Communication method and apparatus

Abstract

The present application relates to the technical field of communications, and provides a communication method and apparatus. The method comprises: a network device determines L demodulation reference signal (DMRS) antenna ports from among N DMRS antenna ports, wherein the N DMRS antenna ports are used for physical downlink control channel (PDCCH) transmission, and any two of the N DMRS antenna ports are orthogonally multiplexed by means of at least one of the following: time division multiplexing (TDM), frequency division multiplexing (FDM), or code division multiplexing (CDM); N is a positive integer greater than or equal to 2, and L is a positive integer less than or equal to N; and the network device sends a DMRS of a first PDCCH by means of the L DMRS antenna ports.

Description

Communication method and device

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on November 30, 2023, with application number 202311637463.4 and invention name “A Communication Method and Device”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of communication technology, and in particular to a communication method and device. Background Art

[0003] With the development of communication technology, multi-user multiple-input multiple-output (MU-MIMO) technology has been proposed in new radio (NR) communication systems. This technology allows multiple terminal devices to communicate with network devices on the same time-frequency resources, and multiple terminal devices share the same time-frequency resources through space division.

[0004] However, when multiple physical downlink control channels (PDCCHs) are transmitted using MU-MIMO, the demodulation reference signals (DMRSs) of the multiple PDCCHs may not be orthogonal, which limits the PDCCH demodulation performance and affects the PDCCH capacity.

[0005] Summary of the Invention

[0006] In order to solve the above technical problems, this application provides a communication method and apparatus that can improve PDCCH demodulation performance and capacity. To achieve the above objectives, this application adopts the following technical solutions:

[0007] In a first aspect, a communication method is provided. The method can be executed by a network device. Unless otherwise specified, the "network device" in this application can refer to the network device itself, or a component in the network device (for example, a processor, a chip, or a chip system, etc.), or a logic module or software that can implement all or part of the network device functions. The following description is based on the example of the execution subject being the network device. The method includes:

[0008] The network device determines L demodulation reference signal (DMRS) antenna ports from N DMRS antenna ports, where the N DMRS antenna ports are used for physical downlink control channel (PDCCH) transmission. Any two of the N DMRS antenna ports are orthogonally multiplexed using at least one of the following: time division multiplexing (TDM), frequency division multiplexing (FDM), or code division multiplexing (CDM). N is a positive integer greater than or equal to 2, and L is a positive integer less than or equal to N. The network device transmits a DMRS for a first PDCCH via the L DMRS antenna ports.

[0009] The TDM between any two DMRS antenna ports means that different DMRS antenna ports are associated with or use different time domain resources. In this way, the PDCCH DMRS transmitted on different DMRS antenna ports can use different time domain resources, thereby ensuring that the DMRSs of different PDCCHs are orthogonal to each other.

[0010] The FDM between any two DMRS antenna ports means that different DMRS antenna ports are associated with or use different frequency domain resources. In this way, the PDCCH DMRS transmitted on different DMRS antenna ports can use different frequency domain resources, thereby ensuring that the DMRSs of different PDCCHs are orthogonal to each other.

[0011] The CDM between any two DMRS antenna ports means that different DMRS antenna ports are associated or use different orthogonal masks (OCCs). In this way, PDCCH DMRS transmitted on different DMRS antenna ports can use different orthogonal masks, thereby ensuring that the DMRSs of different PDCCHs are orthogonal to each other.

[0012] Among them, for the DMRS of the first PDCCH, the network device sends the DMRS of the first PDCCH through the L DMRS antenna ports, including: the network device sends the DMRS of the first PDCCH through at least one of the time domain resources, frequency domain resources, or orthogonal mask codes OCC associated with the L DMRS antenna ports, and the L DMRS antenna ports.

[0013] In addition, the first PDCCH also includes data information. With respect to the data information of the first PDCCH, the network device sends the data information of the first PDCCH through the L DMRS antenna ports, including: the network device sends the data information of the first PDCCH through the L antenna ports instead of using any one of time domain resources, frequency domain resources, and OCC associated with the L DMRS antenna ports to send the data information of the first PDCCH.

[0014] Optionally, corresponding to L being less than N, the network device may further perform the following operation: the network device determines L' DMRS antenna ports from the N DMRS antenna ports, where any one of the L' DMRS antenna ports is different from any one of the L DMRS antenna ports. L' is a positive integer less than or equal to N. The network device transmits a DMRS of a second PDCCH through the L' DMRS antenna ports. The second PDCCH is different from the first PDCCH.

[0015] In this way, since the N DMRS antenna ports can be used for PDCCH transmission and the N DMRS antenna ports are orthogonal to each other, when different PDCCH DMRS are transmitted through different DMRS antenna ports among the N DMRS antenna ports, the DMRS of different PDCCHs are orthogonal to each other. For example, the DMRS of the first PDCCH is orthogonal to the DMRS of other PDCCHs, which helps to improve the PDCCH demodulation performance and PDCCH capacity and ensure PDCCH performance.

[0016] In one possible design, when orthogonal multiplexing is performed between any two of the N DMRS antenna ports through the CDM, different frequency domain orthogonal masks OCC and / or different time domain OCCs are associated between any two of the N DMRS antenna ports, so that any two DMRS antenna ports are orthogonal to each other.

[0017] In one possible design, when orthogonal multiplexing is performed between any two DMRS antenna ports among the N DMRS antenna ports through the CDM and the FDM:

[0018] The N DMRS antenna ports belong to at least two CDM groups, and each of the at least two CDM groups includes a portion of the N DMRS antenna ports. The number of DMRS antenna ports included in different CDM groups in the at least two CDM groups may be the same or different.

[0019] Different frequency domain OCCs and / or different time domain OCCs are associated between any two DMRS antenna ports in any one of the at least two CDM groups, so that any two DMRS antenna ports in each CDM group are orthogonal to each other.

[0020] Different frequency domain resources are associated between any two CDM groups in the at least two CDM groups, so that any two DMRS antenna ports between different CDM groups are orthogonal to each other.

[0021] In one possible design, the transmission resources of the first PDCCH include multiple resource element groups (REGs), each of the multiple REGs includes M first resource elements (REs), and the M first REGs are used to carry DMRSs of the PDCCH, where M is a positive integer greater than 3. Each of the multiple REGs includes one orthogonal frequency division multiplexing (OFDM) symbol in the time domain and one resource block (RB) in the frequency domain.

[0022] For example, M is an even number, M=4.

[0023] In this way, the N DMRS antenna ports can support the associated frequency domain OCC, avoid excessive DMRS overhead, and ensure DMRS performance.

[0024] In one possible design, the time domain resources of the first PDCCH include K symbols, where the K symbols include a first symbol and a second symbol. K is a positive integer greater than or equal to 2. The first PDCCH includes data information of the first PDCCH and a DMRS of the first PDCCH. The data information of the first PDCCH occupies the first symbol, and the DMRS of the first PDCCH occupies the second symbol. That is, the data information of the first PDCCH and the DMRS of the first PDCCH are transmitted using a time-division multiplexing (TDM) scheme.

[0025] In one possible design, the length of the frequency domain OCC is 2 or 4, and the length of the time domain OCC is 2 or 4.

[0026] In one possible design, the value of N includes 2 T Or 3*Q, where T and Q are positive integers.

[0027] For example, the value of N includes one of the following: 2, 3, 4, 6, 8, 12, or 16.

[0028] In one possible design, the method further includes: the network device sending first information. The first information indicates the L antenna ports. The first information is carried in one of the following: radio resource control RRC signaling, system broadcast information block SIB, downlink control information DCI, or media access control layer control element MAC CE.

[0029] That is, the network device indicates to the first terminal device: through which DMRS antenna port(s) the first PDCCH is detected, so as to simplify the computational complexity on the terminal device side.

[0030] In one possible design, the first information indicates the L antenna ports, including: the first information indicates that the first terminal device uses the L DMRS antenna ports on the first search space set SS set to detect the first PDCCH.

[0031] The first SS set is all SS sets associated with all control resource sets CORESET of the first terminal device. That is, the network device indicates the DMRS antenna port at the terminal device granularity through the first information.

[0032] Alternatively, the first SS set is all SS sets associated with all CORESETs on the first bandwidth part BWP, and the first BWP is one of all BWPs of the first terminal device. That is, the network device indicates the DMRS antenna port at BWP granularity through the first information.

[0033] Alternatively, the first SS set is all SS sets associated with the first CORESET, and the first CORESET is one CORESET among all CORESETs of the first terminal device. That is, the network device indicates the DMRS antenna port at a CORESET granularity through the first information.

[0034] Alternatively, the first SS set is one of all SS sets of the first terminal device. That is, the network device indicates the DMRS antenna port at an SS set granularity through the first information.

[0035] In one possible design, the first information indicating the L antenna ports includes: the first information instructing the first terminal device to use the L DMRS antenna ports to detect the first PDCCH on all SS sets associated with a first CORESET group, where the first CORESET group is one of all CORESET groups of the first terminal device. That is, the network device indicates the DMRS antenna ports at a CORESET group granularity through the first information.

[0036] In one possible design, the first information indicating the L antenna ports includes: the first information instructing a first terminal device to use the L DMRS antenna ports on a first SS set group to detect the first PDCCH, where the first SS set group is one of all SS set groups of the first terminal device. That is, the network device indicates the DMRS antenna ports at an SS set group granularity through the first information.

[0037] In one possible design, the DCI corresponds to a first terminal device group, where the first terminal device group includes at least one terminal device. The first information is carried in a first information block of the DCI, where the first information block corresponds to one or more terminal devices in the first terminal device group, where the one or more terminal devices include the first terminal device.

[0038] That is, the network device indicates DMRS antenna ports for different terminal devices through the same DCI.

[0039] In one possible design, the L DMRS antenna ports are determined based on the radio network temporary identifier RNTI of the first terminal device, such as the cell radio network temporary identifier C-RNTI of the first terminal device.

[0040] For example, L=1. The numbering of the L DMRS antenna ports satisfies: n RNTI mod N. Where n RNTI Indicates the value of the RNTI, where mod is a modulo operation.

[0041] In one possible design, the L DMRS antenna ports are determined based on a radio network temporary identifier RNTI of the first terminal device and a number of the first time unit. For example, the RNTI of the first terminal device may be a C-RNTI.

[0042] For example, L=1. The numbering of the L DMRS antenna ports satisfies: Y -1 =n RNTI Among them, n RNTI represents the value of the RNTI, represents the number of the first time unit, A and D are positive integers, and mod is a modulo operation.

[0043] In one possible design, the L DMRS antenna ports are determined based on a radio network temporary identifier (RNTI) of the first terminal device, a number of the first time unit, and a number of the first CORESET. For example, the RNTI of the first terminal device may be a C-RNTI.

[0044] For example, L=1. The numbering of the L DMRS antenna ports satisfies: Y p,-1 =n RNTI Among them, n RNTI represents the value of the RNTI, represents the number of the first time unit, p represents the number of the first CORESET, D is a positive integer, Ap It is a positive integer determined according to p, and mod is the modulo operation.

[0045] In a second aspect, a communication method is provided. The method can be executed by a first terminal device. Unless otherwise specified, the "first terminal device" in this application can refer to the first terminal device itself, or a component in the first terminal device (for example, a processor, a chip, or a chip system, etc.), or a logic module or software that can implement all or part of the functions of the first terminal device. Below, the execution subject is described as the first terminal device. The method includes: the first terminal device determines L demodulation reference signal DMRS antenna ports, the L DMRS antenna ports are one or more DMRS antenna ports among N DMRS antenna ports, the N DMRS antenna ports are used for physical downlink control channel PDCCH transmission, and any two DMRS antenna ports among the N DMRS antenna ports are orthogonally multiplexed by at least one of the following: time division multiplexing TDM, frequency division multiplexing FDM, or code division multiplexing CDM. N is a positive integer greater than or equal to 2, and L is a positive integer less than or equal to N. The first terminal device receives the DMRS of the first PDCCH through the L DMRS antenna ports.

[0046] In one possible design, when orthogonal multiplexing is performed between any two of the N DMRS antenna ports through the CDM, different frequency domain orthogonal masks OCC and / or different time domain OCCs are associated between any two of the N DMRS antenna ports, so that any two DMRS antenna ports are orthogonal to each other.

[0047] In one possible design, when orthogonal multiplexing is performed between any two DMRS antenna ports among the N DMRS antenna ports through the CDM and the FDM:

[0048] The N DMRS antenna ports belong to at least two CDM groups, and each of the at least two CDM groups includes a portion of the N DMRS antenna ports. The number of DMRS antenna ports included in different CDM groups in the at least two CDM groups may be the same or different.

[0049] Different frequency domain OCCs and / or different time domain OCCs are associated between any two DMRS antenna ports in any one of the at least two CDM groups, so that any two DMRS antenna ports in each CDM group are orthogonal to each other.

[0050] Different frequency domain resources are associated between any two CDM groups in the at least two CDM groups, so that any two DMRS antenna ports between different CDM groups are orthogonal to each other.

[0051] In one possible design, the transmission resources of the first PDCCH include multiple resource element groups (REGs), each of the multiple REGs includes M first resource elements (REs), and the M first REGs are used to carry DMRSs of the PDCCH, where M is a positive integer greater than 3. Each of the multiple REGs includes one orthogonal frequency division multiplexing (OFDM) symbol in the time domain and one resource block (RB) in the frequency domain.

[0052] For example, M is an even number, M=4.

[0053] In one possible design, the time domain resources of the first PDCCH include K symbols, where the K symbols include a first symbol and a second symbol. K is a positive integer greater than or equal to 2. The first PDCCH includes data information of the first PDCCH and a DMRS of the first PDCCH. The data information of the first PDCCH occupies the first symbol, and the DMRS of the first PDCCH occupies the second symbol.

[0054] In one possible design, the length of the frequency domain OCC is 2 or 4, and the length of the time domain OCC is 2 or 4.

[0055] In one possible design, the value of N includes 2 T Or 3*Q, where T and Q are positive integers.

[0056] For example, the value of N includes one of the following: 2, 3, 4, 6, 8, 12, or 16.

[0057] In one possible design, the method further includes: the first terminal device receiving first information. The first information indicates the L antenna ports. The first information is carried in one of the following: radio resource control RRC signaling, system broadcast information block SIB, downlink control information DCI, or media access control layer control element MAC CE.

[0058] In one possible design, the first information indicates the L antenna ports, including: the first information indicates that the first terminal device uses the L DMRS antenna ports on a first search space set SS set to detect the first PDCCH.

[0059] The first SS set is all SS sets associated with all control resource sets CORESET of the first terminal device.

[0060] Alternatively, the first SS set is all SS sets associated with all CORESETs on the first bandwidth part BWP, and the first BWP is one BWP among all BWPs of the first terminal device.

[0061] Alternatively, the first SS set is all SS sets associated with the first CORESET, and the first CORESET is one CORESET among all CORESETs of the first terminal device.

[0062] Alternatively, the first SS set is one SS set among all SS sets of the first terminal device.

[0063] In one possible design, the first information indicates the L antenna ports, including: the first information indicates that the first terminal device uses the L DMRS antenna ports to detect the first PDCCH on all SS sets associated with the first CORESET group, and the first CORESET group is one CORESET group among all CORESET groups of the first terminal device.

[0064] In one possible design, the first information indicates the L antenna ports, including: the first information indicates that the first terminal device uses the L DMRS antenna ports on a first SS set group to detect the first PDCCH, and the first SS set group is one of all SS set groups of the first terminal device.

[0065] In one possible design, the DCI corresponds to a first terminal device group, where the first terminal device group includes at least one terminal device. The first information is carried in a first information block of the DCI, where the first information block corresponds to one or more terminal devices in the first terminal device group, where the one or more terminal devices include the first terminal device.

[0066] In one possible design, the L DMRS antenna ports are determined based on the radio network temporary identifier RNTI of the first terminal device.

[0067] For example, L=1. The numbering of the L DMRS antenna ports satisfies: n RNTI mod N. Where n RNTI Indicates the value of the RNTI.

[0068] In one possible design, the L DMRS antenna ports are determined based on the radio network temporary identifier RNTI of the first terminal device and the number of the first time unit.

[0069] For example, L=1. The numbering of the L DMRS antenna ports satisfies: Y -1 =n RNTI Among them, n RNTI represents the value of the RNTI, represents the number of the first time unit, where A and D are positive integers.

[0070] In one possible design, the L DMRS antenna ports are determined based on the radio network temporary identifier RNTI of the first terminal device, the number of the first time unit, and the number of the first CORESET.

[0071] For example, L=1. The numbering of the L DMRS antenna ports satisfies: Y p,-1 =n RNTI Among them, n RNTI represents the value of the RNTI, represents the number of the first time unit, p represents the number of the first CORESET, D is a positive integer, A p is a positive integer determined according to p.

[0072] Among them, the technical effects brought about by the second aspect or any design method in the second aspect can refer to the technical effects brought about by different design methods in the first aspect, and will not be repeated here.

[0073] In a third aspect, a communication device is provided for implementing the various methods described above. The communication device includes modules, units, or means corresponding to the methods. The modules, units, or means may be implemented in hardware, software, or by hardware executing corresponding software implementations. The hardware or software includes one or more modules or units corresponding to the functions.

[0074] In some possible designs, the communication device may include a processing module and a transceiver module. The processing module may be used to implement the processing functions in any of the above aspects and any possible implementations thereof. The transceiver module, also referred to as a transceiver unit, is used to implement the sending and / or receiving functions in any of the above aspects and any possible implementations thereof. The transceiver module may be composed of a transceiver circuit, a transceiver, a transceiver, or a communication interface.

[0075] In some possible designs, the transceiver module includes a sending module and / or a receiving module, which are used to implement the sending or receiving functions in any of the above aspects and any possible implementation methods.

[0076] In a fourth aspect, a communication device is provided, comprising: a processor and a memory, wherein the processor and the memory are coupled, and the memory stores program instructions. When the program instructions stored in the memory are executed by the processor, the communication device executes a method as in any one of the above aspects or any possible design of any one of the aspects.

[0077] In a fifth aspect, a communication device is provided, comprising: a processor configured to execute a computer program or instructions to cause the communication device to perform the method described in any aspect or any possible design of the method described in any aspect. Optionally, the communication device further comprises a memory, which may be coupled to the processor or may exist independently of the processor, for example, the memory and the processor being two independent modules. The memory may be located externally or internally of the communication device.

[0078] In a sixth aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program or instruction, which, when executed, causes the method described in any one of the above aspects or any possible design of any one of the above aspects to be executed.

[0079] In a seventh aspect, a computer program product comprising instructions is provided, which, when executed, enables the method described in any one of the above aspects or any possible design of any one of the aspects to be executed.

[0080] The communication device provided in any of aspects 3 to 7 may be the network device described in aspect 1, or a component included in the network device, such as a chip or a chip system; alternatively, the communication device may be the first terminal device described in aspect 2, or a component included in the first terminal device, such as a chip or a chip system. When the device is a chip system, it may be composed solely of a chip or may include a chip and other discrete components.

[0081] It can be understood that when the communication device provided in any one of the third to seventh aspects is a chip, the sending action / function of the communication device can be understood as output information, and the receiving action / function of the communication device can be understood as input information.

[0082] In an eighth aspect, a communication device is provided for implementing the method described in any one of the above aspects or any possible design of any one of the above aspects. Optionally, the communication device includes a terminal device, a network device, a chip system, or a chip, wherein the terminal device can be referred to as a first terminal device.

[0083] Among them, the technical effects brought about by any design method in the third to eighth aspects can refer to the technical effects brought about by different design methods in the first aspect, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0084] FIG1 is a schematic diagram of the architecture of a communication system provided in an embodiment of the present application;

[0085] FIG2 is a schematic diagram of a control resource set configuration provided in an embodiment of the present application;

[0086] FIG3a is a schematic diagram of a PDCCH time-frequency resource distribution according to an embodiment of the present application;

[0087] FIG3b is a schematic diagram of time-frequency resource distribution of a control resource set provided in an embodiment of the present application;

[0088] FIG3c is a schematic diagram of time-frequency resource distribution of another control resource set provided in an embodiment of the present application;

[0089] FIG4 is a schematic diagram of the position distribution of a demodulation reference signal provided by an embodiment of the present application;

[0090] FIG5 is a flow chart of a communication method provided in an embodiment of the present application;

[0091] FIG6 is a schematic diagram of the position distribution of another demodulation reference signal provided in an embodiment of the present application;

[0092] FIG7 is a schematic diagram of the distribution of an orthogonal mask provided in an embodiment of the present application;

[0093] FIG8 is a schematic diagram of the distribution of another orthogonal mask provided in an embodiment of the present application;

[0094] FIG9 is a schematic diagram of the distribution of another orthogonal mask provided in an embodiment of the present application;

[0095] FIG10 is a schematic diagram of the distribution of another orthogonal mask provided in an embodiment of the present application;

[0096] FIG11 is a schematic diagram of the distribution of another orthogonal mask provided in an embodiment of the present application;

[0097] FIG12 is a schematic diagram of the distribution of another orthogonal mask provided in an embodiment of the present application;

[0098] FIG13 is a schematic diagram of the distribution of another orthogonal mask provided in an embodiment of the present application;

[0099] FIG14 is a schematic diagram of the distribution of another orthogonal mask provided in an embodiment of the present application;

[0100] FIG15 is a schematic diagram of the distribution of another orthogonal mask provided in an embodiment of the present application;

[0101] FIG16 is a schematic diagram of the distribution of another orthogonal mask provided in an embodiment of the present application;

[0102] FIG17 is a flow chart of another communication method provided in an embodiment of the present application;

[0103] FIG18 is a schematic diagram of information block distribution provided in an embodiment of the present application;

[0104] FIG19 is a flow chart of another communication method provided in an embodiment of the present application;

[0105] FIG20 is a schematic structural diagram of a communication device provided in an embodiment of the present application;

[0106] FIG21 is a schematic structural diagram of another communication device provided in an embodiment of the present application;

[0107] FIG22 is a schematic structural diagram of another communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0108] The technical solution in this application will be described below with reference to the accompanying drawings.

[0109] Throughout this application, the term "system" and "network" are interchangeable. This application presents various aspects, embodiments, or features centered around a system that may include multiple devices, components, modules, and the like. It should be understood that each system may include additional devices, components, modules, and the like, and / or may not include all of the devices, components, modules, and the like discussed in conjunction with the accompanying figures. Furthermore, combinations of these aspects may also be used.

[0110] Additionally, in the embodiments of this application, words such as "exemplarily" and "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described in this application as an "example" should not be construed as being preferred or advantageous over other embodiments or designs. Rather, the use of the word "example" is intended to present concepts in a concrete manner.

[0111] In the embodiments of the present application, “of”, “corresponding”, “relevant” and “corresponding” may sometimes be used interchangeably. It should be noted that when the distinction between them is not emphasized, the meanings they intend to express are consistent.

[0112] The network architecture and business scenarios described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. Ordinary technicians in this field will know that with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0113] FIG1 is a schematic diagram of the architecture of a communication system 1000 used in an embodiment of the present application. As shown in FIG1 , the communication system 1000 includes at least one network device (such as 110a and 110b in FIG1 ) and at least one terminal device (such as 120a-120j in FIG1 ). The terminal device can communicate with the network device wirelessly. Alternatively, different network devices can communicate with each other. Alternatively, different terminal devices can communicate with each other.

[0114] It should be pointed out that Figure 1 is only a schematic diagram. Although not shown, the communication system 1000 can also include other network devices. For example, the communication system 1000 can also include one or more core network (CN) devices, wireless relay devices and wireless backhaul devices, which are not specifically limited here.

[0115] The network device can be connected to the core network device via wireless or wired communication. The core network device and the network device can be independent and different physical devices, or the functions of the core network device and the logical functions of the network device can be integrated into the same physical device, or the functions of some core network devices and some network devices can be integrated into one physical device. This embodiment of the present application does not specifically limit this.

[0116] Optionally, the network device is a network-side device with wireless transceiver functions. The network device may be a device in a radio access network (RAN) that provides wireless communication functions for terminal devices, referred to as a RAN device. The RAN may be an access network in the 3rd Generation Partnership Project (3GPP), for example, 4G, 5G, or the future-oriented 6G network. The RAN may also be an open access network (open RAN, O-RAN or ORAN), a cloud radio access network (CRAN), or a communication network of two or more of the above networks. The RAN device may be a base station, an evolved NodeB (eNodeB), a transmission reception point (TRP), a next-generation base station (next generation nodeB, gNB) in a fifth-generation (5G) mobile communication system, a next-generation base station in a sixth-generation (6G) mobile communication system, a base station in a future mobile communication system, a wireless fidelity (WiFi) system, a long-range radio (LoRa) system, or an access node in a vehicle networking system. RAN equipment can also be a module or unit that performs some of the functions of a base station. For example, it can be a centralized unit (CU), a distributed unit (DU), or a radio unit (RU). The CU here performs the functions of the base station's radio resource control protocol and packet data convergence protocol (PDCP), and can also perform the functions of the service data adaptation protocol (SDAP); the DU performs the functions of the base station's radio link control layer and medium access control (MAC) layer, and can also perform some or all of the physical layer functions. For detailed descriptions of each of the above protocol layers, please refer to the relevant technical specifications of the 3rd Generation Partnership Project (3GPP). The CU and DU can be set up separately, or they can be included in the same network element, such as the baseband unit (BBU).The RU may be included in a radio frequency device or radio frequency unit, for example, a remote radio unit (RRU), an active antenna unit (AAU), or a remote radio head (RRH). In different systems, CU, DU, or RU may have different names, but those skilled in the art will understand their meanings. For example, in an ORAN system, CU may also be called O-CU (Open CU), DU may also be called O-DU, and RU may also be called O-RU. Any of the CU (or CU-CP, CU-UP), DU, and RU in this application may be implemented by a software module, a hardware module, or a combination of a software module and a hardware module. The radio access network device may be a macro base station (such as 110a in Figure 1), a micro base station or an indoor station (such as 110b in Figure 1), a relay node, a donor node, etc. The embodiments of this application do not limit the specific technology and specific device form adopted by the radio access network device. For ease of description, network device is referred to as the abbreviation of radio access network device, and base station is used as an example of radio access network device.

[0117] Optionally, the terminal device accesses the core network via a network device. The terminal device includes a device that provides voice and / or data connectivity to the user. Specifically, it includes a device that provides voice to the user, a device that provides data connectivity to the user, or a device that provides both voice and data connectivity to the user. For example, it may include a handheld device with wireless connectivity or a processing device connected to a wireless modem. The terminal device can communicate with the core network via the radio access network, exchange voice or data with the RAN, or exchange voice and data with the RAN. The terminal device may include user equipment (UE), wireless terminal device, mobile terminal device, D2D terminal device, V2X terminal device, machine-to-machine / machine-type communications (M2M / MTC) terminal device, Internet of Things (IoT) terminal device, subscriber unit, subscriber station, mobile station, remote station, access point (AP), remote terminal, access terminal, user terminal, user agent, or user device, etc. For example, it may include a mobile phone (or so-called "cellular" phone), a computer with a mobile terminal device, a portable, pocket-sized, handheld, or computer-built-in mobile device, etc. Examples include personal communication service (PCS) phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, and personal digital assistants (PDAs). Also included are limited devices, such as those with low power consumption, limited storage capacity, or limited computing power. Examples include information sensing devices such as barcode scanners, radio frequency identification (RFID), sensors, global positioning systems (GPS), and laser scanners.

[0118] The various terminal devices introduced above, if located on a vehicle (eg, placed in or installed in a vehicle), can be considered as vehicle-mounted terminal devices, which are also called on-board units (OBUs).

[0119] In the embodiment of the present application, the terminal device may further include a relay. Alternatively, it can be understood that anything that can communicate data with a base station can be considered a terminal device.

[0120] In the embodiments of the present application, the device for implementing the functions of the terminal device can be the terminal device, or it can be a device that can support the terminal device to implement the functions, such as a chip system, which can be installed in the terminal device. In the embodiments of the present application, the chip system can be composed of chips, or it can include chips and other discrete devices. In the technical solutions provided in the embodiments of the present application, the device for implementing the functions of the terminal is a terminal device as an example for description.

[0121] It should be understood that network devices and terminal devices can be fixed or mobile. Network devices and terminal devices can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; they can also be deployed on water; and they can also be deployed in the air on aircraft, balloons, and artificial satellites. The embodiments of this application do not limit the application scenarios of network devices and terminal devices.

[0122] The roles of network devices and terminal devices can be relative. For example, the helicopter or drone 120i in Figure 1 can be configured as a mobile base station. To terminal devices 120j that access the wireless access network through 120i, terminal device 120i is a network device; however, to network device 110a, 120i is a terminal device, meaning that communication between 110a and 120i occurs via a wireless air interface protocol. Of course, communication between 110a and 120i can also occur via a base station-to-base station interface protocol. In this case, relative to 110a, 120i is also a network device. Therefore, both network devices and terminal devices can be collectively referred to as communication devices. 110a and 110b in Figure 1 can be referred to as communication devices with network device functionality, and 120a-120j in Figure 1 can be referred to as communication devices with terminal device functionality.

[0123] Network devices and terminal devices, network devices and network devices, and terminal devices and terminal devices can communicate through authorized spectrum, unauthorized spectrum, or both. Communication can be carried out through spectrum below 6 gigahertz (GHz), spectrum above 6 GHz, or spectrum below 6 GHz and spectrum above 6 GHz simultaneously. The embodiments of the present application do not limit the spectrum resources used for wireless communications.

[0124] In the embodiments of the present application, the functions of the network device may also be performed by a module (such as a chip) in the network device, or by a control subsystem that includes the network device functions. The control subsystem that includes the network device functions here may be a control center in the above-mentioned application scenarios such as smart grid, industrial control, smart transportation, and smart city. The functions of the terminal device may also be performed by a module (such as a chip or a modem) in the terminal device, or by a device that includes the terminal device functions.

[0125] In an embodiment of the present application, a network device sends a downlink signal or downlink information to a terminal device, and the downlink information is carried on a downlink channel; the terminal device sends an uplink signal or uplink information to the network device, and the uplink information is carried on an uplink channel. In order to communicate with the network device, the terminal device needs to establish a wireless connection with the cell controlled by the network device. The cell with which the terminal device has established a wireless connection is called the serving cell of the terminal device. When the terminal device communicates with the serving cell, it will also be interfered with by signals from neighboring cells.

[0126] It should be noted that the solutions in the embodiments of the present application can also be applied to other communication systems, and the corresponding names can also be replaced by the names of corresponding functions in other communication systems.

[0127] To facilitate understanding of the embodiments of the present application, the following briefly describes the terms used in the embodiments of the present application. It should be understood that these descriptions are only for facilitating understanding of the embodiments of the present application and should not constitute any limitation on the present application.

[0128] 1. PDCCH

[0129] Similar to the long term evolution (LTE) communication system, the NR communication system defines PDCCH to transmit downlink control information (DCI).

[0130] For a terminal device, the terminal device may blindly detect candidate PDCCHs from a network device (such as a base station) in one or more search space sets (SS sets).

[0131] The SS set indicates the starting symbol and period of the PDCCH in the time domain. An SS set can be understood as the set of candidate PDCCHs that a terminal device needs to detect. The SS set is divided into a common search space set (CSS set) and a user search space set (USS set).

[0132] For PDCCH, unlike LTE communication system, NR communication system introduces the concept of control resource set (CORESET). Among them, CORESET can indicate the frequency band occupied by PDCCH in the frequency domain and the number of symbols occupied by PDCCH in the time domain. CORESET can be understood as the time-frequency resources used by the terminal device when using one or more SS sets to detect candidate PDCCH. For example, a CORESET consists of resource blocks (RBs), continuous in time domain A CORESET can appear at any time-frequency position in the bandwidth part (BWP) and is semi-statically configured by the network device through high-layer signaling. Each terminal device can be configured with one or more CORESETs, as shown in Figure 2.

[0133] The time-frequency resources used by a PDCCH are composed of one or more control channel elements (CCEs) in a CORESET, as shown in Figure 3a. The CCE is also called an aggregation level (AL).

[0134] Currently, the NR communication system supports PDCCH ALs 1, 2, 4, 8, and 16. A CCE consists of 6 resource element groups (REGs), each of which occupies one symbol in the time domain and one RB in the frequency domain. Among them, one RB includes 12 subcarriers in the frequency domain. In other words, each REG includes 12 resource elements (REs).

[0135] For a certain CORESET, there are two ways to map CCEs to REGs: interleaved mapping and non-interleaved mapping. Non-interleaved mapping is shown in Figure 3b, and interleaved mapping is shown in Figure 3c.

[0136] In the present application, a symbol may refer to an orthogonal frequency division multiplex (OFDM) symbol, which is the smallest time unit in the time domain in an OFDM system.

[0137] 2. PDCCH demodulation reference signal (DMRS)

[0138] Typically, when a terminal device processes a received PDCCH, it needs to perform channel estimation. To this end, the NR communication system introduces a PDCCH-specific DMRS, which can be described as PDCCH DMRS or PDCCH DMRS. The introduction of PDCCH DMRS enables network devices to transmit PDCCH using beamforming, thereby improving PDCCH coverage and performance.

[0139] For example, the DMRS for the PDCCH is transmitted using a pseudo-random sequence. For a candidate PDCCH, within a specific REG occupied by the candidate PDCCH, the DMRS for the PDCCH is mapped to some subcarriers in that REG, such as the fourth subcarrier out of every four subcarriers, as shown in Figure 4. Therefore, the overhead of the DMRS for the PDCCH is 1 / 4, meaning that three REs are used for DMRS transmission in each REG.

[0140] In this application, RE used to carry DMRS can be recorded as DMRS RE.

[0141] 3. PDCCH data information

[0142] The data information of the PDCCH can be understood as the DCI carried on the PDCCH, which can be recorded as: PDCCH Data.

[0143] It should be noted that, in the present application, a certain PDCCH includes two parts, namely, the data information of the PDCCH and the DMRS of the PDCCH.

[0144] 4. Antenna port

[0145] An antenna port is a logical port used for signal transmission. An antenna port can correspond to one or more physical antennas. Different antenna ports can correspond to the same physical antenna or different physical antennas. From the perspective of the receiver, each antenna port corresponds to an independent wireless channel. In the 3GPP NR standard, an antenna port is defined as an antenna port used to transmit a reference signal, which can be simply referred to as a reference signal antenna port. For example, an antenna port used to transmit DMRS can be simply referred to as a DMRS antenna port.

[0146] It should be noted that, in this application, antenna ports refer to DMRS antenna ports.

[0147] In addition, an antenna port is also referred to as a port for short. For example, a DMRS antenna port can also be referred to as a DMRS port for short.

[0148] 5. Antenna ports supported by PDCCH

[0149] Taking the NR communication system as an example, PDCCH only supports a single antenna port, and the port number is 2000. As a result, the DMRS of PDCCH also only supports one antenna port, that is, a single DMRS antenna port.

[0150] Generally, in a multiple-input multiple-output (MIMO) transmission scenario, since a PDCCH only supports a single antenna port, only single-stream transmission is supported for one PDCCH transmission.

[0151] In scenarios where multiple PDCCHs are transmitted for MU-MIMO, network equipment handles this transparently to the user equipment, using the same DMRS antenna port to transmit the PDCCHs of multiple users. In other words, the network equipment uses the same DMRS antenna port to transmit the PDCCHs of multiple users on the same time-frequency resources. In this case, orthogonality between the DMRSs of multiple PDCCHs may not be guaranteed, resulting in poor PDCCH demodulation performance. Furthermore, in cells with a large number of users, PDCCH capacity may be limited, impacting PDCCH performance.

[0152] In summary, in NR, PDCCH only supports a single antenna port. When multiple PDCCHs are transmitted using MU-MIMO, since the DMRSs of multiple PDCCHs are transmitted using the same antenna port, orthogonality between them may not be guaranteed, resulting in limited PDCCH demodulation performance and affecting PDCCH capacity.

[0153] In view of this, the present application provides a communication method, which can be applied to the system shown in Figure 1. The method includes: a network device determines L DMRS antenna ports from N DMRS antenna ports. The N DMRS antenna ports are used for PDCCH transmission, and any two of the N DMRS antenna ports are orthogonally multiplexed through at least one of the following: time division multiplexing (TDM), frequency division multiplexing (FDM), or code division multiplexing (CDM). N is a positive integer greater than or equal to 2, and L is a positive integer less than or equal to N. The network device sends the DMRS of the first PDCCH through the L DMRS antenna ports.

[0154] In this application, TDM between any two DMRS antenna ports means that different DMRS antenna ports are associated with or use different time domain resources. In this way, the PDCCH DMRS transmitted on different DMRS antenna ports can use different time domain resources, thereby ensuring that the DMRS of different PDCCHs are mutually orthogonal.

[0155] In this application, FDM between any two DMRS antenna ports means that different DMRS antenna ports are associated with or use different frequency domain resources. In this way, the PDCCH DMRS transmitted on different DMRS antenna ports can use different frequency domain resources, thereby ensuring that the DMRS of different PDCCHs are mutually orthogonal.

[0156] In this application, CDM between any two DMRS antenna ports means that different DMRS antenna ports are associated or use different orthogonal codes (as described below). In this way, PDCCH DMRS transmitted on different DMRS antenna ports can use different orthogonal codes, thereby ensuring that the DMRS of different PDCCHs are mutually orthogonal.

[0157] In this way, since N DMRS antenna ports can be used for PDCCH transmission and the N DMRS antenna ports are orthogonal to each other, when different PDCCH DMRSs are transmitted through different DMRS antenna ports among the N DMRS antenna ports, the DMRSs of different PDCCHs are orthogonal to each other. For example, the DMRS of the first PDCCH is orthogonal to the DMRSs of other PDCCHs, which helps to improve the PDCCH demodulation performance and PDCCH capacity.

[0158] Below, in conjunction with Figure 5, the communication method proposed in the embodiment of the present application is introduced in detail.

[0159] The communication method 500 proposed in this embodiment of the application includes the following operations:

[0160] S501: A network device determines L DMRS antenna ports from N DMRS antenna ports.

[0161] The network devices are introduced as follows:

[0162] This step can be performed by a network device. Unless otherwise specified, the "network device" in this application can refer to the network device itself, or a component in the network device (for example, a processor, chip, or chip system, etc.), or a logical module or software that can implement all or part of the network device functions.

[0163] Among them, L DMRS antenna ports are described as follows:

[0164] L is a positive integer less than or equal to N, that is, the L DMRS antenna ports are one or more DMRS antenna ports among the N DMRS antenna ports.

[0165] Among them, the introduction of N DMRS antenna ports is as follows:

[0166] N is a positive integer greater than or equal to 2, that is, the N DMRS antenna ports are two or more DMRS antenna ports.

[0167] First, N DMRS antenna ports are used for PDCCH transmission and can be recorded as PDCCH DMRS antenna ports. In other words, PDCCH supports multiple antenna ports.

[0168] Second, orthogonal multiplexing is performed between any two of the N DMRS antenna ports using at least one of the following: TDM, FDM, or CDM.

[0169] For example, any two DMRS antenna ports among the N DMRS antenna ports are orthogonally multiplexed using CDM. For another example, any two DMRS antenna ports among the N DMRS antenna ports are orthogonally multiplexed using CDM and FDM.

[0170] Next, two implementation modes (the first implementation mode and the second implementation mode) are introduced:

[0171] In a first implementation, FDM is performed between the data information of the PDCCH and the DMRS of the PDCCH.

[0172] First, the DMRS overhead of PDCCH is introduced:

[0173] In a first embodiment, the transmission resources of the first PDCCH include multiple REGs, each of the multiple REGs includes M first REs, and the M first REGs are used to carry the DMRS of the PDCCH, where M is a positive integer greater than 3. Each of the multiple REGs includes one OFDM symbol in the time domain and one RB in the frequency domain. For details, please refer to the introduction in the glossary section and will not be repeated here.

[0174] It should be understood that in the present application, each REG includes multiple REs (e.g., 12 REs), among which the RE used to carry the PDCCH DMRS is described as the first RE. For each REG, in addition to the M first REs, other REs may also be included, such as REs carrying PDCCH data information.

[0175] Since this application considers that DMRS antenna ports use orthogonal cover codes (OCCs) in the frequency domain, and the length of OCCs is generally an even number, in this application, the number of REs used to carry DMRS in a REG is an even number. Furthermore, considering both DMRS overhead and DMRS performance, a DMRS overhead of 1 / 3 is preferred, i.e., M = 4. In other words, the first four REs in each REG are used to carry the DMRS for the PDCCH.

[0176] For example, Figure 6 shows the distribution of PDCCH data and DMRS on a REG. The blank squares represent REs carrying data information, while the squares filled with diagonal lines represent REs carrying DMRS.

[0177] It should be understood that M may also be other values, such as M=6, which is not limited in this application.

[0178] It should be noted that the meaning of OCC is as follows:

[0179] The DMRS for the PDCCH is transmitted using a pseudo-random sequence. An orthogonal sequence can be superimposed on this pseudo-random sequence to support multiple orthogonal DMRS antenna ports. The pseudo-random sequence is referred to as a base sequence, and the orthogonal sequence is referred to as an OCC. The OCC may also have other descriptions, such as an OCC sequence, which is not limited in this application.

[0180] OCC includes time-domain OCC and frequency-domain OCC. Time-domain OCC can be understood as using OCC in the time domain, which can be denoted as TD-OCC (time domain-OCC). Frequency-domain OCC can be understood as using OCC in the frequency domain, which can be denoted as FD-OCC (frequency domain-OCC).

[0181] It should be noted that the length of OCC is as follows:

[0182] For an OCC with a length of 2, it can be understood that the OCC has two elements. For example, the OCC with a length of 2 can be a sequence including the sequence in Table 1:

[0183] Table 1

[0184] For an OCC with a length of 4, it can be understood that the OCC has four elements. For example, the OCC with a length of 4 can be a sequence including the sequence in Table 2:

[0185] Table 2

[0186] In this application, a time-domain OCC with a length of 2 can be expressed as a 2-length TD-OCC. A time-domain OCC with a length of 4 can be expressed as a 4-length TD-OCC. A frequency-domain OCC with a length of 2 can be expressed as a 2-length FD-OCC. A frequency-domain OCC with a length of 4 can be expressed as a 4-length FD-OCC.

[0187] In the first embodiment, as a first option (Option 1), any two of the N DMRS antenna ports are orthogonally multiplexed using CDM. For example, any two of the N DMRS antenna ports are associated with (or use) different frequency-domain OCCs and / or different time-domain OCCs. In other words, the N DMRS antenna ports are associated with (or use) the same time-frequency resources, but orthogonality is maintained by associating (or using) different time-domain OCCs and / or different frequency-domain OCCs.

[0188] For example, any two of the N DMRS antenna ports are associated with (or use) different frequency domain OCCs. Depending on the length of the associated (or used) frequency domain OCCs, the following examples (i.e., Examples 1-2 below) may be used:

[0189] Example 1, frequency domain OCC with correlation length 2:

[0190] Since there are 4 first REs in a certain REG for carrying DMRS (i.e., 4 DMRS REs), for the same DMRS antenna port, the first two DMRS REs and the last two DMRS REs are associated with the same OCC of length 2. In this case, a total of 2 DMRS antenna ports are supported, i.e., N=2.

[0191] As shown in Figure 7, each small square in Figure 7 represents an RE. The N DMRS antenna ports are respectively denoted as DMRS antenna port 0 and DMRS antenna port 1. In Figure 7, DMRS antenna port 0 and DMRS antenna port 1 are associated with different frequency domain OCCs to maintain orthogonality.

[0192] In Figure 7 , the box where the letter a is located shows the frequency domain OCC associated with DMRS antenna port 0. The frequency domain OCC associated with DMRS antenna port 0 is [+1, +1].

[0193] In Figure 7 , the box where the letter b is located shows the frequency domain OCC associated with DMRS antenna port 1. The frequency domain OCC associated with DMRS antenna port 1 is [+1, -1].

[0194] It should be noted that in Figure 7, the box containing the letter a and the box containing the letter b actually correspond to the same time-frequency resource. For ease of description, how different DMRS antenna ports are code-division multiplexed in the same time-frequency resource is shown.

[0195] Example 2, frequency domain OCC with a correlation length of 4:

[0196] Since there are 4 first REs in a certain REG for carrying DMRS (ie, 4 DMRS REs), for the same DMRS antenna port, the 4 DMRS REs are associated with exactly one OCC of length 4, as shown in Figure 8. In this case, a total of 4 DMRS antenna ports are supported, N=4.

[0197] Specifically, the four DMRS antenna ports are respectively recorded as: DMRS antenna port 0 to DMRS antenna port 3. The four DMRS antenna ports are associated with different frequency domain OCCs to maintain orthogonality.

[0198] For example, the frequency domain OCC associated with DMRS antenna port 0 is [+1, +1, +1, +1]. The frequency domain OCC associated with DMRS antenna port 1 is [+1, -1, +1, -1]. The frequency domain OCC associated with DMRS antenna port 2 is [+1, +1, -1, -1]. The frequency domain OCC associated with DMRS antenna port 3 is [+1, -1, -1, +1].

[0199] It should be understood that for the above example 1, when the time domain symbol of the PDCCH is an even number (such as 2 or 4), the above frequency domain OCC can also be replaced by: time domain OCC. For the above example 2, when the time domain symbol of the PDCCH is an even number (such as 4), the above frequency domain OCC can also be replaced by: time domain OCC.

[0200] For another example, any two DMRS antenna ports among the N DMRS antenna ports are orthogonally multiplexed using different frequency domain OCCs and time domain OCCs. Depending on the length of the associated (or used) frequency domain OCC, the following implementations (i.e., Examples 3-6 below) may be implemented:

[0201] Example 3, correlation length 2 for frequency domain OCC and length 2 for time domain OCC:

[0202] Each of the N DMRS antenna ports is associated with a time-domain OCC of length 2 and a frequency-domain OCC of length 2 for weighted processing. In this case, a total of four DMRS antenna ports are supported, i.e., N = 4. For example, when the PDCCH time-domain symbol is 2, the time-domain OCCs and frequency-domain OCCs associated with different DMRS antenna ports are shown in Figure 9. For another example, when the PDCCH time-domain symbol is 4, the time-domain OCCs and frequency-domain OCCs associated with different DMRS antenna ports are shown in Figure 10.

[0203] Specifically, the four DMRS antenna ports are respectively recorded as DMRS antenna port 0 to DMRS antenna port 3. The frequency domain OCC with a length of 2 and the time domain OCC with a length of 2 associated with the four DMRS antenna ports remain orthogonal.

[0204] For example, the time domain OCC associated with DMRS antenna port 0 is [+1, +1], and the frequency domain OCC associated with DMRS antenna port 0 is [+1, +1]. The time domain OCC associated with DMRS antenna port 1 is [+1, -1], and the frequency domain OCC associated with DMRS antenna port 0 is [+1, +1]. The time domain OCC associated with DMRS antenna port 2 is [+1, +1], and the frequency domain OCC associated with DMRS antenna port 2 is [+1, -1]. The time domain OCC associated with DMRS antenna port 3 is [+1, -1], and the frequency domain OCC associated with DMRS antenna port 3 is [+1, -1].

[0205] Example 4, correlation length 4 for frequency domain OCC and length 2 for time domain OCC:

[0206] Each of the N DMRS antenna ports is associated with a time-domain OCC of length 2 and a frequency-domain OCC of length 4, and weighted processing is performed. In this case, a total of 8 DMRS antenna ports are supported, that is, N = 8. For example, when the time-domain symbol of the PDCCH is 2, the time-domain OCCs and frequency-domain OCCs associated with different DMRS antenna ports are shown in Figure 11. For another example, when the time-domain symbol of the PDCCH is 4, the time-domain OCCs and frequency-domain OCCs associated with different DMRS antenna ports are shown in Figure 12.

[0207] Specifically, the eight DMRS antenna ports are respectively recorded as DMRS antenna port 0 to DMRS antenna port 7. The eight DMRS antenna ports are associated with a frequency domain OCC with a length of 4 and a time domain OCC with a length of 2 to maintain orthogonality.

[0208] For example, the time domain OCC associated with DMRS antenna port 0 is [+1, +1], and the frequency domain OCC associated with DMRS antenna port 0 is [+1, +1, +1, +1]. The time domain OCC associated with DMRS antenna port 1 is [+1, -1], and the frequency domain OCC associated with DMRS antenna port 1 is [+1, +1, +1, +1]. The time domain OCC associated with DMRS antenna port 2 is [+1, +1], and the frequency domain OCC associated with DMRS antenna port 2 is [+1, -1, +1, -1]. The time domain OCC associated with DMRS antenna port 3 is [+1, -1], and the frequency domain OCC associated with DMRS antenna port 3 is [+1, -1, +1, -1]. The time domain OCC associated with DMRS antenna port 4 is [+1, +1], and the frequency domain OCC associated with DMRS antenna port 4 is [+1, +1, -1, -1]. The time domain OCC associated with DMRS antenna port 5 is [+1, -1], and the frequency domain OCC associated with DMRS antenna port 5 is [+1, +1, -1, -1]. The time domain OCC associated with DMRS antenna port 6 is [+1, +1], and the frequency domain OCC associated with DMRS antenna port 6 is [+1, -1, -1, +1]. The time domain OCC associated with DMRS antenna port 7 is [+1, -1], and the frequency domain OCC associated with DMRS antenna port 7 is [+1, -1, -1, +1].

[0209] Example 5, frequency domain OCC with correlation length 2 and time domain OCC with correlation length 4:

[0210] Each of the N DMRS antenna ports is associated with a frequency-domain OCC of length 2 and a time-domain OCC of length 4 for weighted processing. In this case, a total of 8 DMRS antenna ports are supported, i.e., N = 8. For example, when the time-domain symbol of the PDCCH is 4, the frequency-domain OCCs and time-domain OCCs associated with different DMRS antenna ports are shown in Figure 13.

[0211] Specifically, the eight DMRS antenna ports are respectively recorded as DMRS antenna port 0 to DMRS antenna port 7. The eight DMRS antenna ports are associated with a time domain OCC with a length of 4 and a frequency domain OCC with a length of 2 to maintain orthogonality.

[0212] For example, the frequency domain OCC associated with DMRS antenna port 0 is [+1, +1], and the time domain OCC associated with DMRS antenna port 0 is [+1, +1, +1, +1]. The frequency domain OCC associated with DMRS antenna port 1 is [+1, -1], and the time domain OCC associated with DMRS antenna port 1 is [+1, +1, +1, +1]. The frequency domain OCC associated with DMRS antenna port 2 is [+1, +1], and the time domain OCC associated with DMRS antenna port 2 is [+1, -1, +1, -1]. The frequency domain OCC associated with DMRS antenna port 3 is [+1, -1], and the time domain OCC associated with DMRS antenna port 3 is [+1, -1, +1, -1]. The frequency domain OCC associated with DMRS antenna port 4 is [+1, +1], and the time domain OCC associated with DMRS antenna port 4 is [+1, +1, -1, -1]. The frequency domain OCC associated with DMRS antenna port 5 is [+1, -1], and the time domain OCC associated with DMRS antenna port 5 is [+1, +1, -1, -1]. The frequency domain OCC associated with DMRS antenna port 6 is [+1, +1], and the time domain OCC associated with DMRS antenna port 6 is [+1, -1, -1, +1]. The frequency domain OCC associated with DMRS antenna port 7 is [+1, -1], and the time domain OCC associated with DMRS antenna port 7 is [+1, -1, -1, +1].

[0213] Example 6, correlation length 4 frequency domain OCC, and length 4 time domain OCC:

[0214] Each of the N DMRS antenna ports is associated with a frequency-domain OCC of length 4 and a time-domain OCC of length 4 for weighted processing. In this case, a total of 16 DMRS antenna ports are supported, i.e., N = 16. For example, when the time-domain symbol of the PDCCH is 4, the frequency-domain OCCs and time-domain OCCs associated with different DMRS antenna ports are shown in Figure 14.

[0215] Specifically, the 16 DMRS antenna ports are respectively recorded as DMRS antenna port 0 to DMRS antenna port 15. The time domain OCC with a length of 4 and the frequency domain OCC with a length of 4 associated with the 16 DMRS antenna ports remain orthogonal.

[0216] In the first embodiment, as a second option (option 2), any two of the N DMRS antenna ports are orthogonally multiplexed using CDM and / or FDM. For example, the N DMRS antenna ports belong to at least two CDM groups, and each of the at least two CDM groups includes a portion of the N DMRS antenna ports. Any two DMRS antenna ports in any one of the at least two CDM groups are associated with different frequency domain OCCs and / or different time domain OCCs. The DMRS antenna ports included in any two CDM groups in the at least two CDM groups are associated with different frequency domain resources.

[0217] It should be noted that in this application, DMRS antenna ports that occupy the same time-frequency resources and whose associated time-domain OCCs and / or frequency-domain OCCs maintain orthogonality belong to one CDM group, while DMRS antenna ports that occupy different time-frequency resources belong to different CDM groups. The number of DMRS antenna ports included in different CDM groups can be the same or different. The following description uses the example of different CDM groups including the same number of DMRS antenna ports, which should not be construed as limiting this application.

[0218] In the present application, the four DMRS REs in each REG may be divided into two CDM groups (CDM groups), each CDM group including two DMRS REs, as shown in the boxes 'a1' and 'b1' in FIG15 .

[0219] Preferably, taking two CDM groups as an example, consider maintaining orthogonality between different DMRS antenna ports in the same CDM group by associating different frequency-domain OCCs. Specifically, each CDM group can be associated with a frequency-domain OCC of length 2, as shown in the boxes 'a2' and 'b2' in Figure 15. In this case, each CDM group contains two DMRS antenna ports, and the two CDM groups support a total of four DMRS antenna ports. That is, N = 4.

[0220] Preferably, taking two CDM groups as an example, consider maintaining orthogonality between different DMRS antenna ports in the same CDM group by associating different time-domain OCCs. Specifically, when the PDCCH time-domain symbol is 2, each CDM group can be associated with a time-domain OCC of length 2, as shown in the boxes 'a3' and 'b3' in Figure 15. In this case, each CDM group contains two DMRS antenna ports, and the two CDM groups support a total of four DMRS antenna ports. That is, N = 4.

[0221] Preferably, taking two CDM groups as an example, consider maintaining orthogonality between different DMRS antenna ports in the same CDM group by associating different time-domain OCCs and frequency-domain OCCs. Specifically, when the number of time-domain symbols of the PDCCH is 2, each CDM group can be associated with a time-domain OCC of length 2 and a frequency-domain OCC of length 2, as shown in the boxes 'a4' and 'b4' in Figure 15. In this case, a total of 8 DMRS antenna ports are supported, that is, N = 8.

[0222] It is easy to understand that, within each CDM group, the time domain OCC and frequency domain OCC associated with different DMRS antenna ports can be found in the introduction of the 'first option of the first implementation method' and will not be described in detail.

[0223] In a second embodiment, time-division multiplexing (TDM) is performed between the PDCCH data information and the PDCCH DMRS. For example, the PDCCH time domain resource includes K symbols, where the K symbols include a first symbol and a second symbol. The PDCCH data information occupies the first symbol, and the PDCCH DMRS occupies the second symbol. K is a positive integer greater than or equal to 2.

[0224] Taking Figure 16 as an example, K = 2, the PDCCH data information occupies the first symbol, as shown by the empty squares. The PDCCH DMRS occupies the second symbol, as shown by the filled squares. Of course, the PDCCH DMRS can also occupy more symbols, such as 2 symbols, 4 symbols, etc., which is not limited in this application.

[0225] In the second embodiment, as the first option (Option 1), any two of the N DMRS antenna ports are orthogonally multiplexed using CDM. For example, any two of the N DMRS antenna ports are associated with or use different frequency-domain OCCs and / or different time-domain OCCs. In other words, the N DMRS antenna ports occupy the same time-frequency resources and maintain orthogonality by being associated with different time-domain OCCs and / or different frequency-domain OCCs.

[0226] For example, any two of the N DMRS antenna ports are associated with or use different frequency domain OCCs. Depending on the length of the associated frequency domain OCCs, the following examples may be used:

[0227] Each DMRS antenna port can be associated with a frequency domain OCC of length 2, as shown in the box 'a1' in Figure 16. In this case, a total of 2 DMRS antenna ports are supported, that is, N=2.

[0228] Each DMRS antenna port can be associated with a frequency domain OCC of length 4, as shown in the box 'a2' in Figure 16. In this case, a total of 4 DMRS antenna ports are supported, that is, N=4.

[0229] For another example, any two of the N DMRS antenna ports are associated with or use different time domain OCCs. Depending on the length of the associated time domain OCCs, the following examples may be used:

[0230] When the DMRS time domain symbol of the PDCCH is an even number (such as 2 or 4), each DMRS antenna port can be associated with a time domain OCC of length 2. In this case, a total of 2 DMRS antenna ports are supported, that is, N=2.

[0231] When the number of DMRS time-domain symbols of the PDCCH is an even number (eg, 4), each DMRS antenna port can be associated with a time-domain OCC of length 4. In this case, a total of 4 DMRS antenna ports are supported, ie, N=4.

[0232] In a second embodiment, as a second option (option 2), any two of the N DMRS antenna ports are orthogonally multiplexed using CDM and / or FDM. For example, the N DMRS antenna ports belong to at least two CDM groups, and each of the at least two CDM groups includes a portion of the N DMRS antenna ports. Any two DMRS antenna ports in any one of the at least two CDM groups are associated with or use different frequency domain OCCs and / or different time domain OCCs. The DMRS antenna ports included in any two CDM groups in the at least two CDM groups are associated with different frequency domain resources.

[0233] Taking three CDM groups as an example, the DMRS antenna ports in each CDM group can each include four REs. Consider maintaining orthogonality between different DMRS antenna ports in the same CDM group by associating different frequency-domain OCCs. Each CDM group can be associated with a frequency-domain OCC of length 2, as shown in the box 'b1' in Figure 16. In this case, a total of six DMRS antenna ports are supported, i.e., N = 6.

[0234] Taking three CDM groups as an example, the DMRS antenna ports in each CDM group can each include four REs. Consider maintaining orthogonality between different DMRS antenna ports in the same CDM group by associating different frequency-domain OCCs. Each CDM group can be associated with a frequency-domain OCC of length 4, as shown in the box 'b2' in Figure 16. In this case, a total of 12 DMRS antenna ports are supported, i.e., N = 12.

[0235] Taking two CDM groups as an example, the DMRS antenna ports in each CDM group can each include six REs. Consider maintaining orthogonality between different DMRS antenna ports in the same CDM group by associating different frequency-domain OCCs. Each CDM group can be associated with a frequency-domain OCC of length 2, as shown in the box 'c2' in Figure 16. In this case, a total of four DMRS antenna ports are supported, i.e., N = 4.

[0236] Taking two CDM groups as an example, when the PDCCH's DMRS time-domain symbols are even (e.g., 2 or 4), each DMRS antenna port can be associated with a time-domain OCC of length 2 and a frequency-domain OCC of length 2. In this case, a total of eight DMRS antenna ports are supported, i.e., N = 8.

[0237] In the second embodiment, as a third option (option 3): any two of the N DMRS antenna ports are orthogonally multiplexed using FDM. For example, any two of the N DMRS antenna ports are associated with or use different frequency domain resources. For example, N=3, DMRS antenna port 0 occupies 4 REs, such as the 1st / 2nd / 7th / 8th RE of each REG. DMRS antenna port 1 occupies 4 REs, such as the 3rd / 4th / 9th / 10th RE of each REG. DMRS antenna port 2 occupies 4 REs, such as the 5th / 6th / 11th / 12th RE of each REG.

[0238] It should be understood that the above two implementations (i.e., the first implementation and the second implementation) are for the purpose of exemplifying N DMRS antenna ports and should not be understood as limiting the present application. Of course, there may be more combinations, and in different combinations, N may have other values, for example, N may have values ​​of 2. T Or 3*Q, where T and Q are positive integers.

[0239] For the network device, after determining L DMRS antenna ports, the network device executes S502:

[0240] S502: The network device sends a first PDCCH to the first terminal device via L DMRS antenna ports. Correspondingly, the first terminal device receives the first PDCCH from the network device via the L DMRS antenna ports.

[0241] The first terminal device is introduced as follows:

[0242] This step can be performed by the first terminal device. Unless otherwise specified, the "first terminal device" in this application can refer to the first terminal device itself, or a component in the first terminal device (for example, a processor, chip, or chip system, etc.), or it can also be a logical module or software that can realize all or part of the functions of the first terminal device.

[0243] The L DMRS antenna ports can be found in the introduction of S501 and will not be described in detail.

[0244] Among them, the introduction of the first PDCCH is as follows:

[0245] The first PDCCH includes two parts, ie, data information of the first PDCCH and a DMRS of the first PDCCH.

[0246] It should be understood that, for the DMRS of the first PDCCH, the network device sends the DMRS of the first PDCCH to the first terminal device through L DMRS antenna ports, including: the network device sends the DMRS of the first PDCCH to the first terminal device through at least one of the time domain resources, frequency domain resources, or OCC associated with the L DMRS antenna ports, and the L DMRS antenna ports.

[0247] For the data information of the first PDCCH, the network device sends the data information of the first PDCCH to the first terminal device through L DMRS antenna ports, which only means that the network device sends the data information of the first PDCCH to the first terminal device through the L antenna ports of the DMRS that sends the first PDCCH, and does not use any one of the time domain resources, frequency domain resources and OCC associated with the L DMRS antenna ports to send the data information of the first PDCCH to the first terminal device.

[0248] It should be understood that when the network device executes S502, the PDCCH involved in the above two implementations (ie, the first implementation and the second implementation) can be replaced by: the first PDCCH.

[0249] It is easy to understand that, for the first terminal device, as shown in FIG17 , before executing S502, the first terminal device also executes S503:

[0250] S503. The first terminal device determines L DMRS antenna ports.

[0251] The L DMRS antenna ports can be found in the introduction of S501 and will not be described in detail.

[0252] Here, S503 is introduced in combination with two implementation plans (the first implementation plan and the second implementation plan below):

[0253] First embodiment: The communication method of this application includes the following steps:

[0254] S503a: The network device sends first information to the first terminal device. Correspondingly, the first terminal device receives the first information from the network device.

[0255] The first information is as follows:

[0256] The first information indicates the L DMRS antenna ports, such as the first information includes the port numbers of the L DMRS antenna ports.

[0257] In one possible implementation, the first information indicates the DMRS antenna port at the terminal device granularity, that is, the first information instructs the first terminal device to use L DMRS antenna ports on the first SS set to detect the first PDCCH. The first SS set is all SS sets associated with all CORESETs of the first terminal device.

[0258] It can be understood that all PDCCH transmissions of the first terminal device use the above L DMRS antenna ports. In other words, the first terminal device uses the above L DMRS antenna ports to monitor PDCCH on any SS set associated with any CORESET configured by itself.

[0259] In one possible implementation, the first information indicates the DMRS antenna port at a BWP granularity, i.e., the first information instructs the first terminal device to use L DMRS antenna ports on a second SS set to detect the first PDCCH. The second SS set is all SS sets associated with all CORESETs on the first BWP, and the first BWP is one of all BWPs of the first terminal device.

[0260] It can be understood that: all PDCCH transmissions of the first terminal device on the same BWP (such as the first BWP mentioned above) use the above-mentioned L DMRS antenna ports, and the DMRS antenna ports used for PDCCH transmissions on different BWPs are independently configured and can be the same or different. In other words, the first terminal device uses the above-mentioned L DMRS antenna ports to monitor PDCCH on all SS set(s) associated with all CORESET(s) associated with the first BWP.

[0261] In one possible implementation, the first information indicates the DMRS antenna port at a CORESET granularity, that is, the first information instructs the first terminal device to use L DMRS antenna ports on a third SS set to detect the first PDCCH. The third SS set is all SS sets associated with the first CORESET, and the first CORESET is one CORESET among all CORESETs of the first terminal device.

[0262] It can be understood that all PDCCH transmissions performed by the first terminal device using the same CORESET use the above-mentioned L DMRS antenna ports, and the DMRS antenna ports used for PDCCH transmissions performed on different CORESETs are independently configured and can be the same or different. In other words, the first terminal device uses the above-mentioned L DMRS antenna ports to monitor PDCCH on all SS set(s) associated with the first CORESET.

[0263] In one possible implementation, the first information indicates the DMRS antenna port at a CORESET group granularity, that is, the first information instructs the first terminal device to use L DMRS antenna ports on a fourth SS set to detect the first PDCCH. The fourth SS set is all SS sets associated with the first CORESET group, the first CORESET group is one CORESET group among all CORESET groups of the first terminal device, and each CORESET group includes one or more CORESETs.

[0264] It can be understood that all PDCCH transmissions performed by the first terminal device using the same CORESET group use the above-mentioned L DMRS antenna ports, and the DMRS antenna ports used for PDCCH transmissions performed on different CORESET groups are independently configured and can be the same or different. In other words, the first terminal device uses the above-mentioned L DMRS antenna ports to monitor PDCCH on all SS set(s) associated with the first CORESET group.

[0265] In one possible implementation, the first information indicates the DMRS antenna port at an SS set granularity, that is, the first information instructs the first terminal device to use L DMRS antenna ports on a fifth SS set to detect the first PDCCH, wherein the fifth SS set is one of all SS sets of the first terminal device.

[0266] It can be understood that all PDCCH transmissions performed by the first terminal device using the same SS set (such as the fifth SS set mentioned above) adopt the above-mentioned L DMRS antenna ports. The DMRS ports used for PDCCH transmissions performed by the first terminal device on different SS sets are independently configured and can be the same or different. In other words, the first terminal device uses the above-mentioned L DMRS antenna ports to monitor PDCCH on the fifth SS set.

[0267] In one possible implementation, the first information indicates the DMRS antenna port at the granularity of the SS set group, that is, the first information indicates that the first terminal device uses L DMRS antenna ports on the first SS set group to detect the first PDCCH. The first SS set group is one of all SS set groups of the first terminal device. Each SS set group includes one or more SS sets.

[0268] It can be understood that: all PDCCH transmissions performed by the first terminal device using the same SS set group (such as the first SS set group mentioned above) adopt the above-mentioned L DMRS antenna ports. The DMRS ports used for PDCCH transmissions performed by the first terminal device on different SS set groups are independently configured and can be the same or different. In other words, the first terminal device uses the above-mentioned L DMRS antenna ports to monitor PDCCH on the first SS set group.

[0269] The first information may be carried in at least one of the following:

[0270] Radio resource control (RRC) signaling, system information block (SIB), multimedia access control element (MAC CE), or downlink control information (DCI), etc.

[0271] A possible implementation method corresponds to the case where the first information is carried in a DCI, and the DCI corresponds to a first terminal device group. The first terminal device group includes at least one terminal device. The first information is carried in the first information block of the DCI, wherein the first information block corresponds to one or more terminal devices in the first terminal device group, and the one or more terminal devices include the first terminal device. Taking Figure 18 as an example, the DCI carrying the first information can be a terminal device group common DCI, such as a UE group common DCI, which is dedicated to indicating the L DMRS antenna ports used by each terminal device in a terminal device group (such as the above-mentioned first terminal device group). Exemplarily, the DCI carrying the first information includes X information blocks, the number of bits occupied by each information block is greater than or equal to 1, and each information block corresponds to one or more terminal devices, thereby indicating the PDCCH DMRS antenna port of the corresponding terminal device. X is a positive integer greater than or equal to 1.

[0272] Taking Figure 18 as an example, the first information is carried in the first information block, thereby indicating the L DMRS antenna ports for the first terminal device. For example, when the first PDCCH transmits the second DCI, the first information block of the first DCI indicates the DMRS antenna port used to monitor the first PDCCH.

[0273] Second embodiment: The communication method of this application includes the following steps:

[0274] S503b. The first terminal device determines L DMRS antenna ports according to the second information.

[0275] The second information is introduced in combination with the following three possible implementations:

[0276] In one possible implementation, the second information includes a radio network tempory identity (RNTI) of the first terminal device, such as a cell radio network tempory identity (C-RNTI). That is, the L DMRS antenna ports are determined based on the RNTI of the first terminal device.

[0277] For example, when L=1, the numbering of the L DMRS antenna ports satisfies: n RNTI mod N, where n RNTI Represents the RNTI value of the first terminal device, where mod is a modulo operation.

[0278] For example, when L>1, the number of a DMRS antenna port in the L DMRS antenna ports satisfies: n RNTImod N, where n RNTI represents the RNTI value of the first terminal device, and mod is a modulo operation. For example, the above formula (ie, n RNTI mod N) defines the number of the first DMRS antenna port in the L DMRS antenna ports, and the numbers of the remaining L-1 DMRS antenna ports increase in sequence. For example, the number of the Mth DMRS antenna port in the L DMRS antenna ports satisfies: (n RNTI mod N+M-1)mod N.

[0279] In a possible implementation manner, the second information includes the RNTI of the first terminal device and the number of the first time unit. That is, the L DMRS antenna ports are determined according to the RNTI of the first terminal device and the number of the first time unit.

[0280] For example, when L=1, the numbering of the L DMRS antenna ports satisfies: Y -1 =n RNTI , where n RNTI Indicates the RNTI value of the first terminal device, represents the number of the first time unit, A and D are positive integers, mod is a modulo operation. For example, A can take any value from {39827, 39829, 39839}, and D=65537.

[0281] For another example, when L>1, the number of a DMRS antenna port among the L DMRS antenna ports satisfies: Y -1 =n RNTI , where n RNTI Indicates the RNTI value of the first terminal device, represents the number of the first time unit, A and D are positive integers, and mod is a modulo operation. For example, the above formula defines the number of the first DMRS antenna port among the L DMRS antenna ports, and the numbers of the remaining L-1 DMRS antenna ports increase in sequence, such that the number of the Mth DMRS antenna port among the L DMRS antenna ports satisfies:

[0282] The first time unit can be understood as the time unit in which the first terminal device detects the first PDCCH. For example, the first terminal device receives the first PDCCH via the L DMRS antenna ports during the first time unit. In other words, the L DMRS antenna ports are the DMRS antenna ports used by the first terminal device during the first time unit.

[0283] In this way, since the first terminal device uses different time unit numbers at different times, the DMRS antenna ports determined by the first terminal device at different times are also different, thereby reducing the probability of 'DMRS antenna port conflict'.

[0284] In one possible implementation, the second information includes the RNTI of the first terminal device, the number of the first time unit, and the number of the first CORESET. That is, the L DMRS antenna ports are determined based on the RNTI of the first terminal device, the number of the first time unit, and the number of the first CORESET.

[0285] For example, when L=1, the numbering of the L DMRS antenna ports satisfies: Y p,-1 =n RNTI , where n RNTI Indicates the RNTI value of the first terminal device, represents the number of the first time unit, p represents the number of the first CORESET, D is a positive integer, and mod is a modulo operation. D=65537.

[0286] Among them, A p is a positive integer determined by p. For example, all CORESETs of the first terminal device are divided into 3 groups, and the DMRS antenna ports used for PDCCH transmission in each CORESET group are the same. In this case, A p =39827for pmod3=0;A p =39829for pmod3=1;A p =39839for pmod3=2.

[0287] Among them, A p =39827for pmod3=0, which can be understood as: in the case of pmod3=0, A p =39827.

[0288] Among them, A p =39829for pmod3=1, which can be understood as: in the case of pmod3=1, A p =39829.

[0289] Among them, A p =39839for pmod3=2, which can be understood as: in the case of pmod3=2, A p =39839.

[0290] For another example, when L>1, the number of a DMRS antenna port among the L DMRS antenna ports satisfies: Y p,-1 =n RNTI , where n RNTI Indicates the RNTI value of the first terminal device, represents the number of the first time unit, p represents the number of the first CORESET, D is a positive integer, and mod is a modulo operation. D = 65537. For example, the above formula defines the number of the first DMRS antenna port among the L DMRS antenna ports, and the numbers of the remaining L-1 DMRS antenna ports increase in sequence, such that the number of the Mth DMRS antenna port among the L DMRS antenna ports satisfies:

[0291] Among them, the first time unit can be referred to the introduction of Example 2 and will not be repeated here.

[0292] The first CORESET can be understood as the CORESET used by the first terminal device to detect the first PDCCH. For example, the first terminal device receives the first PDCCH on the first CORESET via the L DMRS antenna ports. In other words, the L DMRS antenna ports are the DMRS antenna ports used by the first terminal device on the first CORESET.

[0293] In this way, since the time unit numbers used by the first terminal device at different times are different, the DMRS antenna ports determined by the first terminal device at different times are also different, and / or, since the numbers of different CORESETs are different, the DMRS antenna ports determined by the first terminal device when detecting PDCCH at different CORESETs may also be different, thereby further reducing the probability of 'DMRS antenna port conflict'.

[0294] It should be understood that for Example 3, as a possible alternative, p represents the number of the first SS set, or p represents the number of the first BWP, or p represents the identifier of the first terminal device, etc., which is not limited in this application.

[0295] It should be added that DMRS antenna port conflict can be understood as different terminal devices using the same DMRS antenna port to receive PDCCH. For example, N = 8, the first terminal device's n RNTI =1, n of the second terminal device RNTI = 9. In this case, the DMRS antenna port determined by the first terminal device based on Example 1 is the same as the DMRS antenna port determined by the second terminal device based on Example 1, which means that a DMRS antenna port conflict occurs.

[0296] In some embodiments, such as in a MU-MIMO transmission scenario, as shown in FIG19 , the present application further includes the following steps:

[0297] S511: The network device determines L′ DMRS antenna ports from N DMRS antenna ports.

[0298] The network device and the N DMRS antenna ports can be found in the introduction of S501 and will not be described in detail.

[0299] Wherein, any one of the L' DMRS antenna ports is different from any one of the L DMRS antenna ports. L' is a positive integer less than or equal to N.

[0300] S512: The network device sends a second PDCCH to the second terminal device via the L' DMRS antenna ports. Correspondingly, the second terminal device receives the second PDCCH from the network device via the L' DMRS antenna ports.

[0301] The second PDCCH includes data information of the second PDCCH and a DMRS of the second PDCCH.

[0302] For example, for the DMRS of the second PDCCH, the network device sends the DMRS of the second PDCCH to the second terminal device through at least one of the time domain resources, frequency domain resources, or OCC associated with L' DMRS antenna ports, and L' DMRS antenna ports. For details, see the introduction of S502 and will not be repeated here.

[0303] For the data information of the second PDCCH, the network device sends the data information of the second PDCCH to the second terminal device by sending the L' antenna ports of the DMRS of the second PDCCH, instead of using any one of the time domain resources, frequency domain resources and OCC associated with the L' DMRS antenna ports to send the data information of the second PDCCH to the second terminal device. For details, see the introduction of S502 and will not be repeated here.

[0304] It should be noted that S511 and S512 are optional steps. For example, when L is less than N, the network device may perform S511 and S512. When L is equal to N, the network device may not perform S511 and S512, thereby helping to improve PDCCH demodulation performance.

[0305] It is understood that in each of the above embodiments, the methods and / or steps implemented by the network device may also be implemented by components applicable to the network device (e.g., processor, chip, chip system, circuit, logic module, or software); and the methods and / or steps implemented by the terminal device may also be implemented by components applicable to the terminal device (e.g., processor, chip, chip system, circuit, logic module, or software). The chip system may be composed of a chip, or may include a chip and other discrete components.

[0306] It is understandable that, in order to realize the above functions, the communication device includes hardware structures and / or software modules corresponding to the execution of each function. It should be easily appreciated by those skilled in the art that, in combination with the units and algorithm steps of each example described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0307] The embodiment of the present application can divide the functional modules of the communication device according to the above method embodiment. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one processing module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. It should be pointed out that the division of modules in the embodiment of the present application is schematic and is only a logical functional division. In actual implementation, there may be other division methods.

[0308] 20 shows a schematic structural diagram of a communication device 2000. The communication device 2000 includes a processing module 2001 and a transceiver module 2002. The communication device 2000 can be used to implement the functions of the above-mentioned network device or terminal device.

[0309] In some embodiments, the communication device 2000 may further include a storage module (not shown in FIG. 20 ) for storing program instructions and data.

[0310] In some embodiments, the transceiver module 2002, which may also be referred to as a transceiver unit, is configured to implement a transmitting and / or receiving function. The transceiver module 2002 may be composed of a transceiver circuit, a transceiver, a transceiver, or a communication interface.

[0311] In some embodiments, the transceiver module 2002 may include a receiving module and a sending module, which are respectively used to execute the receiving and sending steps performed by the network device or terminal device in the above method embodiment, and / or used to support other processes of the technology described in this document; the processing module 2001 may be used to execute the processing steps (such as determination, etc.) performed by the network device or terminal device in the above method embodiment, and / or used to support other processes of the technology described in this document.

[0312] Among them, all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module and will not be repeated here.

[0313] Optionally, in this application, "the transceiver module receives / sends information" can also be understood as the processing module receiving / sending information via the transceiver module. "The processing module receives / sends information via the transceiver module" can also be understood as the processing module controlling the transceiver module to receive / send information. Alternatively, "the processing module sends information via the transceiver module" can be understood as the processing module outputs information to the transceiver module, which then sends the information; "the processing module receives information via the transceiver module" can be understood as the transceiver module receiving the information and inputting the information to the processing module.

[0314] In the present application, the communication device 2000 may be presented in the form of functional modules divided in an integrated manner. The "module" here may refer to a specific application-specific integrated circuit (ASIC), a circuit, a processor and memory that executes one or more software or firmware programs, an integrated logic circuit, and / or other devices that can provide the above functions.

[0315] In some embodiments, when the communication device 2000 in Figure 20 is a chip or a chip system, the function / implementation process of the transceiver module 2002 can be implemented through the input and output interface (or communication interface) of the chip or chip system, and the function / implementation process of the processing module 2001 can be implemented through the processor (or processing circuit) of the chip or chip system.

[0316] Since the communication device 2000 provided in this embodiment can execute the above method, the technical effects that can be obtained can refer to the above method embodiments and will not be repeated here.

[0317] As a possible product form, the network device or terminal device described in the embodiments of the present application can also be implemented using the following: one or more field programmable gate arrays (FPGAs), programmable logic devices (PLDs), controllers, state machines, gate logic, discrete hardware components, any other suitable circuits, or any combination of circuits that can perform the various functions described throughout this application.

[0318] As another possible product form, the network device or terminal device described in the embodiment of the present application can be implemented by a general bus architecture. For ease of explanation, refer to Figure 21, which is a structural diagram of a communication device 2100 provided in an embodiment of the present application, wherein the communication device 2100 includes a processor 2101 and a transceiver 2102. The communication device 2100 can be a network device, or a chip or chip system therein; or, the communication device 2100 can be a terminal device, or a chip or module therein. Figure 21 only shows the main components of the communication device 2100. In addition to the processor 2101 and the transceiver 2102, the communication device 2100 may further include a memory 2103, and an input and output device (not shown).

[0319] Optionally, the processor 2101 is primarily used to process communication protocols and communication data, as well as control the entire communication device, execute software programs, and process software program data. The memory 2103 is primarily used to store software programs and data. The transceiver 2102 may include a radio frequency circuit and an antenna. The radio frequency circuit is primarily used to convert baseband signals into radio frequency signals and process radio frequency signals. The antenna is primarily used to transmit and receive radio frequency signals in the form of electromagnetic waves. Input and output devices, such as a touch screen, display, and keyboard, are primarily used to receive user input and output data to the user.

[0320] Optionally, the processor 2101 , the transceiver 2102 , and the memory 2103 may be connected via a communication bus.

[0321] It should be noted that the memory 2103 may exist independently of the processor 2101 or may be integrated with the processor 2101. The memory 2103 may be located within the communication device 2100 or outside the communication device 2100, without limitation.

[0322] When the communication device is turned on, the processor 2101 can read the software program in the memory 2103, interpret and execute the instructions of the software program, and process the data of the software program. When data needs to be sent wirelessly, the processor 2101 performs baseband processing on the data to be sent and outputs the baseband signal to the radio frequency circuit. The radio frequency circuit performs radio frequency processing on the baseband signal and then transmits the radio frequency signal to the outside in the form of electromagnetic waves through the antenna. When data is sent to the communication device, the radio frequency circuit receives the radio frequency signal through the antenna, converts the radio frequency signal into a baseband signal, and outputs the baseband signal to the processor 2101. The processor 2101 converts the baseband signal into data and processes the data.

[0323] In another implementation, the RF circuit and antenna may be provided independently of the processor performing baseband processing. For example, in a distributed scenario, the RF circuit and antenna may be remotely arranged independent of the communication device.

[0324] In some embodiments, in terms of hardware implementation, those skilled in the art may conceive that the above-mentioned communication device 2000 may take the form of the communication device 2100 shown in FIG. 21 .

[0325] As an example, the functions / implementation process of the processing module 2001 in FIG20 can be implemented by the processor 2101 in the communication device 2100 shown in FIG21 calling the computer-executable instructions stored in the memory 2103. The functions / implementation process of the transceiver module 2002 in FIG20 can be implemented by the transceiver 2102 in the communication device 2100 shown in FIG21.

[0326] As another possible product form, the network device or terminal device in the present application may adopt the structure shown in Figure 22, or include the components shown in Figure 22. Figure 22 is a schematic diagram of the structure of a communication device 2200 provided in the present application.

[0327] As shown in FIG22 , a communication device 2200 includes at least one processor 2201. Optionally, the communication device further includes a communication interface 2202.

[0328] When the program instructions are executed in the at least one processor 2201, the apparatus 2200 can implement the method provided in any of the aforementioned embodiments and any possible designs thereof. Alternatively, the processor 2201 implements the method provided in any of the aforementioned embodiments and any possible designs thereof through logic circuits or by executing code instructions.

[0329] The communication interface 2202 can be used to receive program instructions and transmit them to the processor. Alternatively, the communication interface 2202 can be used for the communication device 2200 to communicate with other communication devices, such as exchanging control signaling and / or service data. Exemplarily, the communication interface 2202 can be used to receive signals from devices other than the communication device 2200 and transmit them to the processor 2201, or to send signals from the processor 2201 to other communication devices other than the communication device 2200.

[0330] Optionally, the communication interface 2202 may be a code and / or data read and write interface circuit, or the communication interface 2202 may be a signal transmission interface circuit between a communication processor and a transceiver, or a pin of a chip.

[0331] Optionally, the communication device 2200 may further include at least one memory 2203, which may be used to store required program instructions and / or data.

[0332] It should be noted that the memory 2203 may exist independently of the processor 2201 or may be integrated with the processor 2201. The memory 2203 may be located within the communication device 2200 or outside the communication device 2200, without limitation.

[0333] Optionally, the communication device 2200 may further include a power supply circuit 2204, which may be used to supply power to the processor 2201. The power supply circuit 2204 may be located in the same chip as the processor 2201, or in another chip other than the chip where the processor 2201 is located.

[0334] Optionally, the communication device 2200 may further include a bus 2205 , and various parts of the communication device 2200 may be interconnected via the bus 2205 .

[0335] In some embodiments, in terms of hardware implementation, those skilled in the art may conceive that the communication device 2000 shown in FIG. 20 may take the form of the communication device 2200 shown in FIG. 22 .

[0336] As an example, the functions / implementation process of the processing module 2001 in FIG20 can be implemented by the processor 2201 in the communication device 2200 shown in FIG22 calling the computer-executable instructions stored in the memory 2203. The functions / implementation process of the transceiver module 2002 in FIG20 can be implemented by the communication interface 2202 in the communication device 2200 shown in FIG22.

[0337] It should be noted that the structure shown in FIG22 does not constitute a specific limitation on the network device or terminal device. For example, in other embodiments of the present application, the network device or terminal device may include more or fewer components than shown in the figure, or combine or split certain components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0338] Optionally, the processor in the present application may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components, etc. A general-purpose processor may be a microprocessor, or the processor may be any conventional processor, etc.

[0339] Optionally, the memory in the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of random access memory (RAM) are available, such as static RAM (SRAM), dynamic random access memory (DRAM), synchronous DRAM (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), or direct rambus RAM (DR RAM).

[0340] Optionally, the power supply circuit described in the embodiment of the present application includes but is not limited to at least one of the following: a power supply line, a power supply subsystem, a power management chip, a power consumption management processor, or a power consumption management control circuit.

[0341] In some embodiments, an embodiment of the present application further provides a communication device, which includes a processor for implementing the method in any of the above method embodiments.

[0342] As a possible implementation, the communication device further includes a memory. The memory is used to store necessary computer programs and data. The computer program may include instructions, and the processor may invoke the instructions in the computer program stored in the memory to instruct the communication device to execute any of the above-described method embodiments. Of course, the memory may not be located in the communication device.

[0343] As another possible implementation, the communication device also includes an interface circuit, which is a code / data read / write interface circuit, and the interface circuit is used to receive computer execution instructions (computer execution instructions are stored in a memory, may be read directly from the memory, or may pass through other devices) and transmit them to the processor.

[0344] As another possible implementation, the communication device further includes a communication interface, where the communication interface is used to communicate with a module outside the communication device.

[0345] It can be understood that the communication device can be a chip or a chip system. When the communication device is a chip system, it can be composed of chips or include chips and other discrete devices. The embodiments of the present application do not specifically limit this.

[0346] The present application also provides a computer-readable storage medium having a computer program or instruction stored thereon, which implements the functions of any of the above method embodiments when executed by a computer.

[0347] The present application also provides a computer program product, which implements the functions of any of the above method embodiments when executed by a computer.

[0348] Those skilled in the art will appreciate that, for the sake of convenience and brevity of description, the specific working processes of the above-described systems, devices, and units may refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0349] It is understood that the systems, devices, and methods described in this application may also be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection shown or discussed may be through some interface, indirect coupling or communication connection of devices or units, and may be electrical, mechanical, or other forms.

[0350] The units described as separate components may or may not be physically separate, i.e., they may be located in one place or distributed across multiple network units. Components shown as units may or may not be physical units. Some or all of these units may be selected to achieve the objectives of this embodiment as needed.

[0351] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0352] In the above embodiments, all or part of the embodiments may be implemented by software, hardware, firmware, or any combination thereof. When implemented using a software program, all or part of the embodiments may be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present application are generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. 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 via a wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) method. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more media integrated therein. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a DVD), or a semiconductor medium (eg, a solid state drive (SSD)). In the embodiment of the present application, the computer may include the aforementioned device.

[0353] Although the present application is described herein in conjunction with various embodiments, in the process of implementing the claimed application, those skilled in the art can understand and implement other changes to the disclosed embodiments by reviewing the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude multiple situations. A single processor or other unit can implement several functions listed in the claims. Certain measures are recorded in different dependent claims, but this does not mean that these measures cannot be combined to produce good results.

Claims

1. A communication method, characterized in that: include: Determine L DMRS antenna ports from N demodulation reference signal DMRS antenna ports, the N DMRS antenna ports are used for physical downlink control channel PDCCH transmission, and any two DMRS antenna ports among the N DMRS antenna ports are orthogonally multiplexed by at least one of the following: time division multiplexing TDM, frequency division multiplexing FDM, or code division multiplexing CDM; N is a positive integer greater than or equal to 2, and L is a positive integer less than or equal to N; The DMRS of the first PDCCH is sent through the L DMRS antenna ports.

2. The method according to claim 1, characterized in that In the case where orthogonal multiplexing is performed between any two DMRS antenna ports among the N DMRS antenna ports through the CDM, Different frequency-domain orthogonal mask codes OCC and / or different time-domain OCC are associated between any two DMRS antenna ports among the N DMRS antenna ports.

3. The method according to claim 1, characterized in that In the case where orthogonal multiplexing is performed between any two DMRS antenna ports among the N DMRS antenna ports through the CDM and the FDM, The N DMRS antenna ports belong to at least two CDM groups, and each of the at least two CDM groups includes a portion of the N DMRS antenna ports; Different frequency domain OCCs and / or different time domain OCCs are associated between any two DMRS antenna ports in any one CDM group of the at least two CDM groups; Different frequency domain resources are associated between any two CDM groups of the at least two CDM groups.

4. The method according to any one of claims 1 to 3, characterized in that The transmission resources of the first PDCCH include multiple resource element groups REGs, each of the multiple REGs includes M first resource elements RE, and the M first REs are used to carry the DMRS of the PDCCH, where M is a positive integer greater than 3; Each of the multiple REGs includes one orthogonal frequency division multiplexing OFDM symbol in the time domain and one resource block RB in the frequency domain.

5. The method according to any one of claims 1 to 3, characterized in that: The time domain resources of the first PDCCH include K symbols, and the K symbols include a first symbol and a second symbol; K is a positive integer greater than or equal to 2; The first PDCCH includes data information of the first PDCCH and a DMRS of the first PDCCH; The data information of the first PDCCH occupies the first symbol, and the DMRS of the first PDCCH occupies the second symbol.

6. The method according to claim 2 or 3, characterized in that: The length of the frequency domain OCC is 2 or 4, and the length of the time domain OCC is 2 or 4.

7. The method according to any one of claims 1 to 6, characterized in that The value of N includes 2 T Or 3*Q, T and Q are positive integers.

8. The method according to any one of claims 1 to 7, characterized in that The method further comprises: Sending the first message; The first information indicates the L antenna ports; The first information is carried in one of the following: radio resource control RRC signaling, system broadcast information block SIB, downlink control information DCI, or media access control layer control element MAC CE.

9. The method according to claim 8, characterized in that The first information indicating the L antenna ports includes: The first information indicates that the first terminal device uses the L DMRS antenna ports in a first search space set SS set to detect the first PDCCH; The first SS set is all SS sets associated with all control resource sets CORESET of the first terminal device; Alternatively, the first SS set is all SS sets associated with all CORESETs on the first bandwidth part BWP, and the first BWP is one of all BWPs of the first terminal device; Alternatively, the first SS set is all SS sets associated with the first CORESET, and the first CORESET is one CORESET of all CORESETs of the first terminal device; Alternatively, the first SS set is one SS set among all SS sets of the first terminal device.

10. The method according to claim 8, characterized in that The first information indicating the L antenna ports includes: The first information indicates that the first terminal device uses the L DMRS antenna ports to detect the first PDCCH in all SS sets associated with a first CORESET group, where the first CORESET group is one CORESET group among all CORESET groups of the first terminal device; Alternatively, the first information indicates that the first terminal device uses the L DMRS antenna ports on a first SS set group to detect the first PDCCH, and the first SS set group is one SS set group among all SS set groups of the first terminal device.

11. The method according to any one of claims 8 to 10, characterized in that: The DCI corresponds to a first terminal device group, and the first terminal device group includes at least one terminal device; The first information is carried in a first information block of the DCI, and the first information block corresponds to one or more terminal devices in the first terminal device group, and the one or more terminal devices include a first terminal device.

12. The method according to any one of claims 1 to 7, characterized in that The L DMRS antenna ports are determined according to a radio network temporary identifier RNTI of the first terminal device; or, The L DMRS antenna ports are determined according to the radio network temporary identifier RNTI of the first terminal device and the number of the first time unit, or, The L DMRS antenna ports are determined according to the radio network temporary identifier RNTI of the first terminal device, the number of the first time unit and the number of the first CORESET.

13. The method according to claim 12, characterized in that L＝1； The numbering of the L DMRS antenna ports satisfies: n RNTI mod N; where n RNTI represents the value of the RNTI; or, The numbering of the L DMRS antenna ports satisfies: Y -1 =n RNTI ; where n RNTI represents the value of the RNTI, represents the number of the first time unit, where A and D are positive integers; or, The numbering of the L DMRS antenna ports satisfies: Y p,-1 =n RNTI ; where n RNTI represents the value of the RNTI, represents the number of the first time unit, p represents the number of the first CORESET, D is a positive integer, A p is a positive integer determined according to p.

14. The method according to any one of claims 1 to 13, characterized in that The method further comprises: Determine L' DMRS antenna ports from the N DMRS antenna ports, any one of the L' DMRS antenna ports is different from any one of the L DMRS antenna ports; L' is a positive integer less than or equal to N; A DMRS of a second PDCCH is transmitted through the L′ DMRS antenna ports, where the second PDCCH is different from the first PDCCH.

15. A communication method, characterized in that: include: Determine L demodulation reference signal DMRS antenna ports, where the L DMRS antenna ports are one or more DMRS antenna ports among N DMRS antenna ports, where the N DMRS antenna ports are used for physical downlink control channel PDCCH transmission, and any two DMRS antenna ports among the N DMRS antenna ports are orthogonally multiplexed through at least one of the following: time division multiplexing TDM, frequency division multiplexing FDM, or code division multiplexing CDM; N is a positive integer greater than or equal to 2, and L is a positive integer less than or equal to N; A DMRS of a first PDCCH is received through the L DMRS antenna ports.

16. The method according to claim 15, characterized in that The method further comprises: receiving a first message; The first information indicates the L antenna ports; The first information is carried in one of the following: radio resource control RRC signaling, system broadcast information block SIB, downlink control information DCI, or media access control layer control element MAC CE.

17. A communication device, characterized in that: The communication device is used to implement the method according to any one of claims 1 to 14.

18. The communication device according to claim 17, characterized in that: The communication device includes a network device or a chip.

19. A communication device, characterized in that: The communication device is used to implement the method according to claim 15 or 16.

20. The communication device according to claim 19, characterized in that The communication device includes a terminal device or a chip.

21. A computer-readable storage medium storing a computer program or instruction, characterized in that: When the computer program or instruction is executed, the method according to any one of claims 1 to 14 is implemented, or the method according to claim 15 or 16 is implemented.

22. A computer program product, characterized in that When the computer program product is executed, the method according to any one of claims 1 to 14 is executed, or the method according to claim 15 or 16 is executed.

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