may be assigned with different symbol probability. For example, for simplicity without losing the generality, for a quadrature phase shift keying (QPSK) (e.g., modulation order M = 4) modulation type, the symbol probability may be [0.2, 0.3, 0.3, 0.2] for constellation points {1 , 2, 3, 4} or the symbol probability may be [0.1 , 0.4, 0.4, 0.1] for constellation points {1 , 2, 3, 4}. In short, the symbol probability for a particular modulation order M may have multiple choice.

[0120] The regular M-ary modulator maps a group log2M bits to one of the M-QAM symbols. For example, log2(M = 16) 4 bits may be required for one 16-QAM symbol. When the PCS encoder 702 is enabled in the transmit link to control the symbol probability, redundancy bits may be generated from the output of the SC-FDE transmitter 700 (e.g., the symbol probability distributor) and / or the PCS encoder 702. For example, for one PCS encoder realization, 12 bits is the input of the PCS encoder 702, and the 16 bits is the output of the PCS encoder 702 for 16-QAM. Therefore, the effective bits rate is dropped by a fraction,3 3 e.g., % = 1- - 4 in this case. Hence, the PCS encoder 702 may provide a fractional (e.g., ? = - 4 M-ary QAM3 e.g. 16 x - = 12) QAM in this example design. In other words, the effective transmission bits is less than M-ary QAM.

[0121] In one embodiment, PCS may work for any GCS to further enhance the constellation shaping. For example, PCS may work with X-QAM, e.g., M-ary APSK to further enhance the link performance.

[0122] FIG. 7B illustrates an example of a SC-FDE receiver 710 that includes a PCS decoder 710, and that may be deployed to convert the demodulated (e.g., soft) bits into bits for channel decoder. The PCS decoder 710 may be at the receiver side as shown in FIG. 7B.

[0123] One or more methods and procedures discussed herein related to dynamic switching of modulation schemes. For example, one or more following embodiments may include using configurable MCS list(s), PT-RS pattern association with modulation schemes, indication of preferred modulation scheme for downlink transmission (with CSI report), modulation specific CQI, or indication of preferred modulation scheme for uplink transmission.

[0124] In one embodiment, GCS may enable multiple benefits for SC waveform in HF like the enhancement of the spectral efficiency and increased PA efficiency. The WTRU may monitor the same DCI format (e.g., no DCI size adjustment) for link adaption while new constellations are used in HF for SC waveform, opening a new dimension for link-adaptation for HF via constellation shaping.

[0125] For example, configurable MCS list may avoid using too many MCS tables due to many different modulation scheme combinations and it may switch between different modulation scheme in one MCS table thus reducing the switching MCS table signaling overhead as well. MAC-CE may be used for indication of different modulation scheme and / or MCS tables (e.g., indication of switching MCS tables) to reduce WTRU complexity. MAC-CE and RNTI may jointly be used for the indication of multiple MCS tables to reduce WTRU complexity. WTRU may assist the NW select the preferred modulation scheme for DL and UL to reduce unnecessary signaling overhead for CSI measurement and enhance the performance. Modulation specific CQI reporting refers to modulation scheme reported in CQI feedback from WTRU to gNB / BS.

[0126] Legacy MCS tables may define modulation and coding schemes (MCS) which may comprise combinations of modulation order and coding rate. To enable dynamic switching of modulation schemes and associated parameters, the notion of MCS may be extended to include such parameters. One way to incorporate modulation scheme into legacy MCS tables may be to define multiple MCS tables (e.g., one or more MCS tables per modulation scheme). However, a large number of MCS tables might have to be defined to cover all required combinations of modulation schemes, modulation parameters, PT RS patterns, etc. Also, a large number of RNTIs may be consumed for this purpose. Instead, a more flexible approach is explored here that is based on (re-)configuration of MCS table(s). Herein, the terms MCS table and MCS list are used interchangeably.

[0127] If mcs-EntryList IE is present in PDSCH and / or PUSCH configuration, the WTRU may determine the modulation scheme, modulation order, target code rate, etc., from the configurable MCS list and based on the received MCS index ( / MCS) from DCI to determine the right modulation scheme. For those / MCSnot re-configured or specified in MCS entry list, then WTRU may assume the indicated / MCSis from MCS lists. Below is an example of a PDSCHA configuration that may be implemented by the solutions described herein.

[0128] Similar to the time domain resource allocation (TDRA) table shown above, configurable MCS list may be introduced for PDSCH / PUSCH configuration. In addition, some enhancements are introduced for configurable MCS list. A configurable MCS List(s) may be used for the indication of PN robust and low PAPR modulation schemes in PDSCH / PUSCH configuration as shown in Table 3 below.

[0129] Single or multiple MCS Lists may be configured in PDSCH / PUSCH configuration, and some entries in a MCS list are configurable. For example, a legacy MCS list (e.g., qam256, qam64LowSE) may be configured with an extra information element (IE) (e.g., mcs-EntryList) in PDSCH / PUSCH configuration. In some cases, an MCS entry list IE may indicate some rows in MCS table (e.g., to reconfigure some rows in the original MCS list) for support X-QAM configuration (e.g., low PAPR or PN robust modulation scheme).

[0130] One or more parameter parameters may be configured for an entry (e.g., ZMCS, modulation order, modulation scheme, modulation scheme parameters, target code rate I, PT-RS pattern, PCS enable or disable, the probability for constellation distribution if PCS is enabling, transmit or receiver filter parameters (e.g., roll-off factor), symbol rate, SC-FDE block length, or CP duration). One or more MCS list entry configurations may be used (e.g., { / Mcs > modulation scheme (e.g., R / X-QAM)}; { / MCS, modulation order, modulation scheme (e.g., R / X-QAM)}; { / MCS, modulation order, modulation scheme (e.g., R / X-QAM), PT-RS pattern}; { / M cs, modulation order, modulation scheme (e.g., R / X-QAM), target code rate R, PT-RS pattern}; or { / MCS, modulation order, modulation scheme (e.g., R / X-QAM), target code rate R, PCS probability distribution, PT-RS pattern}; etc.).

[0131] In an example, if a MCS entry is configured with { / MCS, modulation scheme (e.g., R / X-QAM), modulation order, PT-RS pattern}, then when WTRU received / MCSfrom DCI and this / MCShas configured in configurable MCS list, the WTRU can determine the modulation scheme, modulation order and even PT- RS pattern.

[0132] An example of a configurable MCS list is given below:

[0133] An example description of configurable MCS lists {{ / MCs , modulation order, modulation scheme(e.g., R / X-QAM)} is given in Table 3 below. In Table 3, MCS index code points 10, 17 and 18 for a MCS table are reconfigured.Table 3. A configurable MCS lists lmcsfor low PAPR modulation scheme in a MCS Table

[0134] In another example, the WTRU max’ be configured with a set of modulation schemes with modulation order (e.g., based on a set of parameters that may define a modulation scheme for a modulation order, a corresponding range of MCS indices, or by including a modulation scheme identifier in a list of configured schemes). A default modulation scheme may also be associated with a modulation scheme identifier.

[0135] A configuration of an MCS list entry may comprise a modulation scheme identifier.

[0136] In some examples, a configuration of an MCS list entry may invalidate the entry. This may imply that the WTRU does not expect the receive the entry for the corresponding MCS table. The WTRU may determine the number of bits for the MCS index field based on the number of valid entries of an MCS table, or the highest valid MCS index of an MCS table. The DCI size for indication of MCS index may be adopt to the highest valid MCS index of an MCS table when it is less than the original MCS table. In this case, DCI size for PDCCH can be reduced.

[0137] MAC-CE may be used to indicate disabling or enabling a reconfiguration list. For example, MAC- CE is used to enable or disable the reconfigurable MCS table. For example, if a MCS table has a configurable MCS list, the MAC-CE can indicate of this configurable MCS list being enabled or disabled. If the MCS list is disabled by the indication of MAC-CE, then WTRU may assume using the “default” table for look up MCS index and the WTRU may use the received / MCSin DCI to determine the modulation scheme, modulation order, TCR, etc., for PDSCH / PUSCH.

[0138] In another example, a RNTI may be used to indicate enabling or disabling the reconfigurable MCS list for the MCS table. In this example, multiple MCS tables might not need to be defined and the WTRU may be indicated to fall back to a default modulation scheme (e.g., R-QAM), with default MCS table at any time, (e.g., when the WTRU monitors the PDCCH for scheduling PDSCH).

[0139] In NR, RNTI may be used for WTRU to determine which MCS table will be selected. For example, if the WTRU receives a PDSCH resource allocation using DCI format 1_ 1 with the C-RNTI, then the WTRU may select the 256 / 1024 QAM MCS table. Multiple RNTIs may be used for distinguishing multiple MCS tables where MCS table is associated with a MS scheme. Multiple MCS tables designs can be specified for each X modulation scheme (e.g. low PAPR and PN robust scheme) in a separated MCS table as shown in Table 4 and Table 5, respectively. To distinguish multiple MCS tables, an existing implementation is using multiple MCS RNTIs (e.g. each MCS RNTI is mapped to a MCS table). However, this existing implementation may increase WTRU computation complexity when the number of MCS tables is getting large. In addition, switching to different modulation scheme may not require instantaneously via monitoring DCI. However, MAC-CE may be used for the indication of MCS table with the associated modulation scheme.

[0140] For example, as shown in MCS Table 4 and Table 5, MCS Table 4 is for indication of a modulation scheme, e.g., lower PAPR modulation scheme and MCS Table 5 is indication of another modulation scheme, e.g., PN robust modulation scheme. MAC-CE can indicate which MCS table is activated or deactivated.

[0141] MCS and RNTI may be jointly used for the to indicate different MCS tables. For example, RNTI may indicate those MCS table with the same MS but with different target code rate. MAC-CE may be used for the indication of MCS Table but with different MS. For example, the WTRU may be configured with four MCS tables, two with different modulation scheme MCS table (e.g., same or similar to MCS Table 4 and Table 5) and two MCS tables based on default modulation scheme (e.g., R-QAM table such as NR MCS table, and NR low code rate MCS table). MAC-CE may be used for the indication of different modulation scheme table, (e.g., value 0 is used for the indication of the same modulation scheme Table like NR R- QAM table and low code rate R-QAM table, value 1 is used for the indication of Table 4 which is with low PAPR modulation scheme, and value 2 is used for the indication of Table 5 which is with PN robust modulation scheme).Table 4. An example MCS Table with X (e.g., low PAPR) modulation scheme.Table 5. An example MCS Table with X (e.g., PN robust) modulation scheme

[0142] If multiple (e.g., default) MCS tables are configured for a PDSCH / PUSCH configuration (e.g., “qam256”, “qam64LowSE”) MCS tables are configured in IE and the corresponding mcs-Entry IE (e.g., “mcs-Entry_qam256’’, “mcs-Entry_qam64LowS”) are configured as well, then each mcs-Entry IE indicates the configurable lists for each respective MCS table.

[0143] A PT-RS pattern may be configured in an MCS Table configuration and associated with the modulation scheme (e.g., with a PT-RS pattern configuration for an entry of modulation scheme in the proposed MCS table). Unlike existing NR specification, PT-RS pattern / density is a function of modulation order (e.g., higher modulation order implies higher PT-RS density / pattern). However, a modulation scheme (e.g., PN robust) might not require that PT-RS density is a function of modulation order. Therefore, when the WTRU is indicated an MCS index, the corresponding PT-RS configuration may be applied.

[0144] A PT-RS pattern or density can be configured for a particular modulation scheme or for a combination of a modulation scheme and modulation order. When the WTRU is indicated that a modulation scheme (e.g., and modulation order) is applied, the corresponding PT-RS configuration may be determined.

[0145] If a PT-RS (DL) configuration is given (e.g., DL) for modulation order independent constellation scheme:Then the WTRU may use the configured PT-RS configuration for X modulation scheme. Otherwise, WTRU may use the associated PT-RS pattern defined in MCS table or in the reconfigurable MCS list.

[0146] The association between modulation scheme and PT-RS may be specified from a MCS table or be configured in radio resource control (RRC). For example, PT-RS pattern for a modulation scheme may be predefined in the specification. The WTRU may determine the associated PT-RS pattern in the look up tables when a modulation scheme (e.g., low PAPR, or PN robust) is selected. An example PT-RS pattern and the associated modulation scheme is given in Table 6. In this example design, each modulation scheme may be associated with a SC-PT-RS pattern such as number of group and number of PT-RS symbols in a group for SC-FDE waveform.

[0147] For some modulation schemes (e.g., PN robust modulation scheme) PT-RS density is not a function of modulation order. Therefore, PT-RS pattern / densities for those modulation schemes (e.g., PN robust) may be less than NR R-QAM even though they all belong to the same modulation order, for example, as shown in FIG. 8. Therefore, the spectral efficiency may be enhanced through the PN robust modulation scheme. FIG. 8 illustrates an example diagram 800 that shows a higher PT-RS density for NR R-QAM (Baseline), and an example diagram 810 that shows a lower PT-RS density for PN robust modulation scheme, which for instance, includes more PDSCH and / or PUSCH data in a SC-FDE block (e.g., because some resource elements do not need to include PT-RSs, and instead can be used for data).

[0148] If PT-RS pattern is not configured in PDSCH / PUSCH configuration for X-QAM modulation scheme, then the WTRU may select PT-RS pattern when X modulation scheme and modulation order is specified in a MCS tables. It should be appreciated that the row in the MCS table can be also configurable when the MCS table is reconfigurable.Table 6. An example PT-RS pattern associated with modulation scheme (e.g. APSK)

[0149] FIG. 9 illustrates an example PT-RS pattern design 900 for SC-FDE. In Table 7, four groups (Ngro >s= 4) of PT-RS are in a SC-FDE block and each group has 2 PT-RS symbols= 2. If the WTRU knows the number of available symbolsfor PDSCH (or PUSCH) transmission, then the WTRU may determine the number of available of symbols are used for DL reception or UL transmission. For example, as shown in FIG. 9, the number of available symbols for data transmission is equals to 60 - 2 x 4 = 52 symbols 900.

[0150] For example, PT-RS pattern may be specified for single carrier PT-RS configuration: NgPo^for PT-RS design in SC-FDE. For example, an example PT-RS pattern design is given in Table 7.Table 7. Example SC-PT-RS pattern for PT-RS design in SC-FDE

[0151] When multiple modulation schemes and modulation orders are supported in SC-FDE, the WTRU procedure to calculate available information bits in SC-FDE can be discussed. An example WTRU procedure for the determination of the number of data symbols and the information bits Ninf0) with a configured PT-RS pattern in a SC-FDE block is described below.

[0152] In an example, the WTRU is configured with X (e.g., PN robust and low PAPR) modulation schemes for PDSCH / PUSCH reception and transmission. The WTRU receives / monitors DCI for PDSCH / PUSCH MCS (e.g., MCS index) to determine the X modulation scheme, modulation order Qm, target code rate R, etc. The WTRU calculates (e.g., approximately) Ns(number of symbols in a SC-FDE block) based on the associated PT-RS pattern, DM-RS and determine theR ■ Qm■ v, where v is layers (e.g. maximum number of MIMO layers). For example, if PCS is enabled, then Ninf0= Ns■ R ■ Qm- v ■ y where y is a fractional number and it is specified by PCS encoder. The WTRU receives PDSCH or transmit PUSCH using the Qmand R.

[0153] FIG. 10 illustrates an example of a SC-FDE transmitter 1000. FIG. 10 also illustrates an example of a SC-FDE block 1010 that has W symbols / samples and a cyclic-prefix (CP). The number of symbols per SC-FDE block may be determined by SC-FDE sampling rate. For one realization, SC-FDE sampling time / symbol interval Tsmay be determined by the product of the inverse fast Fourier transform / fast Fourier transform (IFFT / FFT) size and subcarrier spacing (SCS), (e.g., 240, 480 KHz). The bandwidth is equal to inverse of sampling time for SC-FDE waveform. For example, let IFFT / FFT size be equal to 4096 with SCS 480 KHz, the sampling time is equal to 1 / 1 .96608 = 0.5086 ns. In a SC-FDE block, if the number of information symbols / samples Ns, the number of PT-RS symbols / samples / Vptrsand the number of DM-RS ^dmrsarewithin the same SC-FDE block, then the sum of Ns, Nptrsand / Vdmrsis less or equal to N.

[0154] In one embodiment, the network may require additional information to determine the preferred modulation scheme from a manageable set of (e.g., APSK) modulation scheme due to the optimal constellation design for geometric shaping dependent on signal to noise ratio / signal to interface plus noise ratio (SNR / SINR) and / or other assistance parameters (e.g., PN variance / PN offset). Therefore, the WTRU may assist network to determine the preferred modulation scheme via measurement. For example, to accurately reflect the actual SNR / SINR condition caused by PN or other CSI information, WTRU may assist network to select or determine the preferred DL MS with CSI report.

[0155] A particular (e.g., longer) training RS (e.g., lower PAPR BPSK sequence) for PN measurement can be specified for SC-FDE waveform when operating at HF. When this particular (e.g., long) training sequence and L1-SINR / CQI report is configured, the WTRU may assume the report the measured L1- SINR / CQI is with PN compensation.

[0156] In an example, a WTRU may determine the preferred modulation scheme based on the following metrics. The WTRU may measure L1-SINR or CQI after PN compensation or taking the impact of PN and PN compensation into account. Alternatively, the WTRU may measure (residual) PN RMS / variance or PN offset.

[0157] In an example, the WTRU may report the feedback to network including or using one or more of the following procedures. The WTRU may report at least one or more of the preferred MS (e.g., M-aryAPSK), or with other feedback metric (e.g, L1-SINR or CQI after performing PN compensation). MS value may be configured as binary or multi-bits (e.g., 0 = R-QAM, 1 = X-QAM). The WTRU may report PN RMS (e.g, quantized to X bits) standalone or report L1-SINR with PN RMS. In some cases, the feedback may be transmitted via PUCCH or PUSCH.

[0158] In an example, based on at least one or more of WTRU report preferred modulation scheme or other parameters, the network may issue (e.g., or transmit) a CQI report request for the WTRU to report CQI based on the reported preferred subset of modulation schemes (e.g., where the subset could be limited to one preferred modulation scheme). In another example, the requested CQI report request by the network may include modulation schemes that may not be part of the WTRU preferred modulation schemes reported by the WTRU.

[0159] In NR, CQI report (e.g, a CSI report) is solely based on R-QAM. Although exiting, NR CQI report can be based on multiple CQI tables (4 tables) which is configured by high layer, those CQI tables still rely on the same modulation scheme (e.g, R-QAM).

[0160] However, when multiple modulation schemes (e.g, X-QAM) are supported, the WTRU may have to point out which modulation scheme (e.g. X-QAM = M-ary APSK) the CQI report is based. Different modulation schemes and modulation orders may be chosen even when the WTRU measures the same L1- SINR. Therefore, modulation scheme specific CQI should be considered and modulation specific CQI reporting benefits network to determine the optimal transmission modulation scheme for a WTRU.

[0161] For the modulation specific CQI report, if a single CQI table is indicated in a CSI-CQI report configuration, the WTRU may calculate CQI based on the indicated CQI table. For example, the (e.g, single) CQI may contain different modulation scheme (e.g, R-QAM and X-QAM) in the same CQI table (e.g, refer to Table 8). If multiple CQI tables are specified in a CSI-CQI report configuration, the WTRU may calculate CQI based on one or more of the indicated CQI tables and send one or more of the following in CQI report(s): Multiple CQI tables can be configured for a CSI report. In SC-FDE, there is no sub-band CQI reporting, therefore, multiple CQI can be supported for modulation specific CQI reports. For example, a 4-bit CQI table for R-QAM and a 3-bit CQI for M-APSK (e.g, refer to Table 9) may be configured; WTRU reports the preferred modulation scheme MS (e.g, based on configured CQI table ID) for a CSI-CQI report (e.g, report the CQI table ID along with CQI index); or WTRU reports all CQI indices that are based on the configured CQI tables, but there is no need to include CQI table ID. For example, if a 4-bit CQI table for R- QAM and a 3-bit CQI for M-APSK (e.g, refer to Table 9) are configured for a CQI report, the WTRU may report 7-bit CQI (e.g., 4-bit for CQI Table 8 and 3-bit for Table 9.Table 8. A 4-bit CQI Table include R-QAM and X-QAMTable 9. A 3-bit CQI Table with X-QAM

[0162] In one embodiment, the network may require additional information to determine the preferred modulation scheme from a manageable set of (e.g., APSK) modulation scheme due to the optimalconstellation design for geometric shaping depends on SNR / SINR and other parameters. Therefore, to reduce feedback overhead and reduce the latency due to reporting and measurement, the WTRU may assist network to select or determine the preferred UL MS.

[0163] In an example, the WTRU may indicate the preferred MS via PUSCH. MS may be indicated in MAC with PUSCH transmission, or MS may be appended in UCI when it is multiplexed in PUSCH (e.g., (HARQ) A / N + SR + MS + CSI, CSI + SR + MS).

[0164] In another example, the WTRU may indicate the preferred MS via PUCCH (e.g., SR-PUCCH). For example, the preferred MS may be implicitly indicated in PUCCH resource. Multiple PUCCH resources are reserved for different modulation scheme(s) (e.g., one for regular MS (e.g., NR QAM) and the other is for the X MS (e.g., low PAPR MS)). In an example, the preferred modulation scheme and SR may (e.g., explicitly) joint transmit on PUCCH format 0 / 1 (e.g., MS is transmitted in UCI (e.g., SR + MS)). In some cases, MS has the lower priority than HARQ A / N and SR, therefore MS may be dropped at a PUCCH occasion.

[0165] In NR, the measured L1-SINR and CQI at the WTRU side is based on no compensation of PN because PT-RS is only transmitted with PDSCH not with CSI-RS. Therefore, the measured L1-SINR and CQI is hardly track with PN. In addition, at operating at lower frequency, the “fast” PN is not significant, so there is no need for the WTRU to perform L1-SINR / CQI with PN compensation. However, when operating at HF, “fast” PN is difficult to be compensated because the PT-RS Nyquist rate is limited to track PN. Therefore, the measured SNR even with PN compensation still shows a gap with the (e.g., true) target SINR.

[0166] In one embodiment, the WTRU may estimate L1-SINR after PN compensation based on a particular training sequence and feedback to the network, then the network may better estimate the achievable SINR. Further, the network may determine the preferred X-modulation scheme based on the achievable SINR for the WTRU to reduce the requirement of PT-RS.

[0167] In one embodiment, the WTRU may measure PN RMS / variance based on a particular training sequence (e.g. a BPSK or QPSK sequence) and report the quantized PN RMS / variance back to network for assistance of network determining the preferred modulation scheme.

[0168] In an example, the particular training sequence for SC-FDE may be based on a longer training sequence, for example, the long training sequence can be configured for the WTRU to perform PN estimation. FIG. 11 presents an example diagram 1100 wherein, the training sequence may last for a period of SC-FDE blocks. When this particular training sequence is configured for a WTRU, the WTRU may utilize the first several SC-FDE blocks for channel estimation, then the WTRU may use the rest of SC-FDE blocks for performing PN estimation once the channel estimation is completed.

[0169] In one embodiment, the PN measurement based on the training sequence may include three stages. The first stage is performing channel estimation, the second stage is the PN estimation, and the third stage is performing PN compensation and measure the residual PN estimation or the compensated SINR. In an example, once the WTRU estimates the PN then WTRU may compensate the RS to perform the L1-SINR and reports to network as the best achievable SINR.

[0170] In one embodiment, PCS may be configured in higher layer RRC with the following configuration IE, for example, for PDSCH configuration:where PCS configuration include the support modulation scheme, order, and symbol probability distribution pattern.

[0171] The symbol probability distribution pattern may be specified for the constellation symbol probability or a PCS encoding scheme for a M-ary QAM scheme. For example, a PCS symbol probability pattern for all constellation symbol from 0 to 15 may be with the probability = {0.1 , 0.1 , 0.1 , 0.1 , 0.1, 0.1, 0.1 , 0.1 , 0.025, 0.025, 0.025, 0.025, 0.025, 0.025, 0.025, 0.025}, or the PCS symbol probability pattern is specified by a PCS encoder specification.

[0172] In some embodiments, PCS may be enabled or disabled based on semi-statistic methods such as RRC signaling, MAC-CE, or based on a dynamic method such as based on DCI

[0173] In an example, PCS may be enabled or disabled based on RRC or MAC-CE. Based on RRC if PCS configuration is present in PDSCH / PUSCH configuration, then WTRU may assume PCS is enabled. If MAC-CE is used for the indication of enabling or disabling PCS even when PCS configuration is present in PDSCH / PUSCH configuration. If PCS enable or disable is based on DCI.

[0174] In another example, PCS may be enabled or disabled based on a bit in DCI that indicates enabling or disabling PCS. In an example, a RNTI may be used for the indication of enabling or disabling PCS.

[0175] If PCS is enabled, the WTRU may still use the indicated MCS index for determination of modulation scheme and / or modulation order for PDSCH / PUSCH.

[0176] In some embodiments, for UL PUSCH, transmit power may be adjusted by a delta quantity if necessary. For example, a WTRU may adjust transmit power by the specified delta (e.g., the transmit delta(2 dB) power offset can be specified between 64 R-QAM and 64 [4, 12 16, 32] APSK modulation scheme). This is because lower PAPR APSK modulation scheme allows having less power backoff.

[0177] In an example, when the WTRU is configured with X-modulation scheme, the WTRU may adjust the transmit power with a power offset related to the same modulation order of R-QAM. For example, when the WTRU is enabled with PCS, the WTRU may adjust the transmit power offset with a power offset related to the same modulation order of R-QAM. For example, if PCS is enabled for 64 R-QAM, then the WTRU may adjust the transmit power with an offset related to 64 R-QAM without PCS.

[0178] In various embodiments, the WTRU is indicated with X-modulation scheme and the WTRU makes determination of transmit / receive (Tx / Rx) symbols and information bits.

[0179] FIG 12. Illustrates the WTRU procedure 1200 that may be performed by a WTRU to determine the number of data symbols and information (e.g., or information bits). At 1202, the WTRU is configured with a PDSCH and / or PUSCH configuration. The configuration may include a PT-RS pattern for X-QAM. For instance, the configuration may include a single (e.g., configurable) MCS table or multi-MCS tables and an associated PT-RS density for R-QAM and / or X-QAM. At 1204, the WTRU monitors for DCI for PDSCH / PUSCH MCS (e.g., MDC index). At, 1206 the WTRU is configured to determine if GCS is enabled. When GCS is enabled, at 1208, the WTRU uses X-QAM PT-RS pattern. When GCS is not enabled, at 1210, the WTRU uses R-QAM PT-RS pattern. At 1212, the WTRU is configured to determine if PCS is enabled When PCS is enabled, at 1214, the WTRU determines the information bits based on X-QAM PT- RS patterns, modulation order, and target code rate. When PCS is not enabled, at 1216, the WTRU determines the information bits based on XQAM PT-RS patterns, modulation order, target code rate, and PCS information. At 1218, the WTRU is configured to determine whether there is a UL PUSCH Tx. When there is no UL PUSCH Tx, at 1220, the WTRU may be scheduled with a PDSCH Rx. When there in a UL PUSCH Tx, at 1222, the WTRU sends a Tx PUSCH and adjust the Tx power with a delta offset.

[0180] FIG. 13 illustrates the WTRU procedure 1300 that may be performed by a WTRU to report a preferred downlink (DL) modulation scheme with channel quality indicator (CQI) report, according to one or more embodiments. At 1302 the WTRU may receive a particular RS for the WTRU to, measure PN and perform CSI report. At 1304, the WTRU determines whether multiple CQI tables are indicated in the CSI report configuration. When multiple CSI tables are not indicated in the CSI report configuration, at 1306, the WTRU calculates CQI based on the indicated CQI table and reports the CQI index value. When multiple CSI tables are indicated in the CSI report configuration, at 1308, the WTRU calculates multiple CQI reports based on the indicated multiple CQI tables (e.g., CQ1 1 + CQI 2 + ... , or CQI table ID + CQI). At 1310, the WTRU may receive an X-modulation scheme (e.g., PN robust). When the WTRU does not receive X-modulation scheme, at 1312, the WTRU uses R-QAM for PDSCH / PUSCH. When the WTRU does receive X-modulation scheme, at 1314, the WTRU uses X-QAM for PDSCH / PUSCH.

[0181] The WTRU may monitor DCI for obtaining the modulation scheme, modulation order and / or other parameters like target code rate R. The WTRU may determine whether GCS is enabled. If X-modulation scheme is indicated, then WTRU may calculate the available samples / symbols N_S based on PT-RS and DM-RS pattern for X-modulation scheme and modulation order. Otherwise, WTRU may calculate the available sample / symbols based on PT-RS and DM-RS pattern with the indicated modulation order and the default modulation scheme (e.g., R-QAM). If PCS is enabled, then PCS decoder is used for PDSCH and PCS encoder is used for PUSCH. If X-modulation scheme is for PUSCH, then transmission power may be adjusted (e.g., by a pre-configured value such as Y dB).

[0182] In one embodiment, the network may require additional information to determine the preferred modulation scheme from a manageable set of modulation schemes due to the optimal constellation design for geometric shaping dependent on SNR / SINR or other assistance parameters (e.g., residual PN variance / PN offset). To reduce feedback overhead and the latency due to reporting and measurement, the WTRU may assist network to select or determine the preferred DL MS.

[0183] The WTRU procedure that may be performed by a WTRU to report a preferred modulation schemes (e.g., for DL) with CQI. In this example, the procedure for the WTRU to assist choosing the preferred modulation schemes (e.g., for DL transmission) is described herein. The procedure including, the WTRU may report its capability to network with the supported modulation schemes (e.g., a set of modulation schemes, orders, and other associated parameters). The procedure including, the WTRU may receive configurations with (e.g., a set of) modulation schemes and associated information, based on multiple MCS tables and / or configurable MCS list etc. The procedure including, the WTRU may be configured with an RS for performing PN RMS measurement or L1-SINR, CQI report to determine the preferred modulation scheme (e.g. , PN robust modulation scheme). For CQI report, the WTRU may be indicated with the modulation scheme in the CSI report configuration and the CQI report is based on the indicated modulation scheme. The MS indicator may be associated with the MS MCS table like Table 4 and Table 5. For example, MC indicator may have 3 different values ( / '.e., 0, 1 , and 2). Value 1 is used for indication of Table 4, value 2 is used for Table 5, and value 0 is used for the indication of the default QAM (e.g. , R-QAM). The procedure including, the WTRU may determine the preferred modulation scheme based on metrics (e.g., the WTRU may base on the measured L1-SINR or CQI after PN compensation or taking the impact of PN and PN compensation into account, alternatively measured (e.g., residual) PN RMS / variance or PN offset, or a particular (e.g., longer) training RS (e.g. , lower PAPR BPSK sequence) for PN measurement can be specified for SC-FDE waveform operating at HF. When this particular (e.g., long) training sequence and L1 -SINR / CQI or PN RMS report is configured, network and WTRU may assume the report is based on the measurement with PN compensation. The procedure including, the WTRU reports the feedback including one or more of formats. The WTRU may report the preferred MS or with other feedback metric except CQI report (e.g., L1-SINR (e.g., after performingPN compensation) or PN RMS (e.g., quantized to X bits)). Or the WTRU reports modulation specific CQI, CQI report could be based on single CQI report or multiple CQI report. If single CQI report the WTRU reports the CQI index if the CQI table is indicated by network; or the WTRU reports the CQI table ID and CQI index. If multiple CQI report the WTRU reports multiple CQI indices according to the configured multiple CQI table. The feedback can be via PUCCH or PUSCH. The procedure including, the WTRU receives an “updated” MCS indication (e.g., MCS index) from the network confirming reception of the feedback. For example, based on the received MCS index (e.g. by monitoring PDCCH / DCI), the WTRU determines the MS, constellation parameters, associated PT-RS pattern and modulation order, etc. for PDSCH reception / PUSCH transmission.

[0184] In an example, the WTRU may perform the reception of PDSCH / the transmission of PUSCH based on the indicated MS, associated PT-RS pattern, modulation order, TCR and other parameters as explicitly or implicitly receiving the indication.

[0185] FIG. 14A illustrates a procedure 1400 that may be performed by a base station 1402 and a WTRU 1404 to report a preferred modulation scheme of the WTRU (e.g., for UL), where the WTRU 1404 may trigger a SR and report the preferred modulation scheme. At 1412, the WTRU may report its capability to network with the supported modulation schemes (e.g., a set of modulation schemes, orders, and other associated parameters). At 1414, the WTRU receives configurations for (e.g., a set of) modulation schemes and associated information, etc. For example, the configuration of (e.g., a set of) modulation schemes may be based on configurable MCS list or multiple MCS Tables. The procedure including, the WTRU determines the preferred MS from a set of supported modulation schemes. For example, WTRU may use the (e.g., available) power headroom and other assist information (e.g., WTRU battery status) to determine the preferred modulation scheme such as low PAPR modulation scheme. The power headroom calculation may be based on R-QAM initially, and the actual power headroom may be offset by the preferred modulation scheme and modulation order if the preferred modulation scheme and order is not based on R-QAM. At 1416, the WTRU reports the preferred modulation schemes including one or more formats (e.g., the WTRU may indicate the preferred MS via PUSCH, the WTRU may indicate the preferred MS via PUCCH). The procedure including, the WTRU may receive an indication (e.g., MCS index) from the network confirming reception. The WTRU may receive MCS index by monitoring PDCCH / DCI to determine the modulation scheme, associated PT-RS pattern and modulation order, etc. for PDSCH reception / PUSCH transmission. The procedure including, the WTRU performs the following actions: the WTRU performs the reception of PDSCH or the transmission of PUSCH using the signalled modulation scheme, associated PT-RS pattern, modulation order, target code rate and other parameters as explicitly or implicitly signalled. FIG. 14B illustrates an example procedure 1450 that may be performed by a base station 1452 and a WTRU 1454 to report a preferred modulation scheme of the WTRU after a first PUSCH transmission. At 1462, the WTRU may report PUCCH SR to the network.At 1464, the WTRU may receive PDCCH UL grant DCI. At 1466, the WTRU may report PUSCH, the preferred modulation scheme and BSR. At 1468, the WTRU may receive PDCCH, ACK, and switching modulation scheme, etc.

Claims

CLAIMS1 . A wireless transmit / receive unit (WTRU) comprising: a processor configured to: send an indication of a set of modulation schemes supported by the WTRU; receive configuration information indicating at least one modulation and coding scheme (MCS) table, wherein the at least one MCS table indicates a plurality of modulation schemes and respective parameters associated with each modulation scheme of the plurality of the modulation schemes, and wherein each modulation scheme of the plurality of the modulation schemes is associated with a different constellation; receive downlink control information (DCI) that comprises an indication of a configured modulation scheme indicated by the at least one MCS table and respective parameters associated with the configured modulation scheme; receive a downlink transmission based on the configured modulation scheme and the respective parameters associated with the configured modulation scheme; and send an indication of a preferred modulation scheme for downlink transmissions or uplink transmissions based on one or more measurements.

2. The WTRU of claim 1 , wherein the constellation shape comprises rectangular quadrature amplitude modulation (QAM), or differential M-ary amplitude and phase-shift keying (APSK) (M-APSK) modulation.

3. The WTRU of claim 1 , wherein the at least one MCS table comprises a first MCS table and a second MCS table, wherein the first MCS table indicates a first modulation scheme and a first parameters associated with the first modulation scheme, and wherein the second MCS table indicates a second modulation scheme and a second parameters associated with the second modulation scheme.

4. The WTRU of claim 1 , wherein the parameters associated with each modulation scheme comprise a phase tracking reference signal (PT-RS) pattern, constellation parameters, an association of a modulation scheme and corresponding configuration with a modulation order, or a range of MCS indices.

5. The WTRU of claim 1 , wherein the processor is configured to: calculate channel quality indicator (CQI) based on the preferred modulation scheme; andsend an indication of the CQI.

6. The WTRU of claim 1 , wherein the constellation shaping technique comprises probability constellation shaping (PCS) or geometric constellation shaping (GCS).

7. The WTRU of claim 1 , wherein the configuration information comprises at least an MCS index indicating a modulation scheme and associated constellation parameters for a physical downlink shared channel (PDSCH) reception or a physical uplink shared channel (PUSCH) transmission.

8. The WTRU of claim 1 , wherein the configuration information comprises an radio network temporary identifier (RNTI) that schedules one or more of PDSCH or PUSCH transmission.

9. The WTRU of claim 1 , wherein an MCS table of the set of MCS tables is reconfigurable with a configurable list.

10. The WTRU of claim 1 , wherein the processor is configured to: measure phase noise root mean squared variance (PN RMS / variance) based on a particular training sequence and report the PN RMS / variance to a network entity for assistance of the network entity to determine a preferred modulation scheme.

11. A method performed by a wireless transmit / receive unit (WTRU), the method comprising: sending an indication of a set of modulation schemes supported by the WTRU; receiving configuration information indicating at least one modulation and coding scheme (MCS) table, wherein the at least one MCS table indicates a plurality of modulation schemes and respective parameters associated with each modulation scheme of the plurality of the modulation schemes, and wherein each modulation scheme of the plurality of the modulation schemes is associated with a different constellation; receiving downlink control information (DCI) that comprises an indication of a configured modulation scheme indicated by the at least one MCS table and respective parameters associated with the configured modulation scheme; receiving a downlink transmission based on the configured modulation scheme and the respective parameters associated with the configured modulation scheme; andsending an indication of a preferred modulation scheme for downlink transmissions or uplink transmissions based on one or more measurements.

12. The method of claim 11 , wherein the constellation shape comprises rectangular quadrature amplitude modulation (QAM), or differential M-ary amplitude and phase-shift keying (APSK) (M-APSK) modulation.

13. The method of claim 11 , wherein the at least one MCS table comprises a first MCS table and a second MCS table, wherein the first MCS table indicates a first modulation scheme and a first parameters associated with the first modulation scheme, and wherein the second MCS table indicates a second modulation scheme and a second parameters associated with the second modulation scheme.

14. The method of claim 11 , wherein the parameters associated with each modulation scheme comprise a phase tracking reference signal (PT-RS) pattern, constellation parameters, an association of a modulation scheme and corresponding configuration with a modulation order, or a range of MCS indices.

15. The method of claim 11 , further comprising calculating channel quality indicator (CQI) based on the preferred modulation scheme; and sending an indication of the CQI.

16. The method of claim 11 , wherein the constellation shaping technique comprises probability constellation shaping (PCS) or geometric constellation shaping (GCS).

17. The method of claim 11 , wherein the configuration information comprises at least an MCS index indicating a modulation scheme and associated constellation parameters for a physical downlink shared channel (PDSCH) reception or a physical uplink shared channel (PUSCH) transmission.

18. The method of claim 11 , wherein the configuration information comprises a radio network temporary identifier (RNTI) that schedules one or more of PDSCH or PUSCH transmission.

19. The method of claim 11 , wherein an MCS table of the set of MCS tables is reconfigurable with a configurable list.

20. The method of claim 11 , further comprising measuring phase noise root mean squared variance (PN RMS / variance) based on a particular training sequence and reporting the PN RMS / variance to a network entity for assistance of the network entity to determine a preferred modulation scheme.

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