Cyclic shift configuration for PUCCH with π / 2 BPSK modulation

Abstract

Various aspects of the present disclosure generally relate to wireless communications. In some aspects, a user equipment (UE) may cyclically shift a demodulation reference signal (DMRS) sequence based at least in part on a cyclic shift index selected from a cyclic shift index group. The UE may transmit a DMRS corresponding to a shifted DMRS sequence with π / 2 binary phase shift keying (BPSK) modulation on a physical uplink control channel (PUCCH). Numerous other aspects are provided.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 843,151, filed on May 3, 2019, entitled “CYCLIC SHIFT CONFIGURATION FOR PUCCH WITH PI / 2 BPSK MODULATION,” and U.S. Non-Provisional Patent Application No. 16 / 862,077, filed on April 29, 2020, entitled “CYCLIC SHIFT CONFIGURATION FOR PUCCH WITH PI / 2 BPSK MODULATION,” which are hereby expressly incorporated herein by reference.

[0003] Public domain

[0004] Aspects of the present disclosure relate generally to wireless communications and to techniques and apparatus for cyclic shift configuration of a physical uplink control channel (PUCCH) with π / 2 binary phase shift keying (BPSK) modulation. Background Art

[0005] Wireless communication systems are widely deployed to provide various telecommunication services such as telephone, video, data, messaging, and broadcast. Typical wireless communication systems may employ multiple access technologies that can support communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, etc.). Examples of such multiple access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single carrier frequency division multiple access (SC-FDMA) systems, time division synchronous code division multiple access (TD-SCDMA) systems, and long term evolution (LTE). LTE / LTE-Advanced is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP).

[0006] A wireless communication network may include several base stations (BS) that can support communication of several user equipments (UEs). User equipments (UEs) may communicate with base stations (BSs) via downlinks and uplinks. Downlinks (or forward links) refer to the communication link from BS to UE, while uplinks (or reverse links) refer to the communication link from UE to BS. As will be described in more detail herein, BSs may be referred to as B nodes, gNBs, access points (APs), radio heads, transmit receive points (TRPs), new radio (NR) BSs, 5G B nodes, and the like.

[0007] The above multiple access technologies have been adopted in various telecommunication standards to provide common protocols that enable different user equipment to communicate at city, country, region, and even global levels. New Radio (NR) (which may also be referred to as 5G) is an enhancement set to the LTE mobile standard promulgated by the Third Generation Partnership Project (3GPP). NR is designed to better support mobile broadband Internet access by improving spectrum efficiency, reducing costs, improving services, utilizing new spectrum, and using orthogonal frequency division multiplexing (OFDM) (CP-OFDM) with cyclic prefix (CP) on the downlink (DL), using CP-OFDM and / or SC-FDM (e.g., also known as discrete Fourier transform spread OFDM (DFT-s-OFDM) on the uplink (UL), and supporting beamforming, multiple input multiple output (MIMO) antenna technology and carrier aggregation. Other open standards are better integrated to better support mobile broadband Internet access. However, as the demand for mobile broadband access continues to grow, further improvements to LTE and NR technologies are still useful. Preferably, these improvements should be applicable to other multiple access technologies and telecommunication standards that adopt these technologies.

[0008] Overview

[0009] In some aspects, a wireless communication method performed by a user equipment (UE) may include: cyclically shifting a demodulation reference signal (DMRS) sequence based at least in part on a cyclic shift index selected from a cyclic shift index group, wherein a cyclic gap between cyclic shift indices included in the cyclic shift index group is at least 2 and not 6; and transmitting a DMRS corresponding to the shifted DMRS sequence having π / 2 binary phase shift keying (BPSK) modulation on a physical uplink control channel (PUCCH).

[0010] In some aspects, a UE for wireless communication may include a memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to: cyclically shift a DMRS sequence based at least in part on a cyclic shift index selected from a cyclic shift index group, wherein a cyclic gap between cyclic shift indices included in the cyclic shift index group is at least 2 and not 6; and transmit a DMRS corresponding to the shifted DMRS sequence with π / 2 BPSK modulation on a PUCCH.

[0011] In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a UE, may cause the one or more processors to: cyclically shift a DMRS sequence based at least in part on a cyclic shift index selected from a cyclic shift index group, wherein a cyclic gap between cyclic shift indices included in the cyclic shift index group is at least 2 and not 6; and transmit a DMRS corresponding to the shifted DMRS sequence having π / 2 BPSK modulation on a PUCCH.

[0012] In some aspects, an apparatus for wireless communication may include: a device for cyclically shifting a DMRS sequence based at least in part on a cyclic shift index selected from a cyclic shift index group, wherein a cyclic gap between cyclic shift indices included in the cyclic shift index group is at least 2 and not 6; and a device for transmitting a DMRS corresponding to the shifted DMRS sequence having π / 2 BPSK modulation on a PUCCH.

[0013] In some aspects, a wireless communication method performed by a UE may include: receiving an indication of multiple cyclic shift index groups, wherein each cyclic shift index group in the multiple cyclic shift index groups is associated with one or more DMRS sequences; cyclically shifting a DMRS sequence in the one or more DMRS sequences based at least in part on a cyclic shift index included in the cyclic shift index group associated with the DMRS sequence; and transmitting a DMRS corresponding to the shifted DMRS sequence with π / 2 BPSK modulation on a PUCCH.

[0014] In some aspects, a UE for wireless communication may include a memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to: receive an indication of a plurality of cyclic shift index groups, wherein each cyclic shift index group in the plurality of cyclic shift index groups is associated with one or more DMRS sequences; cyclically shift a DMRS sequence in the one or more DMRS sequences based at least in part on a cyclic shift index included in the cyclic shift index group associated with the DMRS sequence; and transmit a DMRS corresponding to the shifted DMRS sequence with π / 2 BPSK modulation on a PUCCH.

[0015] In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a UE, may cause the one or more processors to: receive an indication of a plurality of cyclic shift index groups, wherein each cyclic shift index group in the plurality of cyclic shift index groups is associated with one or more DMRS sequences; cyclically shift a DMRS sequence in the one or more DMRS sequences based at least in part on a cyclic shift index included in the cyclic shift index group associated with the DMRS sequence; and transmit a DMRS corresponding to the shifted DMRS sequence with π / 2 BPSK modulation on a PUCCH.

[0016] In some aspects, an apparatus for wireless communication may include: a device for receiving an indication of multiple cyclic shift index groups, wherein each cyclic shift index group of the multiple cyclic shift index groups is associated with one or more DMRS sequences; a device for cyclically shifting a DMRS sequence among the one or more DMRS sequences based at least in part on a cyclic shift index included in the cyclic shift index group associated with the DMRS sequence; and a device for transmitting a DMRS corresponding to the shifted DMRS sequence having π / 2 BPSK modulation on a PUCCH.

[0017] Aspects generally include methods, apparatus, systems, computer program products, non-transitory computer readable media, user equipment, base stations, wireless communication devices, and processing systems as substantially described herein with reference to and as illustrated in the accompanying drawings and specification.

[0018] The foregoing has broadly outlined the features and technical advantages of examples according to the present disclosure in an effort to make the following detailed description better understood. Additional features and advantages will be described hereinafter. The disclosed concepts and specific examples can be easily used as a basis for modifying or designing other structures for implementing the same purpose as the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. The characteristics of the concepts disclosed herein, both in terms of their organization and method of operation, and the associated advantages will be better understood by considering the following description in conjunction with the accompanying drawings. Each of the accompanying drawings is provided for the purpose of illustration and description and is not intended to define limitations on the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to understand the above-stated features of the present disclosure in detail, the above briefly summarized content may be described in more detail with reference to various aspects, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings only illustrate certain typical aspects of the present disclosure and should not be considered to limit its scope, as the description may allow for other equally effective aspects. The same reference numerals in different drawings may identify the same or similar elements.

[0021] Figure 1 is a block diagram conceptually illustrating an example of a wireless communication network in accordance with various aspects of the present disclosure.

[0022] Figure 2 is a block diagram conceptually illustrating an example of a base station in communication with a user equipment (UE) in a wireless communication network in accordance with various aspects of the present disclosure.

[0023] Figure 3A is a block diagram conceptually illustrating an example of a frame structure in a wireless communication network in accordance with various aspects of the present disclosure.

[0024] Figure 3B is a block diagram conceptually illustrating an example synchronous communication hierarchy in a wireless communication network in accordance with various aspects of the present disclosure.

[0025] Figure 4 is a block diagram conceptually illustrating an example slot format with a normal cyclic prefix in accordance with various aspects of the present disclosure.

[0026] Figure 5 A table illustrating simulated autocorrelation results for, for example, a Demodulation Reference Signal (DMRS) sequence.

[0027] Fig. 6A and 6B is a diagram illustrating one or more examples of cyclic shift configurations for a physical uplink control channel (PUCCH) with π / 2 binary phase shift keying (BPSK) modulation in accordance with various aspects of the present disclosure.

[0028] Figure 7 and 8 is a diagram illustrating example processes performed, for example, by a UE according to various aspects of the present disclosure.

[0029] Detailed Description

[0030] The various aspects of the present disclosure are described more fully below with reference to the accompanying drawings. However, the present disclosure can be implemented in many different forms and should not be interpreted as being limited to any specific structure or function given throughout the present disclosure. Specifically, these aspects are provided to make the present disclosure thorough and complete, and it will convey the scope of the present disclosure to those skilled in the art. Based on the teachings herein, those skilled in the art will appreciate that the scope of the present disclosure is intended to cover any aspect of the present disclosure disclosed herein, whether it is independently or in combination with any other aspect of the present disclosure. For example, any number of aspects set forth herein can be used to implement a device or practice method. In addition, the scope of the present disclosure is intended to cover such devices or methods practiced using supplements or other other structures, functionality, or structures and functionality as the various aspects of the present disclosure set forth herein. It should be understood that any aspect of the present disclosure disclosed herein can be implemented by one or more elements of the claims.

[0031] Several aspects of telecommunication systems will now be presented with reference to various devices and techniques. These devices and techniques will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, algorithms, etc. (collectively referred to as "elements"). These elements can be implemented using hardware, software, or a combination thereof. Whether such elements are implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system.

[0032] It should be noted that although various aspects may be described herein using terminology typically associated with 3G and / or 4G wireless technologies, various aspects of the present disclosure may be applied in communication systems based on other generations, such as 5G and later generations, including NR technology.

[0033] Figure 11 is a diagram illustrating a wireless network 100 in which various aspects of the present disclosure may be practiced. The wireless network 100 may be an LTE network or some other wireless network, such as a 5G or NR network. The wireless network 100 may include several BSs 110 (shown as BS 110a, BS 110b, BS 110c, and BS 110d) and other network entities. A BS is an entity that communicates with a user equipment (UE) and may also be referred to as a base station, NR BS, B node, gNB, 5G B node (NB), access point, transmit receive point (TRP), etc. Each BS may provide communication coverage for a particular geographic area. In 3GPP, the term "cell" may refer to a coverage area of ​​a BS and / or a BS subsystem serving the coverage area, depending on the context in which the term is used.

[0034] A BS may provide communication coverage for a macro cell, a pico cell, a femto cell, and / or another type of cell. A macro cell may cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscriptions. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscriptions. A femto cell may cover a relatively small geographic area (e.g., a residence) and may allow restricted access by UEs associated with the femto cell (e.g., UEs in a closed subscriber group (CSG)). A BS for a macro cell may be referred to as a macro BS. A BS for a pico cell may be referred to as a pico BS. A BS for a femto cell may be referred to as a femto BS or a home BS. In Figure 1 In the example shown in , BS 110a may be a macro BS for macro cell 102a, BS 110b may be a pico BS for pico cell 102b, and BS 110c may be a femto BS for femto cell 102c. A BS may support one or more (e.g., three) cells. The terms "eNB", "base station", "NR BS", "gNB", "TRP", "AP", "B node", "5G NB", and "cell" may be used interchangeably herein.

[0035] In some aspects, the cells may not necessarily be stationary, and the geographic area of ​​the cells may move depending on the location of the mobile BS. In some aspects, the BSs may be interconnected to each other and / or to one or more other BSs or network nodes (not shown) in the wireless network 100 via various types of backhaul interfaces, such as direct physical connections, virtual networks, and / or the like using any suitable transport network.

[0036] The wireless network 100 may also include a relay station. A relay station is an entity that can receive transmissions of data from an upstream station (e.g., a BS or a UE) and send transmissions of the data to a downstream station (e.g., a UE or a BS). A relay station may also be a UE that can relay transmissions for other UEs. Figure 1 In the example shown in , a relay station 110d may communicate with a macro BS 110a and a UE 120d to facilitate communication between the BS 110a and the UE 120d. A relay station may also be referred to as a relay BS, a relay base station, a relay, or the like.

[0037] The wireless network 100 may be a heterogeneous network including different types of BSs (e.g., macro BSs, pico BSs, femto BSs, relay BSs, etc.). These different types of BSs may have different transmit power levels, different coverage areas, and different effects on interference in the wireless network 100. For example, a macro BS may have a high transmit power level (e.g., 5 to 40 watts), while a pico BS, a femto BS, and a relay BS may have a lower transmit power level (e.g., 0.1 to 2 watts).

[0038] A network controller 130 may be coupled to a set of BSs and may provide coordination and control of these BSs. The network controller 130 may communicate with each BS via a backhaul. The BSs may also communicate with each other directly or indirectly, for example, via a wireless or wired backhaul.

[0039] UE 120 (e.g., 120a, 120b, 120c) may be dispersed throughout the wireless network 100, and each UE may be stationary or mobile. UE may also be referred to as an access terminal, terminal, mobile station, subscriber unit, station, etc. UE may be a cellular phone (e.g., a smart phone), a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device or equipment, a biometric sensor / device, a wearable device (smart watch, smart clothing, smart glasses, smart wristband, smart jewelry (e.g., smart ring, smart bracelet)), an entertainment device (e.g., a music or video device, or a satellite radio), a vehicle-mounted component or sensor, a smart meter / sensor, industrial manufacturing equipment, a global positioning system device, or any other suitable device configured to communicate via a wireless or wired medium.

[0040] Some UEs may be considered as machine type communication (MTC) devices, or evolved or enhanced machine type communication (eMTC) UEs. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, etc., which may communicate with a base station, another device (e.g., a remote device), or some other entity. A wireless node may provide connectivity to or to a network (e.g., a wide area network, such as the Internet or a cellular network), for example, via a wired or wireless communication link. Some UEs may be considered as Internet of Things (IoT) devices, and / or may be implemented as NB-IoT (narrowband Internet of Things) devices. Some UEs may be considered as client equipment (CPE). UE 120 may be included inside a housing that houses components of UE 120, such as a processor component, a memory component, and the like.

[0041] In general, any number of wireless networks may be deployed in a given geographic area. Each wireless network may support a specific radio access technology (RAT) and may operate on one or more frequencies. RAT may also be referred to as radio technology, air interface, etc. Frequency may also be referred to as carrier, frequency channel, etc. Each frequency may support a single RAT in a given geographic area to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks may be deployed.

[0042] In some aspects, two or more UEs 120 (e.g., shown as UE 120a and UE 120e) may use one or more sidelink channels to communicate directly (e.g., without using base station 110 as an intermediary to communicate with each other). For example, UE 120 may use peer-to-peer (P2P) communication, device-to-device (D2D) communication, vehicle-to-everything (V2X) protocols (e.g., which may include vehicle-to-vehicle (V2V) protocols, vehicle-to-infrastructure (V2I) protocols, etc.), mesh networks, etc. In this case, UE 120 may perform scheduling operations, resource selection operations, and / or other operations described elsewhere herein as being performed by base station 110.

[0043] As indicated above, Figure 1 are provided as examples. Other examples may differ from those described in Figure 1 The content described.

[0044] Figure 2 It shows that it can be Figure 1 1. Block diagram of a design 200 of base station 110 and UE 120 for one of the base stations and one of the UEs in FIG. Base station 110 may be equipped with T antennas 234a through 234t, and UE 120 may be equipped with R antennas 252a through 252r, where in general T≥1 and R≥1.

[0045] At the base station 110, the transmit processor 220 may receive data for one or more UEs from the data source 212, select one or more modulation and coding schemes (MCS) for each UE based at least in part on a channel quality indicator (CQI) received from the UE, process (e.g., encode and modulate) the data for the UE based at least in part on the MCS selected for each UE, and provide data symbols for all UEs. The transmit processor 220 may also process system information (e.g., for semi-static resource partitioning information (SRPI), etc.) and control information (e.g., CQI requests, grants, upper layer signaling, etc.), and provide overhead symbols and control symbols. The transmit processor 220 may also generate reference symbols for reference signals (e.g., cell-specific reference signals (CRS)) and synchronization signals (e.g., primary synchronization signals (PSS) and secondary synchronization signals (SSS)). The transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on ​​data symbols, control symbols, overhead symbols, and / or reference symbols, where applicable, and may provide T output symbol streams to T modulators (MOD) 232a to 232t. Each modulator 232 may process a respective output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each modulator 232 may further process (e.g., convert to analog, amplify, filter, and up-convert) the output sample stream to obtain a downlink signal. The T downlink signals from modulators 232a to 232t may be transmitted via T antennas 234a to 234t, respectively. According to various aspects described in more detail below, position coding may be used to generate synchronization signals to convey additional information.

[0046] At UE 120, antennas 252a to 252r may receive downlink signals from base station 110 and / or other base stations and may provide received signals to demodulators (DEMODs) 254a to 254r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, downconvert, and digitize) the received signal to obtain input samples. Each demodulator 254 may further process the input samples (e.g., for OFDM, etc.) to obtain received symbols. A MIMO detector 256 may obtain received symbols from all R demodulators 254a to 254r, perform MIMO detection on the received symbols where applicable, and provide detected symbols. A receive processor 258 may process (e.g., demodulate and decode) the detected symbols, provide decoded data for UE 120 to a data sink 260, and provide decoded control information and system information to a controller / processor 280. The channel processor may determine reference signal received power (RSRP), received signal strength indicator (RSSI), reference signal received quality (RSRQ), channel quality indicator (CQI), etc. In some aspects, one or more components of UE 120 may be included in a housing.

[0047] On the uplink, at the UE 120, a transmit processor 264 may receive and process data from a data source 262 and control information from a controller / processor 280 (e.g., for reports including RSRP, RSSI, RSRQ, CQI, etc.). The transmit processor 264 may also generate reference symbols for one or more reference signals. The symbols from the transmit processor 264 may be precoded by a TX MIMO processor 266, if applicable, further processed by modulators 254a through 254r (e.g., for DFT-s-OFDM, CP-OFDM, etc.), and transmitted to the base station 110. At the base station 110, uplink signals from the UE 120 and other UEs may be received by the antenna 234, processed by the demodulator 232, detected by the MIMO detector 236, if applicable, and further processed by the receive processor 238 to obtain decoded data and control information sent by the UE 120. The receive processor 238 may provide decoded data to a data sink 239 and provide decoded control information to a controller / processor 240. The base station 110 may include a communication unit 244 and communicate with the network controller 130 via the communication unit 244. The network controller 130 may include a communication unit 294, a controller / processor 290, and a memory 292.

[0048] In many implementations, as described in more detail elsewhere herein, although aspects of performing or directing the operation of one or more techniques associated with cyclically shifted DMRS for a physical uplink control channel (PUCCH) with π / 2 binary phase shift key (BPSK) modulation generally involve modulator 254 of UE 120 (or modulator 232 of base station 110), TX MIMO processor 266 of UE 120 (or TX MIMO processor 230 of base station 110), transmit processor 164 of UE 120 (or transmit processor 220 of base station 110), or any combination thereof, controller / processor 240 of base station 110, controller / processor 280 of UE 120, and / or Figure 2 Any other component(s) of the base station 110 may also perform or be involved in performing one or more techniques associated with cyclic shift configuration for a physical uplink control channel (PUCCH) with π / 2 binary phase shift keying (BPSK) modulation, as described in more detail elsewhere herein. For example, the controller / processor 240 of the base station 110, the controller / processor 280 of the UE 120, and / or Figure 2 Any other component(s) may perform or direct e.g. Figure 7 The process of 700 Figure 8 The processes 800 of , and / or operations of other processes as described herein. The memories 242 and 282 may store data and program codes for the base station 110 and the UE 120, respectively. As such, the memory 282 of the UE 120 may include a non-transitory computer-readable medium storing one or more instructions for wireless communication, wherein the one or more instructions include: when executed by one or more processors of the UE 120 (e.g., the receive processor 258, the transmit processor 264, and / or the controller / processor 280), the one or more processors execute reference Fig. 6A , 6B , 7 and / or 8 describe one or more instructions of the method(s) described in more detail. Scheduler 246 may schedule UEs for data transmission on the downlink and / or uplink.

[0049] In some aspects, UE 120 may include: means for cyclically shifting a demodulation reference signal (DMRS) sequence based at least in part on a cyclic shift index selected from a group of cyclic shift indices, wherein a cyclic gap between cyclic shift indices included in the group of cyclic shift indices is at least 2 and not 6 (e.g., using controller / processor 280, memory 282, etc.); means for transmitting a DMRS corresponding to a shifted DMRS sequence having π / 2 BPSK modulation on a PUCCH (e.g., using controller / processor 280, transmit processor 264, TX MIMO processor 266, MOD 254, antenna 252, memory 282, etc.); etc. In some aspects, such means may include in conjunction with Figure 2 One or more components of the UE 120 are depicted, such as the modulator 254, the TX MIMO processor 166, the transmit processor 164, the controller / processor 280, etc., or any combination thereof. In some aspects, UE 120 may include: means for receiving an indication of the plurality of cyclic shift index groups, wherein each cyclic shift index group in the plurality of cyclic shift index groups is associated with one or more DMRS sequences (e.g., using antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, controller / processor 280, memory 282, etc.); means for cyclically shifting the DMRS sequence in the one or more DMRS sequences based at least in part on a cyclic shift index included in the cyclic shift index group associated with the DMRS sequence (e.g., using controller / processor 280, memory 282, etc.); means for transmitting a DMRS corresponding to the shifted DMRS sequence with π / 2 BPSK modulation on a PUCCH (e.g., using controller / processor 280, transmit processor 264, TX MIMO processor 266, MOD 254, antenna 252, memory 282, etc.); etc. In some aspects, such means may include in combination Figure 2 One or more components of the UE 120 are depicted, such as the demodulator 254, the MIMO detector 256, the receive processor 258, the modulator 254, the TX MIMO processor 266, the transmit processor 264, the controller / processor 280, etc., or any combination thereof.

[0050] As indicated above, Figure 2 are provided as examples. Other examples may differ from those described in Figure 2 The content described.

[0051] Figure 3AAn example frame structure 300 for frequency division duplex (FDD) in a telecommunication system (e.g., NR) is shown. The transmission timeline for each of the downlink and uplink may be divided into units of radio frames (sometimes referred to as frames). Each radio frame may have a predetermined duration (e.g., 10 milliseconds (ms)) and may be divided into a set of Z (Z ≥ 1) subframes (e.g., with indices 0 to Z-1). Each subframe may have a predetermined duration (e.g., 1 ms) and may include a set of time slots (e.g., in Figure 3A Each subframe 2 is shown m time slots, where m is a parameter design for transmission, such as 0, 1, 2, 3, 4, etc.). Each time slot may include a set of L symbol periods. For example, each time slot may include fourteen symbol periods (e.g., Figure 3A ), seven symbol periods, or another number of symbol periods. In the case where a subframe includes two slots (e.g., when m=1), the subframe may include 2L symbol periods, where the 2L symbol periods in each subframe may be assigned indices 0 to 2L–1. In some aspects, the scheduling unit for FDD may be frame-based, subframe-based, slot-based, symbol-based, etc.

[0052] In some aspects, the subset of symbols included in a time slot may be included in a resource block of the time slot (such as Figure 3A Time slot 0 or time slot 2 shown in m ). In some aspects, one or more UEs may transmit control information, data, reference signals, etc. in one or more resource blocks of a time slot. For example, a UE may transmit a DMRS (e.g., generated by cyclically shifting a DMRS sequence) in a resource block of a PUCCH. Depending on the PUCCH format of the PUCCH, the DMRS may be multiplexed with other DMRS transmitted from other UEs in the resource block. For example, if the PUCCH is PUCCH format 4, up to four DMRS may be multiplexed in the same resource block.

[0053] Although some techniques are described herein in conjunction with frames, subframes, time slots, etc., these techniques may be equally applicable to other types of wireless communication structures, which may be referred to in 5G NR using terms other than "frames," "subframes," "time slots," etc. In some aspects, a wireless communication structure may refer to a periodic, time-bounded communication unit defined by a wireless communication standard and / or protocol. Additionally or alternatively, a wireless communication structure may be used in conjunction with Figure 3A The wireless communication structure configurations are different from those shown in FIG.

[0054] In some telecommunications (e.g., in NR), a base station may transmit a synchronization (SYNC) signal. For example, a base station may transmit a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and the like on the downlink for each cell supported by the base station. The PSS and SSS may be used by the UE for cell search and acquisition. For example, the PSS may be used by the UE to determine symbol timing, and the SSS may be used by the UE to determine a physical cell identifier associated with the base station and frame timing. The base station may also transmit a physical broadcast channel (PBCH). The PBCH may carry some system information, such as system information that supports initial access of the UE.

[0055] In some aspects, a base station may transmit the PSS, SSS, and / or PBCH according to a synchronization communication level (e.g., a synchronization signal (SS) level) including multiple synchronization communications (e.g., SS blocks), as described below in conjunction with Figure 3B as described.

[0056] Figure 3B is a block diagram conceptually illustrating an example SS hierarchy, which is an example of a synchronous communication hierarchy. Figure 3B As shown in FIG. 1 , the SS hierarchy may include an SS burst set, which may include a plurality of SS bursts (identified as SS burst 0 to SS burst B-1, where B is the maximum number of repetitions of the SS burst that may be transmitted by the base station). As further shown, each SS burst may include one or more SS blocks (identified as SS block 0 to SS block (b 最大_SS-1 ), where b 最大_SS-1 is the maximum number of SS blocks that can be carried by an SS burst. In some aspects, different SS blocks may be beamformed differently. A set of SS bursts may be transmitted by a wireless node periodically, such as every X milliseconds, e.g. Figure 3B In some aspects, the SS burst set may have a fixed or dynamic length, such as in Figure 3B is shown as Y milliseconds.

[0057] Figure 3B The SS burst set shown in is an example of a synchronous communication set, and other synchronous communication sets may be used in conjunction with the techniques described herein. Figure 3B The SS blocks shown in are examples of synchronous communications, and other synchronous communications may be used in conjunction with the techniques described herein.

[0058] In some aspects, an SS block includes resources that carry PSS, SSS, PBCH, and / or other synchronization signals (e.g., a third synchronization signal (TSS)) and / or synchronization channels. In some aspects, multiple SS blocks are included in an SS burst, and the PSS, SSS, and / or PBCH may be identical for each SS block across an SS burst. In some aspects, a single SS block may be included in an SS burst. In some aspects, an SS block may be at least four symbol periods in length, with each symbol carrying one or more of a PSS (e.g., occupying one symbol), an SSS (e.g., occupying one symbol), and / or a PBCH (e.g., occupying two symbols).

[0059] In some aspects, the symbols of the SS block are consecutive, such as Figure 3B In some aspects, the symbols of the SS block are non-contiguous. Similarly, in some aspects, one or more SS blocks of an SS burst may be transmitted in contiguous radio resources (e.g., contiguous symbol periods) during one or more time slots. Additionally or alternatively, one or more SS blocks of an SS burst may be transmitted in non-contiguous radio resources.

[0060] In some aspects, the SS burst may have a burst period, whereby each SS block of the SS burst is transmitted by the base station according to the burst period. In other words, the SS blocks may be repeated during each SS burst. In some aspects, the SS burst set may have a burst set periodicity, whereby each SS burst of the SS burst set is transmitted by the base station according to a fixed burst set periodicity. In other words, the SS burst may be repeated during each SS burst set.

[0061] The base station may transmit system information, such as system information blocks (SIBs), on a physical downlink shared channel (PDSCH) in certain time slots. The base station may transmit control information / data on a physical downlink control channel (PDCCH) in C symbol periods of a time slot, where B may be configurable for each time slot. The base station may transmit traffic data and / or other data on the PDSCH in the remaining symbol periods of each time slot.

[0062] As indicated above, Figure 3A and Figure 3B are provided as examples. Other examples may differ from those described in Figure 3A and 3B The content described.

[0063] Figure 4An example slot format 410 with a normal cyclic prefix is ​​shown. Available time-frequency resources may be divided into resource blocks. Each resource block may cover a group of subcarriers (e.g., 12 subcarriers) in a slot and may include several resource elements. Each resource element may cover a subcarrier in a symbol period (e.g., in time) and may be used to send a modulation symbol that may be a real value or a complex value. In some aspects, one or more UEs may transmit control information, data, reference signals, etc. in one or more resource blocks of a slot. For example, a UE may transmit a DMRS (e.g., generated by cyclically shifting a DMRS sequence) in a resource block of a PUCCH. Depending on the PUCCH format of the PUCCH, the DMRS may be multiplexed in the resource block with other DMRS transmitted from other UEs. For example, if the PUCCH is PUCCH format 4, up to four DMRS may be multiplexed in the same resource block.

[0064] For FDD in certain telecommunication systems (e.g., NR), an interleaving structure may be used for each of the downlink and uplink. For example, Q interleavings with indices 0 to Q–1 may be defined, where Q may be equal to 4, 6, 8, 10, or some other value. Each interleaving may include time slots spaced apart by Q frames. Specifically, interleaving q may include time slots q, q+Q, q+2Q, etc., where q∈{0,…,Q–1}.

[0065] The UE may be located within the coverage of multiple BSs. One of these BSs may be selected to serve the UE. The serving BS may be selected based at least in part on various criteria such as received signal strength, received signal quality, path loss, etc. The received signal quality may be quantified by a signal-to-noise-interference ratio (SNIR), or a reference signal received quality (RSRQ), or some other metric. The UE may operate in a strong interference scenario, in which the UE may observe severe interference from one or more interfering BSs.

[0066] Although aspects of the examples described herein may be associated with NR or 5G technology, aspects of the present disclosure may be suitable for use with other wireless communication systems. New Radio (NR) may refer to a radio configured to operate according to a new air interface (e.g., an air interface different from that based on Orthogonal Frequency Division Multiple Access (OFDMA)) or a fixed transport layer (e.g., different from Internet Protocol (IP)). In various aspects, NR may utilize OFDM with CP (referred to herein as cyclic prefix OFDM or CP-OFDM) and / or SC-FDM on the uplink, may utilize CP-OFDM on the downlink and include support for half-duplex operation using time division duplex (TDD). In various aspects, NR may, for example, utilize OFDM with CP (referred to herein as CP-OFDM) and / or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) on the uplink, may utilize CP-OFDM on the downlink and include support for half-duplex operation using TDD. NR may include enhanced mobile broadband (eMBB) services targeting wide bandwidth (e.g., 80 megahertz (MHz) and above), millimeter wave (mmW) targeting high carrier frequencies (e.g., 60 gigahertz (GHz)), massive MTC (mMTC) targeting non-backward compatible MTC technologies, and / or mission critical services targeting ultra-reliable low latency communications (URLLC) services.

[0067] In some aspects, a single component carrier bandwidth of 100 MHz may be supported. NR resource blocks may span 12 subcarriers with a subcarrier bandwidth of 60 or 120 kilohertz (kHz) over a duration of 0.1 milliseconds (ms). Each radio frame may include 40 slots and may have a length of 10 ms. Thus, each slot may have a length of 0.25 ms. Each slot may indicate a link direction (e.g., DL or UL) for data transmission and the link direction for each slot may be switched dynamically. Each slot may include DL / UL data and DL / UL control data.

[0068] Beamforming may be supported and the beam direction may be dynamically configured. MIMO transmission with precoding may also be supported. MIMO configuration in DL may support up to 8 transmit antennas (multi-layer DL transmission with up to 8 streams) and up to 2 streams per UE. Multi-layer transmission with up to 2 streams per UE may be supported. Aggregation of multiple cells may be supported using up to 8 serving cells. Alternatively, NR may support different air interfaces other than OFDM-based interfaces. NR networks may include entities such as central units or distributed units.

[0069] As indicated above, Figure 4 are provided as examples. Other examples may differ from those described in Figure 4 The content described.

[0070] The UE may transmit control information and / or data to the BS on the PUCCH. The control information and / or data may include a scheduling request (SR) for a physical uplink shared channel (PUSCH) resource, hybrid automatic repeat request (HARQ) information (e.g., an acknowledgement (ACK) or negative acknowledgement (NACK) of a downlink communication), channel quality indicator (CQI) information, channel state information (CSI) report, etc. The UE may transmit control information and / or data in one or more uplink communications (e.g., uplink control information (UCI) communication) on the PUCCH.

[0071] To facilitate the BS to demodulate the uplink communications, the UE may also transmit a DMRS to the BS on the PUCCH. The DMRS may include a reference signal that the BS may use to estimate the channel properties of the PUCCH. The BS may perform one or more measurements of the DMRS and may determine whether the results of the one or more measurements meet a corresponding threshold for successful DMRS reception. If the BS determines that the DMRS is successfully received, the BS may continue to demodulate and decode the uplink communications.

[0072] In addition, the BS may use the DMRS transmitted from multiple UEs to distinguish and separate signals from different UEs transmitted on a PUCCH using the same time domain and / or frequency domain resources. In this case, the UEs may generate the DMRS by modulating a binary sequence (which may be referred to as a DMRS sequence), shifting (e.g., cyclically shifting) the DMRS sequence based at least in part on a corresponding cyclic shift index, performing a discrete Fourier transform (DFT) on the shifted DMRS sequence, mapping the elements included in the DMRS sequence to corresponding tones in a resource block (RB), and modulating the tones (e.g., using CP-OFDM and / or another type of modulation). The DMRS sequence may include an initial sequence or seed sequence containing various types of sequences, such as a Zadoff-Chu sequence, a computer-generated binary sequence, a Gold sequence (or Gold code), and the like. In some cases, the DMRS sequence that the UE may use to generate the DMRS may be selected based at least in part on the format of the PUCCH (e.g., PUCCH formats 1, 2, 3, 4, etc.). Furthermore, the UE may select the cyclic shift index from a group of cyclic shift indices based at least in part on an orthogonal cover code index (occ-index) associated with the UE.

[0073] When used with certain types of DMRS sequences, certain cyclic shift index groups can result in good autocorrelation performance (e.g., can result in relatively low autocorrelation between shifted versions of a DMRS sequence). For example, in 3GPP Release 15, a group of cyclic shift indices (0, 3, 6, 9) has been selected for use with a length-12 DMRS sequence of PUCCH format 4, which may include multiple quadrature phase shift keying (QPSK) symbols. When used with a Release 15 length-12 DMRS sequence, this cyclic shift index group has been shown to produce zero autocorrelation because the DMRS sequence is generated in the frequency domain and is frequency flat (e.g., the amplitude of the values ​​in the DMRS sequence is flat across different tones). For example, when used with a Release 15 length-12 DMRS sequence of PUCCH format 4, cyclic shift indices (0, 3, 6, 9) can produce autocorrelation values ​​for a DMRS sequence of (1, 0, 0, 0). In other words, versions of a DMRS sequence that have been cyclically shifted using respective cyclic shift indices that are separated by greater than zero (eg, the cyclic shifts are not the same) have zero autocorrelation.

[0074] Other DMRS sequences may be developed to provide increased coverage for UEs in a cell relative to the DMRS sequences of Release 15 for PUCCH format 4. For example, DMRS sequences based at least in part on a π / 2 BPSK-modulated Gold sequence and / or a π / 2 BPSK-modulated computer-generated binary sequence of various lengths may be used to improve cell coverage, particularly for UEs at the cell edge. For a π / 2 BPSK-modulated DMRS sequence, a bit b(i) is mapped to a complex-valued modulation symbol d(i) according to

[0075]

[0076] The DMRS sequences may be modulated in the time domain so that they have a low peak-to-average power ratio (PAPR) relative to the Release 15 DMRS sequences of PUCCH format 4. Accordingly, the DMRS sequences allow the UE to transmit the DMRS generated from the DMRS sequences at a greater transmit power relative to the DMRS generated from the Release 15 DMRS sequences of PUCCH format 4. However, the DMRS sequences are not flat in the frequency domain.

[0077] Figure 5 Table 500 illustrates example simulation autocorrelation results for 30 different length-12 DMRS sequences for PUCCH transmissions based at least in part on a computer-generated binary sequence for π / 2 BPSK modulation. Table 1 below illustrates example length-12 binary sequences used to generate length-12 DMRS sequences.

[0078]

[0079]

[0080] Table 1

[0081] Table 500 indicates that the average autocorrelations of 30 DMRS sequences using cyclic shift indexes (0, 3, 6, 9) for PUCCH are (1, 0.144, 0.278, 0.144), respectively. Therefore, the example simulation results shown in Table 500 indicate that the cyclic shift indexes (0, 3, 6, 9) may result in poor autocorrelation performance when used with a π / 2 BPSK modulated DMRS sequence for PUCCH format 4. The unexpected poor autocorrelation performance may be due to the difference between the DMRS multiplexing structure and the data multiplexing structure of PUSCH and PUCCH (for example, because PUCCH has an orthogonal data structure and PUSCH has an overlapping data structure), may be due to a π / 2 BPSK modulated DMRS sequence that is flat in the frequency domain, etc.

[0082] Specifically, the four DMRSs may first be separated in the frequency domain using different frequency combs (e.g., if four UEs transmit DMRS on the same resource, two of the four UEs may use even-numbered frequencies, while the other two UEs may use odd-numbered frequencies). Thus, on the same frequency modulation set, 2 UEs are supported, instead of 4 UEs. Thus, the interference to PUSCH caused by using a cyclically shifted version of the DMRS sequence may be less than the interference to PUCCH (e.g., because two UEs using the same frequency modulation set for PUSCH are compared to four UEs using the same frequency modulation set for PUCCH).

[0083] Furthermore, previous use of PUSCH may have shown that non-orthogonality may not result in intolerable degradation of DMRS performance. It is expected that for PUCCH (which provides orthogonality), DMRS performance may be better relative to PUSCH because for PUSCH, data from different UEs may occupy the same tone set, while for PUCCH format 4, data for different UEs will occupy different tone sets and be orthogonal to each other. However, as Figure 5As shown in Table 500 in, the performance of PUCCH transmissions is more sensitive to non-orthogonal DMRS than the performance of PUSCH. In addition, the reliability parameters for PUSCH and PUCCH may be different. For example, PUCCH transmissions may rely on higher reliability than PUSCH transmissions (e.g., PUSCH may rely on a block error rate of 0.1, while PUCCH may rely on a block error rate of 0.001). As a result of these differences, the orthogonality of DMRS between different UEs has less impact on the performance of PUSCH transmissions than PUCCH transmissions, because the bottleneck of performance lies in the data portion, while PUCCH relies on higher reliability. Although it may have been previously assumed that the implementation of PUSCH could be reused for PUCCH, further research indicates that a redesign of the cyclic shift of PUCCH can be implemented to improve DMRS performance in PUCCH.

[0084] Poor autocorrelation performance between shifted versions of a DMRS sequence used with π / 2 BPSK modulation may in turn result in reduced orthogonality between DMRSs generated from the shifted versions of the DMRS sequence. Since PUCCH format 4 allows multiplexing of DMRSs transmitted by multiple UEs in the same resource block (RB), reduced orthogonality between DMRSs may result in performance degradation of the multiplexed DMRSs, which in turn may result in the BS being unable to demodulate and / or decode the corresponding uplink transmission.

[0085] Some aspects described herein provide techniques and apparatus for cyclic shift configuration of a PUCCH with π / 2 BPSK modulation. In some aspects, a BS may configure a cyclic shift index group for use with one or more DMRS sequences modulated using π / 2 BPSK modulation. The BS may transmit an indication of the cyclic shift index group to a UE (e.g., in a signaling communication), and the UE may select a cyclic shift index from the cyclic shift index group for shifting a DMRS sequence to generate a DMRS that may be transmitted to the BS using π / 2 BPSK modulation. The BS may configure the cyclic shift index group so that the cyclic shift indexes included in the group are selected to provide good autocorrelation performance with one or more DMRS sequences (e.g., relative to the cyclic shift indexes (0, 3, 6, 9) used in Release 15). For example, the BS may configure a cyclic shift index group that will be used by the UE to shift a plurality of different DMRS sequences (e.g., the DMRS sequences illustrated in Table 1 above) such that the gaps (e.g., cyclic gaps) between the cyclic shift indexes included in the group are greater than 2, and such that the gaps between the cyclic shift indexes are not 6, which effectively prevents the use of cyclic shift index 6 (e.g., the cyclic shift index with the highest average autocorrelation). As another example, the BS may configure corresponding cyclic shift index groups for different DMRS sequences (e.g., based at least in part on Figure 5 ) such that the cyclic shift index with the lowest autocorrelation is selected.

[0086] In this way, the configured cyclic shift index group can reduce the autocorrelation of the π / 2 BPSK modulated DMRS sequence relative to the cyclic shift index (0,3,6,9) that has been selected for the Release 15 DMRS sequence for PUCCH format 4. This increases the orthogonality of the DMRS generated based at least in part on the π / 2 BPSK modulated DMRS sequence, thereby improving the ability of the UE to multiplex the DMRS for PUCCH format 4.

[0087] Fig. 6A and 6B 6 is a diagram illustrating one or more examples 600 of cyclic shift configurations for PUCCH with π / 2 BPSK modulation in accordance with various aspects of the present disclosure. Fig. 6A and Figure 6B As shown in , example 600 may include communication between a BS (e.g., BS 110) and a UE (e.g., UE 120). The BS and the UE may be included in a wireless network (e.g., wireless network 100). The communication between the BS and the UE may include the UE transmitting an uplink communication to the BS. In some aspects, the UE may transmit the uplink communication on an uplink channel such as a PUSCH, a PUCCH, etc.

[0088] To facilitate the BS to demodulate the uplink communications, the UE may also transmit a DMRS to the BS on the PUCCH. The DMRS may include a reference signal that the BS may use to estimate the channel properties of the PUCCH. The BS may perform one or more measurements of the DMRS and may determine whether the results of the one or more measurements meet a corresponding threshold for successful DMRS reception. If the BS determines that the DMRS is successfully received, the BS may continue to demodulate and decode the uplink communications.

[0089] The UE may generate the DMRS by shifting (e.g., cyclically shifting) the DMRS sequence based at least in part on a cyclic shift index. The cyclic shift index may correspond to the number of positions by which the DMRS sequence is to be shifted (e.g., starting from a base binary sequence or an original binary sequence of the DMRS sequence). For example, a cyclic shift index of 0 may indicate that the DMRS sequence is shifted by 0 positions, a cyclic shift index of 1 may indicate that the DMRS sequence is shifted by 1 position, and so on.

[0090] As in Fig. 6A In the embodiment of the present invention and as shown by reference numeral 602, in order to configure the UE to transmit the DMRS, the BS may transmit to the UE one or more signaling communications indicating one or more parameters for generating and transmitting the DMRS on the PUCCH. The one or more parameters may include an indication of one or more DMRS sequences, one or more cyclic shift index groups, an occ-index associated with the UE, a PUCCH format, etc. In some aspects, the one or more signaling communications may include radio resource control (RRC) communications, media access control (MAC) control element (MAC-CE) communications, downlink control information (DCI) communications, and the like.

[0091] The one or more DMRS sequences may include DMRS sequences of various types and / or lengths. For example, the one or more DMRS sequences may include a π / 2 BPSK modulated Gold sequence (e.g., a Gold sequence to be transmitted using π / 2 BPSK modulation), a π / 2 BPSK modulated computer-generated binary sequence (e.g., a computer-generated binary sequence to be transmitted using π / 2 BPSK modulation), and the like.

[0092] In some aspects, the DMRS sequence that the UE will use to generate the DMRS may be based at least in part on various factors. In some aspects, the UE may use a DMRS sequence from one or more DMRS sequences indicated in the signaling communication based at least in part on one or more signaling communications that explicitly specify which DMRS sequence the UE will use. In some aspects, the UE may use a DMRS sequence based at least in part on the capabilities of the UE (e.g., the UE's ability to generate a DMRS sequence of a particular type and / or length). In some aspects, the UE may use a DMRS sequence based at least in part on the location of the UE within the cellular cell of the BS (e.g., the UE may use a particular type of DMRS sequence depending on whether the UE is located near the edge or center of the cellular cell), etc. As an example, the BS may configure the UE to use a first DMRS sequence of a first type and / or a first length (e.g., a π / 2BPSK-modulated Gold sequence of 30 bits or longer) when the UE is located near the edge of the cell, and to use a second DMRS sequence of a second type and / or a second length (e.g., a π / 2BPSK-modulated computer-generated binary sequence of 24 bits or shorter) when the UE is located near the center of the cell.

[0093] As in Fig. 6A As further shown in and by reference numeral 604, the UE may identify a cyclic shift index group for a DMRS sequence. In some aspects, the UE may identify the cyclic shift index group from one or more cyclic shift index groups indicated in the one or more signaling communications.

[0094] In some aspects, the one or more cyclic shift index groups may include a single cyclic shift index group. In this case, the one or more signaling communications may indicate a cyclic shift index group to be used with all types of DMRS sequences included in the one or more DMRS sequences. In this case, the UE may select the cyclic shift index from the cyclic shift index group to generate the DMRS. The BS may select the cyclic shift index included in the cyclic shift index group based at least in part on the corresponding average autocorrelation values ​​of all possible cyclic shift indices across the one or more DMRS sequences (or across all possible DMRS sequences). As an example, for Figure 5For an example length-12 DMRS sequence associated with the autocorrelation results illustrated in Table 500 of , the BS may select the cyclic shift index so that the cyclic gap between the cyclic shift index groups included in the cyclic shift index group is at least 2 (e.g., to provide sufficient spacing between cyclic shift indices) and not 6 (e.g., to avoid cyclic shift index 6, which exhibits the highest average autocorrelation). In this case, the BS may select cyclic shift indices (0, 2, 5, 10) or (0, 2, 7, 10) as example groups of cyclic shift indices.

[0095] In some aspects, the one or more cyclic shift index groups may include multiple cyclic shift index groups, and the one or more DMRS sequences may include multiple DMRS sequences. In this case, the one or more signaling communications may indicate that the corresponding cyclic shift index group will be used with the corresponding DMRS sequence and / or a corresponding DMRS sequence subset of the one or more DMRS sequences. The UE may identify the cyclic shift index group based at least in part on the DMRS sequence that the UE will use to generate the DMRS.

[0096] The one or more signaling communications may explicitly indicate an association between a cyclic shift index group in the multiple cyclic shift index groups and one or more DMRS sequences in the multiple DMRS sequences. For example, the one or more signaling communications may indicate a corresponding DMRS sequence index associated with the multiple DMRS sequences, and may explicitly indicate that a cyclic shift index group is to be used with a specific DMRS sequence index. In some aspects, the one or more signaling communications may specify a formula and / or one or more parameters for determining which cyclic shift index group is associated with a specific DMRS sequence. The one or more parameters may include a DMRS sequence index of a DMRS sequence, an occ-index of the UE, and the like.

[0097] In some aspects, the BS may select a cyclic shift index included in a cyclic shift index group of the plurality of cyclic shift index groups based at least in part on a DMRS sequence associated with the cyclic shift index group. The BS may select the cyclic shift index based at least in part on corresponding autocorrelation values ​​of all cyclic shift indexes for the DMRS sequence. For example, the BS may select the cyclic shift index having the lowest autocorrelation for the DMRS sequence while maintaining sufficiently spaced cyclic shift indexes (e.g., a minimum cyclic gap of at least 2). As an example, for a cyclic shift index associated with Figure 5For an example 12-bit length DMRS sequence associated with the autocorrelation results illustrated in Table 500, the BS may select cyclic shift indices (0, 2, 6, 10) as an example group of cyclic shift indices for DMRS sequence index 8 because the resulting cyclic shift index group exhibits zero autocorrelation. As another example, the BS may select cyclic shift indices (0, 2, 5, 10) or (0, 2, 7, 10) as another example group, i.e., an example group of cyclic shift indices for DMRS sequence index 0, because these resulting cyclic shift index groups exhibit zero autocorrelation.

[0098] As in Figure 6B , and as shown by reference numeral 606, the UE may shift the DMRS sequence based at least in part on a cyclic shift index in the cyclic shift index group. In some aspects, the UE may identify the cyclic shift index from the selected cyclic shift index group based at least in part on an occ-index indicated in the one or more signaling communications. For example, if the one or more signaling communications indicate that the PUCCH is PUCCH format 4 (e.g., DMRS from multiple UEs are to be multiplexed into a PUCCH in a single RB), the UE may use the occ-index associated with the UE to perform a lookup in a PUCCH format 4 table or data storage to identify the cyclic shift index from the selected cyclic shift index group.

[0099] In some aspects, the occ-index associated with the UE may be based at least in part on the multiplexing capacity of the PUCCH format 4 configuration for the cyclic shift index group. For example, if the multiplexing capacity configured for PUCCH format 4 of the cyclic shift index group is equal to 4, four DMRS (e.g., from four different UEs) can be multiplexed in the same RB. In this case, the occ-index associated with the UE can be one of the four available occ-indexes corresponding to the corresponding DMRS sequence index. As another example, if the multiplexing capacity configured for PUCCH format 4 of the cyclic shift index group is equal to 2, two DMRS (e.g., from two different UEs) can be multiplexed in the same RB. In this case, the occ-index associated with the UE can be one of the two available occ-indexes corresponding to the corresponding DMRS sequence index. Tables 2 and 3 below illustrate example combinations of multiplexing capacity, occ-index, and DMRS sequence index configured for PUCCH format 4.

[0100]

[0101] Table 2

[0102]

[0103] Table 3

[0104] To shift the DMRS sequence based at least in part on the identified cyclic shift index, the UE may cyclically shift a base binary sequence or an original binary sequence of the DMRS sequence modulated by π / 2 BPSK by a number of positions corresponding to the cyclic shift index. For example, if the selected cyclic shift index is 5, the UE may shift the base binary sequence or the original binary sequence of the DMRS sequence by 5 positions.

[0105] As in Figure 6B , and as further shown by reference numeral 608, the UE may transmit a DMRS corresponding to a shifted DMRS sequence (e.g., a DMRS sequence shifted based at least in part on the identified cyclic shift index). The UE may transmit the DMRS on the PUCCH and using π / 2 BPSK modulation. For example, the UE may map the DMRS sequence to one or more symbols using π / 2 BPSK modulation. In some aspects, if the PUCCH is PUCCH format 4, the UE may transmit the DMRS in an RB together with one or more DMRS transmitted from one or more other UEs multiplexed with the DMRS in the RB.

[0106] In this way, the BS can configure a cyclic shift index group for one or more DMRS sequences modulated using π / 2 BPSK modulation. The BS can transmit an indication of the cyclic shift index group to the UE, and the UE can select a cyclic shift index from the cyclic shift index group for shifting the DMRS sequence to generate a DMRS that can be transmitted to the BS using π / 2 BPSK modulation. The BS can configure the cyclic shift index group so that the cyclic shift index included in the group is selected to provide good autocorrelation performance with the one or more DMRS sequences (e.g., a DMRS sequence of version 15 relative to PUCCH format 4). In this way, the configured cyclic shift index group can reduce the autocorrelation of the π / 2 BPSK modulated DMRS sequence relative to the cyclic shift index (0, 3, 6, 9) selected for the version 15 DMRS sequence of PUCCH format 4. This increases the orthogonality of the DMRS generated by the DMRS sequence based at least in part on the π / 2 BPSK modulated DMRS, thereby improving the ability of the UE to multiplex the DMRS for PUCCH format 4.

[0107] As indicated above, Fig. 6A and 6B is provided as one or more examples. Other examples may differ from those described herein. Fig. 6A and Figure 6B The content described.

[0108] Figure 7 is a diagram illustrating an example process 700, performed, for example, by a UE, in accordance with various aspects of the present disclosure. Example process 700 is an example in which a UE (eg, UE 120) performs operations associated with cyclic shift configuration of a PUCCH with π / 2 BPSK modulation.

[0109] like Figure 7 As shown in , in some aspects, process 700 may include cyclically shifting a DMRS sequence based at least in part on a cyclic shift index selected from a group of cyclic shift indices, wherein a cyclic gap between cyclic shift indices included in the group of cyclic shift indices is at least 2 and not 6 (block 710). For example, the UE (e.g., using modulator 254, transmit processor 264, TX MIMO processor 266, controller / processor 280, memory 282, etc.) may cyclically shift the DMRS sequence based at least in part on a cyclic shift index selected from the group of cyclic shift indices, as described above, for example, with reference to Figure 5 , 6A In some aspects, the cyclic gap between the cyclic shift indices included in the cyclic shift index group is at least 2 and not 6.

[0110] like Figure 7 As further shown in FIG. 7 , in some aspects, process 700 may include transmitting a DMRS corresponding to a shifted DMRS sequence having π / 2 BPSK modulation on a PUCCH (block 720). For example, the UE (e.g., using modulator 254, transmit processor 264, TX MIMO processor 266, controller / processor 280, memory 282, etc.) may transmit a DMRS corresponding to a shifted DMRS sequence having π / 2 BPSK modulation on a PUCCH, as described above, for example, with reference to FIG. Figure 5 , 6A and / or as described in 6B.

[0111] Process 700 may include additional aspects, such as any single aspect or any combination of aspects described below and / or in conjunction with one or more other processes described elsewhere herein.

[0112] In a first aspect, the PUCCH is PUCCH format 4. In a second aspect, alone or in combination with the first aspect, transmitting the DMRS comprises transmitting the DMRS on the PUCCH in a resource block (RB) in which the DMRS is multiplexed with one or more other DMRS transmitted from one or more other UEs. In a third aspect, alone or in combination with one or more of the first and second aspects, process 700 further comprises selecting the cyclic shift index from the group of cyclic shift indices based at least in part on an orthogonal cover code index (occ-index) associated with the UE.

[0113] In a fourth aspect, either alone or in combination with one or more of the first to third aspects, process 700 further includes receiving an indication of the occ-index, and selecting the cyclic shift index from the group of cyclic shift indices includes selecting the cyclic shift index from the group of cyclic shift indices based at least in part on the indication of the occ-index. In a fifth aspect, either alone or in combination with one or more of the first to fourth aspects, receiving the indication of the occ-index includes receiving the indication of the occ-index in at least one of an RRC communication, a MAC-CE communication, or a DCI communication.

[0114] In a sixth aspect, either alone or in combination with one or more of the first to fifth aspects, the cyclic shift index group is associated with a plurality of DMRS sequences, and the plurality of DMRS sequences are at least partially based on corresponding π / 2 BPSK modulated computer-generated binary sequences. In a seventh aspect, either alone or in combination with one or more of the first to sixth aspects, the cyclic shift index group comprises cyclic shift indices (0,2,5,10) or cyclic shift indices (0,2,7,10) for a multiplexing capacity of a PUCCH format 4 configuration equal to 4. In an eighth aspect, either alone or in combination with one or more of the first to seventh aspects, the cyclic shift index group comprises cyclic shift indices (0,5) or cyclic shift indices (0,7) for a multiplexing capacity of a PUCCH format 4 configuration equal to 2.

[0115] although Figure 7 An example block diagram of process 700 is shown, but in some aspects, process 700 may include Figure 7 Additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in the process 700. Additionally or alternatively, two or more blocks of the process 700 may be executed in parallel.

[0116] Figure 8 is a diagram illustrating an example process 800 performed, for example, by a UE in accordance with various aspects of the present disclosure. Example process 800 is an example in which a UE (eg, UE 120) performs operations associated with cyclic shift configuration of a PUCCH with π / 2 BPSK modulation.

[0117] like Figure 8As shown in FIG. 8 , in some aspects, process 800 may include receiving an indication of a plurality of cyclic shift index groups, wherein each cyclic shift index group in the plurality of cyclic shift index groups is associated with one or more DMRS sequences (block 810). For example, the UE (e.g., using demodulator 254, MIMO detector 256, receive processor 258, controller / processor 280, memory 282, etc.) may receive an indication of a plurality of cyclic shift index groups, as described above, for example, with reference to Figure 5 , 6A In some aspects, each cyclic shift index group in the plurality of cyclic shift index groups is associated with one or more DMRS sequences.

[0118] like Figure 8 As further shown in FIG. 8 , in some aspects, process 800 may include cyclically shifting a DMRS sequence of the one or more DMRS sequences based at least in part on a cyclic shift index included in a cyclic shift index group associated with the DMRS sequence (block 820). For example, the UE (e.g., using modulator 254, transmit processor 264, TX MIMO processor 266, controller / processor 280, memory 282, etc.) may cyclically shift the DMRS sequence based at least in part on a cyclic shift index included in a cyclic shift index group associated with a DMRS sequence of the one or more DMRS sequences, as described above, for example, with reference to FIG. Figure 5 , 6A and / or as described in 6B.

[0119] like Figure 8 As further shown in FIG. 8 , in some aspects, process 800 may include transmitting a DMRS corresponding to a shifted DMRS sequence having π / 2 BPSK modulation on a PUCCH (block 830). For example, the UE (e.g., using modulator 254, transmit processor 264, TX MIMO processor 266, controller / processor 280, memory 282, etc.) may transmit a DMRS corresponding to a shifted DMRS sequence having π / 2 BPSK modulation on a PUCCH, as described above, for example, with reference to FIG. Figure 5 , 6A and / or as described in 6B.

[0120] Process 800 may include additional aspects, such as any single aspect or any combination of aspects described below and / or in conjunction with one or more other processes described elsewhere herein.

[0121] In a first aspect, the one or more DMRS sequences are based at least in part on a corresponding π / 2BPSK modulated computer-generated binary sequence. In a second aspect, alone or in combination with the first aspect, the PUCCH is PUCCH format 4. In a third aspect, alone or in combination with the first and second aspects, transmitting the DMRS comprises transmitting the DMRS on the PUCCH in an RB, the DMRS being multiplexed in the RB with one or more other DMRS transmitted from one or more other UEs.

[0122] In a fourth aspect, alone or in combination with one or more of the first to third aspects, process 800 further includes selecting the cyclic shift index from the cyclic shift index group based at least in part on at least one of an occ-index associated with the UE or a DMRS sequence index associated with the DMRS sequence. In a fifth aspect, alone or in combination with one or more of the first to fourth aspects, process 800 further includes receiving an indication of the occ-index, and selecting the cyclic shift index from the cyclic shift index group includes selecting the cyclic shift index from the cyclic shift index group based at least in part on the indication of the occ-index.

[0123] In a sixth aspect, alone or in combination with one or more of the first to fifth aspects, receiving the indication of the occ-index comprises receiving the indication of the occ-index in at least one of RRC communication, MAC-CE communication, or DCI communication. In a seventh aspect, alone or in combination with one or more of the first to sixth aspects, receiving the indication of the plurality of cyclic shift index groups comprises receiving the indication of the plurality of cyclic shift index groups in at least one of RRC communication, MAC-CE communication, or DCI communication.

[0124] In the eighth aspect, alone or in combination with one or more of the first to seventh aspects, the one or more DMRS sequences are associated with corresponding DMRS sequence indices, and process 800 further includes determining that the DMRS sequence is associated with the cyclic shift index group based at least in part on the DMRS sequence index associated with the DMRS sequence, and shifting the DMRS sequence based at least in part on the cyclic shift index included in the cyclic shift index group associated with the DMRS sequence, including at least in part on determining that the cyclic shift index group is associated with the DMRS sequence, thereby shifting the DMRS sequence based at least in part on the cyclic shift index included in the cyclic shift index group.

[0125] In a ninth aspect, either alone or in combination with one or more of the first to eighth aspects, process 800 further includes receiving an indication of a corresponding DMRS sequence based at least in part on at least one of an RRC communication, a MAC-CE communication, or a DCI communication. In a tenth aspect, either alone or in combination with one or more of the first to ninth aspects, process 800 further includes receiving an indication of a corresponding association between each cyclic shift index group in the plurality of cyclic shift index groups, the one or more DMRS sequences in at least one of the following: an RRC communication, a MAC-CE communication, or a DCI communication.

[0126] although Figure 8 An example block diagram of process 800 is shown, but in some aspects, process 800 may include Figure 8 Additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in the process 800. Additionally or alternatively, two or more blocks of process 800 may be executed in parallel.

[0127] The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the precise forms disclosed. Modifications and variations may be made in light of the above disclosure or may be acquired by practice of the various aspects.

[0128] As used herein, the term "component" is intended to be broadly interpreted as hardware, firmware, and / or a combination of hardware and software. As used herein, a processor is implemented with hardware, firmware, and / or a combination of hardware and software.

[0129] As used herein, satisfying a threshold may refer to a value being greater than a threshold, greater than or equal to a threshold, less than a threshold, less than or equal to a threshold, equal to a threshold, not equal to a threshold, etc., depending on the context.

[0130] It will be apparent that the systems and / or methods described herein can be implemented in different forms of hardware, firmware, and / or a combination of hardware and software. The actual dedicated control hardware or software code used to implement these systems and / or methods does not limit the various aspects. Thus, the operation and behavior of these systems and / or methods are described herein without reference to specific software codes—it is understood that software and hardware can be designed to implement these systems and / or methods based at least in part on the description herein.

[0131] Although specific feature combinations are described in the claims and / or disclosed in the specification, these combinations are not intended to limit the disclosure of various aspects. In fact, many of these features can be combined in a manner not specifically described in the claims and / or not disclosed in the specification. Although each dependent claim listed below can be directly subordinate to only one claim, the disclosure of various aspects includes that each dependent claim is combined with each other claim in this group of claims. The phrase quoting "at least one of" a column of items refers to any combination of these items, including single members. As an example, "at least one of a, b or c" is intended to cover: a, b, c, ab, ac, bc, and abc, and any combination with multiple identical elements (for example, aa, aaa, aab, aac, abb, acc, bb, bbb, bbc, cc, and ccc, or any other sorting of a, b and c).

[0132] Elements, actions or instructions used herein should not be interpreted as critical or necessary unless explicitly described as such. Moreover, as used herein, the articles "one" and "a" are intended to include one or more items and can be used interchangeably with "one or more". In addition, as used herein, the terms "set" and "group" are intended to include one or more items (e.g., related items, non-related items, combinations of related and non-related items, etc.), and can be used interchangeably with "one or more". In the case of intending to have only one item, the phrase "only one" or similar language is used. Moreover, as used herein, the terms "having", "containing", "including", etc. are intended to be open terms. In addition, the phrase "based on" is intended to mean "based at least in part on", unless otherwise explicitly stated.

Claims

1. A wireless communication method performed by a user equipment (UE), comprising: cyclically shifting a demodulation reference signal (DMRS) sequence based at least in part on a cyclic shift index selected from a group of cyclic shift indices, wherein the DMRS sequence is modulated in the time domain, and wherein amplitudes of values ​​in the DMRS sequence are not flat across different tones, wherein a cyclic gap between cyclic shift indices included in the cyclic shift index group is at least 2 and not 6; and A DMRS corresponding to a shifted DMRS sequence with π / 2 binary phase shift keying (BPSK) modulation is transmitted on a physical uplink control channel (PUCCH).

2. The method of claim 1, wherein the PUCCH is PUCCH format 4.

3. The method of claim 1 , wherein transmitting the DMRS comprises: transmitting the DMRS on the PUCCH in a resource block (RB), The DMRS is multiplexed in the RB with one or more other DMRSs transmitted from one or more other UEs.

4. The method of claim 1, further comprising: The cyclic shift index is selected from the group of cyclic shift indices based at least in part on an orthogonal cover code index (occ-index) associated with the UE.

5. The method of claim 4, further comprising: receiving an indication of the occ-index; as well as Wherein selecting the cyclic shift index from the cyclic shift index group comprises: The cyclic shift index is selected from the group of cyclic shift indices based at least in part on the indication of the occ-index.

6. The method of claim 5, wherein receiving the indication of the occ-index comprises: receiving the indication of the occ-index in at least one of: Radio Resource Control (RRC) communications, Medium Access Control (MAC) Control Element (MAC-CE) communications, or Downlink Control Information (DCI) communication.

7. The method of claim 1, wherein the cyclic shift index group is associated with a plurality of DMRS sequences, The plurality of DMRS sequences are based at least in part on corresponding π / 2 BPSK modulated computer-generated binary sequences.

8. The method of claim 1, wherein the cyclic shift index group includes cyclic shift indices 0, 2, 5, 10 or cyclic shift indices 0, 2, 7, 10 for a multiplexing capacity of a PUCCH format 4 configuration equal to 4.

9. The method of claim 1, wherein the cyclic shift index group comprises cyclic shift index 0,5 or cyclic shift index 0,7 for a multiplexing capacity of PUCCH format 4 configuration equal to 2.

10. A wireless communication method performed by a user equipment (UE), comprising: receiving an indication of a plurality of cyclic shift index groups, wherein each cyclic shift index group of the plurality of cyclic shift index groups is associated with one or more demodulation reference signal (DMRS) sequences, wherein the DMRS sequences are modulated in the time domain, and wherein amplitudes of values ​​in the DMRS sequences are not flat across different tones; cyclically shifting the DMRS sequence based at least in part on a cyclic shift index included in a group of cyclic shift indices associated with a DMRS sequence of the one or more DMRS sequences; and A DMRS corresponding to a shifted DMRS sequence with π / 2 binary phase shift keying (BPSK) modulation is transmitted on a physical uplink control channel (PUCCH).

11. The method of claim 10, wherein the one or more DMRS sequences are based at least in part on corresponding π / 2 BPSK modulated computer-generated binary sequences.

12. The method of claim 10, wherein the PUCCH is PUCCH format 4.

13. The method of claim 10, wherein transmitting the DMRS comprises: transmitting the DMRS on the PUCCH in a resource block (RB), The DMRS is multiplexed in the RB with one or more other DMRSs transmitted from one or more other UEs.

14. The method of claim 10, further comprising: The cyclic shift index is selected from the group of cyclic shift indices based at least in part on at least one of: an orthogonal cover code index (occ-index) associated with the UE, or A DMRS sequence index associated with the DMRS sequence.

15. The method of claim 14, further comprising: receiving an indication of the occ-index; as well as Wherein selecting the cyclic shift index from the cyclic shift index group comprises: The cyclic shift index is selected from the group of cyclic shift indices based at least in part on the indication of the occ-index.

16. The method of claim 15, wherein receiving the indication of the occ-index comprises: receiving the indication of the occ-index in at least one of: Radio Resource Control (RRC) communications, Medium Access Control (MAC) Control Element (MAC-CE) communications, or Downlink Control Information (DCI) communication.

17. The method of claim 10, wherein receiving the indication of the plurality of cyclic shift index groups comprises: Receiving the indication of the plurality of groups of cyclic shift indices in at least one of: Radio Resource Control (RRC) communications, Medium Access Control (MAC) Control Element (MAC-CE) communications, or Downlink Control Information (DCI) communication.

18. The method of claim 10, wherein the one or more DMRS sequences are associated with corresponding DMRS sequence indexes; as well as Wherein the method further comprises: determining that the DMRS sequence is associated with the group of cyclic shift indices based at least in part on a DMRS sequence index associated with the DMRS sequence; and Wherein shifting the DMRS sequence based at least in part on the cyclic shift index included in the group of cyclic shift indices associated with the DMRS sequence comprises: Based at least in part on determining that the group of cyclic shift indices is associated with the DMRS sequence, the DMRS sequence is shifted based at least in part on the cyclic shift indices included in the group of cyclic shift indices.

19. The method of claim 18, further comprising: Receiving an indication of the corresponding DMRS sequence index based at least in part on at least one of: Radio Resource Control (RRC) communications, Medium Access Control (MAC) Control Element (MAC-CE) communications, or Downlink Control Information (DCI) communication.

20. The method of claim 10, further comprising: receiving an indication of a respective association between each of the plurality of cyclic shift index groups, the one or more demodulation reference signal (DMRS) sequences, in at least one of: Radio Resource Control (RRC) communications, Medium Access Control (MAC) Control Element (MAC-CE) communications, or Downlink Control Information (DCI) communication.

21. A user equipment (UE) for wireless communication, comprising: Memory; as well as one or more processors operatively coupled to the memory, the memory and the one or more processors being configured to: cyclically shifting a demodulation reference signal (DMRS) sequence based at least in part on a cyclic shift index selected from a group of cyclic shift indices, wherein the DMRS sequence is modulated in the time domain, and wherein amplitudes of values ​​in the DMRS sequence are not flat across different tones, wherein a cyclic gap between cyclic shift indices included in the cyclic shift index group is at least 2 and not 6; and A DMRS corresponding to a shifted DMRS sequence with π / 2 binary phase shift keying (BPSK) modulation is transmitted on a physical uplink control channel (PUCCH).

22. The UE of claim 21 , wherein when transmitting the DMRS, the one or more processors are to: transmitting the DMRS on the PUCCH in a resource block (RB), The DMRS is multiplexed in the RB with one or more other DMRSs transmitted from one or more other UEs.

23. The UE of claim 21, wherein the one or more processors are further configured to: The cyclic shift index is selected from the group of cyclic shift indices based at least in part on an orthogonal cover code index (occ-index) associated with the UE.

24. The UE of claim 23, wherein the one or more processors are further configured to: Receiving an indication of the occ-index in at least one of: Radio Resource Control (RRC) communications, Medium Access Control (MAC) Control Element (MAC-CE) communications, or Downlink Control Information (DCI) communications; and Wherein, when selecting the cyclic shift index from the group of cyclic shift indices, the one or more processors are configured to: The cyclic shift index is selected from the group of cyclic shift indices based at least in part on the indication of the occ-index.

25. The UE of claim 21, wherein the cyclic shift index group is associated with a plurality of DMRS sequences, The plurality of DMRS sequences are based at least in part on corresponding π / 2 BPSK modulated computer-generated binary sequences.

26. The UE of claim 21, wherein the cyclic shift index group includes cyclic shift indexes 0, 2, 5, 10 or cyclic shift indexes 0, 2, 7, 10 for a multiplexing capacity of a PUCCH format 4 configuration equal to 4, or The cyclic shift index group includes cyclic shift index 0, 5 or cyclic shift index 0, 7 for a multiplexing capacity of PUCCH format 4 configuration equal to 2.

27. A non-transitory computer-readable medium storing one or more instructions for wireless communication, the one or more instructions comprising: One or more instructions that when executed by one or more processors of a user equipment (UE) cause the one or more processors to: cyclically shifting a demodulation reference signal (DMRS) sequence based at least in part on a cyclic shift index selected from a group of cyclic shift indices, wherein the DMRS sequence is modulated in the time domain, and wherein amplitudes of values ​​in the DMRS sequence are not flat across different tones, wherein a cyclic gap between cyclic shift indices included in the cyclic shift index group is at least 2 and not 6; and A DMRS corresponding to a shifted DMRS sequence with π / 2 binary phase shift keying (BPSK) modulation is transmitted on a physical uplink control channel (PUCCH).

28. The non-transitory computer readable medium of claim 27, wherein the one or more instructions that cause the one or more processors to transmit the DMRS cause the one or more processors to: transmitting the DMRS on the PUCCH in a resource block (RB), The DMRS is multiplexed in the RB with one or more other DMRSs transmitted from one or more other UEs.

29. The non-transitory computer readable medium of claim 27, wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to: The cyclic shift index is selected from the group of cyclic shift indices based at least in part on an orthogonal cover code index (occ-index) associated with the UE.

30. The non-transitory computer readable medium of claim 29, wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to: Receiving an indication of the occ-index in at least one of: Radio Resource Control (RRC) communications, Medium Access Control (MAC) Control Element (MAC-CE) communications, or Downlink Control Information (DCI) communications; and wherein the one or more instructions that cause the one or more processors to select the cyclic shift index from the group of cyclic shift indices cause the one or more processors to: The cyclic shift index is selected from the group of cyclic shift indices based at least in part on the indication of the occ-index.

31. An apparatus for wireless communication, comprising: means for cyclically shifting a demodulation reference signal (DMRS) sequence based at least in part on a cyclic shift index selected from a group of cyclic shift indices, wherein the DMRS sequence is modulated in the time domain, and wherein amplitudes of values ​​in the DMRS sequence are not flat across different tones, wherein the cyclic gap between the cyclic shift indices included in the cyclic shift index group is at least 2 and not 6; as well as Means for transmitting a DMRS corresponding to a shifted DMRS sequence with π / 2 binary phase shift keying (BPSK) modulation on a physical uplink control channel (PUCCH).

32. The apparatus of claim 31 , wherein the means for transmitting the DMRS comprises: means for transmitting the DMRS on the PUCCH in a resource block (RB), The DMRS is multiplexed in the RB with one or more other DMRSs transmitted from one or more other UEs.

33. The apparatus of claim 31, further comprising: means for selecting the cyclic shift index from the group of cyclic shift indices based at least in part on an orthogonal cover code index (occ-index) associated with the apparatus.

34. The apparatus of claim 33, further comprising: means for receiving an indication of the occ-index in at least one of: Radio Resource Control (RRC) communications, Medium Access Control (MAC) Control Element (MAC-CE) communications, or Downlink Control Information (DCI) communications; as well as The means for selecting the cyclic shift index from the cyclic shift index group comprises: means for selecting the cyclic shift index from the group of cyclic shift indices based at least in part on the indication of the occ-index.

35. The apparatus of claim 31 , wherein the group of cyclic shift indices is associated with a plurality of DMRS sequences, The plurality of DMRS sequences are based at least in part on corresponding π / 2 BPSK modulated computer-generated binary sequences.

36. The apparatus of claim 31 , wherein the group of cyclic shift indices comprises cyclic shift indices 0, 2, 5, 10 or cyclic shift indices 0, 2, 7, 10 for a multiplexing capacity of a PUCCH format 4 configuration equal to 4, or The cyclic shift index group includes cyclic shift index 0, 5 or cyclic shift index 0, 7 for a multiplexing capacity of PUCCH format 4 configuration equal to 2.

37. A user equipment (UE) for wireless communication, comprising: Memory; as well as one or more processors operatively coupled to the memory, the memory and the one or more processors being configured to: receiving an indication of a plurality of cyclic shift index groups, wherein each cyclic shift index group of the plurality of cyclic shift index groups is associated with one or more demodulation reference signal (DMRS) sequences, wherein the DMRS sequences are modulated in the time domain, and wherein amplitudes of values ​​in the DMRS sequences are not flat across different tones; cyclically shifting the DMRS sequence based at least in part on a cyclic shift index included in a group of cyclic shift indices associated with a DMRS sequence of the one or more DMRS sequences; and A DMRS corresponding to a shifted DMRS sequence with π / 2 binary phase shift keying (BPSK) modulation is transmitted on a physical uplink control channel (PUCCH).

38. The UE of claim 37, wherein the one or more DMRS sequences are based at least in part on corresponding π / 2 BPSK modulated computer-generated binary sequences.

39. The UE of claim 37, wherein when transmitting the DMRS, the one or more processors are to: transmitting the DMRS on the PUCCH in a resource block (RB), The DMRS is multiplexed in the RB with one or more other DMRSs transmitted from one or more other UEs.

40. The UE of claim 37, wherein the one or more processors are further configured to: The cyclic shift index is selected from the group of cyclic shift indices based at least in part on at least one of: an orthogonal cover code index (occ-index) associated with the UE, or A DMRS sequence index associated with the DMRS sequence.

41. The UE of claim 40, wherein the one or more processors are further configured to: Receiving an indication of the occ-index in at least one of: Radio Resource Control (RRC) communications, Medium Access Control (MAC) Control Element (MAC-CE) communications, or Downlink Control Information (DCI) communications; and Wherein, when selecting the cyclic shift index from the group of cyclic shift indices, the one or more processors are configured to: The cyclic shift index is selected from the group of cyclic shift indices based at least in part on the indication of the occ-index.

42. The UE of claim 37, wherein the one or more DMRS sequences are associated with corresponding DMRS sequence indexes; and wherein the one or more processors are further configured to: determining that the DMRS sequence is associated with the group of cyclic shift indices based at least in part on a DMRS sequence index associated with the DMRS sequence; and wherein when shifting the DMRS sequence based at least in part on the cyclic shift index included in the cyclic shift index group associated with the DMRS sequence, the one or more processors are configured to: Based at least in part on determining that the group of cyclic shift indices is associated with the DMRS sequence, the DMRS sequence is shifted at least in part based on the cyclic shift indices included in the group of cyclic shift indices.

43. A non-transitory computer-readable medium storing one or more instructions for wireless communication, the one or more instructions comprising: One or more instructions that when executed by one or more processors of a user equipment (UE) cause the one or more processors to: receiving an indication of a plurality of cyclic shift index groups, wherein each cyclic shift index group of the plurality of cyclic shift index groups is associated with one or more demodulation reference signal (DMRS) sequences, wherein the DMRS sequences are modulated in the time domain, and wherein amplitudes of values ​​in the DMRS sequences are not flat across different tones; cyclically shifting the DMRS sequence based at least in part on a cyclic shift index included in a group of cyclic shift indices associated with a DMRS sequence of the one or more DMRS sequences; and A DMRS corresponding to a shifted DMRS sequence with π / 2 binary phase shift keying (BPSK) modulation is transmitted on a physical uplink control channel (PUCCH).

44. The non-transitory computer readable medium of claim 43, wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to: The cyclic shift index is selected from the group of cyclic shift indices based at least in part on at least one of: an orthogonal cover code index (occ-index) associated with the UE, or A DMRS sequence index associated with the DMRS sequence.

45. The non-transitory computer readable medium of claim 44, wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to: Receiving an indication of the occ-index in at least one of: Radio Resource Control (RRC) communications, Medium Access Control (MAC) Control Element (MAC-CE) communications, or Downlink Control Information (DCI) communications; and wherein the one or more instructions that cause the one or more processors to select the cyclic shift index from the group of cyclic shift indices cause the one or more processors to: The cyclic shift index is selected from the group of cyclic shift indices based at least in part on the indication of the occ-index.

46. ​​The non-transitory computer-readable medium of claim 43, wherein the one or more DMRS sequences are associated with corresponding DMRS sequence indexes; and wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to: determining that the DMRS sequence is associated with the group of cyclic shift indices based at least in part on a DMRS sequence index associated with the DMRS sequence; and wherein the one or more instructions to shift the DMRS sequence based at least in part on the cyclic shift index included in the group of cyclic shift indices associated with the DMRS sequence cause the one or more processors to: Based at least in part on determining that the group of cyclic shift indices is associated with the DMRS sequence, the DMRS sequence is shifted at least in part based on the cyclic shift indices included in the group of cyclic shift indices.

47. An apparatus for wireless communication, comprising: means for receiving an indication of a plurality of groups of cyclic shift indices, wherein each cyclic shift index group of the plurality of cyclic shift index groups is associated with one or more demodulation reference signal (DMRS) sequences, wherein the DMRS sequences are modulated in the time domain, and wherein amplitudes of values ​​in the DMRS sequences are not flat across different tones; means for cyclically shifting the DMRS sequence based at least in part on a cyclic shift index included in a group of cyclic shift indices associated with a DMRS sequence of the one or more DMRS sequences; as well as Means for transmitting a DMRS corresponding to a shifted DMRS sequence with π / 2 binary phase shift keying (BPSK) modulation on a physical uplink control channel (PUCCH).

48. The apparatus of claim 47, wherein the one or more DMRS sequences are based at least in part on corresponding π / 2 BPSK modulated computer-generated binary sequences.

49. The apparatus of claim 47, wherein the means for transmitting the DMRS comprises: means for transmitting the DMRS on the PUCCH in a resource block (RB), The DMRS is multiplexed in the RB with one or more other DMRSs transmitted from one or more other UEs.

50. The apparatus of claim 47, further comprising: means for selecting the cyclic shift index from the group of cyclic shift indices based at least in part on at least one of: the orthogonal cover code index (occ-index) associated with the equipment, or A DMRS sequence index associated with the DMRS sequence.

51. The apparatus of claim 50, further comprising: Receiving an indication of the occ-index in at least one of: Radio Resource Control (RRC) communications, Medium Access Control (MAC) Control Element (MAC-CE) communications, or Downlink Control Information (DCI) communications; as well as The means for selecting the cyclic shift index from the cyclic shift index group comprises: means for selecting the cyclic shift index from the group of cyclic shift indices based at least in part on the indication of the occ-index.

52. The apparatus of claim 47, wherein the one or more DMRS sequences are associated with corresponding DMRS sequence indexes; as well as The equipment further comprises: means for determining that the DMRS sequence is associated with the group of cyclic shift indices based at least in part on a DMRS sequence index associated with the DMRS sequence; and Wherein the means for shifting the DMRS sequence based at least in part on the cyclic shift index included in the cyclic shift index group associated with the DMRS sequence comprises: Means for shifting the DMRS sequence based at least in part on the cyclic shift indices included in the group of cyclic shift indices based at least in part on determining that the group of cyclic shift indices is associated with the DMRS sequence.

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