CN116648969A

CN116648969A - Communication method and device

Info

Publication number: CN116648969A
Application number: CN202080106592.9A
Authority: CN
Inventors: 余健; 余雅威; 郭志恒
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2020-11-19
Filing date: 2020-11-19
Publication date: 2023-08-25
Also published as: WO2022104665A1

Abstract

The application provides a communication method and a communication device. The communication method comprises the following steps: the network device sends downlink control information to the terminal device, the downlink control information comprises indexes of N precoding matrix subsets, the terminal device determines at least N precoding matrices from the N precoding matrix subsets according to the downlink control information, and sends uplink signals based on the at least N precoding matrices, so that the signaling overhead of sub-band precoding indication information and the complexity of the terminal device for detecting the sub-band precoding indication information are reduced while the transmission performance is improved.

Description

Communication method and device

Technical Field

The present application relates to the field of wireless communications, and in particular, to a communication method and apparatus.

Background

In uplink transmission, when the terminal and the base station are both configured with multiple antennas, the base station needs to transmit precoding information to the terminal through downlink control information (downlink control information, DCI), the terminal obtains a precoding matrix according to the precoding information, maps data to be transmitted to multiple antenna ports through the precoding matrix, and transmits a physical uplink shared channel (physical uplink shared channel, PUSCH). Precoding makes the transmitted signal more directional rather than simply radiating all around.

The physical uplink shared channel supports a codebook-based transmission mode and a non-codebook-based transmission mode. For codebook-based transmission mode, the base station selects a precoding matrix in the codebook and sends a transmit precoding indication (Transmitted Precoding Matrix Indicator, TPMI) to the terminal, where the TPMI corresponds to one precoding matrix. The accuracy of the precoding matrix may affect the demodulation performance of PUSCH. The NR system only supports uplink broadband precoding, namely, the same precoding matrix is adopted on the scheduled bandwidth, when the frequency selection characteristic of a channel is relatively large, the mode can cause the performance loss of the system, if the subband precoding is adopted, the base station sends information to the terminal equipment to indicate the TPMI of each subband, the signaling overhead can be increased, and therefore, when the uplink precoding is designed, the aspects of reducing the signaling overhead and improving the transmission performance are mutually contradictory.

Disclosure of Invention

The application provides a communication method and a communication device, which are used for reducing signaling overhead of subband precoding.

In a first aspect, the present application provides a communication method, where the execution body of the method may be a terminal device, or may be a chip applied in the terminal device. The following describes an example in which the execution subject is a terminal device. The method comprises the steps that a terminal device receives downlink control information sent by a network device, wherein the downlink control information comprises indexes of N precoding matrix subsets, the N precoding matrix subsets are one or more of a plurality of precoding matrix subsets divided by a first codebook, and at least one precoding matrix subset comprises at least two precoding matrices in the N precoding matrix subsets. The terminal equipment determines at least N precoding matrixes in the N precoding matrix subsets, and transmits uplink signals based on the determined at least N precoding matrixes, wherein N is a positive integer.

In the above embodiment, the terminal device may select one or more precoding matrices from the N precoding matrix subsets for transmitting the uplink signal, thereby improving transmission performance. Moreover, the terminal device receives the indication information of the indexes of the precoding matrix subsets through the downlink control information, and because the number of the precoding matrix subsets divided by the first codebook can be smaller or far smaller than the number of the precoding matrices contained in the first codebook, compared with the case of receiving the indication information of the indexes of the precoding matrices contained in the whole first codebook, the cost of the downlink control information can be reduced by receiving the indication information of the indexes of the precoding matrix subsets, thereby being beneficial to reducing the complexity of detection of the terminal device and the power consumption of the terminal device.

In an optional embodiment, the downlink control information further includes resource indication information for indicating the first downlink reference signal, and the terminal device determines at least N precoding matrices among the N precoding matrix subsets based on the first downlink reference signal on the resource indicated by the resource indication information.

In the above embodiment, the terminal device determines at least N precoding matrices based on the first downlink reference signal, and because the first downlink reference signal may reflect the channel state of the downlink channel, the terminal device may determine an appropriate precoding matrix in consideration of the influence of the channel state, so as to obtain better multi-antenna gain.

In an optional implementation manner, the uplink signal is a physical uplink shared channel PUSCH, the PUSCH occupies M subbands, the downlink control information further includes indication information of the M subbands, at least N precoding matrices are M precoding matrices, each subband in the M subbands corresponds to one of the M precoding matrices, and M is a positive integer greater than N. At this time, there are precoding matrices corresponding to at least two subbands in the M subbands that belong to the same subset of precoding matrices. The terminal device transmits PUSCH on M subbands based on the M precoding matrices.

In an optional implementation manner, the uplink signal is a physical uplink shared channel PUSCH, the PUSCH occupies N subbands, that is, M is equal to N, the downlink control information further includes indication information of the N subbands, the N precoding matrix subsets are in one-to-one correspondence with the N subbands, and the terminal device sends the PUSCH on the N subbands based on the N precoding matrices.

In an optional implementation manner, the uplink signal is a physical uplink shared channel PUSCH, the PUSCH occupies M subbands, M is greater than N, the downlink control information further includes indication information of the M subbands, the N precoding matrix subsets are a precoding matrix subset, and N is 1. And respectively determining the precoding matrix of each sub-band in the M sub-bands according to one precoding matrix subset, wherein at least N precoding matrices are M precoding matrices, the M sub-bands correspond to the M precoding matrices one by one, and the terminal equipment sends PUSCH (physical uplink shared channel) on the M sub-bands based on the M precoding matrices.

In the above manner, the index of the downlink control information indicating the subset of precoding matrices and the subband indicating information, and each subband corresponds to one precoding matrix, for example, the precoding matrix which is most suitable for the terminal device to send the uplink signal, which is beneficial to improving the transmission performance.

It should be noted that the M precoding matrices may be completely different M precoding matrices or partially identical precoding matrices, which is not limited by the embodiment of the present invention.

In an alternative embodiment, at least two different precoding matrix subsets of the plurality of precoding matrix subsets correspond to different values of a first codebook parameter, the first codebook parameter comprising a phase. In an optional manner, the number of the precoding matrix subsets is K, the first codebook includes L precoding matrices, and the index of the precoding matrix included in each of the K precoding matrix subsets satisfies the followingThe values of (2) are the same; alternatively, the index of the precoding matrix included in each precoding matrix subset satisfies the same value of mod (j, K). Wherein j is the index of the precoding matrix in the first codebook,in order to lower the round-down function,is a top-rounding function.

In an alternative way, the first codebook is generated based on a discrete fourier transform matrix, at least two different ones of the plurality of precoding matrix subsets corresponding to different column vectors in the discrete fourier transform matrix.

In an alternative manner, the downlink control information further includes an index of at least one precoding matrix, where the at least one precoding matrix is a precoding matrix not intended for the terminal device or a precoding matrix not intended for the terminal device. In an alternative manner, the precoding matrix used by the undesired terminal equipment is a precoding matrix of an interference channel.

In the above manner, when the terminal device determines at least N precoding matrices from the N precoding matrix subsets, the terminal device considers the precoding matrices that the network device does not expect the terminal device to use, so that the terminal device can reduce interference as much as possible and improve transmission performance

In a second aspect, the present application provides a communication method, where the execution body of the method may be a network device, or may be a chip applied in the network device. The following describes an example in which the execution subject is a network device. The network equipment determines N precoding matrix subsets, the network equipment sends downlink control information to the terminal equipment, the downlink control information comprises indexes of the N precoding matrix subsets, the N precoding matrix subsets are one or more of a plurality of precoding matrix subsets divided by a first codebook, and at least one precoding matrix subset comprises at least two precoding matrices.

In the above manner, the network device indicates the index of one or more precoding matrix subsets through the downlink control information, and since the number of precoding matrix subsets divided by the first codebook may be smaller or far smaller than the number of precoding matrices included in the first codebook, the network device may reduce signaling overhead of the downlink control information compared with the case where the index of the precoding matrix included in the first codebook is indicated through the downlink control information.

In an alternative embodiment, at least N precoding matrices correspond to M subbands, where M is greater than or equal to N, and the network device receives uplink signals on the M subbands.

In an alternative embodiment, at least N precoding matrices are M, where the M precoding matrices are in one-to-one correspondence with M subbands, and the network device receives the uplink signal on the M subbands.

In an alternative embodiment, the uplink signal is a physical uplink shared channel PUSCH.

In an alternative embodiment, the N precoding matrix subsets are one precoding matrix subset, N is 1, and at least n+1 precoding matrices belong to the same precoding matrix subset.

In an alternative embodiment, at least two different precoding matrix subsets of the plurality of precoding matrix subsets correspond to different values of a first codebook parameter, the first codebook parameter comprising a phase.

In an alternative embodiment, the number of the precoding matrix subsets is K, the first codebook includes L precoding matrices, and the index of the precoding matrix included in each of the K precoding matrix subsets satisfies:the values of (2) are the same; alternatively, the index of the precoding matrix included in each precoding matrix subset satisfies the same value of mod (j, K). Wherein j is the firstAn index to each precoding matrix in a codebook,in order to lower the round-down function,is a top-rounding function.

In an alternative manner, the downlink control information further includes an index of at least one precoding matrix, where the at least one precoding matrix is a precoding matrix not intended for the terminal device or a precoding matrix not intended for the terminal device.

In an alternative way, the precoding matrix used by the undesired terminal equipment is a precoding matrix of the interfering channel.

According to the mode, the network equipment indicates the indexes of the N precoding matrix subsets and simultaneously indicates the precoding matrix which is not expected to be used by the terminal equipment, so that the terminal equipment is facilitated to reduce interference as much as possible, and the transmission performance is improved.

In a third aspect, a communication device is provided, the communication device having functionality to implement the actions in the method instances of the first aspect described above. The functions may be implemented by hardware, or may be implemented by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the functions described above. In one possible design, the communication device includes: the receiving unit is configured to receive downlink control information, where the downlink control information includes indexes of N precoding matrix subsets, the N precoding matrix subsets are one or more of a plurality of precoding matrix subsets divided by the first codebook, and at least one precoding matrix subset includes at least two precoding matrices among the N precoding matrix subsets. A processing unit for determining at least N precoding matrices among the N precoding matrix subsets. And the transmitting unit is used for transmitting the uplink signals based on at least N precoding matrixes, wherein N is a positive integer.

These modules may perform the corresponding functions in the method examples of the first aspect, which are specifically referred to in the detailed description of the method examples and are not described herein. Meanwhile, regarding the technical effects brought about by the third aspect or the corresponding embodiments, reference may be made to the description of the technical effects of the first aspect or the corresponding embodiments.

In a fourth aspect, a communication device is provided having functionality to implement the actions in the method instances of the second aspect described above. The functions may be implemented by hardware, or may be implemented by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the functions described above. In one possible design, the communication device includes: and the processing unit is used for determining N precoding matrix subsets. A transmitting unit, configured to transmit downlink control information, where the downlink control information includes indexes of N precoding matrix subsets, the N precoding matrix subsets are one or more of a plurality of precoding matrix subsets divided by the first codebook, and at least one precoding matrix subset includes at least two precoding matrices among the N precoding matrix subsets.

These modules may perform the corresponding functions in the method examples of the second aspect described above, and are specifically described in detail in the method examples, which are not repeated here. Meanwhile, regarding the technical effects brought about by the third aspect or the corresponding embodiments, reference may be made to the description of the technical effects of the first aspect or the corresponding embodiments.

In a fifth aspect, a communication apparatus is provided, which may be a terminal device in the above method embodiment, or a chip provided in the terminal device, or a larger device including the terminal device. The communication device includes at least one processor and interface circuitry, and optionally, memory. Wherein the interface circuit is adapted to provide instructions and/or data input or output to the at least one processor, the memory is adapted to store a computer program or instructions, at least the processor is coupled to the memory, the interface circuit, and when the at least one processor executes the computer program or instructions, the communication device is adapted to perform the method performed by the terminal device in the above-described method embodiments.

In a sixth aspect, a communication apparatus is provided, where the communication apparatus may be a network device in the above method embodiment, or a chip provided in the network device, or a larger device including the network device. The communication device includes at least one processor and interface circuitry, and optionally, memory. Wherein the interface circuit is adapted to provide instructions and/or data input or output to the at least one processor, the memory is adapted to store a computer program or instructions, at least the processor is coupled to the memory, the interface circuit, and when the at least one processor executes the computer program or instructions, the communication device is adapted to perform the method performed by the network apparatus in the above method embodiments.

In a seventh aspect, there is provided a computer program product comprising: computer program code which, when executed, causes the method performed by the terminal device in the above aspects to be performed.

In an eighth aspect, there is provided a computer program product comprising: computer program code which, when executed, causes the method performed by the network device in the above aspects to be performed.

In a ninth aspect, the present application provides a chip system, where the chip system includes a processor, and the processor is configured to implement a function of a terminal device in the method of the above aspects. In one possible design, the chip system further includes a memory for holding program instructions and/or data. The chip system can be composed of chips, and can also comprise chips and other discrete devices.

In a tenth aspect, the present application provides a chip system, where the chip system includes a processor, and the processor is configured to implement the functions of the network device in the methods of the above aspects. In one possible design, the chip system further includes a memory for holding program instructions and/or data. The chip system can be composed of chips, and can also comprise chips and other discrete devices.

In an eleventh aspect, the present application provides a computer-readable storage medium storing a computer program which, when executed, implements the method performed by the terminal device in the above aspects.

In a twelfth aspect, the present application provides a computer readable storage medium storing a computer program which, when executed, implements the method performed by the network device in the above aspects.

In a thirteenth aspect, a communication system is provided, the communication system comprising a network device and a terminal device according to any of the above aspects.

Drawings

FIG. 1 is a schematic diagram of a possible communication architecture according to the present application;

FIG. 2 is a flow chart of a communication method according to the present application;

fig. 3 is a schematic hardware structure diagram of a network device and a terminal device provided by the present application;

FIG. 4 is a schematic view of one possible apparatus provided by the present application;

FIG. 5 is a schematic view of one possible apparatus provided by the present application;

fig. 6 is a schematic structural diagram of a possible communication device according to the present application;

Detailed Description

the technical scheme of the embodiment of the application can be applied to various communication systems. Such as long term evolution (long term evolution, LTE) systems, fifth generation (5th generation,5G) mobile communication systems, and future mobile communication systems.

As shown in fig. 1, a schematic diagram of a possible network architecture, including a terminal device 110 and an access network device 120, and optionally a core network device 130, is suitable for an embodiment of the present application. Communication between terminal device 110 and access network device 120 may be via a Uu air interface, which may be understood as an interface (universal UE to network interface) between general purpose terminal device 110 and access network device 120. The Uu air interface transmission includes uplink transmission and downlink transmission.

For example, uplink transmission refers to terminal device 110 sending an uplink signal to access network device 120. The uplink Signal may include one or more of uplink data, uplink control information, or Reference Signal (RS). The channel used for transmitting the uplink signal is called an uplink channel, which may be a PUSCH or a physical uplink control channel (physical uplink control channel, PUCCH). PUSCH is used to carry uplink data, which may also be referred to as uplink data information. PUSCH may also be used to carry uplink control information. The PUCCH is used to carry uplink control information (uplink control information, UCI) fed back by the terminal device. The UCI may include one or more of channel state information (channel state information, CSI), acknowledgement (ACK), negative acknowledgement (negative acknowledgement, NACK), or scheduling request (scheduling request, SR), etc.

Taking a Fifth generation (5G) communication system as an example, the core network device 130 includes: access and mobility management functions (access and mobility management function, AMF), session management functions (session management function, SMF), user plane functions (user plane function, UPF), etc., the access network device 120 is a device having a wireless transceiving function for communicating with the terminal device 110. The access network device includes, but is not limited to, a base station (BTS, node B, eNodeB/eNB, or gNodeB/gNB), a transceiver point (transmission reception point, TRP), a base station for subsequent evolution of 3GPP, an access Node in a WiFi system, a wireless relay Node, a wireless backhaul Node, and the like. The base station may be: macro base station, micro base station, pico base station, small station, relay station, etc. Multiple base stations may support networks of the same access technology as mentioned above, or may support networks of different access technologies as mentioned above. A base station may comprise one or more co-sited or non-co-sited transmission reception points. In the following embodiments, the above-mentioned access network device and core network device are collectively referred to as a network device with respect to a terminal device.

The following description is given of some terms or terminology used in connection with the present application, which also forms part of the summary of the application.

1. Terminal equipment

A terminal device may be simply referred to as a terminal, also referred to as a User Equipment (UE), and is a device having a wireless transceiving function. The terminal device may be deployed on land, including indoors or outdoors, hand-held or vehicle-mounted; can also be deployed on the water surface (such as ships, etc.); but may also be deployed in the air (e.g., on an aircraft, drone, balloon, satellite, etc.). The terminal device can be a mobile phone, a car, a tablet personal computer, a smart sound box, a detector, a gas station sensor, a computer with a wireless receiving and transmitting function, a virtual reality terminal device, an augmented reality terminal device, a wireless terminal device in industrial control, a wireless terminal device in unmanned driving, a wireless terminal device in telemedicine, a wireless terminal device in a smart grid, a wireless terminal device in transportation safety, a wireless terminal device in a smart city, a wireless terminal device in a smart home or the like. The terminal device may also be fixed or mobile. The embodiment of the present application is not limited thereto.

In the embodiment of the present application, the device for implementing the function of the terminal may be a terminal device; or a device, such as a chip system, capable of supporting the terminal device to realize the function, which may be installed in the terminal device. In the embodiment of the application, the chip system can be composed of chips, and can also comprise chips and other discrete devices. In the technical solution provided in the embodiment of the present application, the device for implementing the function of the terminal device is an example of the terminal device, and the technical solution provided in the embodiment of the present application is described.

2. Network equipment

The network device may be an access network device, which may also be referred to as a radio access network (radio access network, RAN) device or a base station, which is a device that provides wireless communication functionality for the terminal device. Access network devices include, for example, but are not limited to: next generation node B (gNB) in 5G, evolved node B (eNB), baseband unit (BBU), transmit-receive point (transmitting and receiving point, TRP), transmit point (transmitting point, TP), access network equipment in future mobile communication systems, access points in WiFi systems, or the like. The access network device may also be a radio controller, a Centralized Unit (CU), and/or a Distributed Unit (DU) in the cloud radio access network (cloud radio access network, CRAN) scenario, or the network device may be a relay station, an in-vehicle device, a network device in a PLMN network of future evolution, etc.

The terminal device may communicate with multiple access network devices of different technologies, for example, the terminal device may communicate with an access network device supporting long term evolution (long term evolution, LTE), may communicate with an access network device supporting 5G, and may also communicate with an access network device supporting LTE and an access network device supporting 5G simultaneously. The embodiments of the present application are not limited.

In the embodiment of the present application, the device for implementing the function of the network device may be a network device; or may be a device, such as a system-on-a-chip, capable of supporting the network device to perform this function, which may be installed in the network device. In the technical solution provided in the embodiment of the present application, the device for implementing the function of the network device is exemplified by the network device, and the technical solution provided in the embodiment of the present application is described.

3. Uplink (UL) communication and Downlink (DL) communication

In a wireless communication system, communications can be classified into different types according to the kinds of transmitting nodes and receiving nodes. The transmission of information from a network device to a terminal device is generally referred to as Downlink (DL) communication, and the transmission of information from a terminal device to a network device is generally referred to as Uplink (UL) communication. In fourth generation (Fourth generation, 4G) and 5G wireless communication systems, new radio access technology (new radio access technology, NR) systems, uplink communications may obtain channel state information (Channel state information, CSI) measurements via sounding reference signals (Sounding reference signal, SRS) and downlink communications may obtain channel state information via channel state information reference signals (CSI-RS).

4. Time-frequency resource granularity

The time-frequency resources may also be referred to as resources for short, and the granularity of the time-frequency resources may also be referred to as resource granularity for short. In an NR system, two types of resource granularity of uplink scheduling support, or two types of time-frequency resource allocation exist in NR, namely, an allocation type (also called resource allocation 0, resource allocation 0) based on a resource group (resource block group, RBG) and an allocation type (also called resource allocation, resource allocation 1) based on a Resource Block (RB). Each RB includes 12 Resource Elements (REs) in the frequency domain, that is, 12 subcarriers. Each RBG contains one or more RBs, and the number of RBs each RBG contains is also referred to as the size of the RBG. In the present application, the size of each RBG may be related to a Bandwidth Part (BWP). For example, when the number of RBs included in the bandwidth part BWP is different, the number of RBs included in each RBG is also different. Alternatively, the size of each RBG may be uncorrelated with BWP, and the size of each RBG may be indicated by higher layer signaling.

5. Sub-band

One sub-band includes one or more RBs in the frequency domain, or one sub-band may include one or more RBGs in the frequency domain. Since each RBG also includes a plurality of RBs, the size of the subbands may be the same as or different from the RBG. For example, assuming that 10 RBs are included in one bandwidth part BWP, two consecutive RBs are divided into subbands, then 5 subbands may be divided. Alternatively, the division of the sub-bands may be divided based on a scheduling bandwidth that is less than or equal to the bandwidth portion BWP size. The scheduling bandwidth is the bandwidth corresponding to the actual frequency domain resource occupied by the PUSCH transmitted by the terminal device at a certain time (such as a certain slot). One sub-band in the embodiment of the present application may be one RBG occupied by PUSCH or may be one RB occupied by PUSCH.

6. Frequency selective gain and beamforming gain

The frequency selection gain refers to that the network device calculates the priority of each sub-band according to the channel quality indication (Channel Quality Indicator, CQI) or the signal-to-interference-and-noise ratio of each sub-band, and performs scheduling on each sub-band according to the priority of sub-band scheduling of each terminal device, so that each terminal device performs signal transmission on the sub-band with the best channel quality.

For the beamforming gain, the terminal device weights the uplink signal to form a narrow beam aimed at the network device, or understand as a directional beam, so as to aim the energy at the target network device, which is beneficial to improving the strength of the received signal.

7. Channel reciprocity

In general, when the terminal device may directly derive the uplink channel information through the downlink channel information, or when the network device may directly derive the downlink channel information through the uplink channel information, it may be considered that the communication system has a channel reciprocity feature.

8. Codebook

A codebook is made up of a plurality of precoding matrices. Taking the terminal device transmitting antenna port as the 2 antenna port as an example, table 1 and table 2 give examples of codebooks when the terminal device transmits one stream and two streams, where each precoding matrix in the codebook corresponds to an index value, or referred to as TPMI index.

TABLE 1

Table 1 is an example of a codebook when a terminal device transmits an antenna port of 2 and a rank of 1, and in table 1, there are six precoding matrices in total, and the corresponding TPMI index values are respectively 0 to 5.

TABLE 2

Table 2 is a codebook when the terminal transmitting antenna port is 2 and the rank is 2, and there are three precoding matrices, and the corresponding TPMI index values are respectively 0 to 2.

In tables 1 and 2, W is a precoding matrix or vector. After the precoding matrix is determined, the terminal device maps PUSCH data to each antenna port through the precoding matrix. For example, the terminal device may map data of PUSCH to an antenna port through the procedure of formula (1-1):

y ^(υ-1) (i) For the data prior to precoding, v is the layer index,for the precoded data, i.e. corresponding antenna port p _ρ-1 Data on the same. For single-layer transmission of two antennas, i.e. p _ρ-1 2 and v is 1. If single antenna transmission is performed, W defaults to 1, which is equivalent to not precoding.

The network device may obtain channel state information of the uplink channel by measuring the SRS, and select the precoding matrix. For example, the precoding matrix most suitable for the current uplink channel may be used, and TPMI of the precoding matrix may be sent to the terminal device. In one example of selecting the precoding matrix, the network device may select an optimal precoding matrix for uplink PUSCH transmission based on capacity maximization criteria. After the network device determines the TPMI, the TPMI needs to be sent to the terminal device before the terminal device sends the uplink data, so as to inform the terminal device of what precoding matrix is used to send the uplink data. For example, taking a codebook of a transmission layer as an example, assume that the terminal device is k, and in a channel from the terminal device to the network device, power on the mth frequency domain resource is p _k,m Signal to interference plus noise ratio (Signal to Interference) on the mth frequency domain resourceplus Noise Ratio, SINR) is gamma _k,m . The channel on the mth frequency domain resource of the terminal equipment k is H _k,m A matrix. SINR is defined as:

wherein g _k,m For network devices to receive weight coefficients on antennas, w _k Is the precoding matrix of terminal equipment k. For example, g can be obtained by solving by adopting a matched filtering method _k,m ＝(H _k,m w _k ) ^H ，I _k,m Is the interference covariance matrix between cells, sigma ² Is the noise power. An alternative selection criterion is to select the precoding matrix by a capacity maximization criterion:

where Φ is the precoding matrix set. When the same precoding matrix is adopted on each frequency domain resource of the terminal equipment, w _k Independent of the frequency domain resource index.

In the embodiment of the invention, in the transmission mode based on the codebook, the network equipment and the terminal equipment can use the same codebook. The precoding matrices in different codebooks may also be different. The embodiment of the invention can use some existing candidate codebooks, and can also use some new codebooks. For example, a codebook generated based on structured antenna grouping or a codebook generated based on discrete fourier (Discrete Fourier Transform, DFT).

In one embodiment, a codebook generated based on structured antenna grouping is employed. This embodiment may divide the codebook into precoding matrix subsets based on phase. Further, in the codebook generated based on the structured antenna grouping, each precoding matrix corresponds to one phase value or a plurality of phase valuesThe phase values, therefore, divide the precoding matrix included in the codebook into subsets based on the phase corresponding to the precoding matrix, and constitute a plurality of precoding matrix subsets. For example, for a codebook of 8 antenna ports, if A ₁ For a precoding matrix with 8 antenna ports and rank 1, the codebook is generated as follows:

where θ, ε, δ, φ are different phases, which can also be understood as phase variables since each phase can have multiple values. B, D, E, F.epsilon.exp (j.theta.), p is A ₁ The number of rows, q, is the number of columns, N ₁ ,N ₁ ,N ₃ ,N ₄ The quantization factor can control the precision of the codebook, and the larger the quantization factor is, the more phases are selected, and the higher the precision of the precoding matrix in the codebook is. The quantization factor may be configured by radio resource control (Radio Resource Control, RRC) signaling or by the medium access control unit (Media Access Control Control Element, MAC CE). For the case of non-8 antenna ports, e.g. 2 antenna or 4 antenna ports, the method is still applicable, except that the magnitude of the phase may be different.

For the codebook generated based on DFT, taking the case of 8 antenna ports as an example, the structure of the precoding matrix of this method can be expressed as:

wherein v is _t,m The precoding matrix formed in the same polarization direction is composed of a DFT matrix, and θ is the phase shift in different polarization directions. The method is also applicable to codebook generation in the case of non-8 antenna port numbers, such as the case of antenna port numbers of 2,4, or 16.

Since the precoding matrix in the codebook is divided into a plurality of precoding matrix subsets, in this case, the codebook may also be understood as a codebook set.

The selection of the precoding matrix may affect the demodulation performance of the PUSCH, and an unsuitable precoding matrix may cause the PUSCH demodulation performance to be degraded. Therefore, the larger the codebook, the larger the number of precoding matrices in the codebook, and the more precoding matrices are available for selection, and thus the higher the accuracy of the precoding matrices, but the greater the signaling overhead of the indication information indicating TPMI at this time.

For example, if 256 precoding matrices are included in the codebook, 8 bits are required to indicate the precoding matrix index. Based on this, if there are M subbands, each of which can select a precoding matrix in the codebook, as indicated by the subbands, 8*M bits are required to indicate one precoding matrix index corresponding to each subband, and 320 bits are required, assuming that m=40. If the 320 bits are directly carried by DCI, on one hand, the DCI occupies more control channel resources, which may cause congestion of the control channel and decrease reliability, and on the other hand, the number of bits carried by the DCI exceeds the size of the DCI used for downlink scheduling, which may increase the number of blind detection of the terminal device.

Currently, only bandwidth-based precoding matrices are considered when designing the precoding matrix, i.e. the same precoding matrix is used on all scheduling resources allocated by the terminal device. This approach is applicable to situations where the frequency domain channel is relatively flat and the channel variation is small. When the fluctuation of the channel in the frequency domain is large, the bandwidth-based precoding matrix may not match the variation of the channel, which is disadvantageous to obtain the frequency-selective gain and the beamforming gain. In addition, when the multi-terminal equipment is paired, as different terminal equipment can be paired on different frequency domain resource blocks, if a precoding matrix based on bandwidth is adopted, interference among paired terminal equipment is not easy to suppress.

In one embodiment of the present application, a communication method is provided for enabling an uplink sub-band level precoding matrix while reducing signaling overhead. Referring to fig. 2, a flow chart of the method is shown. In the following description, the application of the method to the network architecture shown in fig. 1 is taken as an example.

For ease of description, hereinafter, this method is exemplified by the network device and the terminal device. Because the embodiment of the present application is exemplified by the network architecture shown in fig. 1. Thus, the network device described below is, for example, an access network device in the network architecture shown in fig. 1, and the terminal device described below may be a terminal device in the network architecture shown in fig. 1.

Referring to fig. 2, a flow chart of a communication method provided by the present application is shown. The method mainly comprises S21 to S25.

S21: and the terminal equipment sends the SRS to the network equipment, and the network equipment receives the SRS sent by the terminal equipment correspondingly.

Specifically, the terminal device sends an SRS to the network device on an SRS resource configured by the network device, and correspondingly, the network device receives the SRS on the SRS resource configured by the network device, measures an uplink channel, and obtains channel state information.

S22: the network device determines N precoding matrix subsets.

Specifically, the network device determines N precoding matrix subsets according to the state information of the uplink channel and the scheduling bandwidth obtained by SRS measurement. The N precoding matrix subsets are one or more of a plurality of precoding matrix subsets divided by the first codebook, and at least one precoding matrix subset comprises at least two precoding matrices. For the N precoding matrix subsets determined by the network device, the N precoding matrix subsets may be N different precoding matrix subsets, or may include two or more identical precoding matrix subsets, for example, the network device determines 5 precoding matrix subsets, where there are two precoding matrix subsets that are the same precoding matrix subset. This is because the scheduling bandwidth may include a plurality of sub-bands, and when the network device determines N sub-sets of precoding matrices, the network device determines a sub-set of precoding matrices based on each sub-band in consideration of channel state information on each sub-band, and at this time, there may be two or more sub-bands in the scheduling bandwidth that are suitable for the same sub-set of precoding matrices.

The first codebook may be one of existing candidate codebooks, may be a codebook generated based on a structured antenna packet, may be a codebook generated based on DFT transformation, or may be a codebook generated in other manners. Since the first codebook includes a plurality of precoding matrices, the first codebook may be divided into a plurality of precoding matrix subsets, each of which includes a plurality of precoding matrices, and of course, there may be one or more precoding matrix subsets including only one precoding matrix. When N is greater than 1, the plurality of precoding matrices in the first codebook are divided into different subsets of precoding matrices. The N precoding matrix subsets may include one or more precoding matrix subsets among the plurality of precoding matrix subsets divided by the first codebook, or may include all precoding matrix subsets among the plurality of precoding matrix subsets divided by the first codebook, and in this case, the N precoding matrix subsets may be understood as the first codebook itself. Since each precoding subset also comprises one or more precoding matrices, the first codebook may be understood as a set of codebooks if each precoding matrix subset is considered as a codebook.

In an alternative manner, the first codebook includes at least one first codebook parameter, and at least two different precoding matrix subsets among the plurality of precoding matrix subsets divided by the first codebook correspond to different values of the first codebook parameter, where the codebook parameter includes a phase. Optionally, the plurality of precoding matrices in the first codebook are divided into a plurality of precoding matrix subsets by phase. The phase may be a phase offset between antennas or antenna ports. Since each phase can correspond to a different value, the phase can also be understood as a phase variable. For example, when the first codebook is generated based on structured antenna groupingThere may be multiple phase variations due to the codebook generated based on the structured antenna packet. A subset of precoding matrices may be constructed by fixing the values of one or more phases and traversing the values of the remaining one or more phases. The value of each phase is determined based on a quantization factor, i.e. the number of most selectable values per phase. The quantization factor may be a predefined value, or may be indicated by indication information, where the indication information indicating the quantization factor may be carried in RRC signaling, or may be carried in MAC CE, or may be carried in RRC signaling and MAC CE. Based on the division manner, the precoding matrix in the first codebook can be divided into a plurality of precoding matrix subsets, and after the division of the precoding matrix subsets is determined, each subset needs to be numbered in order to indicate different subsets, and the number of the subset can be understood as the index of each precoding matrix subset. Different precoding matrix subsets may be indicated by different status values of one or more bits of an indication field, each status value characterizing one precoding matrix subset. For example, if the codebook generated based on the structured antenna grouping has 4 phases, θ, ε, δ, φ, fixed θ, ε, δ values, by traversing the possible values of φ To construct a subset of precoding matrices, wherein each possible value of phi corresponds to a precoding matrix. Further, the quantization factors of the phases theta, epsilon, delta and phi are N respectively ₁ ,N ₁ ,N ₃ ,N ₄ That is, θ, ε, δ, φ each have N ₁ ,N ₁ ,N ₃ ,N ₄ Table 3 shows one way of dividing the first codebook into a plurality of precoding matrix subsets.

TABLE 3 Table 3

In Table 3, there are four phase variables θ, ε, δ, φ, which are the first phase to the fourth phase, respectively, each phase variable corresponds to a quantization factor N ₁ ,N ₁ ,N ₃ ,N ₄ The values of (a) are 4, and the values correspond to 64 precoding matrix subsets. For each subset, the three phases are fixed values, and the different values of the remaining one phase correspond to the precoding matrices in the subset. For example, subset number 1, the first phase, the second phase, and the third phase are all fixed values, N of the fourth phase ₄ Each value, i.e. N in the precoding matrix subset corresponding to number 1 ₄ And precoding matrices. Alternatively, for 64 precoding matrix subsets, different precoding matrix subsets may be indicated by different status values of one 6-bit indication field of the indication information.

In generating the codebook, in order to reduce the overhead, there may be a case where two phases are equal, for example, in the case of the above 4 phase variables, if two phase variables are equal, this corresponds to only 3 phases, or it is understood that only 3 phases are variable at this time, that is, only the phase values of 3 phases are needed to determine a subset of the precoding matrix. For example, there are 4 phases θ, ε, δ, φ, which are respectively the first phase to the fourth phase, and take the second phase and the third phase as the same example, that is, ε and δ are the same, at this time, only the values of two phases need to be fixed, and the values of the remaining one phase need to be traversed to construct a precoding matrix subset. Table 4 shows an example of the first codebook divided into a plurality of precoding matrix subsets when there are 4 phases and there are two phases equal.

TABLE 4 Table 4

In Table 4, N ₁ ,N ₁ ,N ₃ ,N ₄ Is of the value of (2)All are 4, and there are three variable phases θ, ε, δ, which are the first phase, the second phase, and the fourth phase, respectively, where the first phase and the third phase are the same, and the second phase and the third phase are the same. For 3 variable phases, only the values of 2 phase variables are fixed, and the precoding matrix in one precoding matrix subset can be determined by traversing the values of the remaining 1 phase. For example, the subset number 1, the first phase and the second phase are fixed, 4 different values of the fourth phase correspond to 4 precoding matrices in the precoding matrix subsets, 3 phases, and the quantization factor of each phase is 4, and the total number of the precoding matrix subsets is 16, and at this time, different precoding matrix subsets can be indicated by different state values of the 4-bit indication field.

For example, there is only one phase variable, and the subset of precoding matrices corresponding to the one phase may be represented as the following table 5:

TABLE 5

In table 5, θ is the above phase, and a subset of precoding matrices can be constructed by traversing different values of θ.

For example, two phases are variable, the value of one phase is fixed, and the value of the other phase is traversed to construct a subset of precoding matrices. One possible example is shown with reference to table 6:

TABLE 6

In Table 6, θ and ε are the first phase and the second phase, respectively, and θ is the fixed value of θ _x And traversing different values of the second phase epsilon to construct a precoding matrix subset.

The above description of the phase and the quantization factor is merely exemplary, and the value of the phase and the size of the quantization factor may be in other forms, which are not limited by the present application. Meanwhile, in the above example, a precoding matrix subset is constructed by traversing the values of one phase and fixing the values of the remaining phases, and in practical application, a precoding matrix subset may be constructed by traversing two or more phases and fixing the values of the remaining phases.

In yet another alternative, the first codebook includes L precoding matrices, each of the L precoding matrices corresponds to an index value of one precoding matrix, the L precoding matrices are divided into K precoding matrix subsets, each precoding matrix subset includes one or more precoding matrices, and for each precoding matrix subset, the index value of the precoding matrix included in each precoding matrix subset satisfies Or the index values of the precoding matrixes contained in the same value satisfy mod (j, K), wherein j is the index of the precoding matrix,in order to lower the round-down function,is a top-rounding function. For convenience of description, the following equation is satisfied by an index representing the precoding matrix in each precoding matrix subsetThe index of the precoding matrix in each precoding matrix subset is represented by a relation two, and the values of mod (j, K) are the same.

For example one, when L is equal to 28 and k is equal to 4, the first codebook contains 28 precoding matrices, and index values of the precoding matrices corresponding to the 28 precoding matrices are respectively 0 to 27 and divided into 4 precoding matrix subsets. When the index values of the precoding matrices in each precoding matrix subset satisfy the relation one, optionally, the precoding matrices from index value 0 to index value 6, from index value 7 to index value 13, and from index value 14 to index value 20, and from index value 21 to index value 27 respectively belong to the first to fourth precoding matrix subsets: substituting index values of the precoding matrixes contained in the first subset of precoding matrixes into a relation one to obtain values of 0; substituting index values of the precoding matrixes contained in the second subset of precoding matrixes into a relation one to obtain values 1; substituting index values of the precoding matrixes contained in the third subset of precoding matrixes into a relation one to obtain values of 2; and substituting index values of precoding matrixes contained in the fourth subset of precoding matrixes into the relation one to obtain values of 3.

For example two, when L is equal to 28 and k is equal to 4, the first codebook contains 28 precoding matrices, and index values of the precoding matrices corresponding to the 28 precoding matrices are respectively 0 to 27 and divided into 4 precoding matrix subsets. When the index values of the precoding matrices in each precoding matrix subset satisfy the same value of the substituted relation two, it can be understood that a plurality of precoding matrices with equally-spaced index values are one precoding matrix subset. Precoding matrices with index values of 0, 4, 8, 12, 16, 20, 24 belong to the same subset of precoding matrices, or referred to as a first subset of precoding matrices; precoding matrices with index values of 1, 5, 9, 13, 17, 21, 25 belong to the same subset of precoding matrices, or referred to as a second subset of precoding matrices; precoding matrices with index values of 2, 6, 10, 14, 18, 22, 26 belong to the same subset of precoding matrices, or referred to as a third subset of precoding matrices; precoding matrices with index values 3, 7, 11, 15, 19, 23, 27 belong to the same subset of precoding matrices, or referred to as a fourth subset of precoding matrices.

The first relation may also have another expression, that is, when the first codebook is divided into a plurality of precoding matrix subsets, the first relation may be divided by a plurality of precoding matrices with adjacent index values, that is, each precoding matrix subset includes a plurality of precoding matrices with adjacent index values. The second relation may also have another expression, that is, when the first codebook is divided into a plurality of precoding matrix subsets, the plurality of precoding matrices may be divided by means of equally-spaced index values, that is, each precoding matrix subset includes a plurality of equally-spaced precoding matrices of the index values.

It should be noted that, when L may be divided by K, the number of precoding matrices included in different precoding matrix subsets in the first codebook is the same, and when L cannot be divided by K, the number of precoding matrices included in different precoding matrix subsets in the first codebook may be different, and further, there may be a case where only one precoding matrix exists in a certain precoding matrix subset, which is not limited in this aspect of the present application.

In yet another alternative, if the first codebook is a codebook generated based on DFT, at least two different precoding matrix subsets in the first codebook correspond to different column vectors in the DFT transformed matrix, that is, the plurality of precoding matrices in the first codebook are divided into a plurality of precoding matrix subsets by at least one column vector in the DFT transformed matrix. Column vectors in DFT transform matrices corresponding to different precoding matrix subsets are different.

For example, for a codebook generated based on DFT, the matrix generated by this method can be expressed as:wherein,u _m can be understood as a column in the DFT matrix where N ₁ And N ₂ The number of antenna ports in the horizontal dimension and the vertical dimension respectively, O ₁ And O ₂ Respectively isOversampling factors in the horizontal and vertical dimensions. In the codebook generation mode, the codebook generation mode mainly comprises beams with selected vertical positions and horizontal dimensions and phase offsets in different polarization directions, and v needs to be determined when constructing a precoding matrix subset _t,m And a phase θ, where each value of t corresponds to a beam (beam) in the horizontal direction and each value of m corresponds to a beam in the vertical direction.

For precoding matrix subset partitioning of a DFT-generated codebook, an alternative precoding matrix subset construction method can be expressed as: given a certain t and m, θ is variable. For example, when t and m take 1, θ takesYet another alternative precoding matrix subset construction method can be expressed as: the values of t and m are grouped, and each group of t, m and theta can form a precoding matrix set. For example, index t, t+O ₁ ,m,m+O ₂ The corresponding beams are divided into a group, and the indexes are t+1, t+1+O ₁ ,m+1,m+1+O ₂ The corresponding beams are grouped into a set, and so on, and in addition, the grouping in this example assumes m>1,t>1,O ₁ >1,O ₂ >1. The grouping method may be different when the above-mentioned parameters take other values.

S23: the network device sends downlink control information to the terminal device, where the downlink control information includes indexes of the N precoding matrix subsets. Correspondingly, the terminal equipment receives the downlink control information.

Specifically, the downlink control information includes indexes of N precoding matrix subsets, and optionally, the downlink control information may further include resource indication information of a first downlink reference signal, where the first downlink reference signal may be a channel state reference signal CSI-RS. The indexes of the N precoding matrix subsets may be indexes of different precoding matrix subsets, for example, the downlink control information indicates indexes of 5 precoding matrix subsets, and the 5 index values are 1, 2, 3, 4, and 5, respectively. There may also be indexes of the same precoding matrix subset, i.e. there may be the same index values in the indexes of the N precoding matrix subsets. For example, the downlink control information indicates indexes of 5 precoding matrix subsets, and the index values may be 1, 2, 3, and 4, respectively, that is, at this time, two precoding matrix subsets exist in the 5 precoding matrix subsets as the same precoding matrix subset.

S24: the terminal device determines at least N precoding matrices among the N precoding matrix subsets.

Specifically, the terminal device receives downlink control information, and determines at least N precoding matrices according to indexes of N precoding matrix subsets indicated by the downlink control information. When the downlink control information further includes resource indication information of the first downlink reference signal, the terminal device determines at least N precoding matrices according to indexes of N precoding matrix subsets indicated by the downlink control information and the first reference signal on the resource indication information. The resource corresponding to the resource indication information of the first reference signal may be a time domain resource, a frequency domain resource or a time-frequency resource.

S25: the terminal equipment transmits uplink signals based on at least N precoding matrixes, wherein N is a positive integer.

Specifically, the terminal device determines at least N precoding matrices, and transmits an uplink signal based on the at least N precoding matrices. Optionally, the uplink signal is a physical shared uplink channel PUSCH, and the PUSCH occupies a plurality of subbands. For a plurality of subbands, wherein each subband includes at least one RB or RBG, and the bandwidth of each subband is less than the bandwidth portion BWP. When each sub-band includes one RBG, the size of each sub-band is the same as that of the RBG, and at this time, since the number of RBs included in each BBG is related to the bandwidth part BWP, it can also be understood that the size of each sub-band is related to the bandwidth part BWP. When each sub-band contains a plurality of RBGs, the number of RBGs contained in each sub-band may be indicated by the indication information, and it may be understood that the size of each sub-band is independently configured regardless of the size of the bandwidth portion WBP. The indication information may be carried in DCI, RRC signaling, MAC CE, or RRC signaling and MCA CE, which is not limited in this aspect of the present application.

If the PUSCH occupies M subbands, each subband corresponds to one precoding matrix, the precoding matrices on different subbands may be the same or different, and further, the precoding matrices on different subbands may belong to the same subset of precoding matrices or different subsets of precoding matrices, that is, M is a positive integer greater than or equal to N.

In an example one, the number of precoding matrix subsets indicated by the downlink control information is N, where the N precoding matrix subsets are different from each other. The terminal equipment sends the PUSCH and occupies M sub-bands, M is equal to N, at the moment, the precoding matrixes corresponding to different sub-bands belong to different precoding matrix subsets, namely, the M precoding matrix subsets are in one-to-one correspondence with the M sub-bands, and further, when the precoding matrixes in the M precoding matrix subsets are different, the terminal equipment determines the M different precoding matrixes and the M sub-bands in one-to-one correspondence.

In example two, the number of precoding matrix subsets indicated by the downlink control information is N, where N precoding matrix subsets include N different precoding matrix subsets, and N is greater than N. The terminal device sends the PUSCH and occupies M subbands, M is greater than n, and at this time, in the M subbands, there are at least two precoding matrix subsets corresponding to the same subband, and further, the precoding matrices corresponding to the at least two subbands may be the same precoding matrix in the same precoding matrix subset, or may be different precoding matrices.

In the third example, the number of precoding matrix subsets indicated by the downlink control information is 1, that is, N is equal to 1, the PUSCH transmitted by the terminal device occupies M subbands, M is greater than N, where M subbands correspond to one precoding matrix subset, further, the precoding matrices corresponding to the M subbands may all be different, or there may be at least two precoding matrices corresponding to the same precoding matrix.

The above N precoding matrix subsets and the correspondence of the plurality of subbands are merely exemplary, and in the present application, for the plurality of subbands, each subband may correspond to any one precoding matrix in any one of the N precoding matrix subsets based on a capacity maximization principle, and the precoding matrices corresponding to different subbands may be the same or different, and the precoding matrices on different subbands may belong to the same precoding matrix subset or different precoding matrix subsets. The method and the device avoid the situation that when the terminal equipment can only use one precoding matrix to send uplink signals on M sub-bands, the one precoding matrix possibly cannot be matched with the reduction of frequency selection gain and the reduction of beam forming gain caused by channel change. Meanwhile, the network equipment indicates partial precoding matrix information to the terminal equipment, so that signaling overhead of sub-band level precoding can be reduced, complexity of detection of the terminal equipment is reduced, and transmission performance is improved.

In addition, in one embodiment, the downlink control information is further used for indicating an index of at least one precoding matrix, where the precoding matrix corresponding to the at least one precoding matrix index is a precoding matrix that is not expected to be used by the terminal device by the network device, or is understood to be a precoding matrix that is expected to be avoided by the terminal device by the network device. Optionally, the precoding matrix corresponding to the at least one precoding matrix index may be a precoding matrix of an interference channel, and further optionally, the interference channel may be an interference channel of a bandwidth part BWP. For example, the network device indicates the precoding matrix of the interference channel to the terminal device, when the terminal device determines at least N precoding matrices in the N precoding matrix subsets according to the downlink control information, the terminal device selects the precoding matrix with the lowest correlation with the precoding matrix of the interference channel in the N precoding matrix subsets, thereby avoiding the influence of the interference channel, so that the terminal device can better transmit uplink signals and improve the communication quality.

In the present application, the downlink control information is used as an example to indicate information, and in practical application, the content indicated by the downlink control information in the present application may be carried in DCI, or may be carried in RRC signaling or MAC CE, or the content indicated by the downlink control information itself may be indicated by the RRC signaling and MAC CE in combination, which is not limited by the present application.

Fig. 3 is a schematic hardware structure of a network device and a terminal device provided by the present application.

The terminal device 130 comprises at least one processor 301, at least one memory 302, at least one transceiver 303. Optionally, the terminal device 130 may further include an output device 304 and an input device 305.

The processor 301, the memory 302 and the transceiver 303 are connected by a bus. The processor 301 may be a general purpose central processing unit (Central Processing Unit, CPU), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of the program of the present application. Processor 301 may also include multiple CPUs, and processor 301 may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. A processor herein may refer to one or more devices, circuits, or processing cores for processing data (e.g., computer program instructions).

Memory 302 may be, but is not limited to, read-Only Memory (ROM) or other type of static storage device that can store static information and instructions, random access Memory (Random Access Memory, RAM) or other type of dynamic storage device that can store information and instructions, but may also be electrically erasable programmable Read-Only Memory (Electrically Erasable Programmable Read-Only Memory, EEPROM), compact disc Read-Only Memory (Compact Disc Read-Only Memory) or other optical disc storage, optical disc storage (including compact disc, laser disc, optical disc, digital versatile disc, blu-ray disc, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. The memory 302 may be stand alone and may be coupled to the processor 301 via a bus. Memory 302 may also be integrated with processor 301. The memory 302 is used for storing application program codes for executing the scheme of the application, and the execution is controlled by the processor 301. The processor 301 is configured to execute computer program code stored in the memory 302 to implement the method of cooperative transmission described in the embodiments of the present application.

The transceiver 303 may use any transceiver-like device for communicating with other devices or communication networks, such as ethernet, radio access network (Radio Access Network, RAN), wireless local area network (Wireless Local Area Networks, WLAN), etc. The transceiver 303 includes a transmitter Tx and a receiver Rx.

The output device 304 communicates with the processor 301 and may display information in a variety of ways. For example, the output device 304 may be a liquid crystal display (Liquid Crystal Display, LCD), a light emitting diode (Light Emitting Diode, LED) display device, a Cathode Ray Tube (CRT) display device, or a projector (projector), or the like. The input device 305 is in communication with the processor 301 and may receive user input in a variety of ways. For example, the input device 305 may be a mouse, a keyboard, a touch screen device, a sensing device, or the like.

The network device 120 includes at least one processor 201, at least one memory 202, at least one transceiver 203, and at least one network interface 204. The processor 201, the memory 202, the transceiver 203, and the network interface 204 are connected by a bus. The network interface 204 is used to connect with a core network device through a link (such as an S1 interface), or connect with a network interface of another access network device through a wired or wireless link (such as an X2 interface) (not shown in the figure), which is not limited in detail in the embodiment of the present application. In addition, the description of the processor 201, the memory 202 and the transceiver 203 may refer to the description of the processor 301, the memory 302 and the transceiver 303 in the terminal device 130, which are not repeated herein.

Fig. 4 is a schematic structural diagram of a possible communication device according to the present application. The communication apparatus 400 may implement the functions of the network device in the above-described method embodiment, and thus may also implement the beneficial effects of the above-described method embodiment. In the embodiment of the present application, the communication device may be the access network device 120 shown in fig. 1, or may be a module (such as a chip) applied to the access network device. The communication device 400 comprises a transceiver unit 401 and a processing unit 402.

Specifically, the processing unit 402 is configured to determine N precoding matrix subsets, where the N precoding matrix subsets are one or more of a plurality of precoding matrix subsets divided by the first codebook, and at least one precoding matrix subset among the N precoding matrix subsets includes at least two precoding matrices. The transceiver unit 401 is configured to send downlink control information to a terminal device, where the downlink control information includes indexes of N precoding matrix subsets. Optionally, the transceiver 401 is further configured to receive an uplink signal sent by the terminal device, where the uplink signal occupies M subbands, and the downlink control information further includes indication information of the M subbands, where the M subbands correspond to the N precoding matrices. For a specific description, reference may be made to the description of the method embodiments described above.

Fig. 5 is a schematic structural diagram of a possible communication device according to an embodiment of the present application. The communication device 500 may implement the functions of the terminal device in the above method embodiment, so that the beneficial effects of the above method embodiment may also be implemented. In the embodiment of the present application, the communication device may be the terminal device 110 shown in fig. 1, or may be a module (such as a chip) applied to the terminal device. The communication device 500 comprises a transceiver module 501 and a processing module 502.

Specifically, the transceiver module 501 is configured to receive downlink control information from a network device, where the downlink control information includes indexes of N precoding matrix subsets, where the N precoding matrix subsets are one or more of a plurality of precoding matrix subsets divided by a first codebook, and at least one precoding matrix subset includes at least two precoding matrices. The processing module 502 is configured to determine at least N precoding matrices from among the N precoding matrix subsets. The transceiver module 501 is further configured to send an uplink signal to the network device based on at least N precoding matrices.

Optionally, the downlink control information further includes resource indication information indicating the first downlink reference signal, and the terminal device determines at least N precoding matrices among the N precoding matrix subsets based on the first downlink reference signal on the resource indicated by the resource indication information.

The uplink signal is PUSCH, the PUSCH occupies M subbands, the M subbands correspond to N precoding matrix subsets, each subband in the M subbands corresponds to one precoding matrix, different precoding matrix subsets corresponding to different subbands can correspond to different precoding matrices in the same precoding matrix subset, and can also correspond to the same precoding matrix in the same precoding matrix subset:

in example one, M is equal to N, M subbands are in one-to-one correspondence with N different subsets of precoding matrices, and M subbands are in one-to-one correspondence with N precoding matrices in the N subsets of precoding matrices.

In example two, M is greater than N, M subbands correspond to N different sets of precoding codons, i.e., there are two or more subbands corresponding to the same set of precoding codons. At this time, the precoding matrices corresponding to two or more subbands corresponding to the same subset of precoding matrices may be the same or different.

In example three, N is equal to 1, M subbands correspond to M precoding matrices in one precoding subset, where the M precoding matrices may be M different precoding matrices, or two or more identical precoding matrices may exist.

For a more detailed description of the transceiver unit 401, transceiver module 501, processing unit 402 and processing module 502, reference is made to the relevant description of the method embodiments described above, which is not described here. The hardware elements of the transceiver unit 401 or the transceiver module 501 may be transceivers, and the hardware elements of the processing unit 402 or the processing module 502 may be processors.

Fig. 6 is a schematic structural diagram of a possible communication device provided by the present application, and a communication device 600 includes a processor 601 and an interface circuit 602. The processor 601 and the interface circuit 602 may be connected by a bus 603. It is understood that the interface circuit 602 may be a transceiver or an input-output interface. Optionally, the communication device 600 may further comprise a memory for storing instructions executed by the processor 601 or for storing input data required by the processor 601 to execute instructions or for storing data generated after the processor 601 executes instructions.

When the communication device 600 is used to implement the method in the above-described method embodiment, the processor 601 is configured to perform the functions of the processing unit 402 or the processing module 502, and the interface circuit 602 is configured to perform the functions of the transceiver unit 401 or the transceiver module 501.

When the communication apparatus 600 is a chip applied to a terminal device, the terminal device chip implements the functions of the terminal device in the above method embodiment. The terminal device chip receives information from other modules (such as a radio frequency module or an antenna) in the terminal device, and the information is sent to the terminal device by the network device; alternatively, the terminal device chip sends information to other modules (e.g., radio frequency modules or antennas) in the terminal device, which is sent by the terminal device to the network device.

When the communication apparatus 600 is a chip applied to a network device, the network device chip implements the functions of the network device in the method embodiment. The network device chip receives information from other modules (such as a radio frequency module or an antenna) in the network device, and the information is sent to the network device by the terminal device; alternatively, the network device chip sends information to other modules (e.g., radio frequency modules or antennas) in the network device, which the network device sends to the terminal device.

It is to be appreciated that the processor in embodiments of the application may be a central processing unit (central processing unit, CPU), other general purpose processor, digital signal processor (digital signal processor, DSP), application specific integrated circuit (application specific integrated circuit, ASIC), field programmable gate array (field programmable gate array, FPGA) or other programmable logic device, transistor logic device, hardware components, or any combination thereof. The general purpose processor may be a microprocessor, but in the alternative, it may be any conventional processor.

In the embodiment of the application, the terminal equipment or the network equipment comprises a hardware layer, an operating system layer running on the hardware layer and an application layer running on the operating system layer. The hardware layer includes hardware such as a central processing unit (central processing unit, CPU), a memory management unit (memory management unit, MMU), and a memory (also referred to as a main memory). The operating system may be any one or more computer operating systems that implement business processes through processes (processes), such as a Linux operating system, a Unix operating system, an Android operating system, an iOS operating system, or a windows operating system. The application layer comprises applications such as a browser, an address book, word processing software, instant messaging software and the like. Further, the embodiment of the present application is not particularly limited to the specific structure of the execution body of the method provided by the embodiment of the present application, as long as the communication can be performed by the method provided according to the embodiment of the present application by running the program recorded with the code of the method provided by the embodiment of the present application, and for example, the execution body of the method provided by the embodiment of the present application may be a terminal device or a network device, or a functional module in the terminal device or the network device that can call the program and execute the program.

Furthermore, various aspects or features of the application may be implemented as a method, apparatus, or article of manufacture using standard programming and/or engineering techniques. The term "article of manufacture" as used herein encompasses a computer program accessible from any computer-readable device, carrier, or media. For example, computer-readable media can include, but are not limited to, magnetic storage devices (e.g., hard disk, floppy disk, or magnetic strips, etc.), optical disks (e.g., compact disk, CD, digital versatile disk, digital versatile disc, DVD, etc.), smart cards, and flash memory devices (e.g., erasable programmable read-only memory, EPROM), cards, sticks, or key drives, etc. Additionally, various storage media described herein can represent one or more devices and/or other machine-readable media for storing information. The term "machine-readable medium" can include, without being limited to, wireless channels and various other media capable of storing, containing, and/or carrying instruction(s) and/or data.

It should be noted that the memory of the systems and methods described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

The present application also provides a computer program product comprising: computer program code which, when run on a computer, causes the computer to perform the method performed by the terminal device or the network device in any of the method embodiments described above.

The present application also provides a computer readable storage medium storing program code which, when run on a computer, causes the computer to perform the method performed by the network device or the terminal device in the foregoing method embodiments.

The application also provides a system comprising at least one terminal device and at least one network device.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, the processes or functions described in accordance with embodiments of the present application are produced in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by a wired (e.g., coaxial cable, fiber optic, digital subscriber line (digital subscriber line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that contains an integration of one or more available media. The usable medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a high-density digital video disc (digital video disc, DVD)), or a semiconductor medium (e.g., a Solid State Disk (SSD)), or the like.

As used in this specification, the terms "component," "module," "system," and the like are intended to refer to a computer-related entity, either hardware, firmware, a combination of hardware and software, or software in execution. For example, a component may be, but is not limited to being, a process running on a processor, an object, an executable, a thread of execution, a program, or a computer. By way of illustration, both an application running on a computing device and the computing device can be a component. One or more components may reside within a process or thread of execution and a component may be localized on one computer or distributed between 2 or more computers. Furthermore, these components can execute from various computer readable media having various data structures stored thereon. The components may communicate by way of local or remote processes such as in accordance with a signal having one or more data packets (e.g., data from two components interacting with one another in a local system, distributed system, or across a network such as the internet with other systems by way of the signal).

It should be appreciated that reference throughout this specification to "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present application. Thus, various embodiments are not necessarily referring to the same embodiments throughout the specification. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

It should be understood that, in the embodiment of the present application, the numbers "first" and "second" … are merely for distinguishing different objects, for example, for distinguishing different network devices, and are not limited to the scope of the embodiment of the present application, but the embodiment of the present application is not limited thereto.

It should also be understood that, in the present application, "when …", "if" and "if" all refer to the corresponding processing that the network element will make under some objective condition, and are not limited in time, nor do they require that the network element must have a judging action when implemented, nor are other limitations meant to be present.

It should also be understood that in the present application, "at least one" means one or more, and "a plurality" means two or more.

It should also be understood that in embodiments of the present application, "B corresponding to A" means that B is associated with A from which B may be determined. It should also be understood that determining B from a does not mean determining B from a alone, but may also determine B from a and/or other information.

It should also be understood that the term "and/or" is merely one association relationship describing the associated object, and means that three relationships may exist, for example, a and/or B may mean: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

Items appearing in the present application that are similar to "include one or more of the following: the meaning of the expressions a, B, and C "generally means that the item may be any one of the following unless otherwise specified: a, A is as follows; b, a step of preparing a composite material; c, performing operation; a and B; a and C; b and C; a, B and C; a and A; a, A and A; a, A and B; a, a and C, a, B and B; a, C and C; b and B, B and C, C and C; c, C and C, and other combinations of a, B and C. The above is an optional entry for the item exemplified by 3 elements a, B and C, when expressed as "the item includes at least one of the following: a, B, … …, and X ", i.e. when there are more elements in the expression, then the entry to which the item is applicable can also be obtained according to the rules described above.

It will be understood that, in the embodiments of the present application, the terminal device and/or the network device may perform some or all of the steps in the embodiments of the present application, these steps or operations are merely examples, and the embodiments of the present application may also perform other operations or variations of the various operations. Furthermore, the various steps may be performed in a different order presented in accordance with embodiments of the application, and it is possible that not all of the operations in the embodiments of the application may be performed.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It will be clear to those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described systems, apparatuses and units may refer to corresponding procedures in the foregoing method embodiments, and are not repeated herein.

In the several embodiments provided by the present application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit.

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application may be embodied essentially or in a part contributing to the prior art or in a part of the technical solution, in the form of a software product stored in a storage medium, comprising several instructions for causing a computer device (which may be a personal computer, a server, a network device, etc.) to perform all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: a usb disk, a removable hard disk, a ROM, a RAM, a magnetic disk, or an optical disk, or other various media capable of storing program codes.

The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

A method of communication, the method comprising:

receiving downlink control information from network equipment, wherein the downlink control information comprises indexes of N precoding matrix subsets, the N precoding matrix subsets are one or more of a plurality of precoding matrix subsets divided by a first codebook, and at least one precoding matrix subset in the N precoding matrix subsets comprises at least two precoding matrices;

determining at least N precoding matrices from the N precoding matrix subsets;

and transmitting uplink signals based on the at least N precoding matrixes, wherein N is a positive integer.
The method of claim 1, wherein the downlink control information further comprises: resource indication information for indicating the first downlink reference signal;

The determining at least N precoding matrices among the N precoding matrices includes: and determining at least N precoding matrixes in the N precoding matrix subsets based on the first downlink reference signals on the resources indicated by the resource indication information.
The method of claim 1 or 2, wherein the uplink signal is a physical uplink shared channel PUSCH, the PUSCH occupies N subbands, the downlink control information further includes indication information of the N subbands, the at least N precoding matrices are N, the N precoding matrix subsets are in one-to-one correspondence with the N subbands, and the N precoding matrices are in one-to-one correspondence with the N subbands;

the transmitting uplink signals based on the N precoding matrices includes: and transmitting the PUSCH on the N sub-bands based on the N precoding matrixes.
The method of claim 1 or 2, wherein the uplink signal is a physical uplink shared channel PUSCH, the N precoding matrix subsets are one precoding matrix subset, and the PUSCH occupies M subbands;

the determining at least N precoding matrices in the N precoding matrix subsets includes: determining M precoding matrixes in the precoding matrix subset, wherein the M precoding matrixes are in one-to-one correspondence with the M sub-bands;

The transmitting uplink signals based on the N precoding matrices includes: and transmitting the PUSCH on the M sub-bands based on the M precoding matrices.
The method of any of claims 1-4, wherein at least two different ones of the plurality of precoding matrix subsets correspond to different values of the first codebook parameter, the first codebook parameter comprising a phase.
The method of any of claims 1-4, wherein the plurality of precoding matrix subsets is K, the first codebook contains L precoding matrices, and an index of a precoding matrix included in each of the plurality of precoding matrix subsets satisfies:or mod (j, K), where j is the index of each precoding matrix in the first codebook,in order to lower the round-down function,is a top-rounding function.
The method of any of claims 1-4, wherein the first codebook is generated based on a discrete fourier transform matrix, at least two different ones of the plurality of precoding matrix subsets corresponding to different column vectors in the discrete fourier transform matrix.
The method of any one of claims 1-7, wherein the downlink control information further comprises: and an index of at least one precoding matrix, the at least one precoding matrix being a precoding matrix not intended for the terminal equipment.
A method of communication, the method comprising:

determining N precoding matrix subsets;

and sending downlink control information to the terminal equipment, wherein the downlink control information comprises indexes of N precoding matrix subsets, the N precoding matrix subsets are one or more of a plurality of precoding matrix subsets divided by a first codebook, and at least one precoding matrix subset in the N precoding matrix subsets comprises at least two precoding matrices.
The method of claim 9, wherein the downlink control information further comprises: and the resource indication information is used for indicating a first downlink reference signal, and the downlink reference signal is used for determining at least N precoding matrixes in the N precoding matrix subsets by the terminal equipment.
The method of claim 9 or 10, wherein the at least N precoding matrices correspond to M subbands, M being greater than or equal to N, the method further comprising: and receiving uplink signals on the M sub-bands, wherein the uplink signals are Physical Uplink Shared Channels (PUSCHs).
The method according to claim 10 or 11, wherein the at least N precoding matrices belong to M different subsets of precoding matrices or the at least N precoding matrices belong to the same subset of precoding matrices.
The method according to any of claims 9-12, wherein at least two different ones of the plurality of precoding matrix subsets correspond to different values of the first codebook parameter, the first codebook parameter comprising a phase.
The method according to any of claims 9-12, wherein the plurality of precoding matrix subsets is K, the first codebook contains L precoding matrices, and each precoding matrix subset in the plurality of precoding matrix subsets includes a precoding matrix satisfying:or mod (j, K), where j is the index of each precoding matrix in the first codebook,in order to lower the round-down function,is a top-rounding function.
The method of any of claims 9-12, wherein the first codebook is generated based on a discrete fourier transform matrix, at least two different ones of the plurality of precoding matrix subsets corresponding to different column vectors in the discrete fourier transform matrix.
The method of any one of claims 9-15, wherein the downlink control information further comprises: and an index of at least one precoding matrix, the at least one precoding matrix being a precoding matrix not intended for the terminal equipment.
A communication device, the device comprising:

a receiving unit, configured to receive downlink control information from a network device, where the downlink control information includes indexes of N precoding matrix subsets, where the N precoding matrix subsets are one or more of a plurality of precoding matrix subsets divided by a first codebook, and at least one precoding matrix subset of the N precoding matrix subsets includes at least two precoding matrices;

a processing unit, configured to determine at least N precoding matrices from the N precoding matrix subsets;

and the sending unit is used for sending the uplink signals based on the at least N precoding matrixes, wherein N is a positive integer.
The communications apparatus of claim 17, wherein the downlink control information further comprises: resource indication information for indicating the first downlink reference signal;

the determining at least N precoding matrices among the N precoding matrices includes: and determining at least N precoding matrixes in the N precoding matrix subsets based on the first downlink reference signals on the resources indicated by the resource indication information.
The communications apparatus of claim 17 or 18, wherein the uplink signal is a physical uplink shared channel, PUSCH, the PUSCH occupies N subbands, the downlink control information further includes indication information for the N subbands, the N precoding matrix subsets are in one-to-one correspondence with the N subbands, and the N precoding matrices are in one-to-one correspondence with the N subbands;

the transmitting uplink signals based on the N precoding matrices includes: and transmitting the PUSCH on the N sub-bands based on the N precoding matrixes.
The communications apparatus of claim 17 or 18, wherein the uplink signal is a physical uplink shared channel, PUSCH, the N precoding matrix subsets are one precoding matrix subset, and the PUSCH occupies M subbands;

the determining at least N precoding matrices in the N precoding matrix subsets includes: determining M precoding matrixes in the precoding matrix subset, wherein the M precoding matrixes are in one-to-one correspondence with the M sub-bands;

the transmitting uplink signals based on the N precoding matrices includes: and transmitting the PUSCH on the M sub-bands based on the M precoding matrices.
The communications apparatus of any of claims 17-20, wherein at least two different ones of the plurality of precoding matrix subsets correspond to different values of the first codebook parameter, the first codebook parameter comprising a phase.
The communications apparatus of any one of claims 17-20, wherein the plurality of precoding matrix subsets is K, the first codebook comprises L precoding matrices, and each precoding matrix subset of the plurality of precoding matrix subsets includes a precoding matrix that satisfies:or mod (j, K), where j is the index of each precoding matrix in the first codebook,in order to lower the round-down function,is a top-rounding function.
The communications apparatus of any of claims 17-20, wherein the first codebook is generated based on a discrete fourier transform matrix, at least two different ones of the plurality of precoding matrix subsets corresponding to different column vectors in the discrete fourier transform matrix.
The communication apparatus according to any one of claims 17-23, wherein the downlink control information further comprises: and an index of at least one precoding matrix, the at least one precoding matrix being a precoding matrix not intended for the terminal equipment.
A communication device, the communication device comprising:

a processing unit, configured to determine N precoding matrix subsets;

a sending unit, configured to send downlink control information to a terminal device, where the downlink control information includes indexes of N precoding matrix subsets, where the N precoding matrix subsets are one or more of a plurality of precoding matrix subsets divided by a first codebook, and at least one precoding matrix subset of the N precoding matrix subsets includes at least two precoding matrices.
The communications apparatus of claim 25, wherein the downlink control information further comprises: and the resource indication information is used for indicating a first downlink reference signal, and the downlink reference signal is used for determining at least N precoding matrixes in the N precoding matrix subsets by the terminal equipment.
The communications apparatus of claim 25 or 26, wherein the at least N precoding matrices are in one-to-one correspondence with at least N subbands, the communications apparatus further comprising: and the receiving unit is used for receiving uplink signals on the at least N sub-bands, wherein the uplink signals are Physical Uplink Shared Channels (PUSCHs).
The communications apparatus of claim 26 or 27, wherein the at least N precoding matrices belong to M different subsets of precoding matrices or the at least N precoding matrices belong to the same subset of precoding matrices.
The communications apparatus of any of claims 25-28, wherein at least two different ones of the plurality of precoding matrix subsets correspond to different values of the first codebook parameter, the first codebook parameter comprising a phase.
The communications apparatus of any one of claims 25-28, wherein the plurality of precoding matrix subsets is K, the first codebook comprises L precoding matrices, and each precoding matrix subset of the plurality of precoding matrix subsets comprises a precoding matrix that satisfies:or mod (j, K), where j is the index of each precoding matrix in the first codebook,in order to lower the round-down function,is a top-rounding function.
The communications apparatus of any of claims 25-28, wherein the first codebook is generated based on a discrete fourier transform matrix, at least two different ones of the plurality of precoding matrix subsets corresponding to different column vectors in the discrete fourier transform matrix.
The method of any one of claims 25-31, wherein the downlink control information further comprises: and an index of at least one precoding matrix, the at least one precoding matrix being a precoding matrix not intended for the terminal equipment.
A communication device, comprising: at least one processor and interface circuitry to provide input or output of instructions and/or data to the at least one processor, which when executed causes the apparatus to implement the method of any of claims 1-8 or 9-16.
A computer readable storage medium comprising a program or instructions which, when run on a computer, performs the method of any of claims 1-8 or claims 9-16.