CN116325614A

CN116325614A - Indication of frequency domain components

Info

Publication number: CN116325614A
Application number: CN202080106309.2A
Authority: CN
Inventors: 刘皓; F·托萨托; R·阿梅德
Original assignee: Nokia Shanghai Bell Co Ltd; Nokia Solutions and Networks Oy
Current assignee: Nokia Shanghai Bell Co Ltd; Nokia Solutions and Networks Oy
Priority date: 2020-10-16
Filing date: 2020-10-16
Publication date: 2023-06-23
Also published as: EP4229766A1; WO2022077463A1

Abstract

Embodiments of the present disclosure relate to the indication of frequency domain components. A method, comprising: responsive to receiving a first plurality of reference signals from a second device on physical resource blocks in a subband, determining, at the first device, first information regarding whether frequency domain components associated with the subband are selected for at least one data stream; determining at least one codebook for the first information based on the first configuration; and transmitting a subset of the second plurality of reference signals having the at least one codebook to the second device over a portion of the physical resource blocks. The method further comprises the steps of: receiving, at a second device, a second plurality of reference signals; determining first information based on the first and second configurations; and transmitting channel state information to the first device based on the first information. In this way, frequency domain component selection may be dynamically indicated from the first device to the second device with low overhead.

Description

Indication of frequency domain components

Technical Field

Embodiments of the present disclosure relate generally to the field of telecommunications and, more particularly, relate to a method, apparatus, and computer-readable storage medium for communication indicating Frequency Domain (FD) components.

Background

With the development of New Radio (NR) multiple-input multiple-output (MIMO) technology, it is agreed that information about angles and delays is estimated at a network device based on Sounding Reference Signals (SRS) from a terminal device by Downlink (DL)/Uplink (UL) reciprocity using angles and delays. In some cases, the network device may estimate the UL SRS to obtain delay related information, e.g., FD component, which may be the same as the selection by the DL channel state information reference signal (CSI-RS) at the terminal device. Thus, the terminal device does not need an index of FD component selected for CSI reporting to save the payload.

However, due to a large frequency duplex distance or limited UL SRS resources or SRS estimation error, etc., the selection of FD components may not be aligned for the network device and terminal device sides. In this case, CS quantization accuracy and system performance will be affected. Therefore, how to ensure alignment of the selected FD component between the network device and the terminal device side has become a hotspot problem.

Disclosure of Invention

In general, exemplary embodiments of the present disclosure provide a solution for indicating FD components.

In a first aspect, a first device is provided. The first device includes: at least one processor; and at least one memory including computer program code; the at least one memory and the computer program code are configured to, with the at least one processor, cause the first device to: responsive to receiving a first plurality of reference signals from a second device on physical resource blocks in a subband, determining first information regarding whether a frequency domain component associated with the subband is selected for at least one data stream; determining at least one codebook for the first information based on a first configuration, the first configuration indicating a mapping between one or more candidate content of the first information and one or more corresponding codebooks; and transmitting a second plurality of reference signals having at least one codebook to a second device on a portion of the physical resource blocks, the portion of the physical resource blocks determined from a second configuration indicating whether the at least one codebook is to be carried for the physical resource blocks.

In a second aspect, a second device is provided. The second device includes: at least one processor; and at least one memory including computer program code; the at least one memory and the computer program code are configured to, with the at least one processor, cause the second device to: receiving a second plurality of reference signals from the first device on physical resource blocks in the sub-band; determining first information regarding whether frequency domain components associated with the subbands are selected for the at least one data stream based on first and second configurations, the first configuration indicating a mapping between one or more candidate content of the first information and one or more corresponding codebooks, and the second configuration indicating whether the at least one codebook is to be carried for the physical resource block; and transmitting channel state information to the first device based on the first information.

In a third aspect, a communication method is provided. The method comprises the following steps: responsive to receiving a first plurality of reference signals from a second device on physical resource blocks in a subband, determining, at the first device, first information regarding whether a frequency domain component associated with the subband is selected for at least one data stream; determining at least one codebook for the first information based on a first configuration, the first configuration indicating a mapping between one or more candidate content of the first information and one or more corresponding codebooks; and transmitting a subset of the second plurality of reference signals having at least one codebook to the second device on a portion of the physical resource blocks, the portion of the physical resource blocks determined from a second configuration, the second configuration indicating whether the at least one codebook is to be carried for the physical resource blocks.

In a fourth aspect, a communication method is provided. The method comprises the following steps: at the second device, receiving a second plurality of reference signals from the first device on physical resource blocks in the sub-band; determining first information regarding whether frequency domain components associated with the subbands are selected for the at least one data stream based on first and second configurations, the first configuration indicating a mapping between one or more candidate content of the first information and one or more corresponding codebooks, and the second configuration indicating whether the at least one codebook is to be carried for the physical resource block; and transmitting channel state information to the first device based on the first information.

In a fifth aspect, a communication device is provided. The device comprises: means for determining, at the first device, first information regarding whether a frequency domain component associated with a subband is selected for at least one data stream in response to receiving a first plurality of reference signals from a second device over a physical resource block in the subband; means for determining at least one codebook for the first information based on a first configuration, the first configuration indicating a mapping between one or more candidate content of the first information and one or more corresponding codebooks; and means for transmitting a second plurality of reference signals with at least one codebook to a second device on a portion of physical resource blocks, the portion of physical resource blocks determined from a second configuration indicating whether the at least one codebook is to be carried for the physical resource blocks.

In a sixth aspect, a communication device is provided. The device comprises: means for receiving, at the first device, a second plurality of reference signals from the first device on physical resource blocks in the subband; determining first information regarding whether frequency domain components associated with the subbands are selected for the at least one data stream based on first and second configurations, the first configuration indicating a mapping between one or more candidate content of the first information and one or more corresponding codebooks, and the second configuration indicating whether the at least one codebook is to be carried for a physical resource block; and means for transmitting channel state information to the first device based on the first information.

In a seventh aspect, a non-transitory computer readable medium is provided. The non-transitory computer readable medium comprises program instructions for causing an apparatus to perform the method according to the third aspect.

In an eighth aspect, a non-transitory computer-readable medium is provided. The non-transitory computer readable medium includes program instructions for causing an apparatus to perform the method according to the fourth aspect.

It should be understood that the summary is not intended to identify key or essential features of the embodiments of the disclosure, nor is it intended to be used to limit the scope of the disclosure. Other features of the present disclosure will become apparent from the following description.

Drawings

Some example embodiments will now be described with reference to the accompanying drawings, in which:

FIG. 1 illustrates an example communication network in which exemplary embodiments of the present disclosure may be implemented;

fig. 2 illustrates a diagram of RS transmissions on Physical Resource Blocks (PRBs) in a Subband (SB) according to some embodiments of the present disclosure;

FIG. 3 illustrates a flow chart of a communication process according to some embodiments of the present disclosure;

FIG. 4 illustrates a diagram of an example bit string configuration, according to some embodiments of the present disclosure;

FIG. 5 illustrates a diagram of an example bit string configuration, according to some embodiments of the present disclosure;

FIG. 6 illustrates a diagram of an example bit string configuration, according to some embodiments of the present disclosure;

FIG. 7 illustrates a diagram of an example bit string configuration, according to some embodiments of the present disclosure;

FIG. 8 illustrates a diagram of an example bit string configuration, according to some embodiments of the present disclosure;

FIG. 9 illustrates a diagram of an example bit string configuration, according to some embodiments of the present disclosure;

fig. 10 illustrates a diagram of transmission of a codebook on a beamformed CSI-RS in accordance with some embodiments of the present disclosure;

FIG. 11 illustrates a flowchart of a communication method implemented at a first device according to an example embodiment of the present disclosure;

fig. 12 illustrates a flowchart of a communication method implemented at a second device according to an example embodiment of the present disclosure;

FIG. 13 illustrates a simplified block diagram of an apparatus suitable for practicing the example embodiments of the present disclosure; and

fig. 14 illustrates a block diagram of an example computer-readable medium, according to an example embodiment of the present disclosure.

The same or similar reference numbers will be used throughout the drawings to refer to the same or like elements.

Detailed Description

Principles of the present disclosure will now be described with reference to some example embodiments. It should be understood that these embodiments are described for illustrative purposes only and to assist those skilled in the art in understanding and practicing the present disclosure without implying any limitation on the scope of the present disclosure. The disclosure described herein may be implemented in various ways other than those described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

References in the present disclosure to "one embodiment," "an example embodiment," etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Furthermore, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to effect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

It will be understood that, although the terms "first" and "second," etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term "and/or" includes any and all combinations of one or more of the listed terms.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises," "comprising," "has," "including," "includes" and/or "including" when used herein, specify the presence of stated features, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, elements, components, and/or groups thereof.

As used in this application, the term "circuitry" may refer to one or more or all of the following:

(a) Pure hardware circuit implementations (such as implementations using only analog and/or digital circuitry), and

(b) A combination of hardware circuitry and software, such as (as applicable):

(i) Combination of analog and/or digital hardware circuit(s) and software/firmware, and

(ii) Any portion of the hardware processor(s) with software, including

Digital signal processor, software and memory(s) that work together to cause a device, such as a mobile phone or server, to perform various functions, and

(c) Hardware circuit(s) and/or processor(s), such as microprocessor(s) or a portion of microprocessor(s), that require software (e.g., firmware)

The operation is performed, but the software may not exist when the operation is not required.

The definition of circuitry is applicable to all uses of that term in this application, including in any claims. As another example, as used in this application, the term circuitry also encompasses hardware-only circuitry or a processor (or multiple processors) or an implementation of a hardware circuit or portion of a processor and its accompanying software and/or firmware. For example, if applicable to the particular claim elements, the term circuitry also encompasses a baseband integrated circuit or processor integrated circuit for a mobile device, or a similar integrated circuit in a server, a cellular network device, or other computing or network device.

As used herein, the term "communication network" refers to a network that conforms to any suitable communication standard, such as a fifth generation (5G) system, long Term Evolution (LTE), LTE-advanced (LTE-a), wideband Code Division Multiple Access (WCDMA), high Speed Packet Access (HSPA), narrowband internet of things (NB-IoT), and so forth. Furthermore, the communication between the terminal device and the network device in the communication network may be performed according to any suitable generation communication protocol, including, but not limited to, first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, fifth generation (5G) New Radio (NR) communication protocols, and/or any other protocol currently known or to be developed in the future. Embodiments of the present disclosure may be applied to various communication systems. In view of the rapid development of communications, there are, of course, future types of communication techniques and systems that can embody the present disclosure. It should not be taken as limiting the scope of the invention to only the above-described systems.

As used herein, the term "network device" refers to a node in a communication network via which a terminal device accesses the network and receives services therefrom. Depending on the terminology and technology applied, a network device may refer to a Base Station (BS) or Access Point (AP), e.g., a node B (NodeB or NB), an evolved node B (eNodeB or eNB), an NR NB (also referred to as a gNB), a Remote Radio Unit (RRU), a Radio Head (RH), a Remote Radio Head (RRH), a relay, a low power node such as femto, pico, etc. The RAN split architecture includes a gNB-CU (centralized unit, hosting RRC, SDAP, and PDCP) that controls multiple gNB-DUs (distributed units, hosting RLC, MAC, and PHY). The relay node may correspond to the DU portion of the IAB node.

The term "terminal device" refers to any terminal device capable of wireless communication. By way of example and not limitation, a terminal device may also be referred to as a communication device, a User Equipment (UE), a Subscriber Station (SS), a portable subscriber station, a Mobile Station (MS), or an Access Terminal (AT). The terminal devices may include, but are not limited to, mobile phones, cellular phones, smart phones, voice over IP (VoIP) phones, wireless local loop phones, tablets, wearable terminal devices, personal Digital Assistants (PDAs), portable computers, desktop computers, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback devices, in-vehicle wireless terminal devices, wireless endpoints, mobile stations, laptop embedded devices (LEEs), notebook computer mounted devices (LMEs), USB dongles, smart devices, wireless client devices (CPE), internet of things (IoT) devices, watches or other wearable devices, head Mounted Displays (HMDs), vehicles, drones, medical devices and applications (e.g., tele-surgery), industrial devices and applications (e.g., robots and/or other wireless devices operating in an industrial and/or automated processing chain environment), consumer electronics devices, devices operating on commercial and/or industrial wireless networks, and the like. The terminal device may also correspond to a Mobile Terminal (MT) portion of an Integrated Access and Backhaul (IAB) node (also known as a relay node). In the following description, the terms "terminal device", "communication device", "terminal", "user equipment" and "UE" may be used interchangeably.

In a Frequency Division Duplex (FDD) system, full UL/DL channel reciprocity cannot be assumed due to the duplex distance between UL and DL channels. However, partial channel reciprocity may be limited by the angle of departure (AoD) or angle of arrival (AoA) and the delay of the propagation multipath. Considering the UL/DL partial reciprocity attribute, the network device estimates the UL SRS to obtain delay related information, e.g., FD component, which may be the same as the terminal device's selection by DL CSI-RS. Therefore, the terminal device does not need to report the index of the selected FD component to save the payload.

On the other hand, in some cases, due to a large frequency duplex distance or limited UL SRS resources or SRS estimation error, etc., the selection of FD components may not be aligned for the network device and terminal device sides, which has an effect on CSI quantization accuracy and system performance. Thus, how the network device and the terminal device select FD components consistently can be a challenge.

The FD component selected typically fluctuates over time, so the network device needs to quickly inform the terminal device, in whole or in part, of the number of reciprocity-based. In some conventional solutions, the dynamic indication may be conveyed by some means, such as medium access control element (MAC-CE) or Downlink Control Information (DCI) signaling. However, they have to expend some signaling overhead in DL transmissions.

To address the above and other potential problems, embodiments of the present disclosure provide an improved solution. In this solution, the selected FD component is transmitted and indicated using RS resources. In this way, a low overhead solution that dynamically indicates FD component selection may be provided. The principles and implementations of the present disclosure are described in detail below with reference to the drawings.

Fig. 1 illustrates an example communication network 100 in which embodiments of the present disclosure may be implemented. As shown in fig. 1, the network 100 includes a first device 110 and a second device 120 served by the first device 110. It should be understood that the number of first and second devices shown in fig. 1 is for illustration purposes only and does not imply any limitation. Network 100 may include any suitable number of first and second devices suitable for implementing embodiments of the present disclosure. In some embodiments, the first device 110 may be a network device and the second device 120 may be a terminal device.

For purposes of illustration only and without limiting the scope of the present disclosure, some embodiments will be described in the context of the first device 110 being a network device and the second device 120 being a terminal device. It should be appreciated that in other embodiments, the first device 110 may be a terminal device and the second device 120 may be a network device. In other words, the principles and spirit of the present disclosure may be applied to uplink and downlink transmissions.

As shown in fig. 1, the first device 110 and the second device 120 may communicate with each other. The first device 110 may have multiple antennas for communicating with the second device 120. The second device 120 may also have multiple antennas for communicating with the first device 110. It should be appreciated that each of the first device 110 and the second device 120 may provide any suitable number of antennas suitable for implementing embodiments of the present disclosure.

Communications in network 100 may conform to any suitable standard including, but not limited to, LTE-evolution, LTE-advanced (LTE-a), wideband Code Division Multiple Access (WCDMA), code Division Multiple Access (CDMA), global system for mobile communications (GSM), and the like. Further, the communication may be performed according to any generation communication protocol currently known or to be developed in the future. Examples of communication protocols include, but are not limited to, first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, fifth generation (5G) communication protocols.

In some scenarios, the first device 110 may receive SRS from the second device 120 on PRBs in the SB and transmit CSI-R to the second device 120 on the PRBs. Fig. 2 illustrates a diagram of RS transmissions on PRBs in an SB according to some embodiments of the present disclosure. As shown in fig. 2, it is assumed that there are N3 SBs denoted as SB 0 to SB N3-1, and each SB includes M0 PRBs denoted as PRB 1 to PRB M0. Here, N3 and M0 may be any suitable integer.

Embodiments of the present disclosure provide a codebook design and mapping method that indicates to the second device 120 the exact FD component selected by the first device 110 for at least one data stream (also referred to herein as at least one layer) through the RS resources of beamforming. In some embodiments, each SB may be represented as an index of different FD components, where a total of N3 orthogonal FD components are assumed without oversampling, where N3 is the number of SBs. In each SB, one or more codebooks may be transmitted on one or more PRBs to indicate whether to select an FD component indexed by an SB number for at least one layer. It is assumed that the Rank Indicator (RI) has a longer feedback period than other CSI items, and thus the first device 110 has the same layer number knowledge as the second device 120 side. This mechanism of the present disclosure is shown in the high-level flow chart shown in fig. 3.

Fig. 3 shows a flow chart illustrating a communication process 300 according to some embodiments of the present disclosure. For convenience, fig. 3 will be described in connection with the examples of fig. 1 and 2. Process 300 may be performed for each SB, and thus will be described with respect to one SB.

As shown in fig. 3, first device 110 may generate 301 a configuration (also referred to herein as a first configuration) that indicates a mapping between one or more candidate content of FD component information (also referred to herein as first information) and one or more corresponding codebooks. The first information indicates whether FD components associated with SBs (e.g., SB 0 through N3-1 in fig. 2) are selected for at least one data stream. In some embodiments, the first configuration may be in the form of table 1 below.

Table 1 example codebook designs for different layers

Where RI value may represent the number of layers or data streams and P may represent the number of beamformed CSI-RS ports.

For example, in case there is only one data stream, i.e., ri=1, the candidate contents of the first information may include 0 and 1, and the corresponding codebook may be V ¹ (: 1) and V ¹ (:,2). For example, "0" may represent that FD components associated with an SB are not selected for the data flow, while "1" may represent that FD components associated with an SB are selected for the data flow. Similar definitions apply for multiple data streams.

It should be understood that the form of the first configuration in table 1 is merely an example and does not limit the present disclosure. Any other suitable form is also possible. The candidate content of the first information may also take any other suitable form. Furthermore, the codebook may be designed in any suitable form.

The first device 110 may also generate 301 a configuration (also referred to as a second configuration) indicating whether each PRB is to carry a codebook. In some embodiments, the second configuration may be in the form of a bit string. The bit string is used to indicate the codebook configuration position on the RS resource in all PRBs of the SB, assuming that all SBs of the entire bandwidth have the same configuration. Of course, the bit string is only one example, and any other suitable way is possible for the second configuration. The second configuration may be generated in various mapping forms. This will be described in detail with reference to fig. 4-10.

In some embodiments, multiple codebooks are transmitted over multiple PRBs to indicate FD components selected for at least one layer. Fig. 4 illustrates a diagram of an example bit string configuration 400, according to some embodiments of the present disclosure. As shown in fig. 4, "1" may be represented by a codebook indicating whether to select an FD component for the first layer, "2" may be represented by a codebook indicating whether to select an FD component for the second layer, and "0" may represent a configuration without a codebook. Naturally, if a bit string is used to indicate more layers, e.g., up to 4 layers, each box of fig. 4 may contain 3 bits (also referred to herein as a sequence) to indicate no configuration, first layer, second layer, third layer, or fourth layer. In this case, the total length of the bit string is 3M0, where M0 is the number of consecutive PRBs within the SB.

In some embodiments, a codebook may be configured on a plurality of beamformed CSI-RS ports within a PRB, and its length may be the number P of beamformed CSI-RS ports. For example codebook V ¹ (: 1) and V ¹ (: 2) may be formed of 2 of the P orthogonal DFT vectors, one vector being represented as the FD component of the layer selection (e.g., V ¹ (: 1)) while the other vector represents an FD component that is not selected for a layer (e.g., V ¹ (:,2)). Each codebook has dimensions of P x 1.

In some alternative embodiments, a single codebook may be transmitted on one PRB to indicate the FD component selected for at least one layer. Fig. 5 illustrates a diagram of an example bit string configuration 500, according to some embodiments of the present disclosure. As shown in fig. 5, "1" may be represented by a codebook indicating whether or not to select an FD component for at least one layer, and "0" may represent a configuration without a codebook. In this case, the total length of the bit string is M0, where M0 is the number of consecutive PRBs within the SB.

In these embodiments, the design of the codebook may depend on the number of layers (i.e., RI values) shown in table 1. For example, when ri=1, there are 2 codebooks V ¹ (: 1) and V ¹ (:,2). For ri=r, there is 2 ^r Codebook V ^r (r=1, 2, …). Codebook V ^r Indicating whether the FD component indexed by SB number is selected in each layer when ri=r. For example, "1" may indicate that the FD component is selected, and "0" may indicate that the FD component is not selected. For example, when ri=3, V ³ (1) denotes that FD component is not selected for all 3 layers, V ³ (: 4) represents FD component not selected for the first layer but selected for the other 2 layers. The codebook may be formed from DFT vectors having the dimension P x P or an over-sampled or under-sampled version thereof.

Additionally, the bit string configurations in fig. 4 and 5 may be used in combination. In some embodiments, instead of transmitting all the first information on one PRB, the first information may be distributed over several PRBs. Each PRB carries first information for a subset of layers. For example, PRB 0 carries mapping information of

layers

1 and 2, while PRB #n carries mapping information of layers 3 and 4. Therefore, even if the maximum rank is 4, columns associated with ri=2 will actually be considered. This approach will have the advantage of better robustness against pilot pollution effects, since the first information is distributed over several PRBs and the number of entries in table 1 can be effectively reduced, thus the complexity required to find the sequence at the second device side can be reduced. If M ₅ The layers are mapped together, then only

Entries other than 2 in Table 1 are required ^RI An entry. For example, at ri=4 and M ₅ In the case of =2, instead of 16 entries, the second device 120 would only have to look within 8 entries.

In practice, channel estimation noise may negatively affect the detection of the bit string on the second device 120 side due to pilot pollution. To address this problem, in some embodiments, the bit strings may be repeated over the PRBs. In some embodiments, the bit strings may be repeated on adjacent PRBs. Fig. 6 illustrates a diagram of an example bit string configuration 600, according to some embodiments of the present disclosure. For example, for the bit string shown in fig. 4, it may be repeated as shown in fig. 6. Fig. 7 illustrates a diagram of an example bit string configuration 700, according to some embodiments of the present disclosure. For example, for the bit string shown in fig. 5, it may be repeated as shown in fig. 7.

In some embodiments, the bit strings may be repeated on non-adjacent PRBs. Fig. 8 illustrates a diagram of an example bit string configuration 800, according to some embodiments of the present disclosure. For example, for the bit string shown in fig. 4, it may be repeated as shown in fig. 8. Fig. 9 illustrates a diagram of an example bit string configuration 900, according to some embodiments of the present disclosure. For example, for the bit string shown in fig. 5, it may be repeated as shown in fig. 9.

In some embodiments, some similarity may be observed in the FD component of adjacent layers, in which case the attribute may be utilized, where a sequence may be mapped to M ₅ And more than or equal to 1 layer. In other words, if a sequence is detected, the FD component corresponding to the SB index will be active in all mapped layers. This is referred to herein as layer grouping. For example, for a bit string as shown in fig. 4, it is assumed that sequence 1 is mapped to

layers

1 and 2 and sequence 2 is mapped to layers 3 and 4 in 2 PRBs, respectively. The advantage here is that only 2 entries in table 1 are used to indicate the first information required for the 2 layers of each PRB, instead of 4 entries.

In some embodiments, the application layer packet will have a factor that reduces the number of entries in Table 1 over the bit string shown in FIG. 5

Has the advantages of (a). For example, at ri=4 and M ₅ In the case of =2, layers 1 and 2 are grouped together, while layers 3 and 4 are grouped together. Thus, instead of 16 entries in table 1, only 4 entries are needed. Note that the proposed layer grouping is different from the combination of the bit string configurations in fig. 4 and 5 described above. In the proposed layer grouping, it is assumed that several layers will have the same FD base subset W _f . However, in the above-described combination of bit string configurations in fig. 4 and 5, such an approximation assumption is not made.

It should be noted that the mapping forms shown in fig. 4-10 are merely examples, and that the second configuration may also be generated in any suitable mapping form. Furthermore, it should be appreciated that the codebook design in the first configuration may be associated with the mapping form of the second configuration.

Returning to fig. 3, the first device 110 may send 302 the first and second configurations to the second device 120. In some embodiments, the first device 110 may send the first and second configurations in higher layer signaling, such as RRC signaling. Of course, any other suitable means are also possible. In some embodiments, the first and second configurations may be sent in the same signaling. In some alternative embodiments, the first and second configurations may be sent in different signaling.

In some embodiments, the first device 110 may also generate and send an indication (also referred to herein as a first indication) indicating that the RS to be sent by the first device 110 carries the first information. In other words, the first indication may indicate an RS (e.g., CSI-RS) operation mode in which a particular codebook is transmitted.

In some embodiments, the first device 110 may also generate and send an indication (also referred to herein as a second indication) indicating a form of mapping for the second configuration. For example, the second indication may indicate one of the bit string configurations shown in fig. 4-9.

Referring to fig. 3, the second device 120 transmits 303 RSs (also referred to herein as a first plurality of RSs) to the first device 110 as needed. For example, the second device 120 may transmit an uplink SRS to the first device 110. Of course, any other suitable RS is also possible.

Upon receiving the first plurality of RSs, the first device 110 determines 304 first information regarding whether to select FD components associated with the sub-bands for the at least one data stream. For example, the first device 110 may detect an uplink channel matrix from the uplink SRS from the second device 120 and determine a set of M most significant FD components for each layer. The first device 110 may determine the first information based on a set of M most significant FD components. For example, for ri=3, as shown in table 1, the first information of layers 1 to 3 may be 000. This is merely an example and does not limit the present disclosure.

After determining the first information, the first device 110 determines 305 at least one codebook for the first information based on the first configuration. For example, the first device 110 may select the corresponding codebook by looking up table 1. As shown in table 1, if the first information is 000 for layers 1 to 3 of ri=3, the corresponding codebook is determined to be V ³ (:,1). It should be appreciated that the determined codebook may be more codebooks depending on the form of the mapping of the second configuration.

In some embodiments, a single codebook may be designed for at least one data stream. In these embodiments, the first device 110 may determine a single codebook from the codebooks in the first configuration.

In some embodiments, multiple codebooks may be designed for at least one data stream. For convenience, the following description is made taking two codebooks as an example. In this case, the at least one data stream may comprise a first set of data streams and a second set of data streams. The first set of data streams may include one or more data streams and the second set of data streams may include one or more other data streams. In this case, the first configuration may include a first set of codebooks for the first set of data streams and a second set of codebooks for the second set of data streams. In some embodiments, the first set of codebooks may include one or more sets of codebooks for one or more respective data streams. In some embodiments, for example in the case of layer packets, the first set of codebooks may include only one set of codebooks for one or more respective data streams. In these embodiments, the first device 110 may determine two codebooks from the first and second sets of codebooks in the first configuration.

After determining the at least one codebook, the first device 110 transmits 306 an RS (also referred to herein as a second plurality of RSs) having the at least one codebook to the second device 120. For example, the first device 110 may transmit CSI-RS to the second device 120. Of course, any other suitable RS is also possible. In some embodiments, first device 110 may determine a portion of PRBs in the SB that is to carry at least one codebook thereon based on the second configuration. Thus, the first device 110 may transmit a subset of the second plurality of RSs on the portion of PRBs and other RSs without codebook on other PRBs.

In some embodiments, a single codebook may be designed for at least one data stream. In these embodiments, the first device 110 may determine one or more PRBs (also referred to herein as a first PRB set) from the second configuration, on which to carry a single codebook. For example, if the mapping form of the second configuration is the mapping form in fig. 5, the first device 110 may determine one PRB (i.e., PRB 0) to carry a single codebook. As another example, if the mapping form of the second configuration is the mapping form in fig. 7 or 9, the first device 110 may determine that both PRBs (i.e., PRB 0 and PRB 1) carry a single codebook. It is to be understood that the description is intended to be illustrative, and not restrictive.

In some embodiments, multiple codebooks may be designed for at least one data stream. In these embodiments, the first device 110 may determine, from the second configuration, a plurality of PRB sets on which to carry a plurality of codebooks, respectively. For example, the first device 110 may determine one PRB set (also referred to herein as a second PRB set) on which to carry one codebook (also referred to herein as a first codebook) of the plurality of codebooks and another PRB set (also referred to herein as a third PRB set) on which to carry another codebook of the plurality of codebooks.

As an example, if the mapping form of the second configuration is one of the mapping forms in fig. 4, 6 and 8, the first device 110 may determine a plurality of PRB sets (i.e., PRB 0) to carry a plurality of codebooks. Of course, multiple codebooks may be applied in combination with layer packets as described above. It is to be understood that the description is intended to be illustrative, and not restrictive.

Fig. 10 illustrates a diagram 1000 of transmission of a codebook on a beamformed CSI-RS in accordance with some embodiments of the present disclosure. As shown in fig. 10, for the ith SB, codebook vectors are configured in the first PRB spanning P CSI-RS ports

Wherein the method comprises the steps ofi=0, …, N3-1. Codebook vector +.>

Is one of the codebooks from the first configuration and indicates whether the ith FD component is selected for one or more layers depending on the mapping form of the second configuration. In fig. 11, reference numeral 1010 denotes 2×cdm for csi=rs ports 2 and 3, and reference numeral 1020 denotes 2×cdm for csi=

rs ports

0 and 1. In some embodiments, vector +.>

Is (such as->

Is transmitted in the jth beamformed CSI-RS port occupying 2 consecutive Resource Elements (REs). Thus, a complete signature codebook is sent on all beamformed CSI-RS ports in the first PRB of the ith SB>

In some embodiments, different codebooks may be configured in different SB's. Of course, codebooks of the same design may be configured in different SBs.

Referring to fig. 3, upon receiving the second plurality of RSs in all PRBs in the SB, the second device 120 determines 307 the first information from the second plurality of RSs. In some embodiments, the second device 120 may determine the first information upon receiving the first indication from the first device 110. In some embodiments, the second device 120 may determine a mapped version of the second configuration based on the second indication from the first device 110, and then determine the first information based on the first and second configurations. For example, the second device 120 may search for and estimate which codebooks have been applied according to the first and second configurations.

In some embodiments, a single codebook may be designed for at least one data stream, for example, in the case where the mapping form of the second configuration may be one of the mapping forms in fig. 5, 7, and 9. In these embodiments, the second device 120 may determine a set of PRBs (e.g., a first set of PRBs) on which to carry a single codebook and a set of PRBs (also referred to herein as a fourth set of PRBs) on which to not carry a single codebook. The second device 120 may then determine a single codebook based on the codebook in the first configuration and channel information in the first and fourth PRB sets, and determine first information corresponding to the single codebook based on the first configuration.

In some embodiments, the first set of PRBs and the fourth set of PRBs may be contiguous. Of course, any other suitable means are also possible.

In some embodiments, multiple codebooks may be designed for at least one data stream, for example, in the case where the mapping form of the second configuration may be one of the mapping forms along or in combination with layer packets in fig. 4, 6 and 8. In these embodiments, the second device 120 may determine a set of PRBs on which to carry the first codebook (e.g., a second set of PRBs) and a set of PRBs on which to carry the second codebook (e.g., a third set of PRBs), and also determine a set of PRBs on which to not carry the first or second codebook (also referred to herein as a fifth set of PRBs). The second device 120 may then determine the first codebook based on the channel information in the first codebook set and the second and fifth PRB sets, and determine the second codebook based on the channel information in the second codebook set and the third and fifth PRB sets. In this way, the second device 120 may determine the first information from the first configuration based on the first and second codebooks.

In some embodiments, the second set of PRBs and the fifth set of PRBs may be contiguous. In some embodiments, the third set of PRBs and the fifth set of PRBs may be contiguous. Of course, any other suitable means are also possible.

For illustration, the decoding process will be described in more detail on the assumption that the mapping form of the second configuration is the mapping form in fig. 5, i.e., the codebook is mapped to a single PRB of each SB.

In some embodiments, second device 120 may select the first two consecutive PRBs in each SB, one of which contains a codebook, assuming ri=r, (r=1, 2, …). For the ith SB, codebook directionMeasuring amount

Is configured in the first PRB spanning P CSI-RS ports, and is V in Table 1 ^r Is defined in the row vector. Therefore, the equivalent channel matrix H, for example, expression (1), may be acquired in the first PRB.

Wherein H is ₁ Having dimension N _rx X P, and N _rx Is the number of receive antenna ports.

No codebook is configured in the second PRB, thus obtaining a physical channel matrix, e.g. H ₂ Having dimension N _rx X P. It is assumed that the channel estimation on a given CSI-RS port does not vary much for two consecutive PRBs, so the channel matrix is very similar for two PRBs. Then, the following expression (2) can be obtained:

H ₁ ≈H ₂ (2)

Let w be ₁ And w ₂ Respectively, a normalized version of the channel matrix, e.g., as shown in expressions (3) and (4):

then, the following expression (5) can be obtained:

w ₁ ≈w ₂ (5)

after normalization, the equivalent channel matrix H may be transformed in the first PRB as shown in expression (6):

in another embodiment, w ₁ And w ₂ May be set as a channel vector in the receiving port or as a eigenvector of the channel matrix.

The second device 120 may be from codebook V ^r And find the exact codebook used by the first device 110 from the decoding metric a of each pair of channel matrices in the two PRBs of the i-th subband. The decoding metric a is shown in expression (7):

wherein V is ^r (: m) is a signature codebook V with a norm 1 ^r M e {1,2, …,2r }.

If it is

A=1, which is the maximum value of a. Otherwise A < 1. If a=1, the corresponding codebook is exactly that indicated by the first device 110 on the RS. Next, the second device 120 detects all codebooks one by one in all the subbands N3. The original channel matrix may be recovered by using appropriate decoding. For example, when->

When the following expression (8) is obtained:

it should be noted that the above described decoding process is only an example and that any other suitable way is also possible.

The second device 120 may then transform all detected codebooks into corresponding FD components for the multiple layers according to the first configuration. Thus, the second device 120 may detect all M FD components indicated by the first device 110 for each layer. I.e. the first information is determined.

Based on the first information, the second device 120 sends 308 CSI to the first device 110. In some embodiments, the second device 120 may multiply the DL channel matrix by the FD component for FD transformation and calculate a Linear Combination (LC) coefficient. The second device 120 may then report the CSI item related to the LC coefficient to the first device 110. In this case, the FD component selection need not be reported. Thus, the first device 110 may reconstruct 309 the channel matrix from the SRS measurements and the CSI reports from the second device 120.

Through the procedure described in fig. 3, FD component selection of the first device 110 may be indicated to the second device 120 by means of an RS with a certain codebook. In this way, FD component selection may be dynamically indicated from the first device to the second device with low overhead.

Corresponding to the above procedure, some example embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. However, those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is for explanatory purposes as the invention extends beyond these limited embodiments.

Fig. 11 illustrates a flow chart of a communication method 1100 implemented at a first device according to an example embodiment of the disclosure. The method 1100 may be implemented at the first device 110 shown in fig. 1. For discussion purposes, the method 1100 will be described with reference to FIG. 1. It is to be appreciated that method 1100 may also include additional blocks not illustrated and/or blocks not illustrated, and that the scope of the present disclosure is not limited in this respect.

As shown in fig. 11, in block 1110, the first device 110 receives a first plurality of RSs from the second device 120 on PRBs in the SB. In block 1120, in response to receiving the first plurality of RSs, first device 110 determines first information regarding whether to select an FD component associated with the SB for at least one data flow.

In block 1130, the first device 110 determines at least one codebook for the first information based on a first configuration, the first configuration indicating a mapping between one or more candidate content of the first information and one or more corresponding codebooks.

In some embodiments, in which at least one codebook comprises a single codebook for at least one data stream, the first device 110 may determine the single codebook from one or more corresponding codebooks in the first configuration.

In some embodiments in which the at least one data stream comprises a first set of data streams and a second set of data streams, and the at least one codebook comprises a first codebook for the first set of data streams and a second codebook for the second set of data streams, and the first configuration comprises the first set of data streams and the second set of data streams, the first device 110 may determine the first codebook from the first set of codebooks and the second codebook from the second set of codebooks.

In block 1140, the first device 110 transmits a subset of the second plurality of RSs with the at least one codebook to the second device 120 on a portion of PRBs determined from a second configuration indicating whether the PRBs are to carry the at least one codebook.

In some embodiments in which the at least one codebook comprises a single codebook for the at least one data stream, the first device 110 may determine from the second configuration a first set of PRBs on which to carry the single codebook. The first device 110 may then transmit a subset of the second plurality of RSs with the single codebook on the first set of PRBs; and transmitting other RSs of the second plurality of RSs, except for the subset, on other ones of the PRBs, except for the first set of PRBs.

In some embodiments in which the at least one data stream includes a first set of data streams and a second set of data streams, and the at least one codebook includes a first codebook for the first set of data streams and a second codebook for the second set of data streams, and the first configuration includes the first set of codebooks for the first set of data streams and the second set of codebooks for the second set of data streams, the first device 110 may determine a second set of PRBs on which the first codebook is carried, and a third set of PRBs on which the second codebook is carried, of the PRBs, according to the second configuration. The first device 110 may then transmit a first portion of the subset of the second plurality of RSs with the first codebook on the second set of PRBs, transmit a second portion of the subset of the second plurality of RSs with the second codebook on the third set of PRBs, and transmit other RSs of the second plurality of RSs except for the first and second portions on other ones of the PRBs except for the second and third sets of PRBs.

In some embodiments, the first device 110 may generate the first and second configurations and send the first and second configurations to the second device 120.

In some embodiments, the first device 110 may also generate a first indication that indicates that the second plurality of RSs carry the first information and send the first indication to the second device 120.

In some embodiments, the first device 110 may also generate a second indication indicating a form of mapping to be used for the second configuration and send the second indication to the second device 120.

The operations in the method of fig. 12 correspond to the operations in the process described in fig. 3, and thus other details are omitted here for brevity. With the method of fig. 11, FD component selection can be dynamically indicated from the first device to the second device with low overhead.

Accordingly, embodiments of the present disclosure also provide a communication method implemented at a second device. Fig. 12 illustrates a flowchart of a communication method 1200 implemented at a second device according to an example embodiment of the disclosure. The method 1200 may be implemented at the second device 120 shown in fig. 1. For discussion purposes, the method 1200 will be described with reference to fig. 1. It should be understood that method 1200 may also include additional blocks not shown and/or blocks that are omitted from some of the illustrations, and the scope of this disclosure is not limited in this respect.

As shown in fig. 12, in block 1210, the second device 120 receives a second plurality of RSs from the first device 110 on PRBs in the SB. In some embodiments, the second device 120 may receive the first and second configurations from the first device 110. In some embodiments, the second device 120 may also receive a first indication indicating that the second plurality of RSs carry the first information. In some embodiments, the second device 120 may also receive a second indication indicating a form of mapping to be used for the second configuration.

In block 1220, second device 120 determines first information regarding whether to select FD components associated with the SB for the at least one data stream based on the first and second configurations, the first configuration indicating a mapping between one or more candidate content of the first information and one or more corresponding codebooks, and the second configuration indicating whether the PRB is to carry the at least one codebook.

In some embodiments in which the at least one codebook comprises a single codebook for the at least one data stream, the second device 120 may determine a first set of PRBs on which the single codebook is carried, and a fourth set of PRBs on which the single codebook is not carried, of the PRBs, based on the second configuration. The second device 120 may then determine a single codebook based on the one or more respective codebooks and the channel information in the first and fourth PRB sets, and determine first information corresponding to the single codebook based on the first configuration.

In some embodiments, where the at least one data stream includes a first data stream set and a second data stream set, and the at least one codebook includes a first codebook for the first data stream set and a second codebook for the second data stream set, and the first configuration includes the first codebook set for the first data stream set and the second codebook set for the second data stream set, the second device 120 may determine, based on the second configuration, a second set of PRBs on which the first codebook is carried, a third set of PRBs on which the second codebook is carried, and a fifth set of PRBs on which the first or second codebook is not carried. The second device 120 may then determine a first codebook based on the channel information in the first codebook set and the second and fifth PRB sets, determine a second codebook based on the second group codebook and the channel information in the third and fifth PRB sets, and determine the first information from the first configuration based on the first and second codebooks.

In block 1230, the second device 120 transmits CSI to the first device 110 based on the first information.

The operations in the method of fig. 12 correspond to the operations in the process described in fig. 3, and thus other details are omitted here for brevity. With the method of fig. 12, FD component selections may be dynamically decoded by the second device in the RS from the first device without indicating FD component selections to the first device. In this way, a reduced complexity of the second device may be achieved.

In some embodiments, an apparatus (e.g., first device 110) capable of performing method 1100 may include means for performing the various steps of method 1100. The apparatus may be implemented in any suitable form. For example, the apparatus may be implemented in a circuit or a software module.

In some embodiments, the apparatus may include: means for determining, at the first device, first information regarding whether to select a frequency domain component associated with the subband for the at least one data stream in response to receiving a first plurality of reference signals from the second device over physical resource blocks in the subband; means for determining at least one codebook for the first information based on a first configuration, the first configuration indicating a mapping between one or more candidate content of the first information and one or more corresponding codebooks; and means for transmitting a subset of the second plurality of reference signals having the at least one codebook to the second device on a portion of the physical resource blocks determined from a second configuration indicating whether the physical resource blocks are to carry the at least one codebook.

In some embodiments, the apparatus may further comprise: means for generating a first and a second configuration; and means for transmitting the first and second configurations to the second device.

In some embodiments, the apparatus may further comprise: means for generating a first indication indicating that the second plurality of reference signals carry the first information; and means for sending the first indication to the second device.

In some embodiments, the apparatus may further comprise: means for generating a second indication indicating a form of mapping to be used for a second configuration; and means for sending a second indication to the second device.

In some embodiments, the at least one codebook may comprise a single codebook for at least one data stream. In these embodiments, the means for determining at least one codebook may comprise means for determining a single codebook from one or more corresponding codebooks. In these embodiments, the means for transmitting a subset of the second plurality of reference signals may comprise: determining, from the second configuration, a first set of physical resource blocks of the physical resource blocks on which to carry a single codebook; means for transmitting a subset of the second plurality of reference signals having a single codebook on the first set of physical resource blocks; and means for transmitting other reference signals than the subset of the second plurality of reference signals on other ones of the physical resource blocks than the first set of physical resource blocks.

In some embodiments, the at least one data stream may include a first set of data streams and a second set of data streams, and the at least one codebook may include a first codebook for the first set of data streams and a second codebook for the second set of data streams, and the first configuration may include the first set of codebooks for the first set of data streams and the second set of codebooks for the second set of data streams. In these embodiments, the means for determining at least one codebook may comprise: means for determining a first codebook from a first set of codebooks; and means for determining a second codebook from the second set of codebooks.

In these embodiments, the means for transmitting a subset of the second plurality of reference signals may comprise: determining, from the second configuration, a second set of physical resource blocks of the physical resource blocks on which to carry the first codebook, and a third set of physical resource blocks of the physical resource blocks on which to carry the second codebook; means for transmitting a first portion of a subset of the second plurality of reference signals having the first codebook on the second set of physical resource blocks; means for transmitting a second portion of the subset of the second plurality of reference signals having the second codebook on a third set of physical resource blocks; and means for transmitting other reference signals than the first and second portions of the second plurality of reference signals on other ones of the physical resource blocks than the second and third sets of physical resource blocks.

In some embodiments, an apparatus (e.g., second device 120) capable of performing method 1200 may include means for performing the respective steps of method 1200. The component may be implemented in any suitable form. For example, the components may be implemented in circuitry or software modules.

In some embodiments, the apparatus may include: means for receiving, at the first device, a second plurality of reference signals from the first device on physical resource blocks in a subband; means for determining first information regarding whether to select a frequency domain component associated with a subband for at least one data stream based on first and second configurations, the first configuration indicating a mapping between one or more candidate content of the first information and one or more corresponding codebooks, and the second configuration indicating whether a physical resource block is to carry at least one codebook; and means for transmitting channel state information to the first device based on the first information.

In some embodiments, the apparatus may further comprise: means for receiving the first and second configurations from the first device.

In some embodiments, the apparatus may further comprise: means for receiving a first indication indicating that the second plurality of reference signals carry the first information. In these embodiments, the means for determining the first information may comprise means for determining the first information upon receipt of the first indication.

In some embodiments, the apparatus may further comprise: means for receiving a second indication indicating a form of mapping to be used for the second configuration. In these embodiments, the means for determining the first information may include means for determining the first information based on the first and second configurations when the second indication is received.

In some embodiments, the at least one codebook may comprise a single codebook for at least one data stream. In these embodiments, the means for determining the first information may include: means for determining, based on the second configuration, a first set of physical resource blocks of the physical resource blocks on which the single codebook is carried, and a fourth set of physical resource blocks of the physical resource blocks on which the single codebook is not carried; means for determining a single codebook based on one or more respective codebooks and channel information in the first and fourth sets of physical resource blocks; and means for determining first information corresponding to the single codebook based on the first configuration.

In some embodiments, the at least one data stream may include a first set of data streams and a second set of data streams, and the at least one codebook includes a first codebook for the first set of data streams and a second codebook for the second set of data streams, and the first configuration includes the first set of codebooks for the first set of data streams and the second set of codebooks for the second set of data streams.

In these embodiments, the means for determining the first information may include: means for determining, based on the second configuration, a second set of physical resource blocks of the physical resource blocks on which the first codebook is to be carried, a third set of physical resource blocks of the physical resource blocks on which the second codebook is to be carried, and a fifth set of physical resource blocks of the physical resource blocks on which the first or second codebook is not to be carried; means for determining a first codebook based on the first set of codebooks and channel information in the second and fifth sets of physical resource blocks; means for determining a second codebook based on the second set of codebooks and channel information in the third and fifth sets of physical resource blocks; and means for determining the first information from the first configuration based on the first and second codebooks.

Fig. 13 is a simplified block diagram of a device 1300 suitable for implementing embodiments of the present disclosure. The device 1300 may be provided to implement a first device or a second device, such as the first device 110 or the second device 120 shown in fig. 1. As shown, the device 1300 includes one or more processors 1310, one or more memories 1320 coupled to the processors 1310, and one or more communication modules 1340 (e.g., a transmitter and/or a receiver) coupled to the processors 1310.

The communication module 1340 is used for two-way communication. The communication module 1340 has at least one antenna to facilitate communication. The communication interface may represent any interface required to communicate with other network elements.

As non-limiting examples, the processor 1310 may be of any type suitable for a local technology network and may include one or more of the following: general purpose computers, special purpose computers, microprocessors, digital Signal Processors (DSPs), and processors based on a multi-core processor architecture. The device 1400 may have multiple processors, such as application specific integrated circuit chips that are temporally slaved to a clock that synchronizes the master processor.

Memory 1320 may include one or more non-volatile memories and one or more volatile memories. Examples of non-volatile memory include, but are not limited to, read-only memory (ROM) 1324, electrically programmable read-only memory (EPROM), flash memory, a hard disk, a Compact Disk (CD), a Digital Video Disk (DVD), and other magnetic and/or optical memory. Examples of volatile memory include, but are not limited to, random Access Memory (RAM) 1322 and other volatile memory that does not last for the duration of the power outage.

The computer program 1330 includes computer-executable instructions that are executed by an associated processor 1310. Program 1330 may be stored in ROM 1324. Processor 1310 may perform any suitable actions and processes by loading program 1330 into RAM 1322.

Embodiments of the present disclosure may be implemented by means of program 1330 such that device 1300 may perform any of the processes of the present disclosure as discussed with reference to fig. 1-12. Embodiments of the present disclosure may also be implemented in hardware or a combination of software and hardware.

In some embodiments, program 1330 may be tangibly embodied in a computer-readable medium, which may be included in device 1300 (e.g., in memory 1320) or other storage device accessible by device 1300. The device 1300 may load the program 1330 from a computer readable medium into RAM 1322 for execution. The computer readable medium may include any type of tangible, non-volatile memory, such as ROM, EPROM, flash memory, hard disk, CD, DVD, etc. Fig. 14 shows an example of a computer readable medium 1400 in the form of a CD or DVD. The computer readable medium has stored thereon a program 1330.

In general, the various embodiments of the disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While aspects of the embodiments of the disclosure are illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, that are executed in a device on a target real or virtual processor to perform the

methods

1100 and 1200 as described above with reference to fig. 11 and 12. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or separated as desired in various embodiments. Machine-executable instructions of program modules may be executed within local or distributed devices. In distributed devices, program modules may be located in both local and remote memory storage media.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program code may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus such that the program code, when executed by the processor or controller, causes the functions/operations specified in the flowchart and/or block diagram to be implemented. The program code may execute entirely on the machine, partly on the machine, as a stand-alone software package, partly on the machine, partly on a remote machine or entirely on the remote machine or server.

In the context of this disclosure, computer program code or related data may be carried by any suitable carrier to enable an apparatus, device or processor to perform the various processes and operations as described above. Examples of carrier waves include signals, computer readable media, and the like.

The computer readable medium may be a computer readable signal medium or a computer readable storage medium. The computer readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of a computer-readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Moreover, although operations are described in a particular order, this should not be construed as requiring that these operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In some cases, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are included in the above discussion, these details should not be construed as limitations on the scope of the disclosure, but rather as descriptions of features specific to particular embodiments. Certain features that are described in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination.

Although the disclosure has been described in language specific to structural features and/or methodological acts, it is to be understood that the disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

1. A first device, comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code are configured to, with the at least one processor, cause the first device to:

responsive to receiving a first plurality of reference signals from a second device on physical resource blocks in a subband, determining first information regarding whether a frequency domain component associated with the subband is selected for at least one data stream;

determining at least one codebook for the first information based on a first configuration, the first configuration indicating a mapping between one or more candidate content of the first information and one or more corresponding codebooks; and

transmitting, to the second device, a subset of a second plurality of reference signals having the at least one codebook on a portion of the physical resource blocks, the portion of the physical resource blocks determined according to a second configuration indicating whether the at least one codebook is to be carried for the physical resource blocks.

2. The first device of claim 1, wherein the first device is further caused to:

generating the first configuration and the second configuration; and

the first configuration and the second configuration are sent to the second device.

3. The first device of claim 1, wherein the first device is further caused to:

generating a first indication indicating that the second plurality of reference signals carry the first information; and

and sending the first indication to the second device.

4. The first device of claim 1, wherein the first device is further caused to:

generating a second indication indicating a form of mapping to be used for the second configuration; and

and sending the second indication to the second device.

5. The first device of claim 1, wherein the at least one codebook comprises a single codebook for the at least one data stream,

wherein the first device is caused to determine the at least one codebook by: determining the single codebook from the one or more corresponding codebooks, and

wherein the first device is caused to transmit the subset of the second plurality of reference signals by:

Determining a first set of physical resource blocks of the physical resource blocks on which to carry the single codebook according to the second configuration;

transmitting the subset of the second plurality of reference signals with the single codebook on the first set of physical resource blocks; and

and transmitting other reference signals except the subset in the second plurality of reference signals on other physical resource blocks except the first physical resource block set in the physical resource blocks.

6. The first device of claim 1, wherein the at least one data stream comprises a first set of data streams and a second set of data streams, and the at least one codebook comprises a first codebook for the first set of data streams and a second codebook for the second set of data streams, and the first configuration comprises a first set of codebooks for the first set of data streams and a second set of codebooks for the second set of data streams,

wherein the first device is caused to determine the at least one codebook by:

determining the first codebook from the first set of codebooks; and

determining the second codebook from the second set of codebooks, and

determining a second set of physical resource blocks of the physical resource blocks on which the first codebook is to be carried, and a third set of physical resource blocks of the physical resource blocks on which the second codebook is to be carried, according to the second configuration;

transmitting, on the second set of physical resource blocks, a first portion of the subset of the second plurality of reference signals having the first codebook;

transmitting, on the third set of physical resource blocks, a second portion of the subset of the second plurality of reference signals having the second codebook; and

and transmitting other reference signals except the first part and the second part in the second plurality of reference signals on other physical resource blocks except the second physical resource block set and the third physical resource block set in the physical resource blocks.

7. The first device of claim 1, wherein the first device is a network device and the second device is a terminal device.

8. A second device, comprising:

At least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code are configured to, with the at least one processor, cause the second device to:

receiving, on a physical resource block in a subband, a second plurality of reference signals from a first device;

determining first information regarding whether frequency domain components associated with the subbands are selected for at least one data stream based on a first configuration and a second configuration, the first configuration indicating a mapping between one or more candidate content of the first information and one or more corresponding codebooks, and the second configuration indicating whether at least one codebook is to be carried for the physical resource block; and

and transmitting channel state information to the first equipment based on the first information.

9. The second device of claim 8, wherein the second device is further caused to:

the first configuration and the second configuration are received from the first device.

10. The second device of claim 8, wherein the second device is further caused to: receiving a first indication that the second plurality of reference signals carry the first information, and

Wherein the second device is caused to: the first information is determined upon receipt of the first indication.

11. The second device of claim 8, wherein the second device is further caused to: receiving a second indication indicating a form of mapping to be used for the second configuration, and

wherein the second device is caused to: the first information is determined based on the first configuration and the second configuration, upon receipt of the second indication.

12. The second device of claim 8, wherein the at least one codebook comprises a single codebook for the at least one data stream,

wherein the second device is caused to determine the first information by:

determining, based on the second configuration, a first set of physical resource blocks of the physical resource blocks on which the single codebook is carried, and a fourth set of physical resource blocks of the physical resource blocks on which the single codebook is not carried;

determining the single codebook based on the one or more corresponding codebooks and channel information in the first set of physical resource blocks and the fourth set of physical resource blocks; and

based on the first configuration, the first information corresponding to the single codebook is determined.

13. The second device of claim 8, wherein the at least one data stream comprises a first set of data streams and a second set of data streams, and the at least one codebook comprises a first codebook for the first set of data streams and a second codebook for the second set of data streams, and the first configuration comprises a first set of codebooks for the first set of data streams and a second set of codebooks for the second set of data streams,

wherein the second device is caused to determine the first information by:

determining, based on the second configuration, a second set of physical resource blocks of the physical resource blocks on which the first codebook is carried, a third set of physical resource blocks of the physical resource blocks on which the second codebook is carried, and a fifth set of physical resource blocks of the physical resource blocks on which either the first codebook or the second codebook is not carried;

determining the first codebook based on the first codebook set and channel information in the second physical resource block set and the fifth physical resource block set;

determining the second codebook based on the second codebook set and channel information in the third and fifth physical resource block sets; and

The first information is determined according to the first configuration based on the first codebook and the second codebook.

14. The second device of claim 8, wherein the first device is a network device and the second device is a terminal device.

15. A method of communication, comprising:

responsive to receiving a first plurality of reference signals from a second device on physical resource blocks in a subband, determining, at the first device, first information regarding whether a frequency domain component associated with the subband is selected for at least one data stream;

16. The method of claim 15, further comprising:

Generating the first configuration and the second configuration; and

17. The method of claim 15, further comprising:

and sending the first indication to the second device.

18. The method of claim 15, further comprising:

and sending the second indication to the second device.

19. The method of claim 15, wherein the at least one codebook comprises a single codebook for the at least one data stream,

wherein determining the at least one codebook comprises: determining the single codebook from the one or more corresponding codebooks, and

wherein transmitting the subset of the second plurality of reference signals comprises:

20. The method of claim 15, wherein the at least one data stream comprises a first set of data streams and a second set of data streams, and the at least one codebook comprises a first codebook for the first set of data streams and a second codebook for the second set of data streams, and the first configuration comprises a first set of codebooks for the first set of data streams and a second set of codebooks for the second set of data streams,

wherein determining the at least one codebook comprises:

determining the first codebook from the first set of codebooks; and

determining the second codebook from the second set of codebooks, and

21. The method of claim 15, wherein the first device is a network device and the second device is a terminal device.

22. A method of communication, comprising:

at the second device, receiving, on physical resource blocks in the subband, a second plurality of reference signals from the first device;

23. The method of claim 22, further comprising:

24. The method of claim 22, further comprising:

receiving a first indication that the second plurality of reference signals carry the first information, and

wherein determining the first information comprises: the first information is determined upon receipt of the first indication.

25. The method of claim 22, further comprising:

receiving a second indication indicating a form of mapping to be used for the second configuration, and

wherein determining the first information comprises: the first information is determined based on the first configuration and the second configuration, upon receipt of the second indication.

26. The method of claim 22, wherein the at least one codebook comprises a single codebook for the at least one data stream,

wherein determining the first information comprises:

27. The method of claim 22, wherein the at least one data stream comprises a first set of data streams and a second set of data streams, and the at least one codebook comprises a first codebook for the first set of data streams and a second codebook for the second set of data streams, and the first configuration comprises a first set of codebooks for the first set of data streams and a second set of codebooks for the second set of data streams,

wherein determining the first information comprises:

28. The method of claim 22, wherein the first device is a network device and the second device is a terminal device.

29. A communication apparatus, comprising:

means for determining, at a first device, first information regarding whether a frequency domain component associated with a subband is selected for at least one data stream in response to receiving a first plurality of reference signals from a second device over a physical resource block in the subband;

means for determining at least one codebook for the first information based on a first configuration, the first configuration indicating a mapping between one or more candidate content of the first information and one or more corresponding codebooks; and

Means for transmitting a subset of a second plurality of reference signals having the at least one codebook to the second device on a portion of the physical resource blocks, the portion of the physical resource blocks determined according to a second configuration, the second configuration indicating whether the at least one codebook is to be carried for the physical resource blocks.

30. A communication apparatus, comprising:

means for receiving, at the first device, a second plurality of reference signals from the first device on physical resource blocks in the subband;

means for determining first information regarding whether frequency domain components associated with the subbands are selected for at least one data stream based on a first configuration and a second configuration, the first configuration indicating a mapping between one or more candidate content of the first information and one or more corresponding codebooks, and the second configuration indicating whether the at least one codebook is to be carried for the physical resource block; and

means for transmitting channel state information to the first device based on the first information.

31. A non-transitory computer readable medium comprising program instructions for causing an apparatus to perform the method of any one of claims 12 to 21.

32. A non-transitory computer readable medium comprising program instructions for causing an apparatus to perform the method of any one of claims 22 to 28.