KR20230117109A - Codebook for Distributed MIMO Transmission - Google Patents

Abstract

The present disclosure relates to a communication method and system that converges a 5th generation (5G) communication system supporting a higher data transmission rate than a 4th generation (4G) system using Internet of Things (IoT) technology. The present disclosure can be applied to intelligent services based on 5G communication technology and IoT related technologies such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety service. This disclosure relates to codebook-based channel state information (CSI) reporting for distributed MIMO transmission.

Description

Codebook for Distributed MIMO Transmission

This disclosure relates generally to wireless communication systems, and more specifically to CSI reporting based on codebooks for distributed MIMO transmission.

Efforts are being made to develop improved 5G or pre-5G communication systems to meet the growing demand for wireless data traffic after the commercialization of 4G communication systems. For this reason, the 5G or pre-5G communication system is also being called a "Beyond 4G Network" communication system or a "Post LTE System" communication system. In order to achieve a high data rate, the 5G communication system is considered to be implemented in a mmWave band (eg, 60 GHz band). In order to reduce the propagation loss of radio waves and increase the transmission distance, beamforming, huge MIMO (Multiple-Input Multiple-Output), FD-MIMO (Full Dimensional MIMO), and array antennas in 5G communication systems (array antenna), analog beam forming, and large scale antenna technologies are being discussed. In addition, in order to improve the network of the system, in the 5G communication system, advanced small cells, cloud radio access networks (cloud RAN), ultra-dense networks, and device-to-device communication (Device-to-Device (D2D) communication), wireless backhaul, moving network, cooperative communication, CoMP (Coordinated Multi-Point), reception-end interference cancellation) is being developed. In the 5G communication system, advanced coding modulation (Advanced Coding Modulation, ACM) methods such as FQAM (Hybrid FSK and QAM Modulation) and SWSC (Sliding Window Superposition Coding), advanced access technologies FBMC (Filter Bank Multi Carrier), NOMA (non -Orthogonal multiple access and sparse code multiple access (SCMA) are being developed.

The Internet, a human-centric network of connections in which humans create and consume information, is now evolving into the Internet of Things (IoT), in which distributed entities such as things exchange and process information without human intervention. IoE (Internet of Everything) technology, which combines IoT technology and Big Data processing technology through connection with a cloud server, is emerging. In order to implement IoT, technology elements such as sensing technology, wired/wireless communication and network infrastructure, service interface technology, and security technology are required, and recently, sensor networks for connection between objects, machine-to-machine (M2M) Machine) and MTC (Machine Type Communication) technologies are being studied. In the IoT environment, intelligent IT (Internet Technology) services that create new values in human life by collecting and analyzing data generated from connected objects can be provided. IoT is a smart home, smart building, smart city, smart car or connected car, smart grid, health care, smart home appliances, advanced medical service, etc. can be applied in the field.

Accordingly, various attempts have been made to apply the 5G communication system to the IoT network. For example, technologies such as sensor network, machine type communication (MTC), and machine-to-machine (M2M) are 5G communication technologies implemented by techniques such as beamforming, MIMO, and array antenna. will be. The application of the cloud radio access network (RAN) as the big data processing technology described above can be regarded as an example of convergence between 5G technology and IoT technology.

Understanding and correctly estimating the channel between a user equipment (UE) and a base station (BS) (eg, gNode B (gNB)) is critical to efficient and effective wireless communication. In order to correctly estimate the DL channel state, the gNB may transmit a reference signal, eg CSI-RS, to the UE for DL channel measurement, and the UE reports information about channel measurement, eg CSI, to the gNB ( feedback). Through such DL channel measurement, the gNB can select appropriate communication parameters to efficiently and effectively perform wireless data communication with the UE.

There is a need to design a codebook for a distributed MIMO antenna structure for efficient and effective wireless communication.

Embodiments of the present disclosure provide a method and apparatus for enabling channel state information (CSI) reporting based on a codebook for distributed MIMO transmission in a wireless communication system.

In one embodiment, a UE for CSI reporting in a wireless communication system is provided. The UE includes a transceiver configured to receive information about channel state information (CSI) reporting, the information being > 1 and RRH Including, where, = number of remote radio heads (RRH), RRH Is Contains a group of channel state information reference signal (CSIRS) antenna ports, r = 1,..., am. The UE further includes a processor operably coupled to the transceiver. Based on the information, the processor select the strongest RRH from the RRHs; It is configured to determine a CSI report including an indicator indicating the strongest RRH. The transceiver is further configured to transmit a CSI report including an indicator indicating the strongest RRH.

In another embodiment, a BS is provided in a wireless communication system. The BS includes a processor configured to generate information about channel state information (CSI) reporting, and the information can be > 1 and RRH Including, where, = number of remote radio heads (RRH), RRH Is Contains a group of channel state information reference signal (CSIRS) antenna ports, r = 1,..., am. The BS further includes a transceiver operably coupled to the processor. the transceiver transmits information; set to receive CSI reports, and the CSI reports An indicator indicating the strongest RRH selected from the RRHs is included.

In another embodiment, a method of operating a UE is provided. This method is a step of receiving information about a channel state information (CSI) report, wherein the information is > 1 and RRH Including, = number of remote radio heads (RRH), RRH Is Contains a group of channel state information reference signal (CSIRS) antenna ports, r = 1,..., In, receiving; selecting the strongest RRH from the RRHs; determining a CSI report including an indicator indicating the strongest RRH; and transmitting a CSI report including an indicator indicating the strongest RRH.

Other technical features may be readily apparent to those skilled in the art from the following drawings, description and claims.

According to the present disclosure, several codebook design alternatives are provided for a D-MIMO antenna structure for efficient and effective wireless communication.

For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in connection with the accompanying drawings in which like reference numerals indicate like parts.
1 illustrates an exemplary wireless network in accordance with an embodiment of the present disclosure.
2 illustrates an exemplary gNB according to an embodiment of the present disclosure.
3 illustrates an exemplary UE according to an embodiment of the present disclosure.
4A shows a high level diagram of an orthogonal frequency division multiple access transmission path in accordance with an embodiment of the present disclosure.
4B shows a high level diagram of an orthogonal frequency division multiple access receive path in accordance with an embodiment of the present disclosure.
5 shows a transmitter block diagram for a PDSCH in a subframe according to an embodiment of the present disclosure.
6 shows a receiver block diagram for a PDSCH in a subframe according to an embodiment of the present disclosure.
7 shows a transmitter block diagram for PUSCH in a subframe according to an embodiment of the present disclosure.
8 shows a receiver block diagram for PUSCH in a subframe according to an embodiment of the present disclosure.
9 illustrates an exemplary antenna block or array forming a beam in accordance with an embodiment of the present disclosure.
10 illustrates an exemplary Distributed MIMO (D-MIMO) system according to an embodiment of the present disclosure.
11 shows an exemplary antenna port layout according to an embodiment of the present disclosure.
12 illustrates an example of Type I single panel (SP) and Type I multi-panel (MP) codebook-based MIMO transmission according to an embodiment of the present disclosure.
13 illustrates an exemplary D-MIMO where each RRH has a single antenna panel according to an embodiment of the present disclosure.
14 illustrates an example D-MIMO where each RRH has multiple antenna panels according to an embodiment of the present disclosure.
15 illustrates an exemplary D-MIMO where each RRH may have a single antenna panel or multiple antenna panels according to an embodiment of the present disclosure.
16 shows a flowchart of a method of operating a UE according to an embodiment of the present disclosure.
17 shows a flowchart of a method of operating a BS according to an embodiment of the present disclosure.

Before embarking on the detailed description below, it may be beneficial to define certain words and phrases used throughout this patent document. The term "couple" and its derivatives refers to any direct or indirect communication between two or more elements, whether or not the two or more elements are in physical contact with each other. The terms “transmit,” “receive,” and “communicate,” as well as their derivatives, include both direct and indirect communications. The terms "include" and "comprise", as well as derivatives thereof, mean inclusion without limitation. The term “or” is inclusive and means and/or. The term “associated with,” as well as its derivatives, includes “includes,” “included within,” “interconnects with,” "contain", "be contained within", "connect to or with", "couple to or with" to or with", "be communicable with", "cooperate with", "interleave", "juxtapose", "be proximate to", "be bound to or with", "have", "have a property of", "~ To or, have a relationship to or with", etc. The term "controller" means any device, system, or portion thereof that controls at least one operation. The controller may be implemented in hardware or a combination of hardware and software and/or firmware. Functionality associated with any particular control unit may be centralized or distributed, either locally or remotely. The phrase "at least one of", when used with a list of items, means that different combinations of one or more of the listed items may be used, and only one item may be required within the list. For example, “at least one of A, B, and C” includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A and B and C.

Moreover, various functions described below may be implemented or supported by one or more computer programs, and each computer program is formed from computer readable program code and is stored in a computer readable medium. ) is implemented in The terms "application" and "program" mean one or more computer programs, software components, sets of instructions, procedures, functions, or objects adapted for implementation in appropriate computer readable program code. ), class, instance, related data, or part thereof. The phrase "computer readable program code" includes any type of computer code, including source code, object code and executable code. The phrase “computer readable medium” includes read only memory (ROM), random access memory (RAM), hard disk drive, compact disc (CD), digital video disc DVD), or any other type of memory that can be accessed by a computer. A “non-transitory” computer readable medium excludes wired, wireless, optical or other communication links that transmit transitory electrical or other signals. Non-transitory computer-readable media include media on which data can be permanently stored and media on which data can be stored and later overwritten, such as a rewritable optical disk or a removable memory device.

Definitions for other specific words and phrases are provided throughout this patent document. Skilled artisans should understand that in most, if not cases, these definitions apply to the preceding and succeeding uses of these defined words and phrases.

1-17, discussed below, and the various embodiments used to explain the principles of the present disclosure in this patent document are for illustrative purposes only and should not be construed as limiting the scope of the present disclosure in any way. Skilled artisans can understand that the principles of this disclosure can be implemented in any system or device suitably arranged.

The following documents and standards descriptions are incorporated by reference into this disclosure as if fully set forth herein: 3GPP TS 36.211 v16.6.0, “E-UTRA, Physical channels and modulation” (herein “REF 1”); 3GPP TS 36.212 v16.6.0, "E-UTRA, Multiplexing and Channel coding" (herein "REF 2"); 3GPP TS 36.213 v16.6.0, "E-UTRA, Physical Layer Procedures" (herein "REF 3"); 3GPP TS 36.321 v16.6.0, "E-UTRA, Medium Access Control (MAC) protocol specification" (herein "REF 4"); 3GPP TS 36.331 v16.6.0, "E-UTRA, Radio Resource Control (RRC) protocol specification" (herein "REF 5"); 3GPP TR 22.891 v14.2.0 (herein "REF 6"); 3GPP TS 38.212 v16.6.0, “E-UTRA, NR, Multiplexing and channel coding” (herein “REF 7”); and 3GPP TS 38.214 v16.6.0, "E-UTRA, NR, Physical layer procedures for data" (herein "REF 8").

Aspects, features, and advantages of the present disclosure are apparent from the following detailed description, merely illustrating a number of specific embodiments and implementations including the best mode contemplated for carrying out the present disclosure. The present disclosure is also capable of other and different embodiments, and its several details may be modified in various obvious respects, all without departing from the spirit and scope of the present disclosure. Accordingly, the drawings and description are to be regarded as illustrative in nature and not restrictive. The disclosure is illustrated by way of example and not limitation in the accompanying drawings.

In the following, for brevity, both FDD and TDD are considered as duplex methods for DL and UL signaling.

Although the following exemplary descriptions and embodiments assume orthogonal frequency division multiplexing (OFDM) or orthogonal frequency division multiple access (OFDMA), the present disclosure does not address other OFDM-based transmission waveforms or F- It can be extended to multiple access schemes such as filtered OFDM (OFDM).

In order to meet the demand for wireless data traffic that has increased since the commercialization of the 4G communication system and to enable various vertical applications, a 5G/NR communication system has been developed and is currently being deployed. 5G/NR communication systems are implemented in higher frequency (mmWave) bands, e.g., 28 GHz or 60 GHz bands, to achieve higher data rates, or lower frequencies, such as 6 GHz, to enable robust coverage and mobility support. considered to be implemented in band. In order to reduce the propagation loss of radio waves and increase the transmission distance, beamforming, huge multiple-input multiple-output (MIMO), full dimensional MIMO (FD-MIMO), array antenna, analog beamforming and Large-scale antenna technology is being discussed.

In addition, in the 5G/NR communication system, advanced small cell, cloud radio access network (RAN), ultra-dense network, device-to-device (D2D) communication, wireless backhaul, mobile network, cooperative communication, CoMP (coordinated multi-point), reception However, development for system network improvement is being made based on interference cancellation.

The discussion of 5G systems and their associated frequency bands is for reference only as certain embodiments of this disclosure may be implemented in 5G systems. However, the present disclosure is not limited to 5G systems or frequency bands associated therewith, and embodiments of the present disclosure may be utilized in relation to any frequency band. For example, aspects of the present disclosure may also be applied to the deployment of 5G communication systems, 6G or later releases that may use the Terahertz (THz) band.

1 to 4B below describe various embodiments implemented using orthogonal frequency division multiplexing (OFDM) or orthogonal frequency division multiple access (OFDMA) communication technology in a wireless communication system. The description of FIGS. 1-3 does not imply physical or structural limitations on the manner in which different embodiments may be implemented. Different embodiments of the present disclosure may be implemented in any suitably arranged communications system. The present disclosure includes several components that can be used together or in combination with one another or can operate in a stand-alone manner.

1 illustrates an exemplary wireless network in accordance with the present disclosure. The embodiment of the wireless network shown in FIG. 1 is for illustration only. Other embodiments of wireless network 100 may be used without departing from the scope of the present disclosure.

As shown in FIG. 1 , the wireless network includes gNB 101 , gNB 102 and gNB 103 . gNB 101 communicates with gNB 102 and gNB 103 . The gNB 101 also communicates with at least one network 130, such as the Internet, a proprietary Internet Protocol (IP) network, or another data network.

The gNB 102 provides wireless broadband access to the network 130 for a first plurality of user equipments (UEs) within a coverage area 120 of the gNB 102 . The first plurality of UEs includes a UE 111 that may be located in a small business (SB); UE 112, which may be located in an enterprise (E); UE 113, which may be located in a WiFi hotspot (HS); UE 114, which may be located at a first residence (R); UE 115, which may be located in the second residence (R); and UE 116, which may be a mobile device (M) such as a cell phone, wireless laptop, wireless PDA, or the like. gNB 103 provides wireless broadband access to network 130 for a second plurality of UEs within coverage area 125 of gNB 103 . The second plurality of UEs includes UE 115 and UE 116 . In some embodiments, one or more of the gNBs 101 - 103 may communicate with each other and with the UEs 111 - 116 using 5G, LTE, LTE-A, WiMAX, WiFi or other wireless communication technologies.

Depending on the type of network, the term “base station” or “BS” may refer to a transmit point (TP), a transmit-receive point (TRP), an enhanced base station (eNodeB or eNB), or a 5G base station. Any component (or collection of components). The base station supports one or more wireless communication protocols, for example, 5G 3GPP new radio interface/access (NR), long term evolution (LTE), LTE-advanced (LTE-A), high speed packet access packet access, HSPA), Wi-Fi 802.11a/b/g/n/ac, etc., may provide wireless access. For convenience, the terms “BS” and “TRP” are used in this patent document to denote a network infrastructure component that provides wireless access to remote terminals. Also, depending on the type of network, the term "user equipment" or "UE" can be used to refer to "mobile station", "subscriber station", "remote terminal", "wireless terminal", "receive point" point)” or “user device”. For convenience, the terms "user device" and "UE" are used in this patent document to indicate whether a UE is a mobile device (such as a mobile phone or smart phone) or generic (such as a desktop computer or vending machine). Used to refer to a remote wireless device that wirelessly accesses a BS, whether considered a stationary device.

Dotted lines show the approximate extent of coverage areas 120 and 125, which are drawn nearly circular for illustration and explanation only. It is clear that coverage areas associated with a gNB, such as coverage areas 120 and 125, may have different shapes, including irregular shapes, depending on the configuration of the gNB and changes in the wireless environment related to natural and man-made obstructions. It should be understood.

As described in more detail below, one or more of the UEs 111 - 116 may receive information regarding channel state information (CSI) reporting - this information may be > 1 and RRH Including, = number of remote radio heads (RRH), RRH Is Contains a group of channel state information reference signal (CSIRS) antenna ports, r = 1,..., Lim - receives; select the strongest RRH from the RRHs; determine a CSI report containing an indicator representing the strongest RRH; Circuitry, programming, or combination thereof for transmitting a CSI report including an indicator indicating the strongest RRH. One or more of the gNBs 101-103 may report channel state information (CSI) information - this information may be > 1 and RRH Including, = number of remote radio heads (RRH), RRH Is Contains a group of channel state information reference signal (CSIRS) antenna ports, r = 1,..., Lim - generates; send information; CSI Reporting - CSI reporting is and an indicator indicating the strongest RRH selected from the RRHs.

Although FIG. 1 illustrates one example of a wireless network 100, various changes to FIG. 1 may be made. For example, wireless network 100 may include any number of gNBs and any number of UEs in any suitable arrangement. In addition, gNB 101 may communicate directly with any number of UEs and may provide wireless broadband access to network 130 to these UEs. Similarly, each gNB 102 - 103 can communicate directly with network 130 and provide UEs with direct wireless broadband access to the network. Additionally, gNBs 101 , 102 and/or 103 may provide access to other or additional external networks, such as external telephone networks or other types of data networks.

2 illustrates an example gNB 102 according to an embodiment of the present disclosure. The embodiment of gNB 102 shown in FIG. 2 is for illustration only, and gNBs 101 and 103 in FIG. 1 may have the same or similar configuration. However, gNBs have a variety of configurations, and FIG. 2 does not limit the scope of this disclosure to any particular implementation of gNBs.

As shown in FIG. 2, the gNB 102 includes multiple antennas 205a-205n, multiple RF transceivers 210a-210n, transmit (TX) processing circuitry 215, and receive (RX) processing circuitry (220). The gNB 102 also includes a control/processor 225 , memory 230 and a backhaul or network interface 235 .

RF transceivers 210a-210n receive incoming RF signals, such as signals transmitted by UEs in network 100, from antennas 205a-205n. The RF transceivers 210a-210n down-convert the incoming RF signal to produce an IF or baseband signal. The IF or baseband signal is sent to RX processing circuitry 220 which generates a processed baseband signal by filtering, decoding and/or digitizing the baseband or IF signal. RX processing circuitry 220 transmits the processed baseband signal to control/processor 225 for further processing.

TX processing circuitry 215 receives analog or digital data (such as voice data, web data, e-mail or interactive video game data) from control/processor 225. TX processing circuitry 215 encodes, multiplexes, and/or digitizes outgoing baseband data to generate a processed baseband or IF signal. The RF transceivers 210a-210n receive the outgoing processed baseband or IF signals from the TX processing circuitry 215 and up-convert the baseband or IF signals to RF signals that are transmitted via the antennas 205a-205n.

The controller/processor 225 may include one or more processors or other processing devices that control the overall operation of the gNB 102 . For example, the controller/processor 225 receives the UL channel signal and transmits the DL channel signal by the RF transceivers 210a to 210n, the RX processing circuit 220 and the TX processing circuit 215 according to well-known principles. can control. Controller/processor 225 may also support additional functions, such as more advanced wireless communication functions.

For example, the controller/processor 225 performs a beamforming or directional routing operation in which outgoing signals from multiple antennas 205a-205n are weighted differently to effectively steer the outgoing signals in a desired direction. ) can be supported. Any of a variety of other functions may be supported in gNB 102 by control/processor 225 .

Controller/processor 225 may also execute programs and other processes resident in memory 230, such as an OS. Controller/processor 225 may move data into and out of memory 230 as required by an executing process.

Control/processor 225 is also coupled to backhaul or network interface 235 . Backhaul or network interface 235 allows gNB 102 to communicate with other devices or systems over a backhaul connection or network. Interface 235 may support communication over any suitable wired or wireless connection. For example, when gNB 102 is implemented as part of a cellular communication system (such as supporting 5G, LTE, or LTE-A), interface 235 may allow gNB 102 to be wired or It allows communication with other gNBs over a wireless backhaul connection. When gNB 102 is implemented as an access point, interface 235 allows gNB 102 to communicate with a wired or wireless local area network or a larger network (such as the Internet) over a wired or wireless connection. allow you to do Interface 235 includes any suitable structure that supports communication over a wired or wireless connection, such as an Ethernet or RF transceiver.

Memory 230 is coupled to control/processor 225 . A portion of memory 230 may include RAM, and another portion of memory 230 may include flash memory or other ROM.

Although FIG. 2 shows one example of gNB 102 , various changes to FIG. 2 may be made. For example, gNB 102 may include any number of each component shown in FIG. 2 . As a specific example, an access point may include multiple interfaces 235, and control/processor 225 may support a routing function to route data between different network addresses. As another particular example, while shown as including a single instance of TX processing circuitry 215 and a single instance of RX processing circuitry 220, gNB 102 may (such as one per RF transceiver) each Can contain multiple instances. In addition, various components of FIG. 2 may be combined, further subdivided, or omitted, and additional components may be added according to specific needs.

3 illustrates an exemplary UE 116 according to an embodiment of the present disclosure. The embodiment of UE 116 shown in FIG. 3 is for illustration only, and UEs 111-115 in FIG. 1 may have the same or similar configuration. However, UEs have a variety of configurations, and FIG. 3 does not limit the scope of this disclosure to any particular implementation of a UE.

As shown in FIG. 3, UE 116 includes an antenna 305, a radio frequency (RF) transceiver 310, TX processing circuitry 315, a microphone 320, and receive (RX) processing circuitry ( 325). The UE 116 also includes a speaker 330, a processor 340, an input/output (I/O) interface (IF) 345, a touchscreen 350, a display 355 and A memory 360 is included. The memory 360 includes an operating system (OS) 361 and one or more applications 362 .

RF transceiver 310 receives, from antenna 305 , incoming RF signals transmitted by gNBs in network 100 . The RF transceiver 310 downconverts the incoming RF signal to generate an intermediate frequency (IF) or baseband signal. The IF or baseband signal is sent to RX processing circuitry 325 which generates a processed baseband signal by filtering, decoding and/or digitizing the baseband or IF signal. RX processing circuit 325 sends the processed baseband signal to speaker 330 (such as for voice data) or processor 340 (such as for web browsing data) for further processing. transmit

TX processing circuitry 315 receives analog or digital voice data from microphone 320 or other outgoing baseband data (such as web data, e-mail or interactive video game data) from processor 340. TX processing circuitry 315 encodes, multiplexes, and/or digitizes the outgoing baseband data to generate a processed baseband or IF signal. The RF transceiver 310 receives the processed baseband or IF signal outgoing from the TX processing circuitry 315 and upconverts the baseband or IF signal to an RF signal transmitted via the antenna 305.

Processor 340 may include one or more processors or other processing units, and may execute OS 361 stored in memory 360 to control overall operation of UE 116 . For example, processor 340 may control reception of forward channel signals and transmission of reverse channel signals by RF transceiver 310, RX processing circuitry 325, and TX processing circuitry 315 according to well-known principles. there is. In some embodiments, processor 340 includes at least one microprocessor or microcontroller.

Processor 340 also provides information regarding channel state information (CSI) reporting - this information may be > 1 and RRH Including, = number of remote radio heads (RRH), RRH Is Contains a group of channel state information reference signal (CSIRS) antenna ports, r = 1,..., Lim - receives; select the strongest RRH from the RRHs; determine a CSI report containing an indicator representing the strongest RRH; Other processes and programs residing in memory 360 may be executed, such as a process for sending a CSI report containing an indicator indicating the strongest RRH. Processor 340 may move data into and out of memory 360 as required by an executing process. In some embodiments, processor 340 is configured to execute application 362 based on OS 361 or in response to signals received from the gNB or operator. Processor 340 is also coupled to I/O interface 345 which provides UE 116 with the ability to connect to other devices such as laptop computers and handheld computers. I/O interface 345 is a communication path between this accessory and processor 340 .

Processor 340 is also coupled to touchscreen 350 and display 355 . An operator of UE 116 may input data into UE 116 using touch screen 350 . Display 355 may be a liquid crystal display, light emitting diode display, or other display capable of rendering text and/or at least limited graphics, such as from a web site. can be

Memory 360 is coupled to processor 340 . Part of memory 360 may include random access memory (RAM), and another part of memory 360 may include flash memory or other read-only memory (ROM). there is.

Although FIG. 3 shows one example of UE 116 , various changes to FIG. 3 may be made. For example, various components of FIG. 3 may be combined, further subdivided, or omitted, and additional components may be added according to specific needs. As a specific example, processor 340 may be divided into multiple processors, such as one or more central processing units (CPUs) and one or more graphics processing units (GPUs). 3 also shows UE 116 configured as a mobile or smart phone, the UE may be configured to operate as another type of mobile or stationary device.

4A is a high level diagram of transmit path circuitry. For example, the transmit path circuitry may be used for orthogonal frequency division multiple access (OFDMA) communications. Figure 4b is a high level diagram of the receive path circuitry. For example, receive path circuitry 450 may be used for OFDMA communications. 4A and 4B, for downlink communication, the transmit path circuitry may be implemented in a base station (gNB) 102 or a relay station, and the receive path circuitry may be implemented in a user equipment (e.g., in FIG. 1). may be implemented on the user device 116 . In another example, for uplink communications, receive path circuitry 450 can be implemented in a base station (eg, gNB 102 in FIG. 1 ) or a relay station, and transmit path circuitry can be implemented in a user device (eg, gNB 102 in FIG. It may be implemented in the user device 116 of FIG. 1 .

The transmit path circuitry includes a channel coding and modulation block 405, a serial-to-parallel (S-to-P) block 410, and a size N inverse fast Fourier transform (Inverse Fast Fourier Transform). Fourier Transform (IFFT) block 415, parallel-to-serial (P-to-S) block 420, add cyclic prefix block 425 and up converter -converter; UC) (430). Receive path circuitry 450 includes a down-converter (DC) 455, a remove cyclic prefix block 460, a serial-to-parallel (S-to-P) block 465, Includes size N fast Fourier transform (FFT) block 470, parallel-to-serial (P-to-S) block 475, and channel decoding and demodulation block 480 do.

At least some of the components in FIGS. 4A (400) and 4B (450) may be implemented by software, but other components may be implemented by configurable hardware or a mixture of software and configurable hardware. In particular, it is noted that the FFT blocks and IFFT blocks described in this disclosure document can be implemented as configurable software algorithms, where the value of size N can be modified depending on the implementation.

Further, although the present disclosure relates to embodiments of implementing fast Fourier transform and inverse fast Fourier transform, this is for illustration only and should not be construed as limiting the scope of the present disclosure. In an alternative embodiment of the present disclosure, the fast Fourier transform function and the inverse fast Fourier transform function can be easily replaced with a discrete Fourier transform (DFT) function and an inverse discrete Fourier transform (IDFT) function, respectively. It can be understood that For the DFT and IDFT functions, the value of the N variable can be any integer (i.e., 1, 4, 3, 4, etc.), whereas for the FFT and IFFT functions, the value of the N variable can be any power of two. It can be understood that it can be an integer (ie 1, 2, 4, 8, 16, etc.).

In transmit path circuitry 400, channel coding and modulation block 405 receives a set of information bits, applies coding (e.g., LDPC coding), and converts a series of frequency domain modulation symbols ( An input bit is modulated to generate a frequency-domain modulation symbol (eg, quadrature phase shift keying (QPSK) or quadrature amplitude modulation (QAM)). A serial-to-parallel block 410 is serial-to-parallel to generate N parallel symbol streams where N is the IFFT/FFT size used in BS 102 and UE 116. The serial modulated symbol is converted to parallel data (i.e., de-multiplexed). Size N IFFT block 415 then performs IFFT operations on the N parallel symbol streams to produce a time-domain output signal. Parallel to serial block 420 converts the parallel time-domain output symbol from size N IFFT block 415 to produce a serial time-domain signal. (i.e. multiplex). A cyclic prefix addition block 425 then inserts a cyclic prefix into the time-domain signal. Finally, upconverter 430 modulates (eg, upconverts) the output of cyclic prefix addition block 425 to an RF frequency for transmission over the wireless channel. The signal may also be filtered at baseband prior to conversion to the RF frequency.

The transmitted RF signal reaches the UE 116 after passing through the radio channel, and a reverse operation with that of the gNB 102 is performed. Downconverter 455 downconverts the received signal to a baseband frequency, and cyclic prefix removal block 460 removes the cyclic prefix to produce a serial time-domain baseband signal. The serial-to-parallel block 465 converts the time-domain baseband signal to a parallel time-domain signal. Size N FFT block 470 then performs the FFT algorithm to generate N parallel frequency domain signals. Parallel to serial block 475 converts the parallel frequency domain signal into a series of modulated data symbols. Channel decoding and demodulation block 480 demodulates and decodes the modulated symbols to recover the original input data stream.

Each of the gNBs 101-103 may implement a transmit path similar to transmitting to UEs 111-116 on the downlink, and may implement a receive path similar to receiving from UEs 111-116 on the uplink. can Similarly, each of the UEs 111-116 may implement a transmit path corresponding to the architecture for transmitting to the gNBs 101-103 on the uplink and receiving from the gNBs 101-103 on the downlink. It is possible to implement a receive path corresponding to the architecture for

The communication system includes a downlink (DL) that carries signals from a transmitting point such as a base station (BS) or NodeB to a user equipment (UE) and an uplink (UL) that carries signals from the UE to a receiving point such as a NodeB. . A UE, also commonly referred to as a terminal or mobile station, may be stationary or mobile, and may be a cellular phone, personal computer device or automated device. An eNodeB, typically a stationary station, may also be referred to as an access point or other equivalent term. For LTE systems, a NodeB is often referred to as an eNodeB.

In a communication system such as an LTE system, a DL signal includes a data signal carrying information content, a control signal carrying DL control information (DCI), and a reference signal (RS), also known as a pilot signal. can do. The eNodeB transmits data information through a physical DL shared channel (PDSCH). The eNodeB transmits DCI through a physical DL control channel (PDCCH) or Enhanced PDCCH (EPDCCH).

The eNodeB transmits acknowledgment information in response to transmission of a data transport block (TB) from the UE on a physical hybrid ARQ indicator channel (PHICH). The eNodeB transmits one or more of a number of RS types including UE-common RS (CRS), channel state information RS (CSI-RS) or demodulation RS (DMRS). The CRS is transmitted over the DL system bandwidth (BW) and can be used by the UE to obtain a channel estimate to demodulate data or control information or to perform measurements. To reduce CRS overhead, an eNodeB may transmit CSI-RS with a smaller density in time and/or frequency domain than CRS. DMRS can be transmitted only in the BW of each PDSCH or EPDCCH, and the UE can use DMRS to demodulate data or control information in PDRSCH or EPDCCH, respectively. A transmission time interval for a DL channel is referred to as a subframe and may have a duration of eg 1 millisecond.

DL signaling also includes the transmission of logical channels carrying system control information. BCCH is mapped to a transport channel referred to as a broadcast channel (BCH) when the BCCH carries a master information block (MIB) or a DL shared channel when the BCCH carries a system information block (SIB). , DL-SCH). Most of the system information is contained in different SIBs transmitted using DL-SCH. The presence of system information on the DL-SCH in a subframe may be indicated by transmission of a corresponding PDCCH carrying a codeword with a cyclic redundancy check (CRC) scrambled with a special system information RNTI (SI-RNTI). Alternatively, scheduling information for SIB transmission may be provided in the previous SIB, and scheduling information for the first SIB (SIB-1) may be provided by the MIB.

DL resource allocation is performed in units of subframes and groups of physical resource blocks (PRBs). The transmission BW includes frequency resource units referred to as resource blocks (RBs). Each RB is It includes resource elements (REs) such as subcarriers or 12 REs. A unit of one RB spanning one subframe is referred to as a PRB. The UE has a total number of PDSCH transmission BWs. for RE RBs may be allocated.

The UL signal may include a data signal carrying data information, a control signal carrying UL control information (UCI), and a UL RS. UL RS includes DMRS and Sounding RS (SRS). The UE transmits DMRS only in the BW of each PUSCH or PUCCH. An eNodeB can demodulate a data signal or a UCI signal using DMRS. The UE transmits SRS to provide UL CSI to the eNodeB. The UE transmits data information or UCI on each Physical UL Shared Channel (PUSCH) or Physical UL Control Channel (PUCCH). If the UE needs to transmit data information and UCI in the same UL subframe, the UE can multiplex both to PUSCH. UCI is HARQ-ACK (Hybrid Automatic Repeat request acknowledgment) information indicating the absence of correct (ACK) or incorrect (NACK) detection or PDCCH detection (DTX) for data TB in PDSCH, UE A scheduling request (SR) indicating whether there is data in the buffer of, a rank indicator (RI), and channel state information (CSI) that allows the eNodeB to perform link adaptation for PDSCH transmission to the UE include HARQ-ACK information is also transmitted by the UE in response to detection of the PDCCH/EPDCCH indicating release of the semi-persistently scheduled PDSCH.

A UL subframe includes two slots. Each slot is for transmitting data information, UCI, DMRS or SRS. contains symbols. The frequency resource unit of UL system BW is RB. UE is the total for transmit BW for RE RB is allocated. For PUCCH, am. The last subframe symbol may be used to multiplex SRS transmissions from one or more UEs. The number of subframe symbols available for data/UCI/DMRS transmission is , where the last subframe symbol is used to transmit the SRS, and, otherwise, am.

5 shows a transmitter block diagram 500 for a PDSCH in a subframe according to an embodiment of the present disclosure. The embodiment of transmitter block diagram 500 shown in FIG. 5 is for illustration only. One or more components shown in FIG. 5 may be implemented in special circuitry configured to perform the mentioned functions, or one or more components may be implemented by one or more processors executing instructions to perform the mentioned functions. . 5 does not limit the scope of the present disclosure to any particular implementation of transmitter block diagram 500 .

As shown in FIG. 5, information bits 510 are encoded by an encoder 520, such as a turbo encoder, and modulated by a modulator 530 using, for example, quadrature phase shift keying (QPSK) modulation. The serial-to-parallel (S/P) converter 540 generates M modulation symbols provided subsequent to the mapper 550 to be mapped to the RE selected by the transmit BW selection unit 555 for the assigned PDSCH transmit BW; , unit 560 applies an Inverse fast Fourier transform (IFFT), the output is then serialized by a parallel-to-serial (P/S) converter 570 to produce a time-domain signal, filtering is Applied by (580), the signal is transmitted (590). Additional functions such as data scrambling, cyclic prefix insertion, time windowing, interleaving, etc. are well known in the art and are not shown for brevity.

6 shows a receiver block diagram 600 for a PDSCH in a subframe according to an embodiment of the present disclosure. The embodiment of diagram 600 shown in FIG. 6 is for illustration only. One or more components shown in FIG. 6 may be implemented in special circuitry set up to perform the mentioned functions, or one or more components may be implemented by one or more processors executing instructions to perform the mentioned functions. . 6 does not limit the scope of the disclosure to any particular implementation of diagram 600 .

As shown in FIG. 6, the received signal 610 is filtered by filter 620, the RE 630 for the assigned receive BW is selected by BW selector 635, and unit 640 A fast Fourier transform (FFT) is applied, and the output is serialized by parallel-to-serial converter 650. Subsequently, demodulator 660 coherently demodulates the data symbols by applying channel estimates obtained from DMRS or CRS (not shown), and decoder 670, such as a turbo decoder, estimates the information data bits 680. Decode the demodulated data to provide Additional functions such as time windowing, cyclic prefix removal, de-scrambling, channel estimation and de-interleaving are not shown for brevity.

7 shows a transmitter block diagram 700 for PUSCH in a subframe according to an embodiment of the present disclosure. The embodiment of block diagram 700 shown in FIG. 7 is for illustration only. One or more components shown in FIG. 7 may be implemented in special circuitry configured to perform the mentioned functions, or one or more components may be implemented by one or more processors executing instructions to perform the mentioned functions. . 7 does not limit the scope of the disclosure to any particular implementation of block diagram 700 .

As shown in FIG. 7 , information data bits 710 are encoded by an encoder 720 , such as a turbo encoder, and modulated by a modulator 730 . A discrete Fourier transform (DFT) unit 740 applies the DFT on the modulated data bits, and an RE 750 corresponding to the assigned PUSCH transmission BW is selected by a transmission BW selection unit 755 , unit 760 applies the IFFT, and after cyclic prefix insertion (not shown), filtering is applied by filter 770 and the signal is transmitted (780).

8 shows a receiver block diagram 800 for PUSCH in a subframe according to an embodiment of the present disclosure. The embodiment of block diagram 800 shown in FIG. 8 is for illustration only. One or more components shown in FIG. 8 may be implemented in special circuitry set up to perform the mentioned functions, or one or more components may be implemented by one or more processors executing instructions to perform the mentioned functions. . 8 does not limit the scope of the disclosure to any particular implementation of block diagram 800 .

As shown in FIG. 8 , received signal 810 is filtered by filter 820 . Then, after the cyclic prefix is removed (not shown), unit 830 applies FFT, and the RE 840 corresponding to the assigned PUSCH receive BW is selected by receive BW selector 845; Unit 850 applies an inverse DFT (IDFT), demodulator 860 coherently demodulates the data symbols by applying a channel estimate obtained from DMRS (not shown), and turbo A decoder (870), such as a decoder, decodes the demodulated data to provide an estimate of information data bits (880).

In next-generation cellular systems, various use cases beyond the capabilities of LTE systems are envisioned. A system capable of operating below 6 GHz and above 6 GHz (eg, in the mmWave domain), referred to as 5G or fifth-generation cellular systems, becomes one of the requirements. In 3GPP TR 22.891, 74 5G use cases have been identified and described; These use cases can be roughly classified into three different groups. The first group is called "enhanced mobile broadband (eMBB)" and targets high data rate services with less stringent latency and reliability requirements. The second group is called "ultra-reliable and low latency (URLL)", which targets applications with less stringent data rate requirements but less tolerance for latency. A third group is called “massive MTC (mMTC)”, which targets connecting a large number of low-power devices, such as 1 million per km ² , where reliability, data rate and latency requirements are less stringent.

9 shows an exemplary antenna block or array 900 according to an embodiment of the present disclosure. The embodiment of the antenna block or array 900 shown in FIG. 9 is for illustration only. 9 does not limit the scope of the present disclosure to any particular implementation of an antenna block or array 900.

For the mmWave band, although the number of antenna elements may be higher for a given form factor, the number of CSI-RS ports that may correspond to the number of digitally precoded ports is as shown in FIG. As such, they tend to be limited by hardware constraints (eg, being able to install a large number of ADC/DACs at mmWave frequencies). In this case, one CSI-RS port is mapped to a large number of antenna elements that can be controlled by a bank of analog phase shifters 901. Then, one CSI-RS port may correspond to one sub-array generating a narrow analog beam through analog beamforming 905 . This analog beam can be set to sweep over a wider range of angles 920 by changing the phase shifter bank across symbols or subframes. The number of subarrays (equal to the number of RF chains) is equal to the number of CSI-RS ports N _CSI-PORT . The digital beamforming unit 910 further increases the precoding gain by performing a linear combination over the N _CSI-PORT analog beams. Analog beams are wideband (and therefore not frequency selective), whereas digital precoding can vary across frequency subbands or resource blocks.

Efficient design of CSI-RS is an important factor to enable digital precoding. For this reason, three types of CSI reporting mechanisms corresponding to three types of CSI-RS measurement operations, e.g., "CLASS A" CSI reporting corresponding to non-precoded CSI-RS, UE-specific beamforming applied ( beamformed) “CLASS B” reporting to K=1 CSI-RS resources corresponding to CSI-RS, and “CLASS B” reporting to K>1 CSI-RS corresponding to CSI-RS to which cell-specific beamforming is applied Supported.

For non-precoded (NP) CSI-RS, cell-specific one-to-one mapping between CSI-RS ports and TXRUs is utilized. Since different CSI-RS ports have the same wide beam width and direction, they generally have cell wide coverage. In the case of a CSI-RS to which beamforming is applied, a cell-specific or UE-specific beamforming operation is applied to non-zero-power (NZP) CSI-RS resources (eg, including multiple ports). At least at a given time/frequency, the CSI-RS port has a narrow beam width, so it is not cell-wide coverage, at least from the gNB point of view. At least some CSI-RS port-resource combinations have different beam directions.

In scenarios where the serving eNodeB can measure DL long-term channel statistics through UL signals, UE-specific BF CSI-RS can be easily used. This is generally possible when the UL-DL duplex distance is sufficiently small. However, if this condition does not hold, some UE feedback is required for the eNodeB to obtain an estimate of the DL long term channel statistics (or any representation thereof). To facilitate this procedure, the first BF CSI-RS is transmitted with a period of T1 (ms), and the second NP CSI-RS is transmitted with a period of T2 (ms), where T1 ≤ T2. This approach is called hybrid CSI-RS. The implementation of hybrid CSI-RS is highly dependent on the CSI process and the definition of NZP CSI-RS resources.

In wireless communication systems, MIMO is often identified as an essential feature to achieve high system throughput requirements. One of the key components of the MIMO transmission scheme is to accurately acquire CSI from the eNB (or gNB) (or TRP). In particular, in the case of MU-MIMO, availability of accurate CSI is required to ensure high MU performance. For TDD systems, CSI can be obtained using SRS transmission that relies on channel reciprocity. On the other hand, in the case of the FDD system, this can be obtained using CSI-RS transmission from the eNB (or gNB) and CSI acquisition and feedback from the UE. In legacy FDD systems, the CSI feedback framework is 'implicit' in the form of CQI/PMI/RI (also CRI and LI) derived from a codebook that assumes SU transmission from an eNB (or gNB). Due to the inherent SU assumption during CSI derivation, this implicit CSI feedback is not suitable for MU transmission. Since future (eg, NR) systems are likely to be more MU-centric, this SU-MU CSI mismatch will be the bottleneck in achieving high MU performance gains. Another issue with implicit feedback is scalability due to a larger number of antenna ports in an eNB (or gNB). For a large number of antenna ports, the codebook design for implicit feedback is quite complex (e.g., the total number of Class A codebooks in the 3GPP LTE specification is 44), and the designed codebooks have reasonable performance gains in real deployment scenarios. are not guaranteed to come (e.g., only a small percentage gain can be shown at best). Realizing the above problem, the 3GPP specification also supports advanced CSI reporting in LTE.

In 5G or NR systems [REF7, REF8], the above-mentioned “implicit” CSI reporting paradigm from LTE is also supported and is referred to as Type I CSI reporting. In addition, high-resolution CSI reporting, referred to as Type II CSI reporting, is also supported to provide more accurate CSI information to gNBs for use cases such as higher order MU-MIMO. However, overhead of Type II CSI reporting may be a problem in actual UE implementation. One approach to reducing Type II CSI overhead is based on frequency domain (FD) compression. In Re.16 NR, DFT-based FD compression of Type II CSI was supported (referred to as Rel.16 Enhanced Type II Codebook in REF8). Some of the key components of these features are (a) a spatial domain (SD) basis; , (b) FD basis and (c) coefficients linearly combining the SD and FD basis includes In a non-reciprocal FDD system, complete CSI (including all components) needs to be reported by the UE. However, when there is reciprocity or partial reciprocity between UL and DL, some CSI components may be obtained based on an estimated UL channel using SRS transmission from the UE. In Re.16 NR, DFT-based FD compression is extended to this partial reciprocity case (called Rel.16 enhanced Type II port selection codebook in REF8), where The DFT-based SD basis of is replaced by SD CSI-RS port selection, i.e. Of the CSI-RS ports is selected (the selection is common for both antenna polarizations or both halves of the CSI-RS ports). In this case, beamforming is applied to the CSI-RS port in SD (assuming UL-DL channel reciprocity in the angular domain), and beamforming information can be obtained from the gNB based on the UL channel estimated using SRS measurement. .

10 illustrates an exemplary Distributed MIMO (D-MIMO) system 1000 according to an embodiment of the present disclosure. The embodiment of Distributed MIMO (D-MIMO) system 1000 shown in FIG. 10 is for illustration only. 10 does not limit the scope of the present disclosure to any particular implementation of Distributed MIMO (D-MIMO) system 1000 .

NR supports up to 32 CSI-RS antenna ports. For cellular systems operating in the sub-1 GHz frequency range (e.g., sub-1 GHz), multiple CSI-RS antenna ports (e.g., 32) is difficult due to the larger antenna form factor at these frequencies (compared to systems operating at higher frequencies such as 2 GHz or 4 GHz). At these low frequencies, the maximum number of CSI-RS antenna ports that can be co-located in a site (or RRH) may be limited to eight, for example. This limits the spectral efficiency of these systems. In particular, the MU-MIMO spatial multiplexing gain provided by the large number of CSI-RS antenna ports (eg, 32) cannot be achieved. One way to operate a sub-1 GHz system with a large number of CSI-RS antenna ports is to distribute the antenna ports across multiple sites (or RRHs). Since multiple sites or RRHs can still be connected to a single (common) baseband unit, signals sent and received over multiple distributed RRHs can still be processed from a centralized location. For example, 32 CSI-RS ports can be spread over 4 RRHs with 8 antenna ports each. Such a MIMO system may be referred to as a distributed MIMO (D-MIMO) system as shown in FIG. 10 .

All of the following components and embodiments are applicable to UL transmission using DFT-spread OFDM (DFT-SOFDM) and single-carrier FDMA (SC-FDMA) waveforms as well as cyclic prefix OFDM (CP-OFDM) waveforms. In addition, all of the following components and embodiments are applicable to UL transmission when the scheduling unit of time is one subframe (which may consist of one or more slots) or one slot.

In this disclosure, the frequency resolution (reporting granularity) and span (reporting bandwidth) of CSI reporting are defined in terms of frequency "sub-band" and "CSI reporting band" (CRB), respectively. It can be.

A subband for CSI reporting is defined as a set of contiguous PRBs representing the minimum frequency unit for CSI reporting. The number of PRBs in a subband is fixed for a given value of DL system bandwidth, which is set semi-statically through higher layer/RRC signaling or dynamically through L1 DL control signaling or MAC control element (MAC CE). It can be. The number of PRBs in a subband may be included in the CSI reporting configuration.

A “CSI reporting band” is defined as the set/collection of contiguous or non-contiguous subbands on which CSI reporting is performed. For example, the CSI reporting band may include all subbands within the DL system bandwidth. This is also referred to as "full-band". Alternatively, the CSI reporting band may include only a set of subbands within the DL system bandwidth. This is also referred to as "partial band".

The term "CSI reporting band" is used only as an example to indicate functionality. Other terms such as "CSI reporting subband set" or "CSI reporting bandwidth" may also be used.

In terms of UE configuration, at least one CSI reporting band may be configured in the UE. This configuration can be semi-static (via higher layer signaling or RRC) or dynamic (via MAC CE or L1 DL control signaling). When multiple (N) CSI reporting bands are configured (eg, via RRC signaling), the UE may report CSI associated with n ≤ N CSI reporting bands. For example, if >6 GHz, large system bandwidths may require multiple CSI reporting bands. The value of n may be set semi-statically (via higher layer signaling or RRC) or dynamically (via MAC CE or L1 DL control signaling). Alternatively, the UE may report the recommended value of n via the UL channel.

Accordingly, the CSI parameter frequency granularity may be defined for each CSI reporting band as follows. If one CSI parameter for all M _n subbands is within the CSI reporting band, "single" reporting for the CSI reporting band with M _n subbands is set in the CSI parameter. When one CSI parameter is reported for each of the M _n subbands in the CSI reporting band, the "subband" for the CSI reporting band with M _n subbands is set in the CSI parameter.

11 shows an exemplary antenna port layout 1100 according to an embodiment of the present disclosure. The embodiment of the antenna port layout 1100 shown in FIG. 11 is for illustration only. 11 does not limit the scope of this disclosure to any particular implementation of antenna port layout 1100.

As shown in FIG. 11, N ₁ and N ₂ are the number of antenna ports having the same polarization in the first dimension and the second dimension, respectively. In the case of a 2D antenna port layout, N ₁ > 1 and N ₂ > 1, and in the case of a 1D antenna port layout, N ₁ > 1 and N ₂ = 1. Thus, in case of dual polarization antenna port layout, when each antenna is mapped to an antenna port, the total number of antenna ports is 2N ₁ N ₂ . An example is shown in Figure 11, where "X" represents two antenna polarizations. In this disclosure, the term "polarization" means a group of antenna ports. For example, the antenna port contains the first antenna polarization, and the antenna port contains the second antenna polarization, where is the number of CSI-Rs antenna ports, is the starting antenna port number (e.g., , and the antenna ports are 3000, 3001, 3002, ...).

Let be the number of antenna panels in the gNB. Multiple antenna panels ( ), each panel is a two-dimensional and Assume a dual polarized antenna port with a port. This is illustrated in FIG. 11 . The antenna port layout may or may not be the same in different antenna panels.

As described in section 5.2.2.2.1 of [REF 8], the Type I single panel codebook has the following rank 1 (1-layer) precoder structure:

here is the number of CSI-RS antenna ports, is the co-phase value across the two antenna polarizations,

is a two-dimensional DFT vector. The supported values for , which is the QPSK co-phase corresponds to The supported values of are given by Table 1.

Table 1: and of supported settings

As described in section 5.2.2.2.2 of [REF 8], the Type I multi-panel codebook has the following rank 1 (1-layer) precoder structure for codebookMode = 1:

here

The following rank 1 (1-layer) precoder structure for codebookMode = 2:

here

here is the number of CSI-RS antenna ports. If codebookMode = 1, , , , The supported values for each of , which is the QPSK statue corresponds to If codebookMode = 2, The supported values for , which is the QPSK statue represents, , The supported values for each of , which is a statue represents, , The supported values for each of , which is a statue indicates in other words,

The supported values of are given by Table 2.

Table 2: and of supported settings

Rel. 15 Type I single panel (SP) and Type I multi-panel (MP) codebook-based MIMO transmission examples are shown in FIG. 12 . Skilled artisans will appreciate that FIG. 12 illustrates an exemplary Type I single panel (SP) and Type I multi-panel (MP) codebook based MIMO transmission 1200 in accordance with an embodiment of the present disclosure. The embodiment of the Type I single panel (SP) and Type I multi-panel (MP) codebook based MIMO transmission 1200 illustrated in FIG. 12 is for illustration only. 12 does not limit the scope of this disclosure to any particular implementation of Type I single panel (SP) and Type I multi-panel (MP) codebook based MIMO transmissions 1200 .

In this disclosure, several codebook design alternatives for D-MIMO antenna structures are proposed.

In one example, the antenna architecture of a D-MIMO system is structured. For example, the antenna structure at each RRH is dual polarization (single or multi-panel as shown in FIG. 11). The antenna structure in each RRH may be the same. Alternatively, the antenna structure in an RRH may be different from other RRHs. Likewise, the number of ports in each RRH may be the same. Alternatively, the number of ports of one RRH may be different from that of another RRH.

In another example, the antenna architecture of a D-MIMO system is unstructured. For example, the antenna structure in one RRH may be different from that in another RRH.

In this disclosure, a structured antenna architecture is assumed.

In one embodiment I.1, a D-MIMO codebook is set in the UE (eg, through higher layer signaling), where the value for the number of RRHs is parameterized by

In one example I.1.1, The value of is fixed. for example, = 2 or 3 or 4 or 8.

In one example I.1.2, The value of is set as part of codebook configuration or CSI reporting configuration through RRC signaling, for example, or indicated through MAC CE or DCI or a combination of two or more of RRC, MAC CE, and DCI. The value of is set from the set of supported values. In one example, the set of supported values is or or or am.

In one example, A separate RRC parameter is used to set the value for .

In one example, the joint RRC parameter is It is used to set values for and at least one additional parameter. For example, Rel. 15 Parameters of Type I Multi-Panel Codebook Is and can be used as a common parameter for both.

In one example I.1.3, The value of (whether fixed or set) is affected by constraints (or conditions). In one example constraint, the total number of ports across all RRHs is the value or or or belongs to the set of

In one embodiment I.2, The total number of ports across all RRHs, denoted as , is determined according to at least one of the following examples.

In one example I.2.1, , where it is assumed that the antenna structure is the same in each RRH, that is, all About am. In one example, is, where is the first, assuming that the antenna structure can be different across RRHs. It is a parameter for RRH, i.e. am.

parameter is for example Rel. It can be set through RRC based on Table 1 for the 15 Type I single panel (or multi-panel) codebook. Likewise, each parameters for is for example Rel. It can be set through RRC based on Table 1 for the 15 Type I single panel (or multi-panel) codebook. In one example, is Rel. 15 Type I multi-panel codebook, analogous to Table 2, It is set (via RRC) by mapping to In one example, If , the value or am.

In example I.2.1A, , where it is assumed that the antenna structure is the same in each RRH, that is, all About am. In one example, is, where is the first, assuming that the antenna structure can be different across RRHs. This is a parameter for RRH. parameter may be set via RRC, for example from {2,4,8,12,16,24,32} or {4,8,12,16,24,32}. Likewise, each parameters for may be set via RRC, for example from {2,4,8,12,16,24,32} or {4,8,12,16,24,32}.

In one example, and value is is {4,8,12,16,24,32} or {4,8,12,16,24,32,48} or {4,8,12,16,24,32,48,64} or { 8,12,16,24,32} or {8,12,16,24,32,48} or {8,12,16,24,32,48,64}.

● In one example, when, is {2,4,8,12,16} or {2,4,8,12,16,24} or {2,4,8,12,16,24,32} or {4,8,12, 16} or {4,8,12,16,24} or {4,8,12,16,24,32}.

● In one example, when, is {2,4,8} or {2,4,8,12} or {2,4,8,12,16} or {4,8} or {4,8,12} or {4,8, 12,16}.

● In one example, when, belongs to {2,4} or {2,4,8} or {4} or {4,8}.

In one example, for The value and the different value of the total number of CSI-RS ports follow at least one of the examples in Table 3.

Table 3

In one example, the UE has distributed across all RRHs. One CSI-RS resource having a CSI-RS port is configured. In one example, the UE has CSI-RS resources are configured, where 1st with CSI-RS port CSI-RS resources are Associated with RRH.

In one example I.2.2, , where it is assumed that the antenna structure is the same in each RRH, that is, all About am. In one example, is, where is the first, assuming that the antenna structure can be different across RRHs. It is a parameter for RRH, i.e. am.

In one example I.2.3, is, where (eg, co-polarized antenna) or 2 (eg, dual polarized antenna), and assume that the antenna structure is the same in each RRH, that is, all About am. In one example, is, where = 1 or 2, is the first, assuming that the antenna structure can be different across RRHs. It is a parameter for RRH, i.e. am. The value of may be the same across RRHs. Alternatively, it may be different and thus may vary across RRHs.

In one embodiment I.3, CSI-RS port numbering for D-MIMO is according to at least one of the following examples.

In example I.3.1, the CSI-RS ports are numbered in the order of CSI-RS ports for RRH1, CSI-RS ports for RRH2, and the like.

In example I.3.2, the CSI-RS port is a CSI-RS port with primary polarization for RRH1, a CSI-RS port with secondary polarization for RRH1, and a CSI-RS port with primary polarization for RRH2. , the CSI-RS port having the second polarization for RRH2, and so on.

In example I.3.3, the CSI-RS port is a CSI-RS port with a first polarization for RRH1, a CSI-RS port with a first polarization for RRH2, ..., a CSI-RS port with a second polarization for RRH1. The CSI-RS ports are numbered in the order of the CSI-RS ports having the second polarization for RRH2.

In one example, a first polarization refers to the first half (first group) of antenna ports having a first antenna polarization (eg, +45), and a second polarization refers to the second antenna polarization (eg, -45 ) refers to the second half (second group) of antenna ports having.

In one embodiment II.1, a D-MIMO codebook is configured in the UE (eg, through higher layer signaling), and this codebook is, for example, Rel. A dual-stage precoder structure (for each layer) similar to (or based on) 15 NR Type II codebook, or for example Rel. It has a triple-stage precoder structure (for each layer) similar to (or based on) 16 NR Type II codebook. For 2-stage, the precoder for the layer is Can be represented as, where the component silver Used to report and represent a basis matrix containing n basis vectors, is common for both polarizations (for each layer) It is used to report and represent in-phase values for one and two polarizations of a selection of basis vectors. If Note that it is not necessary to select a beam via . For three stages, the dog's precoder Can be represented as, where the component is used to report and represent spatial domain (SD) basis matrices containing spatial domain (SD) basis vectors, and is used to report and represent the FD basis matrix containing the frequency domain (FD) basis vectors, and is used to report and represent coefficients corresponding to pairs of SD and FD basis vectors.

13 illustrates an exemplary D-MIMO 1300 in which each RRH has a single antenna panel according to an embodiment of the present disclosure. The embodiment of D-MIMO 1300 where each RRH has a single antenna panel shown in FIG. 13 is for illustration only. 13 does not limit the scope of this disclosure to any particular implementation of D-MIMO 1300 in which each RRH has a single antenna panel.

As shown in Figure 13, in one embodiment II.2, each RRH has a single antenna panel. Component Is It has a block diagonal structure comprising diagonal blocks, where a 1 (co-pol) or 2 (dual-pol) diagonal block is associated with each RRH.

In one example II.2.1, assuming a joint polarization (single polarization) antenna structure in each RRH am. In one example, When , component is given by:

here Is a basis matrix for the first RRH, Is a basis matrix for the second RRH. In one example, is the first for RRH Contains columns or beams (or basis vectors). In one example, all Value (RRH-common value) is, for example am. In one example, is RRH (RRH specific value), for example, can take a value (fixed or set) from {1,4}.

In one example II.2.2, assuming a dual polarization (cross polarization) antenna structure in each RRH am.

In one example, When , component is given by:

here Is the basis matrix for the first RRH and is common (equal) to the two polarizations corresponding to the first and second diagonal blocks, Is the basis matrix for the second RRH and is common (equal) to two polarizations corresponding to the third and fourth diagonal blocks. Generally, the and th Diagonal blocks are Corresponds to two antenna polarizations for RRH. In one example, is the first for RRH Contains columns or beams (or basis vectors). In one example, all Value (RRH Common value) and, for example, am. In one example, is RRH (RRH specific value), for example, can take a value (fixed or set) from {1,4}.

In one example, When , component is given by:

here Is the basis matrix for the first RRH and is common (equal) to the two polarizations corresponding to the first and third diagonal blocks, Is the basis matrix for the second RRH and is common (equal) to the two polarizations corresponding to the second and fourth diagonal blocks. Generally, the and th Diagonal blocks are Corresponds to two antenna polarizations for RRH. In one example, is the first for RRH Contains columns or beams (or basis vectors). In one example, all Value (RRH Common value) and, for example, am. In one example, is RRH (RRH specific value), for example, can take a value (fixed or set) from {1,4}.

In one example, When , component is given by:

here and Is a basis matrix for the first and second antenna polarizations of the first RRH corresponding to the first and second diagonal blocks, and Is a basis matrix for the first and second antenna polarizations of the second RRH corresponding to the third and fourth diagonal blocks. Generally, the and th Diagonal blocks are Corresponds to two antenna polarizations for RRH. In one example, is the first Article of RRH for polarization Contains columns or beams (or basis vectors). In one example, all and Value (RRH Common and Polarization Common value) and, for example, am. In one example, all Value (RRH specific and polarization common value) am. In one example, all Value (RRH common and polarization specific value) am. In one example, is RRH (RRH specific and polarization specific value) may vary.

In one example, When , component is given by:

here and Is a basis matrix for the first and second antenna polarizations of the first RRH corresponding to the first and third diagonal blocks, and Is a basis matrix for the first and second antenna polarizations of the second RRH corresponding to the second and fourth diagonal blocks. Generally, the and th Diagonal blocks are Corresponds to two antenna polarizations for RRH. In one example, is the first Article of RRH for polarization Contains columns or beams (or basis vectors). In one example, all and Value (RRH Common and Polarization Common value) and, for example, am. In one example, all Value (RRH specific and polarization common value) am. In one example, all Value (RRH common and polarization specific value) am. In one example, is RRH (RRH specific and polarization specific value) may vary.

In one example II.2.3, , where my For co-polarization (single polarization) antenna structure in RRH, is, and For dual polarization (cross polarization) antenna structure in RRH, am.

In one example, When , component is given by:

here Is a basis matrix for the first RRH, Is a basis matrix for the second RRH and is common (equal) to two polarizations corresponding to the second and third diagonal blocks.

In one example, When , component is given by:

here Is a basis matrix for the first RRH, and Is a basis matrix for the first and second antenna polarizations of the second RRH corresponding to the second and third diagonal blocks.

14 illustrates an exemplary D-MIMO 1400 in which each RRH has multiple antenna panels according to an embodiment of the present disclosure. The embodiment of D-MIMO 1400 where each RRH has multiple antenna panels shown in FIG. 14 is for illustration only. 14 does not limit the scope of this disclosure to any particular implementation of D-MIMO 1400 where each RRH has multiple antenna panels.

As shown in Figure 14, in one embodiment II.3, each RRH has multiple antenna panels. Component Is has a block diagonal structure containing diagonal blocks, where (co-polarization) or (double polarization) diagonal block is for all values of panel and Article containing Associated with RRH. For the two RRHs in FIG. 14 note that

Example II.2 is It can be extended in a simple way in this case (of multiple panels in RRH) by adding diagonal blocks corresponding to multiple panels in .

15 illustrates an exemplary D-MIMO 1500 in which each RRH may have a single antenna panel or multiple antenna panels according to an embodiment of the present disclosure. The embodiment of D-MIMO 1500 in which each RRH may have a single antenna panel or multiple antenna panels shown in FIG. 15 is for illustration only. 15 does not limit the scope of this disclosure to any particular implementation of D-MIMO 1500 in which each RRH may have a single antenna panel or multiple antenna panels.

As shown in Figure 15, in one embodiment II.4, each RRH may have a single antenna panel or multiple antenna panels. Component Is has a block diagonal structure containing diagonal blocks, where (co-polarization) or (double polarization) diagonal block is Article containing the panel Associated with RRH, When the RRH has a single panel is, and When RRH has multiple panels am.

Example II.2 is It can be extended in a simple way in this case (of multiple panels in RRH) by adding diagonal blocks corresponding to multiple panels in .

In one embodiment II.5, the component A basis matrix containing a diagonal block of , has columns selected from a set of oversampled 2D DFT vectors. When the antenna port layout is the same across RRHs, given the antenna port layout and the oversampling factor for 2 dimensions For, the DFT vector can be expressed as

here ego, am.

If the antenna port layout can differ across RRHs, given the antenna port layout assignment Oversampling factor associated with RRH For, the DFT vector can be expressed as

here ego, am.

In one example, the oversampling coefficient is RRH common and therefore remains the same across RRHs. for example, am. In one example, the oversampling coefficients are RRH specific and therefore independent for each RRH. for example, ego, is selected (fixed or set) from {2,4,8}.

In one example, the oversampling coefficient is fixed, for example, in the case of a low resolution (Type I) codebook , and in the case of a high-resolution (Type II) codebook am. In one example, the oversampling coefficient is set through, for example, RRC, where the set value is common to all RRHs or independent for each RRH (ie, one value is set for each RRH). .

In one embodiment II.6, each RRH may have a single antenna panel or multiple antenna panels (see FIG. 15).

Component Is has a block diagonal structure containing diagonal blocks, where (co-polarization) or (double polarization) diagonal block is Article containing the panel Associated with RRH, When the RRH has a single panel is, and When RRH has multiple panels am.

In one embodiment III.1, the codebook is Includes additional components due to RRH.

In Example III.1.1, the additional component includes another inter-RRH phase. In one example, the phase value between different RRHs is Corresponds to a phase value (eg assume that one of the RRHs is the reference and has a fixed phase value = 1). In another example, the phase value between different RRHs is Corresponds to the phase value. Phase values between different RRHs are quantized and reported as vectors using scalar codebooks (e.g., QPSK, 2 bits per phase or 8PSK, 3 bits per phase) or vector codebooks (e.g., DFT codebooks). It can be. In addition, in the case of a dual polarization antenna in an RRH, the phase between different RRHs may be the same for two polarizations of the RRH. Alternatively, it can be independent for both polarizations for RRH. At least one of the following examples is used for phase reporting between different RRHs.

- In Example III.1.1.1, the phase between different RRHs is reported in a wideband (WB) manner, that is, one value is reported for all SBs in the configured CSI reporting band. Due to WB reporting, this is components can be included. Alternatively, this is the codebook's can be included in new components, such as

- In Example III.1.1.2, the phase between different RRHs is reported in a sub-band (SB) manner, ie, one value is reported for each SB in the configured CSI reporting band. Due to SB reporting, this is components can be included. Alternatively, the codebook's can be included in new components, such as

● In Example III.1.1.3, the phase between different RRHs is reported in a WB plus SB manner, that is, one WB phase value is reported for all SBs in the configured CSI reporting band, and in the configured CSI reporting band. One SB value is reported for each SB. Due to WB plus SB reporting, the WB portion of the codebook component, and the SB part of the codebook components can be included. Alternatively, both the WB and SB parts of the codebook can be included in new components, such as

- In Example III.1.2, the additional components include phases between different RRHs and amplitudes between different RRHs, where details of the phases between different RRHs are as described in Example III.1.1. Note that different inter-RRH amplitudes are required due to the different distances of the UEs from the RRHs. In one example, the amplitude values between different RRHs are Corresponds to the amplitude value (assuming, for example, that one of the RRHs is the reference and has a fixed amplitude value = 1). In another example, the amplitude values between different RRHs are Corresponds to the amplitude value. Amplitude values between different RRHs may be quantized and reported as a scalar using a scalar codebook (eg, 2 bits per amplitude or 3 bits per amplitude) or as a vector using a vector codebook. In addition, in the case of a dual polarization antenna in an RRH, amplitudes between different RRHs may be the same for two polarizations of the RRH. Alternatively, it can be independent for both polarizations for RRH. At least one of the following examples is used for amplitude and phase reporting between different RRHs.

- In Example III.1.2.1, amplitudes between different RRHs are reported in a wideband (WB) manner, that is, one value is reported for all SBs in the configured CSI reporting band. Due to WB reporting, this is components can be included. Alternatively, this is the codebook's can be included in new components, such as At least one of the following examples is used for phases between different RRHs.

o In Example III.1.2.1.1, phases between different RRHs are reported according to Example III.1.1.1.

o In Example III.1.2.1.2, phases between different RRHs are reported according to Example III.1.1.2.

o In Example III.1.2.1.3, the phase between different RRHs is reported according to Example III.1.1.3.

- In Example III.1.2.2, the amplitudes between different RRHs are reported in a sub-band (SB) manner, ie, one value is reported for each SB in the configured CSI reporting band. Due to SB reporting, this is components can be included. Alternatively, this is the codebook's can be included in new components, such as At least one of the following examples is used for phases between different RRHs.

o In Example III.1.2.2.1, phases between different RRHs are reported according to Example III.1.1.1.

o In Example III.1.2.2.2, the phase between different RRHs is reported according to Example III.1.1.2.

o In Example III.1.2.2.3, the phase between different RRHs is reported according to Example III.1.1.3.

● In Example III.1.2.3, amplitudes between different RRHs are reported in a WB plus SB manner, that is, one WB amplitude value is reported for all SBs in the configured CSI reporting band, and in the configured CSI reporting band. One SB value is reported for each SB. Due to WB plus SB reporting, the WB portion of the codebook component, and the SB part of the codebook components can be included. Alternatively, both the WB and SB parts of the codebook can be included in new components, such as At least one of the following examples is used for phases between different RRHs.

o In Example III.1.2.3.1, phases between different RRHs are reported according to Example III.1.1.1.

o In Example III.1.2.3.2, the phase between different RRHs is reported according to Example III.1.1.2.

o In Example III.1.2.3.3, phases between different RRHs are reported according to Example III.1.1.3.

In Example III.1.3, the additional component includes amplitudes between different RRHs, where details of amplitudes between different RRHs are as described in Example III.1.2.

In Example III.1.4, the additional component includes power between different RRHs, where details of power between different RRHs are as described in Example III.1.2 by replacing amplitude with power. In one example, the square of the amplitude between different RRHs equals the power between different RRHs.

In Example III.1.5, the additional components include a phase between different RRHs and a power between different RRHs, where the details of the phase between different RRHs are as described in Example III.1.1, and the power between different RRHs Details are as described in Example III.1.2 by substituting power for amplitude. In one example, the square of the amplitude between different RRHs equals the power between different RRHs.

In Example III.1.6, the additional element includes an indicator indicating the strongest RRH (for reference). Due to the distributed architecture, the strongest RRH may be reported to represent the reference RRH for which other inter-RRH components (eg, amplitude or/and phase) are reported. The amplitude and phase between other RRHs associated with the strongest RRH may be set to a fixed value, eg 1. At least one of the following examples is used for the strongest RRH report.

- In Example III.1.6.1, the strongest RRH (indicator) is reported in a WB manner, ie, one value (indicator) is reported for all SBs. Due to WB reporting, this is components can be included. Alternatively, this is the codebook's can be included in new components, such as

- In Example III.1.6.2, the strongest RRH (indicator) is reported in the SB manner, ie one value (indicator) is reported for each SB. Due to SB reporting, this is components can be included. Alternatively, this is the codebook's can be included in new components, such as

In one example, the strongest RRH is reported in a layer common manner, that is, one strongest RRH common to all layers is reported when the number of layers > 1 (or rank > 1).

In one example, the strongest RRH is reported in a layer specific manner, ie, one strongest RRH is reported for each layer in the number of layers when number of layers > 1 (or rank > 1).

The amplitude/phase associated with the strongest RRH may be fixed at 1, for example. In an alternative design, the strongest RRH may be established (e.g., via RRC signaling), indicated (via MAC CE or DCI or a combination of two or more of RRC, MAC CE and DCI), or may be fixed. (For example, RRH 1 is always the strongest).

In one embodiment III.1.4, RRH selection is performed, where A subset of RRH is is selected from RRH, and CSI is selected Reported for RRH. In one example, RRH selection may be configured through RRC signaling, or indicated through MAC CE or DCI or a combination of two or more of RRC, MAC CE, and DCI. In another example, RRH selection is performed by the UE, eg, the UE reports an indicator for this selection or reports amplitude (or power) = 0 between different RRHs indicating that the RRH is not selected.

In one example, RRH selection is reported in a layer common manner, that is, when the number of layers > 1 (or rank > 1), RRH selection is performed in common for all layers.

In one example, RRH selection is reported in a layer-specific manner, ie, RRH selection is performed for each layer in the number of layers when number of layers > 1 (or rank > 1).

In Example III.1.4.1, a Type I codebook for D-MIMO is set in the UE (eg, by setting the RRC parameter codebookType = TypeI-D-MIMO), where the codebook is a component for RRH selection. (ON/OFF).

In one example, this component is separate (dedicated to RRH selection). for example, A bit sequence comprising bits is used, where each bit of the bit sequence is associated with an RRH, a bit value '1' is used to indicate that the RRH is selected, and a bit value '0' indicates that the RRH is not selected. used to for example, The combination index indicated through bit signaling is RRH selection hypothesis, Rel. It is used to indicate W1 basis vector selection in the 15 NR Type I codebook.

In another example, this component is combined (joint) with the amplitude component of the codebook, where the amplitude codebook contains the value 0 (in addition to other values greater than 0), and the value '0' is selected by the RRH. A bit value greater than zero is used to indicate and report that RRH is selected, and the indicated and reported value represents the amplitude weight in the precoder equation/calculation.

In Example III.1.4.2, the UE has a Type II codebook (or Type II port) for D-MIMO (eg, by setting the RRC parameter codebookType = TypeII-D-MIMO or TypeII-PortSelection-D-MIMO). selection) is set, where the codebook includes components (ON/OFF) for RRH selection.

In one example, this component is separate (dedicated to RRH selection). for example, A bit sequence comprising bits is used, where each bit of the bit sequence is associated with an RRH, a bit value '1' is used to indicate that the RRH is selected, and a bit value '0' indicates that the RRH is not selected. used to for example, The combination index indicated through bit signaling is RRH selection hypothesis, Rel. It is used to indicate W1 basis vector selection in the 15 NR Type I codebook.

In another example, this component is combined (joint) with the amplitude component of the codebook, where the amplitude codebook contains the value 0 (in addition to any other value greater than 0), and the value '0' indicates that RRH is not selected. A bit value greater than zero is used to indicate and report that RRH is selected, and the indicated and reported value represents the amplitude weight in the precoder equation/calculation.

In Example III.1.4.3, the UE is configured to report CSI based on the D-MIMO codebook using UCI part 1 and UCI part 2 of the two-part UCI, and UCI part 1 is used to indicate and report RRH selection. used In one example, the two-part UCI is configured only when the UE is configured to report SB CSI reporting based on the D-MIMO codebook. In one example, the two-part UCI is configured only when a Type II or Type II port selection codebook for D-MIMO is configured in the UE.

In Example III.1.4.4, the UE is set to report CSI based on the D-MIMO codebook using UCI part 1 and UCI part 2 of the two-part UCI, and UCI part 2 is used to indicate and report RRH selection. used In one example, the two-part UCI is configured only when the UE is configured to report SB CSI reporting based on the D-MIMO codebook. In one example, the two-part UCI is configured only when a Type II or Type II port selection codebook for D-MIMO is configured in the UE.

In Example III.1.4.5, the UE is configured to report CSI based on the D-MIMO codebook using one partial UCI used to indicate and report RRH selection. In one example, one partial UCI is configured only when the UE is configured to report WB CSI reporting based on the D-MIMO codebook. In one example, one partial UCI is configured only when a Type I codebook for D-MIMO is configured in the UE.

In one example, two part UCI (part 1 and part 2) for CSI reporting are configured in the UE based on the D-MIMO codebook.

- In one example, UCI part 1 includes information about RRH selection.

- In one example, UCI part 1 contains the strongest RRH information.

- In one example, UCI part 1 includes both the strongest RRH information and information on RRH selection.

- In one example, UCI part 2 includes information about RRH selection.

- In one example, UCI part 2 contains the strongest RRH information.

- In one example, UCI part 2 includes both the strongest RRH information and information on RRH selection.

In one example, one partial UCI for RRH selection reporting is configured in the UE.

- In one example, this configuration is limited to the case where WB CSI reporting is configured (ie, in the case of SB CSI reporting, a two-part UCI is used to report RRH selection).

- In one example, this setting is limited to the case where a Type I codebook for D-MIMO is set (ie, in the case of a Type II codebook, a two-part UCI is used to report RRH selection).

In one example, one partial UCI for the strongest RRH reporting is configured in the UE.

- In one example, this configuration is limited to the case where WB CSI reporting is configured (ie, in the case of SB CSI reporting, a two-part UCI is used to report RRH selection).

- In one example, this setting is limited to the case where a Type I codebook for D-MIMO is set (ie, in the case of a Type II codebook, a two-part UCI is used to report RRH selection).

In one example, a UE is configured with one partial UCI for both RRH selection and strongest RRH reporting.

- In one example, this configuration is limited to the case where WB CSI reporting is configured (ie, in the case of SB CSI reporting, a two-part UCI is used to report RRH selection).

In one example, this configuration is limited to the case where a Type I codebook for D-MIMO is configured (ie, in the case of a Type II codebook, a two-part UCI is used to report RRH selection).

In one example, the parameter is fixed to 2, for example. In one example, the parameter Is set through RRC, for example. In one example, the parameter is reported by the UE via UCI part 1 of a two-part UCI including part 1 and part 2, for example. reported value is the minimum It can be based on, that is, the UE random to can report Alternatively, reported value is the maximum It can be based on, that is, the UE random to can report Alternatively, reported value is the minimum and max It can be based on, that is, the UE random to can report or/and The value may be fixed, set (eg RRC) or reported by the UE as part of the UE capability report.

● In one example, indicating the selected RRH and indicators are all reported via UCI Part 1.

● In one example, is reported through UCI part 1, and an indicator indicating the selected RRH is reported through UCI part 2.

In this disclosure, the codebook component Is the first PMI indicator Refers to a precoder (or precoding matrix) component represented through a component of . Similarly, the codebook component Is the second PMI indicator Refers to a precoder (or precoding matrix) component represented through a component of . Similarly, the new codebook component Is the third PMI indicator Refers to a precoder (or precoding matrix) component represented through a component of .

In one embodiment IV.1, the codebook for D-MIMO transmission has one of the following designs.

In Example IV.1.1, the codebook has a separate (separate) design for components between different RRHs and within the same RRH (intra-RRH). For example, (Inter-RRH, Intra-RRH) = (Type I, Type I) or (Type II, Type I) or (Type I, Type II), or (Type II, Type II), where Type I found that the corresponding codebook component is Rel. It means that it has similarity with the 15 NR Type I codebook. Similarly, Type II indicates that the corresponding codebook component is Rel. It means that it has similarity with the 15 or 16 NR Type II codebook.

In Example IV.1.2, the codebook has a joint (joint) design between different RRHs and components within the same RRH. For example, (Inter-RRH, Intra-RRH) has a Type I or Type II design.

In one embodiment IV.2, A component has one of the following high-level designs:

In one example IV.2.1, Components have a Type I structure. In one example, or only , i.e. only one beam or basis vector is used for each layer (or precoder for each layer). In one example, in or (e.g. 4) is used, i.e. contains a number of beams or basis vectors, but the UE for each layer (or precoder for each layer) Select one beam or basis vector among the two beams. In one example, the UE has at or is set, and the UE accordingly select and report

● Design 1:

o Single panel: cross-pol co-phase, phase between different RRHs

o Multi-panel: cross-polarized in-phase, phase between different panels, phase between different RRHs

● Design 2:

o Single panel: joint frostbite

o Multi-panel: At least two or all of cross-polarized in-phase, phase between different panels, and phase between different RRHs are joint.

In one example IV.2.2, Components have a Type II structure. In one example, ego, The value of is set from a set of supported values (eg, via RRC signaling). In one example, the set of supported values is belongs to

● Design 1:

o Separate amplitude components for polarization and/and panel or/and RRH

● Design 2:

o joint amplitude

In one embodiment IV.3, the D-MIMO codebook includes both coherent and non-coherent pre-coders, where all entries are non-zero precoders or pre-coders. Corresponds to a coding matrix, and a noncoherent precoder corresponds to a precoder or precoding matrix in which each row or each column has at least one zero entry.

Any of the variants described above may be used independently or in combination with at least one other variant.

16 shows a flow diagram of a method 1600 of operating a user equipment (UE) as may be performed by a UE, such as UE 116, in accordance with an embodiment of the present disclosure. The embodiment of method 1600 shown in FIG. 16 is for illustration only. 16 does not limit the scope of the disclosure to any particular implementation.

As shown in FIG. 16 , method 1600 begins at step 1602 . At step 1602, the UE (eg, 111-116 as shown in FIG. 1) receives information regarding a channel state information (CSI) report, the information being number > 1 and RRH , where: = number of remote radio heads (RRH), RRH Is Contains a group of channel state information reference signal (CSIRS) antenna ports, r = 1,..., am.

At step 1604, the UE Select the strongest RRH from the RRHs.

In step 1606, the UE determines the CSI report containing the indicator indicating the strongest RRH.

At step 1608, the UE transmits a CSI report including an indicator indicating the strongest RRH.

In one embodiment, each RRH About, the information is contains information about

In one embodiment, ego, information about corresponds to the value of

In one embodiment, the strongest RRH is reported as a wideband (WB) or subband (SB), where WB corresponds to a single value common to all subbands in the CSI reporting band and SB corresponds to multiple values. and one value for each subband in the CSI reporting band.

In one embodiment, the strongest RRH is reported as layer common or layer specific, where layer common corresponds to a single value common to all layers, layer specific corresponds to multiple values, and one value corresponds to each layer. It is about.

In one embodiment, the amplitude associated with the strongest RRH = 1.

In one embodiment, the UE During RRH Determines a CSI report including an indicator indicating the selected RRH selection, and the CSI report Selected among RRHs is determined about am.

In one embodiment, the indicator indicating RRH selection is length bit sequence of is, where is RRH indicates that is not selected, Silver RRH indicates that is selected.

In one embodiment, the indicator indicating RRH selection is is a bit combinatorial indicator, where is the ceiling function.

In one embodiment, the indicator indicating RRH selection is an amplitude value for each RRH ( ), where is RRH indicates that is not selected, is RRH indicates that is selected.

In one embodiment, RRH selections are reported as layer-common or layer-specific, where layer-common corresponds to a single value common to all layers, layer-specific corresponds to multiple values, and one value corresponds to each layer. it is about

In one embodiment, the UE transmits the CSI report through two-part uplink control information (UCI) including part 1 and part 2, and UCI part 1 includes information on RRH selection.

17 shows a flow diagram of another method 1700 as may be performed by a base station (BS), such as BS 102, in accordance with an embodiment of the present disclosure. The embodiment of method 1700 shown in FIG. 17 is for illustration only. 17 does not limit the scope of the present disclosure to any particular implementation.

As shown in FIG. 17 , method 1700 begins at step 1702 . At step 1702, the BS (e.g., 101-103 as shown in Figure 1) generates information about a channel state information (CSI) report, which information is > 1 and RRH , where: = number of remote radio heads (RRH), RRH Is Contains a group of channel state information reference signal (CSIRS) antenna ports, r = 1,..., am.

At step 1704, the BS transmits information.

At step 1706, BS A CSI report including an indicator indicating the strongest RRH selected from RRHs is received.

In one embodiment, each RRH About, the information is contains information about

In one embodiment, ego, information about corresponds to the value of

In one embodiment, the strongest RRH is reported as a wideband (WB) or subband (SB), where WB corresponds to a single value common to all subbands in the CSI reporting band and SB corresponds to multiple values. and one value for each subband in the CSI reporting band.

The foregoing flowcharts illustrate example methods that may be implemented in accordance with the principles of the present disclosure, and various changes may be made to the methods depicted in the flowcharts herein. For example, although shown as a series of steps, the various steps in each figure may overlap, occur in parallel, occur in a different order, or occur multiple times. In other examples, steps may be omitted or replaced with other steps.

Although the present disclosure has been described with exemplary embodiments, various changes and modifications may be suggested to those skilled in the art. This disclosure is intended to cover such changes and modifications as fall within the scope of the appended claims. The description in this application is not to be construed as implying that any particular element, step or function is an essential element that must be included in the scope of the claims. The scope of the patented subject matter is defined by the claims.

Claims (15)

In the user equipment (UE),
A transceiver configured to receive information regarding a channel state information (CSI) report, wherein the information is > 1 and RRH Including, = number of remote radio heads (RRH), RRH Is Contains a group of channel state information reference signal (CSIRS) antenna ports, r = 1,..., In, the transceiver; and
a processor operably coupled to the transceiver, wherein the processor, based on the information,:
remind select the strongest RRH from the RRHs;
configured to determine the CSI report including an indicator indicating the strongest RRH;
wherein the transceiver is configured to transmit the CSI report including the indicator indicating the strongest RRH. According to claim 1,
each RRH For , the above information is contains information about ego, information about Corresponding to the value of the user equipment (UE). According to claim 1,
The strongest RRH is reported as wideband (WB) or subband (SB), where WB corresponds to a single value common to all subbands in the CSI reporting band, and SB corresponds to multiple values, one value where n is for each subband in the CSI reporting band. According to claim 1,
The strongest RRH is reported as layer-common or layer-specific, where layer-common corresponds to a single value common to all layers, and layer-specific corresponds to multiple values, one value for each layer. , user equipment (UE). According to claim 1,
The amplitude associated with the strongest RRH = 1, User Equipment (UE). According to claim 1,
The processor said During RRH and further configured to determine the CSI report including an indicator indicating the selected RRH selection, and the CSI report includes the Selected among RRH is determined about , user equipment (UE). According to claim 6,
The indicator indicating the RRH selection is length bit sequence of is, is RRH indicates that is not selected, Silver RRH A user equipment (UE), indicating that is selected. According to claim 6,
The indicator indicating the RRH selection is is a bit combination indicator, is a ceiling function, user equipment (UE). According to claim 6,
The indicator indicating the RRH selection is an amplitude value for each RRH ( ), is RRH indicates that is not selected, is RRH A user equipment (UE), indicating that is selected. According to claim 6,
The RRH selection is reported as layer common or layer specific, the layer common corresponds to a single value common to all layers, and the layer specific corresponds to multiple values, one value for each layer. , user equipment (UE). According to claim 6,
The transceiver is configured to transmit the CSI report through a two-part uplink control information (UCI) comprising part 1 and part 2, wherein UCI part 1 includes information on the RRH selection. In the base station (BS),
A processor configured to generate information relating to a channel state information (CSI) report, wherein the information is > 1 and RRH Including, = number of remote radio heads (RRH), RRH Is Contains a group of channel state information reference signal (CSIRS) antenna ports, r = 1,..., phosphorus, the processor; and
a transceiver operably coupled to the processor, the transceiver comprising:
send the information;
It is set to receive the CSI report,
The CSI report is A base station (BS), including an indicator indicating the strongest RRH selected from the RRHs. According to claim 12,
each RRH For , the above information is contains information about ego, information about corresponds to the value of
The strongest RRH is reported as a wideband (WB) or subband (SB), where WB corresponds to a single value common to all subbands in the CSI reporting band, and SB corresponds to multiple values, one value where β is for each subband in the CSI reporting band. A method of operating a user equipment (UE),
Receiving information about a channel state information (CSI) report, wherein the information is > 1 and RRH Including, = number of remote radio heads (RRH), RRH Is Contains a group of channel state information reference signal (CSIRS) antenna ports, r = 1,..., In, the receiving step;
remind selecting the strongest RRH from the RRHs;
determining the CSI report including an indicator indicating the strongest RRH; and
and transmitting the CSI report including the indicator indicating the strongest RRH. In the method of operating a base station (BS),
A step of generating information about a channel state information (CSI) report, wherein the information is > 1 and RRH Including, = number of remote radio heads (RRH), RRH Is Contains a group of channel state information reference signal (CSIRS) antenna ports, r = 1,..., phosphorus, the generating step;
sending the information; and
Receiving the CSI report;
The CSI report is A method of operating a base station (BS) comprising an indicator indicating the strongest RRH selected from the RRHs.

Images