Demodulation reference signal transceiving method and apparatus

Abstract

The present application relates to the field of communications, and provides a demodulation reference signal (DMRS) transceiving method and apparatus. A DMRS can be mapped to more antenna ports, such that in a multi-user scenario, when a terminal device demodulates a data stream having a large number of spatial layers on the basis of the DMRS, the demodulation performance is good. The method comprises: acquiring a first time domain resource, the first time domain resource being used for transmitting first-type DMRSs, the first time domain resource comprising N sub-time domain resources, antenna ports corresponding to first-type DMRSs received on any two of the N sub-time domain resources being different, time units where any two of the N sub-time domain resources are located being different, and N being greater than or equal to 2; and receiving first-type DMRSs from a network device on the first time domain resource, the first-type DMRSs being used for demodulating data from the network device, and data corresponding to the same antenna port in the data being transmitted in N time units where the N time domain sub-resources are located.

Description

Demodulation reference signal transceiving method and apparatus

[0001] The present application claims priority from the Chinese patent application No. 202410874147.7 filed on July 01, 2024, and entitled "Demodulation reference signal transceiving method and apparatus", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] Embodiments of the present application relate to the field of communications, in particular to a demodulation reference signal transceiving method and apparatus in the field of communications. BACKGROUND

[0003] A demodulation reference signal (DMRS) can be used for channel estimation of a physical channel and demodulation of uplink and downlink data. Therefore, the data transmission of multiple physical channels is accompanied by the transmission of DMRS. For example, a network device can configure a physical downlink shared channel (PDSCH) DMRS, so that a terminal device can demodulate data transmitted through a PDSCH based on the PDSCH DMRS.

[0004] In order to support more efficient multi-antenna technologies, such as multi-user multiple input multiple output (MU-MIMO) and single-user multiple input multiple output (SU-MIMO), etc., the DMRS can be mapped to more antenna ports through code division multiplexing, etc.

[0005] However, such a method can still result in a small number of antenna ports mapped by the DMRS, thereby affecting the data demodulation performance. SUMMARY

[0006] The present application provides a demodulation reference signal transceiving method and apparatus, so that the number of antenna ports mapped by the DMRS is large, thereby helping to improve the data demodulation performance of the terminal device.

[0007] In a first aspect, a method for receiving a demodulation reference signal is provided. The method comprises: obtaining a first time domain resource, the first time domain resource being used for transmitting a first type of demodulation reference signal (DMRS), the first time domain resource comprising N sub-time domain resources, any two of the N sub-time domain resources being different in time unit, and any two of the N sub-time domain resources corresponding to different antenna ports, N being greater than or equal to 2; and receiving, from a network device, the first type of DMRS on the first time domain resource, the first type of DMRS being used for demodulating data from the network device, data corresponding to a same antenna port being transmitted within N time units.

[0008] In a possible implementation, the method is performed by a first communication apparatus. The first communication apparatus can be a terminal device, or a chip or circuit applicable to a terminal device, etc.

[0009] The method for receiving a demodulation reference signal provided in the present application can be used for the network device to configure the first type of DMRS, and the time domain resource of the DMRS of this type comprises N sub-time domain resources. Since the DMRS transmitted by any two of the N sub-time domain resources corresponds to different antenna ports, and N is greater than or equal to 2. In this way, as the number of the N time units increases, the number of the antenna ports to which the first type of DMRS is mapped can be doubled, so that the first type of DMRS can be mapped to more antenna ports. In a multi-user scenario, and in various scenarios where the channel changes slowly, the first type of DMRS can be used for demodulating more data streams with more spatial division multiplexing, which helps to improve the demodulation performance of the first communication apparatus on the data in the multi-user scenario.

[0010] In combination with the first aspect, in some embodiments of the first aspect, the method further comprises: receiving first information from the network device, the first information being used for indicating that the first type of DMRS is activated or indicating that the received DMRS is the first type of DMRS.

[0011] In this way, the first communication apparatus can determine, based on the first information, that the DMRS configured by the network device is the first type of DMRS, i.e., the first communication apparatus can determine that the DMRS configured by the network device can be used for demodulating data transmitted within the N time units.

[0012] In combination with the first aspect, in some embodiments of the first aspect, the method further comprises: receiving second information from the network device, the second information being used for indicating N.

[0013] In this way, the network device can configure different N in different situations. For example, when there are fewer users and the first type of DMRS needs to be mapped to fewer antenna ports, N can be smaller; when there are more users and the first type of DMRS needs to be mapped to more antenna ports, N can be larger.

[0014] With reference to the first aspect, in some embodiments of the first aspect, the second information is carried in a radio resource control (RRC) message or downlink control information (DCI).

[0015] In this way, the first communication apparatus can determine N based on the RRC message or the DCI, i.e., the first communication apparatus can determine the number of sub-time domain resources included in the first time domain resource, or can determine the N time units.

[0016] With reference to the first aspect, in some embodiments of the first aspect, the method further includes: sending, to the network device, third information, the third information being used to indicate that the first communication apparatus supports the first type of DMRS.

[0017] In this way, the network device can determine that the first communication apparatus supports the first type of DMRS, so that the network device will not configure the first type of DMRS for the first communication apparatus when the first communication apparatus does not support the use of the first type of DMRS, thereby reducing the case of invalid DMRS configuration of the network device.

[0018] With reference to the first aspect, in some embodiments of the first aspect, the third information is carried in user equipment (UE) capability information.

[0019] In this way, the network device can determine whether the first communication apparatus supports the first type of DMRS based on the UE capability information. Moreover, the network device can also request the UE capability information from the first communication apparatus through a UE capability request or the like, so that the network device can determine whether the first communication apparatus supports the first type of DMRS before configuring the first type of DMRS.

[0020] The second aspect provides another method for transmitting a demodulation reference signal (DMRS), which includes: determining a first type of DMRS; and transmitting the first type of DMRS to a terminal device on a first time domain resource, the first time domain resource including N sub-time domain resources, the first type of DMRS transmitted on any two of the N sub-time domain resources corresponding to different antenna ports, any two of the N sub-time domain resources being located in different time units, N being greater than or equal to 2, the first type of DMRS being used for demodulating data transmitted to the terminal device, data corresponding to a same antenna port in the data being transmitted within N time units in which the N sub-time domain resources are located.

[0021] In a possible implementation, the method is performed by a second communication apparatus. The second communication apparatus can be a network device, or a chip or circuit applicable to a network device, etc.

[0022] In some embodiments of the second aspect, the method further comprises: sending, to the terminal device, first information, the first information being used to indicate that the first type of DMRS is activated or to indicate that the configured DMRS is the first type of DMRS.

[0023] In some embodiments of the second aspect, the method further comprises: sending, to the terminal device, second information, the second information being used to indicate N.

[0024] In some embodiments of the second aspect, the second information is carried in a radio resource control (RRC) message or downlink control information (DCI).

[0025] In some embodiments of the second aspect, the method further comprises: receiving, from the terminal device, third information, the third information being used to indicate that the terminal device supports the first type of DMRS.

[0026] In some embodiments of the second aspect, the third information is carried in an RRC message or DCI.

[0027] In a third aspect, a communication apparatus is provided, which is configured to execute the method in any possible implementation of the first aspect or the second aspect. Specifically, the communication apparatus comprises modules for executing the method in any possible implementation of the first aspect or the second aspect.

[0028] In a fourth aspect, another communication apparatus is provided, which comprises a processor and a memory coupled to the processor. The processor is configured to execute instructions stored in the memory to implement the method in any possible implementation of the first aspect or the second aspect. Optionally, the communication apparatus further comprises the memory. Optionally, the communication apparatus further comprises a communication interface, and the processor is coupled to the communication interface.

[0029] In one implementation, the communication apparatus is a terminal device or a network device. When the communication apparatus is the terminal device or the network device, the communication interface can be a transceiver, or an input / output interface.

[0030] In another implementation, the communication apparatus is a chip applicable in a terminal device or a network device. When the communication apparatus is the chip applicable in the terminal device or the network device, the communication interface can be an input / output interface.

[0031] In a fifth aspect, a processor is provided, which comprises an input circuit, an output circuit and a processing circuit. The processing circuit is configured to receive a signal through the input circuit and transmit a signal through the output circuit, so that the processor executes the method in any possible implementation of the first aspect or the second aspect.

[0032] In the implementation process, the processor can be a chip, the input circuit can be an input pin, the output circuit can be an output pin, and the processing circuit can be a transistor, a gate circuit, a flip-flop, and various logic circuits. The input signal received by the input circuit can be received and input by, for example but not limited to, a receiver, the output signal output by the output circuit can be output to and transmitted by, for example but not limited to, a transmitter, and the input circuit and the output circuit can be the same circuit which is used as the input circuit and the output circuit at different times. The embodiments of the present application do not limit the specific implementation of the processor and various circuits.

[0033] In a sixth aspect, a communication apparatus is provided, which includes a processor and a memory. The processor is configured to read instructions stored in the memory, and can receive signals through a receiver and transmit signals through a transmitter to perform the method in any possible implementation of the first aspect or the second aspect.

[0034] Optionally, the processor is one or more, and the memory is one or more.

[0035] Optionally, the memory can be integrated with the processor, or the memory and the processor can be separately arranged.

[0036] In the implementation process, the memory can be a non-transitory memory, for example, a read only memory (ROM), which can be integrated with the processor on the same chip or arranged separately on different chips. The type of the memory and the arrangement of the memory and the processor are not limited in the present application.

[0037] It should be understood that the related data interaction process, for example, the process of transmitting the indication information can be the process of outputting the indication information from the processor, and the process of receiving the capability information can be the process of receiving the input capability information by the processor. Specifically, the processed output data can be output to the transmitter, and the input data received by the processor can come from the receiver. The transmitter and the receiver can be collectively referred to as a transceiver.

[0038] The communication apparatus in the sixth aspect can be a chip, and the processor can be implemented by hardware or software. When implemented by hardware, the processor can be a logic circuit or an integrated circuit. When implemented by software, the processor can be a general-purpose processor which reads software codes stored in the memory to implement the processor. The memory can be integrated in the processor or exist independently.

[0039] In a seventh aspect, a computer program product is provided, which includes a computer program (which can also be referred to as code or instructions) that, when executed by a computer, causes the computer to perform the method in any possible implementation of the first aspect or the second aspect.

[0040] In an eighth aspect, a computer-readable storage medium is provided, which stores a computer program (which can also be referred to as code or instructions) that, when executed on a computer, causes the computer to perform the method in any possible implementation of the first aspect or the second aspect. BRIEF DESCRIPTION OF DRAWINGS

[0041] FIG. 1 is a schematic diagram of a PDSCH-DMRS of a mapping type A;

[0042] FIG. 2 is a schematic diagram of a PDSCH-DMRS of a mapping type B;

[0043] FIG. 3 is a schematic diagram of a PDSCH-DMRS of a type 1;

[0044] FIG. 4 is a schematic diagram of a PDSCH-DMRS of a type 2;

[0045] FIG. 5 is a schematic diagram of a PDCCH-DMRS;

[0046] FIG. 6 is a schematic diagram of a communication system to which embodiments of the present application are applicable;

[0047] FIG. 7 is a schematic diagram of a PDSCH-DMRS;

[0048] FIG. 8 is a schematic diagram of another PDSCH-DMRS;

[0049] FIG. 9 is a schematic diagram of yet another PDSCH-DMRS;

[0050] FIG. 10 is a schematic diagram of a first type of DMRS according to a first embodiment of the present application;

[0051] FIG. 11 is a schematic diagram of a second type of DMRS according to a second embodiment of the present application;

[0052] FIG. 12 is a schematic diagram of a method of transmitting and receiving a demodulation reference signal according to an embodiment of the present application;

[0053] FIG. 13 is a schematic diagram of a third type of DMRS according to a third embodiment of the present application;

[0054] FIG. 14 is a schematic diagram of a fourth type of DMRS according to a fourth embodiment of the present application;

[0055] FIG. 15 is a schematic diagram of a fifth first-type DMRS according to an embodiment of the present application;

[0056] FIG. 16 is a schematic block diagram of a communication apparatus according to an embodiment of the present application;

[0057] FIG. 17 is a schematic block diagram of another communication apparatus according to an embodiment of the present application;

[0058] FIG. 18 is a schematic block diagram of an O-RAN system according to an embodiment of the present application;

[0059] FIG. 19 is a schematic block diagram of a network element function division and protocol layer structure of an O-RAN device according to an embodiment of the present application. DETAILED DESCRIPTION

[0060] The technical solutions in the present application will be described below with reference to the drawings.

[0061] In the embodiments of the present application, the terms "first", "second", and the like are used to distinguish between items or objects that have substantially the same function and effect. For example, the first value and the second value are merely used to distinguish between different values and do not limit the order. Those skilled in the art can understand that the terms "first", "second", and the like do not limit the number and execution order, and the terms "first", "second", and the like do not necessarily mean different.

[0062] It should be noted that the words "exemplary" or "for example" in the embodiments of the present application are used to represent an example, illustration, or description. Any embodiment or design scheme described as "exemplary" or "for example" in the present application should not be interpreted as more preferred or more advantageous than other embodiments or design schemes. Rather, the use of the words "exemplary" or "for example" is intended to present the relevant concept in a specific manner.

[0063] In the embodiments of the present application, "at least one" means one or more, and "multiple" means two or more. The association relationship between the associated objects is described by "and / or", which means that there can be three relationships, for example, A and / or B, which can represent the following cases: A exists alone, A and B exist together, and B exists alone, where A and B can be singular or plural. The character "or" generally represents an "or" relationship between the associated objects. "At least one" or similar expressions mean any combination of these items, including any combination of single item or multiple items. For example, at least one of a, b, or c can represent a, b, c, a-b, a-c, b-c, or a-b-c, where a, b, and c can be single or multiple.

[0064] The technical solutions of the embodiments of the present application can be applied to various communication systems, for example: a long term evolution (LTE) system, an LTE frequency division duplex (FDD) system, an LTE time division duplex (TDD), a worldwide interoperability for microwave access (WiMAX) communication system, a 5th generation (5G) system or new radio (NR), a future communication system, and the like.

[0065] The terminal device in the embodiments of the present application can also be referred to as a user equipment (UE), a mobile station (MS), a mobile terminal (MT), an access terminal, a subscriber unit, a subscriber station, a mobile station, a mobile terminal, a remote station, a remote terminal, a mobile device, a user terminal, a terminal, a wireless communication device, a user agent, or a user device, and the like.

[0066] The terminal device can be a device that provides voice / data connectivity to a user, for example, a handheld device with wireless connection function, a vehicle-mounted device, etc. At present, some examples of terminal devices include: a mobile phone, a tablet computer, a notebook computer, a palm computer, a mobile internet device (MID), a wearable device, a virtual reality (VR) device, an augmented reality (AR) device, a wireless terminal in industrial control, a wireless terminal in self driving, a wireless terminal in remote medical surgery, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, a cellular phone, a cordless phone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device, a wearable device, a terminal device in a 5G network, or a terminal device in a future evolved public land mobile network (PLMN), etc., which are not limited in the present application.

[0067] By way of example, and without limitation, in the present application, the terminal device can be a terminal device in an internet of things (IoT) system. The internet of things is an important component of future information technology development, and its main technical feature is to connect objects through communication technology and network, so as to realize the intelligent network of man-machine interconnection and object-object interconnection. Illustratively, the terminal device in the embodiments of the present application can be a wearable device. The wearable device can also be referred to as a wearable smart device, which is a general term for smart devices that can be worn, such as glasses, gloves, watches, clothing, and shoes, which are designed and developed by wearable technology. The wearable device is a portable device that can be directly worn on the body or integrated into the user's clothes or accessories. The wearable device is not only a hardware device, but also can realize powerful functions through software support, data interaction, and cloud interaction. The general wearable smart device includes a full function, large size, and can realize complete or partial functions without relying on a smart phone, such as a smart watch or smart glasses, and only focuses on a certain application function, and needs to cooperate with other devices such as a smart phone, such as various smart wristbands, smart jewelry, and the like for monitoring vital signs.

[0068] By way of example, and without limitation, in the embodiments of the present application, the terminal device can also be a terminal device in machine type communication (MTC). In addition, the terminal device can also be a vehicle-mounted module, a vehicle-mounted module, a vehicle-mounted component, a vehicle-mounted chip, or a vehicle-mounted unit, etc. built-in as one or more components or units in a vehicle. The vehicle can implement the method provided in the present application through the built-in vehicle-mounted module, vehicle-mounted module, vehicle-mounted component, vehicle-mounted chip, or vehicle-mounted unit, etc. Therefore, the embodiments of the present application can also be applied to the Internet of Vehicles, such as vehicle to everything (V2X), long term evolution-vehicle (LTE-V), vehicle-to-vehicle (V2V) technology, etc.

[0069] The network device involved in the present application can be a device in communication with a terminal device, which can also be referred to as an access network device or a radio access network device, which can be a transmission reception point (TRP), and can also be an evolved NodeB (eNB or eNodeB) in an LTE system, and can also be a home base station (for example, a home evolved NodeB or home NodeB, HNB), a baseband unit (BBU), and can also be a wireless controller in a cloud radio access network (CRAN) scenario, or the network device can be a relay station, an access point, a vehicle-mounted device, a wearable device, and a network device in a 5G network or a future evolved PLMN network, and can also be an access point (AP) in a WLAN, and can also be a gNB in an NR system, and the network device can also be a city base station, a micro base station, a pico base station, a femto base station, and the like, and the present application does not limit the network device.

[0070] First, some technical terms and symbols involved in the present application are introduced.

[0071] 1. Resource element (RE), resource block (RB), and resource element group (REG) are basic units for describing resource allocation.

[0072] Among them, RE is the smallest resource unit, which represents the combination of one OFDM symbol in the time domain and one subcarrier in the frequency domain.

[0073] RB is a resource unit composed of multiple REs, and usually represents a rectangular area in the time and frequency domains. In the frequency domain, a RB usually contains 12 subcarriers; in the time domain, the length of a RB can be one slot (usually containing 7 or 14 OFDM symbols, depending on the subcarrier spacing).

[0074] REG is a resource unit composed of multiple REs, and is usually used for resource allocation of PDCCH (Physical Downlink Control Channel). An REG usually contains several consecutive REs, and the specific number can be different according to different standards and configurations. For example, in 5G NR, an REG usually contains 12 REs distributed in one OFDM symbol.

[0075] 2. Uplink physical channels, which can include but are not limited to: random access channel (PRACH), uplink control channel (PUCCH), and uplink data channel (PUSCH), etc.

[0076] 3. Uplink reference signals, which can refer to reference signals sent by a terminal device to a network device. Exemplarily, the uplink reference signals can include but are not limited to: sounding reference signal (SRS), de-modulation reference signal (DMRS) of the uplink control channel, de-modulation reference signal (PUSCH-DMRS) of the uplink data channel, phase noise tracking reference signal (PTRS), and uplink positioning signal, etc.

[0077] 4. Downlink physical channels, which can include but are not limited to: physical broadcast channel (PBCH), downlink control channel (PDCCH), and downlink data channel (PDSCH), etc.

[0078] 5. PDSCH, which is a main downlink channel for transmitting user data and can be used to carry actual user data packets, such as web page content, video stream, etc.

[0079] According to different time-domain resources of the PDSCH, the PDSCH can be divided into mapping type A and mapping type B.

[0080] Among them, the mapping type A is: in a time slot, the PDSCH occupies OFDM symbols from the position of OFDM symbols {0, 1, 2, 3}, the symbol length is 3-14 OFDM symbols, and cannot exceed the time slot boundary. The time slot boundary is the boundary between the time slot and the next time slot, and the OFDM symbols occupied by the PDSCH cannot cross to the OFDM symbols in the next time slot.

[0081] It should be understood that, in the embodiments of the present application, the OFDM symbol {0, 1, 2, 3, …} represents the OFDM symbol 0, the OFDM symbol 1, the OFDM symbol 2, or the OFDM symbol 3, and so on. The OFDM symbol a represents the number or index of the OFDM symbol in a slot, a is an integer greater than or equal to 0. For example, in a slot, the OFDM symbols can be numbered in ascending order of integers starting from 0 in time from early to late. For brevity, this will not be repeated hereinafter.

[0082] It should also be understood that the index of the OFDM symbol shown in the embodiments of the present application is only an example, and the index of the OFDM symbol can also be other identifiers, for example, can also be letters or other numerical values, etc. The present application does not make specific limitations on this.

[0083] The mapping type B is: in a slot, the OFDM symbol occupied by the PDSCH starts from the OFDM symbol {0, 1, …, 12} position, the symbol length is 2, 4, or 7 OFDM symbols, and cannot exceed the slot boundary.

[0084] 6. PDCCH, a channel for transmitting control information. It can be used to carry scheduling information and other control information indicating how the terminal device receives and decodes data on the PDSCH. For example, the network device can send downlink control information (DCI) to the terminal device through the PDCCH.

[0085] It should be understood that, in the embodiments of the present application, transmitting the PDSCH can also be understood as transmitting information through the PDSCH; transmitting the PDCCH can also be understood as transmitting information through the PDCCH. For brevity, this will not be repeated hereinafter.

[0086] 7. Downlink control information (DCI), which can be used to indicate: downlink scheduling information, information indicating the way for the terminal device to receive the PDSCH, for example, indicating the PDSCH time-frequency domain resource, the modulation and coding mode of the PDSCH, and the hybrid automatic repeat request (HARQ) parameter, etc.; uplink scheduling information (UL grants), information indicating the way for the terminal device to send the PUSCH; other physical layer control information, for example, slot format indication (SFI), resource pre-emption indication (PI), and power control command, etc. Signaling used to assist the terminal device to receive and send data.

[0087] 8. Downlink reference signal, which can refer to a reference signal sent by a network device to a terminal device. Illustratively, the downlink reference signal can include, but is not limited to, a demodulation reference signal of a downlink control channel (PDCCH-DMRS), a demodulation reference signal of a downlink data channel (PDSCH-DMRS), a phase noise tracking signal, a channel state information reference signal (CSI-RS), a time / frequency tracking reference signal (TRS), a cell reference signal (CRS), and an LTE / NR positioning signal (positioning RS), etc.

[0088] Wherein, the PDCCH-DMRS can also be denoted as PDCCH DMRS, and the PDSCH-DMRS can also be denoted as PDSCH DMRS, which are not specifically limited in the present application.

[0089] It should be understood that the uplink reference signals and downlink reference signals, and the uplink physical channels and downlink physical channels shown above are only examples and should not constitute any limitation on the present application. The uplink reference signals or downlink reference signals can also include more reference signals, and the present application does not exclude the possibility of defining other reference signals in future protocols to achieve the same or similar functions. The uplink physical channels or downlink physical channels can also include more physical channels, and the present application does not exclude the possibility of defining other physical channels in future protocols to achieve the same or similar functions.

[0090] 9. Demodulation reference signal (DMRS), which is used for demodulation of uplink and downlink data in the data transmission process. Except for PRACH, each NR physical channel has a DMRS distributed in the respective resource. For example, the PUSCH-DMRS, PDCCH-DMRS and PDSCH-DMRS shown above.

[0091] DMRS is widely used in various important physical channels, wherein, the PUSCH-DMRS is the DMRS in the PUSCH; the PDCCH-DMRS is the DMRS in the PDCCH; and the PDSCH-DMRS is the DMRS in the PDSCH.

[0092] The DMRS can be divided into front-loaded DMRS and additional DMRS.

[0093] The front-loaded DMRS is a reference signal used for channel estimation and demodulation in a wireless communication system. It is inserted into the data stream before the data is transmitted, so that the receiving end can accurately estimate the channel state, so as to correctly demodulate the received data.

[0094] The additional DMRS is a reference signal added in addition to the front-loaded DMRS to enhance channel estimation and data demodulation performance. They are usually used in more complex transmission scenarios, such as high-mobility users, poor channel conditions, or scenarios requiring higher data rates.

[0095] Taking PDSCH-DMRS as an example, according to the different time domain resources of PDSCH-DMRS, the mapping types of DMRS time domain resources include mapping type A and mapping type B.

[0096] From the perspective of time domain resources, in order to reduce the demodulation and decoding delay, the front-loaded DMRS is located in front of the orthogonal frequency division multiplexing (OFDM) symbol occupied by the PDSCH, and the front-loaded DMRS occupies 1-2 OFDM symbols. Since the front-loaded DMRS is used to demodulate the PDSCH signal, the front-loaded DMRS position also needs to be designed in combination with different PDSCH time domain mapping types.

[0097] 10. Mapping type A, the OFDM symbol occupied by the front-loaded DMRS is relative to the start position of the slot. The front-loaded DMRS of mapping type A can also be understood as the DMRS accompanying the PDSCH transmission of mapping type A.

[0098] Exemplarily, as shown in FIG. 1, the horizontal direction represents the time domain, and from the perspective of the time domain, each grid represents an OFDM symbol; the vertical direction represents the frequency domain, and from the perspective of the frequency domain, each grid represents a subcarrier. In this way, each two-dimensional grid can be understood as a resource element (RE). The PDSCH occupies OFDM symbols 0 to OFDM symbol 13 in a slot; the PDSCH-DMRS occupies OFDM symbol 2.

[0099] 11. Mapping type B, the OFDM symbol occupied by the front-loaded DMRS is relative to the start position of the PDSCH symbol. The PDSCH symbol is the OFDM symbol occupied by the PDSCH in a slot. The front-loaded DMRS of mapping type B can also be understood as the DMRS accompanying the PDSCH transmission of mapping type B.

[0100] Exemplarily, as shown in FIG. 2, the PDSCH occupies OFDM symbol 8 to OFDM symbol 11 in a time slot; the PDSCH occupies 4 symbols in length. The PDSCH-DMRS is the first OFDM symbol in the OFDM symbols occupied by the PDSCH, that is, OFDM symbol 8.

[0101] Taking the PDSCH-DMRS as an example, according to different resource element (RE) mapping densities of the DMRS in the frequency domain resources, the DMRS supports different numbers of antenna ports, and the DMRS can be divided into different DMRS types (DMRS type), which can also be referred to as DMRS configuration types (DMRS configuration type) and the like. The DMRS type can include DMRS type 1 (type 1) and DMRS type 2 (type 2).

[0102] Among them, the DMRS type 1 occupying a single OFDM symbol supports a maximum of 4 antenna ports, and the DMRS type 1 occupying double OFDM symbols supports a maximum of 8 antenna ports; the DMRS type 2 occupying a single OFDM symbol supports a maximum of 6 antenna ports, and the DMRS type 2 occupying double OFDM symbols supports a maximum of 12 antenna ports.

[0103] 12. The DMRS type 1, the DMRS RE is distributed in the frequency domain interval of each OFDM symbol, and the density is 50%, that is, the DMRS of the DMRS type 1 is allocated to the same antenna port every 1 RE interval.

[0104] Exemplarily, as shown in FIG. 3, from the frequency domain angle, the DMRS allocated to the antenna port 1000, the antenna port 1001, the antenna port 1004 and the antenna port 1005 occupies subcarriers 0, 2, 4, 6, 8 and 10 respectively, and occupies subcarriers distributed at an interval of 1 subcarrier; from the RE angle, the occupied RE is distributed at an interval of 1 RE. Similarly, from the frequency domain angle, the DMRS allocated to the antenna port 1002, the antenna port 1003, the antenna port 1006 and the antenna port 1007 occupies subcarriers 1, 3, 5, 7, 9 and 11 respectively, and occupies subcarriers distributed at an interval of 1 subcarrier; from the RE angle, the occupied RE is distributed at an interval of 1 RE.

[0105] Among them, the DMRS RE can be understood as the RE used to carry the DMRS or the RE occupied by the DMRS. The interval of 1 RE means that the interval between the adjacent two REs in the same OFDM symbol is 1 RE.

[0106] 13. DMRS Type 2, within each OFDM symbol, DMRS REs are connected together every two REs, and are spaced 4 REs apart, with a density of about 33.3%, i.e. DMRS of DMRS Type 2 are allocated to the same antenna port every 4 REs apart.

[0107] Exemplarily, as shown in FIG. 4, DMRSs allocated to the antenna port 1000, the antenna port 1001, the antenna port 1006 and the antenna port 1007 occupy subcarriers 0 and 1, and subcarriers 6 and 7, respectively, which occupy adjacent 2 subcarriers (for example, subcarriers 0 and 1 are adjacent 2 subcarriers) and are spaced 4 subcarriers apart (for example, subcarriers 1 and 6 are spaced 4 subcarriers apart) from the perspective of the frequency domain; from the perspective of REs, the occupied REs are two REs connected together and are spaced 4 REs apart. DMRSs allocated to the antenna port 1002, the antenna port 1003, the antenna port 1008 and the antenna port 1009 occupy subcarriers 2 and 3, and subcarriers 8 and 9, respectively, which occupy adjacent 2 subcarriers and are spaced 4 subcarriers apart from the perspective of the frequency domain; from the perspective of REs, the occupied REs are two REs connected together and are spaced 4 REs apart. Similarly, DMRSs allocated to the antenna port 1004, the antenna port 1005, the antenna port 1010 and the antenna port 1011 occupy subcarriers 4 and 5, and subcarriers 10 and 11, respectively, which occupy adjacent 2 subcarriers and are spaced 4 subcarriers apart from the perspective of the frequency domain; from the perspective of REs, the occupied REs are two REs connected together and are spaced 4 REs apart.

[0108] It should be understood that FIG. 3 and FIG. 4 are merely examples, in some possible implementation manners, the number of OFDM symbols occupied by PDSCH-DMRS can be more or less, and the subcarriers occupied by PDSCH-DMRS can also be other subcarriers; in addition, the antenna ports corresponding to PDSCH-DMRS can also be other antenna ports, which are not limited in the present application.

[0109] It should also be understood that, in the embodiments of the present application, the subcarrier y represents the number or index of the subcarrier in a RB in the order from low to high in frequency, and y is an integer greater than or equal to 0. For example, in a RB, the subcarriers y can be numbered in the order from low to high in frequency starting from 0 as an integer. For the sake of brevity, this will not be described in detail hereinafter.

[0110] It should be noted that the subcarrier index shown in the embodiments of the present application is only an example. The subcarrier index can also be other identifiers, for example, it can also be a letter or other numerical value, etc. The present application does not make specific limitations on this.

[0111] 14. Time domain resource of PDCCH-DMRS, PDCCH-DMRS usually occupies the same OFDM symbol as PDCCH. For example, PDCCH occupies OFDM symbol 0 and OFDM symbol 1 of a slot, and PDCCH-DMRS occupies OFDM symbol 0 and OFDM symbol 1 of the slot; or PDCCH occupies OFDM symbol 0 of a slot, and PDCCH-DMRS occupies OFDM symbol 0 of the slot, etc.

[0112] 15. Frequency domain resource of PDCCH-DMRS, PDCCH and PDCCH-DMRS usually support single antenna port transmission. The frequency domain resource of PDCCH-DMRS is usually 3 subcarriers in a REG.

[0113] Exemplarily, as shown in FIG. 5, from the frequency domain point of view, one REG covers subcarriers 0 to 11, a total of 12 subcarriers. The frequency domain resource of PDCCH-DMRS is usually subcarrier 1, subcarrier 5 and subcarrier 9 in subcarriers 0 to 11 covered by one REG. From the RE point of view, in one REG, PDCCH-DMRS occupies 3 REs.

[0114] It should be understood that FIG. 5 is only an example, and in some possible implementations, the frequency domain resource of PDCCH-DMRS can also be other subcarriers, which is not limited in the present application.

[0115] 16. DMRS port: can refer to an antenna port used to transmit DMRS. Each DMRS port can represent an independent channel estimation reference source, usually associated with a specific antenna or antenna group. The design and configuration of DMRS port is particularly important in multiple input multiple output (MIMO) systems, as they directly affect the accuracy of channel estimation and system performance. Usually, each reference signal port will occupy different time-frequency code domain resources to reduce mutual interference. Each reference signal port will correspond to a physical antenna, and the mapping relationship between the DMRS port and the physical antenna needs to be coordinated at the sending end and the receiving end to ensure that the receiving end can correctly identify and use the DMRS for channel estimation.

[0116] 17. Master information block (MIB), a message transmitted on a physical broadcast channel (PBCH), and the terminal device acquires system information block (SIB) information by reading the MIB information. The MIB is used to carry scheduling information of the system information block and the like.

[0117] 18. System message, including various information used by the network device to inform the terminal device about the system, such as network information of the cell in which the terminal device is located, information of the registration area, information of the public channel, and information of other cells and the like related to the system. The system message includes SIB1 and other system information blocks (OSI).

[0118] Among them, SIB1 is used to carry cell selection information, access control information, initial access related channel configuration information and scheduling information of the remaining system information block, and the system information block contains specific data. The system message is carried on a group of radio frames and can be broadcast by a broadcast channel (BCH).

[0119] 19. Orthogonal sequence, which can also be referred to as an orthogonal cover code (OCC), an OCC code or an OCC sequence, etc. It is a coding technology used in a communication system. Its principle is to divide the original information into multiple sub-information and code it, so that each sub-information forms a code word after coding, and the code words are orthogonal to each other, so as to realize efficient transmission and decoding of information.

[0120] 20. Symbol: One or more elements in an orthogonal sequence, where each element can be referred to as a symbol. For example, the orthogonal sequence is: [+1, -1], where +1 is a symbol and -1 is also a symbol.

[0121] 21. Sequence length of the orthogonal sequence: the number of symbols included in the orthogonal sequence. For example, the orthogonal sequence is: [+1, -1], the number of symbols is 1, and the sequence length of the orthogonal sequence is also 2.

[0122] In order to facilitate understanding of the embodiments of the present application, first, the communication system suitable for the embodiments of the present application is described in detail in combination with FIG. 6.

[0123] FIG. 6 is a schematic diagram of a communication system 600 to which embodiments of the present application can be applied. The communication system 600 can include at least one network device, such as the network device 610 shown in FIG. 6, and at least one terminal device, such as the terminal device 620 shown in FIG. 6. The network device 610 and the terminal device 620 can communicate with each other via a wireless link. In one possible scenario, the network device 610 can act as a transmitter and the terminal device 620 can act as a receiver, and the network device 610 can transmit signals to the terminal device 620. In another possible scenario, the network device 610 can act as a receiver and the terminal device 620 can act as a transmitter, and the terminal device 620 can transmit signals to the network device 610.

[0124] FIG. 6 exemplarily shows one network device 610 and one terminal device 620. Optionally, the communication system 600 can include multiple network devices and / or multiple terminal devices. The network device 610 can be a router, a base station, etc., and the terminal device 620 can be a mobile phone, a tablet computer, a smart bracelet, etc., and the embodiments of the present application are not limited in this regard.

[0125] Each of the above communication devices, such as the network device 610 or the terminal device 620 in FIG. 6, can be configured with multiple antennas. The multiple antennas can include at least one transmit antenna for transmitting signals and at least one receive antenna for receiving signals. In addition, each of the communication devices can additionally include a transmitter chain and a receiver chain, which can each include multiple components (such as a processor, a modulator, a multiplexer, a demodulator, a demultiplexer, or an antenna, etc.) related to signal transmission and reception. Thus, the network device 610 and the terminal device 620 can communicate with each other via multiple antenna technology.

[0126] Optionally, the above communication system 600 can further include a network controller, a mobility management entity, and other network entities, and the embodiments of the present application are not limited in this regard.

[0127] It should also be understood that the methods provided by the embodiments of the present application can be applicable to various communication systems including a 5G new radio (NR) system, and the communication system 600 is merely an example. The present application is not limited to a specific architecture of a system to which it is applied, nor to the number and the form of various devices included in each communication system.

[0128] Currently, the terminal device can determine the PDSCH time domain resource through a high layer parameter and DCI. The high layer parameter can be a parameter carried in a system information block 1 (SIB1), an RRC setup message, a security mode command, or an RRC reconfiguration message, and the like.

[0129] For example, the high layer parameter can be carried in a PDSCH-time domain resource allocation list field in any of the above messages.

[0130] The PDSCH-time domain resource allocation list may, for example, include the following information:

[0131] k0 INTEGER (0…32);

[0132] mapping type ENUMERRATED{typeA, typeB};

[0133] start symbol and length INTEGER (0…127).

[0134] Wherein, k0 is the time slot offset interval of PDSCH relative to PDCCH; mapping type is the mapping type; start symbol and length is the starting OFDM symbol and OFDM symbol length of PDSCH.

[0135] The network device can indicate multiple PDSCH-time domain resource allocation list fields to the terminal device through SIB1, RRC setup message, security mode signaling, or RRC configuration message, and the like, for example, 16 PDSCH-time domain resource allocation list fields can be indicated, wherein the high layer parameters (k0, mapping type, starting OFDM symbol of PDSCH, and OFDM symbol length) carried in each PDSCH-time domain resource allocation list field can be different. Therefore, the network device can further indicate the PDSCH time domain resource to the terminal device through DCI, which is the time domain resource indicated by which of the multiple PDSCH-time domain resource allocation list fields.

[0136] It can be understood that the message for carrying the higher layer parameter is sent at a specific time. Therefore, according to the above order of the messages that can carry the higher layer parameter, the terminal device can determine the PDSCH time domain resource based on the higher layer parameter carried in the message acquired last time and the latest DCI. The latest DCI is the DCI acquired by the terminal device at the latest time.

[0137] Exemplarily, before the terminal device parses the SIB1 message, the terminal device can determine the PDSCH time domain resource based on the master information block (MIB) and the latest DCI; after the terminal device parses the SIB1 message and before the terminal device parses the RRC setup message, the terminal device determines the PDSCH time domain resource using the higher layer parameter carried in the SIB1 message and the latest DCI; after the terminal device parses the RRC setup message and before the terminal device parses the RRC configuration message, the terminal device determines the PDSCH time domain resource using the higher layer parameter carried in the RRC setup message and the latest DCI; after the terminal device parses the RRC configuration message, the terminal device can determine the PDSCH time domain resource using the higher layer parameter carried in the RRC configuration message and the latest DCI.

[0138] It should be understood that between the adjacent two times of acquiring the message carrying the higher layer parameter, the terminal device can receive the DCI from the network device multiple times, and the latest DCI is the DCI received by the terminal device at the latest time.

[0139] Since multiple PDSCH time domain resources are configured in the higher layer parameter, the specific PDSCH time domain resource to be used also needs to be determined in combination with the DCI. For example, the terminal device can determine the specific PDSCH time domain resource to be used based on the time domain resource assignment field in the DCI 1_0 or the DCI 1_1.

[0140] It should be understood that the DCI 1_0 or the DCI 1_1 is two formats of the DCI. Among them, the DCI 1_0 can be used for scheduling of downlink data transmission, and can contain control information required for PDSCH resource allocation and decoding. The DCI 1_1 can also be used for scheduling of downlink data transmission, but it is usually used for more complex scenarios, such as carrier aggregation or MIMO configuration, etc. The information contained in the DCI 1_1 is similar to that in the DCI 1_0, but the DCI 1_1 can contain more fields to support complex transmission schemes.

[0141] In addition, based on the mapping type of the PDSCH, the terminal device can determine the front-loaded DMRS time domain resource. For example, in the case of PDSCH time domain resource allocation (mapping type) of type A, the starting OFDM symbol of the PDSCH can be OFDM symbol 0-3, and the starting position of the front-loaded DMRS in the slot is OFDM symbol 2 or OFDM symbol 3. By default, the starting position of the front-loaded DMRS in the slot is OFDM symbol 2; when DMRS-TypeA-Position = 3 in the MIB, the starting position of the front-loaded DMRS in the slot is OFDM symbol 3, where DMRS-TypeA-Position can be understood as a field in the MIB. In the case of PDSCH time domain resource allocation (mapping type) of type B, the starting OFDM symbol of the PDSCH can be OFDM symbol 0-12, and the starting position of the front-loaded DMRS is the first OFDM symbol of the PDSCH; if the first OFDM symbol of the PDSCH belongs to the control resource set (CORESET), the starting position of the front-loaded DMRS is the first OFDM symbol after the last OFDM symbol in the CORESET.

[0142] It should be understood that the control resource set can also be referred to as a control resource set, and the physical resource set for carrying the DCI, such as the RB or RE for carrying the DCI, etc.

[0143] The additional DMRS usually occupies 1-3 OFDM symbols. In a high-speed scenario, the network device can configure the presence or absence of the additional DMRS and the time domain resource of the additional DMRS through the DMRS additional position (DMRS-additional position) field in the high-level parameter.

[0144] Similarly, the terminal device can also determine the PDSCH-DMRS frequency domain resource based on the high-level parameter and the DCI. The high-level parameter may, for example, be a parameter carried in the RRC setup message or the RRC configuration message. For example, the high-level parameter can include the following information:

[0145] DMRS-DownlinkConfig: = SEQUENCE;

[0146] DMRS-type ENUMERRATED{type2};

[0147] DMRS-additional position ENUMERRATED{pos0, pos1, pos3};

[0148] max length ENUMERRATED{len2}.

[0149] Wherein, DMRS-type is used to indicate DMRS type, for example, indicating that the DMRS type is type 2; DMRS-additional position is used to indicate additional DMRS position; max length is used to indicate the maximum number of OFDM symbols occupied by PDSCH-DMRS, for example, len2 is used to indicate that the maximum number of OFDM symbols occupied by PDSCH-DMRS is 2 OFDM symbols.

[0150] Further, the network device can indicate the number of OFDM symbols occupied by PDSCH-DMRS to the terminal device through DCI. The number of OFDM symbols indicated in the DCI is less than or equal to the maximum number of OFDM symbols occupied by PDSCH-DMRS indicated by max length in the high layer parameter. For example, max length is len2, indicating that the maximum number of OFDM symbols occupied by PDSCH-DMRS is 2 OFDM symbols, then the number of OFDM symbols occupied by PDSCH-DMRS indicated by the DCI can be 1 OFDM symbol or 2 OFDM symbols.

[0151] The above shows the way for the terminal device to determine the time-frequency domain resource of PDSCH-DMRS.

[0152] The PDSCH-DMRS configured in the above manner can support up to 8 antenna ports in the case of PDSCH-DMRS being type 1 and occupying 2 OFDM symbols, and can support up to 12 antenna ports in the case of PDSCH-DMRS being type 2 and occupying 2 OFDM symbols.

[0153] Taking the case of PDSCH-DMRS being type 2 and occupying 2 OFDM symbols as an example, PDSCH-DMRS is mapped to 12 antenna ports in the following manner.

[0154] The network device can process PDSCH-DMRS occupying the same time-frequency domain resource through time domain OCC with a length of 2 and frequency domain OCC with a length of 2 respectively.

[0155] Exemplarily, as shown in FIG. 7, the time-frequency domain resources of the 0th group (n=0) and the 1st group (n=1) PDSCH-DMRS shown in (a), (b), (c) and (d) of FIG. 7 are the same, belonging to one code division multiplexing (CDM) group. The time-frequency domain resources occupied by the PDSCH-DMRS in this part are the same and cannot be distinguished by time domain and / or frequency domain, but can only be distinguished by code domain. That is, the DMRS in one CDM group occupies the same time-frequency domain resources and can be distinguished by different OCCs, so that the DMRS in the one CDM group can be mapped to different antenna ports. In this way, the mutual interference between the DMRSs occupying the same time-frequency domain resources is small, thereby being able to improve the spectral efficiency and the reliability of signal transmission.

[0156] In this case, the network device can process the 0th group and the 1st group PDSCH-DMRS by different OOCs respectively, so that the 0th group and the 1st group PDSCH-DMRS are orthogonal to each other, and the 0th group and the 1st group PDSCH-DMRS occupying the same time-frequency domain resources can be mapped to 4 orthogonal antenna ports.

[0157] As shown in (a) of FIG. 7, the 0th group and the 1st group PDSCH-DMRS are processed by using time domain OCC [1, 1] and frequency domain OCC [1, 1]; as shown in (b) of FIG. 7, the 0th group and the 1st group PDSCH-DMRS are processed by using time domain OCC [1, 1] and frequency domain OCC [-1, 1]; as shown in (c) of FIG. 7, the 0th group and the 1st group PDSCH-DMRS are processed by using time domain OCC [1, -1] and frequency domain OCC [1, 1]; as shown in (d) of FIG. 7, the 0th group and the 1st group PDSCH-DMRS are processed by using time domain OCC [1, -1] and frequency domain OCC [-1, 1].

[0158] In this way, the 0th group and the 1st group PDSCH-DMRS occupying the same time-frequency domain resources can be respectively mapped to 4 different antenna ports. That is, the 0th group and the 1st group PDSCH-DMRS can be mapped to: antenna port 0, antenna port 1, antenna port 6 and antenna port 7.

[0159] Since the REs other than the REs occupied by the PDSCH-DMRS of the 0thgroup and the 1stgroup can also be used to carry the PDSCH-DMRS respectively, that is, similar to the PDSCH-DMRS of type 2 shown in FIG. 4, the other REs can also carry the PDSCH-DMRS of two other CDM groups. And the PDSCH-DMRS of each of the other two CDM groups can also be mapped to 4 antenna ports respectively. For example, the PDSCH-DMRS of one of the other two CDM groups can be mapped to: antenna port 2, antenna port 3, antenna port 4, and antenna port 5; and the PDSCH-DMRS of the other of the other two CDM groups can be mapped to: antenna port 8, antenna port 9, antenna port 10, and antenna port 11. In this way, in the case that all the REs shown in FIG. 7 carry the PDSCH-DMRS, the PDSCH-DMRS can be mapped to 12 antenna ports in total.

[0160] It should be understood that in the embodiments of the present application, the antenna port f represents the antenna port corresponding to the number or index f. The index or number of the antenna port shown in the embodiments of the present application is an example. f can be an integer, and the index or number of the antenna port shown in the embodiments of the present application can also be replaced by other values. Alternatively, the number or index f of the antenna port can also be in the form of a letter or the like. The embodiments of the present application do not make specific limitations in this regard.

[0161] In order to improve the system capacity and enable the network device to serve more terminal devices, currently, spatial multiplexing (which can also be referred to as space division) between multiple users can be implemented through technologies such as multi-user multiple input multiple output (MU-MIMO). In this way, through spatial multiplexing of data streams, the mutual interference between data streams can be reduced.

[0162] Therefore, in order to implement spatial multiplexing of more data streams and improve the demodulation performance of the terminal device on the data streams, currently, the number of antenna ports corresponding to the PDSCH-DMRS can be increased by increasing the length of the frequency domain OCC sequence. Details are as follows.

[0163] Taking the PDSCH-DMRS of type 2 and occupying 2 OFDM symbols as an example, the PDSCH-DMRS can be mapped to 24 antenna ports in the manner shown in FIG. 8. That is, the network device can process the PDSCH-DMRS occupying the same frequency domain resource through a time domain OCC with a length of 2 and a frequency domain OCC with a length of 4 respectively.

[0164] Different from the manner shown in FIG. 7, in FIG. 8, the frequency domain OCCs for the 0th group (n=0) and 1st group (n=1) PDSCH-DMRS processing occupying the same frequency domain resource are OCCs with a sequence length of 4. The 0th group and 1st group PDSCH-DMRS shown in FIG. 8 also belong to one CDM group.

[0165] As shown in (a) of FIG. 8, the 0th group and 1st group PDSCH-DMRS are processed by using time domain OCC [1, 1] and frequency domain OCC [1, 1, 1, 1]; as shown in (b) of FIG. 8, the 0th group and 1st group PDSCH-DMRS are processed by using time domain OCC [1, 1] and frequency domain OCC [-1, 1, -1, 1]; as shown in (c) of FIG. 8, the 0th group and 1st group PDSCH-DMRS are processed by using time domain OCC [1, -1] and frequency domain OCC [1, 1, 1, 1]; as shown in (d) of FIG. 8, the 0th group and 1st group PDSCH-DMRS are processed by using time domain OCC [1, -1] and frequency domain OCC [-1, 1, -1, 1]; as shown in (e) of FIG. 8, the 0th group and 1st group PDSCH-DMRS are processed by using time domain OCC [1, 1] and frequency domain OCC [-1, 1, 1, 1]; as shown in (f) of FIG. 8, the 0th group and 1st group PDSCH-DMRS are processed by using time domain OCC [1, 1] and frequency domain OCC [1, -1, -1, 1]; as shown in (g) of FIG. 8, the 0th group and 1st group PDSCH-DMRS are processed by using time domain OCC [1, -1] and frequency domain OCC [-1, -1, 1, 1]; as shown in (h) of FIG. 8, the 0th group and 1st group PDSCH-DMRS are processed by using time domain OCC [1, -1] and frequency domain OCC [1, -1, -1, 1].

[0166] Thus, the PDSCH-DMRS of the 0thgroup and the 1stgroup occupying the same time-frequency domain resource can be respectively mapped to 8 different antenna ports: antenna port 0, antenna port 1, antenna port 6, antenna port 7, antenna port 12, antenna port 13, antenna port 18, and antenna port 19. Since the other REs can also be used to carry PDSCH-DMRS in addition to the PDSCH-DMRS of the 0thgroup and the 1stgroup, i.e., similar to the type 2 PDSCH-DMRS shown in FIG. 4, the other REs can also carry PDSCH-DMRS of two other CDM groups. And the PDSCH-DMRS of each CDM group of the two other CDM groups can also be respectively mapped to 8 antenna ports. For example, the PDSCH-DMRS of one of the CDM groups can be mapped to: antenna port 2, antenna port 3, antenna port 4, antenna port 5, antenna port 14, antenna port 15, antenna port 16, and antenna port 17; and the PDSCH-DMRS of the other CDM group can be mapped to: antenna port 8, antenna port 9, antenna port 10, antenna port 11, antenna port 20, antenna port 21, antenna port 22, and antenna port 23.

[0167] Thus, in the case where all the REs shown in FIG. 8 carry PDSCH-DMRS, the PDSCH-DMRS can be mapped to 24 antenna ports in total.

[0168] Similarly, when the network device processes the PDSCH-DMRS occupying the same time-frequency domain resource by using time domain OCC with a length of 2 and frequency domain OCC with a length of 4, if the PDSCH-DMRS is of the DMRS type 1 and the PDSCH-DMRS time domain resource is 2 OFDM symbols, as shown in FIG. 9, the PDSCH-DMRS includes PDSCH-DMRS of 2 CDM groups in total, and the PDSCH-DMRS of each CDM group can be mapped to 8 antenna ports, so that the PDSCH-DMRS can be mapped to 16 antenna ports in total.

[0169] However, with the development of communication technology, in a multi-user scenario, if the number of spatial division layers of a data stream is greater than 24 streams, since the current method allows the PDSCH-DMRS to be mapped to at most 24 antenna ports, the number of DMRS orthogonal ports is insufficient, thereby affecting the data demodulation performance of the terminal device and limiting the system capacity.

[0170] Therefore, the application provides a demodulation reference signal transceiving method. A network device can configure a first type of DMRS. The time domain resources of the DMRS of the first type include N sub-time domain resources. Every two sub-time domain resources in the N time domain resources carry DMRSs corresponding to different antenna ports. The N sub-time domain resources are respectively located in N time units. N is an integer greater than or equal to 2. The first type of DMRS can be used to demodulate data transmitted in the N time units. Data corresponding to the same antenna port is transmitted in the N time units.

[0171] For example, the N time units can be N time slots. Therefore, the antenna ports corresponding to the first type of DMRS transmitted in any two time slots in the N time slots are different. Assuming that the DMRS transmitted in one time slot can be mapped to W antenna ports at most, the first type of DMRS can be mapped to WxN antenna ports at most. In the existing method, the antenna ports corresponding to the DMRS transmitted in any two time slots in the resource scheduled for the terminal device are the same. Therefore, the existing DMRS can be mapped to W antenna ports at most. Therefore, the first type of DMRS can be mapped to more antenna ports. In a multi-user scenario and other scenarios where the channel changes slowly, the first type of DMRS can be used to demodulate more data streams with more spatial division numbers, which helps to improve the demodulation performance of the terminal device in a multi-user scenario.

[0172] For example, assuming that the first type of DMRS is PDSCH-DMRS and N is 2. The two time units are two time slots, and each sub-time domain resource is two OFDM symbols. In the case of PDSCH-DMRS being DMRS type 1, the first type of DMRS can be as shown in FIG. 10. The PDSCH-DMRS carried in time slot 1 and the PDSCH-DMRS carried in time slot 2 are the first type of DMRS. The first type of DMRS can be used to demodulate the PDSCH transmitted in time slot 1 and the PDSCH transmitted in time slot 2.

[0173] For example, in time slot 1, the antenna ports mapped by the PDSCH-DMRS of one CDM group are antenna port 0, antenna port 1, antenna port 4, antenna port 5, antenna port 8, antenna port 9, antenna port 12, and antenna port 13. The antenna ports mapped by the PDSCH-DMRS of the other CDM group are antenna port 2, antenna port 3, antenna port 6, antenna port 7, antenna port 10, antenna port 11, antenna port 14, and antenna port 15.

[0174] Similarly, the PDSCH-DMRS in the time slot 2 also includes two CDM groups, one CDM group of the PDSCH-DMRS is mapped to the antenna ports: antenna port 16, antenna port 17, antenna port 20, antenna port 21, antenna port 24, antenna port 25, antenna port 28 and antenna port 29; another CDM group of the PDSCH-DMRS is mapped to the antenna ports: antenna port 18, antenna port 19, antenna port 22, antenna port 23, antenna port 26, antenna port 27, antenna port 30 and antenna port 31.

[0175] Therefore, the first type of DMRS can be mapped to 32 antenna ports. Compared with the PDSCH-DMRS shown in FIG. 9, the number of the antenna ports mapped by the first type of DMRS provided in the embodiment of the application is twice the number of the antenna ports mapped by the PDSCH-DMRS shown in FIG. 9.

[0176] By analogy, as N increases, the number of the antenna ports mapped by the first type of DMRS can be more, and the number of the antenna ports mapped by the first type of DMRS can be N*16.

[0177] Exemplarily, assuming that N is 3, in combination with FIG. 10, the time slot 2 can further include a time slot 3, the PDSCH-DMRS can also be transmitted on the OFDM symbol 2 and the OFDM symbol 3 in the time slot 3, and the PDSCH-DMRS transmitted on the OFDM symbol 2 and the OFDM symbol 3 in the time slot 3 is different from the PDSCH-DMRS transmitted in the time slot 1 and different from the PDSCH-DMRS transmitted in the time slot 2. Moreover, the PDSCH-DMRS transmitted on the OFDM symbol 2 and the OFDM symbol 3 in the time slot 3 can also be mapped to 16 antenna ports. Therefore, when N is 3, the first type of DMRS can be mapped to 48 antenna ports.

[0178] It should be understood that FIG. 10 is only an example, and the indexes of the OFDM symbols occupied by the PDSCH-DMRS in the time slot 1 and the indexes of the OFDM symbols occupied by the PDSCH-DMRS in the time slot 2 can also be different, for example, the OFDM symbols occupied by the PDSCH-DMRS in the time slot 2 are the OFDM symbol 0 and the OFDM symbol 1, etc., which are not limited herein.

[0179] In addition, it should be noted that, in the case that the first type of DMRS is the PDSCH-DMRS, the first type of DMRS in the embodiment of the application is not necessarily arranged in the type 1 manner, and the first type of DMRS can also be arranged in the type 2 manner.

[0180] For example, assuming N is 2, as shown in FIG. 11, the PDSCH-DMRS transmitted in time slot 1 includes PDSCH-DMRS of 3 CDM groups, and similar to the PDSCH-DMRS of the 0th group and the 1st group shown in FIG. 8, the PDSCH-DMRS of each CDM group can be mapped to 8 antenna ports, so the PDSCH-DMRS of the three CDM groups in time slot 1 can be collectively mapped to 24 antenna ports.

[0181] For example, in time slot 1, the antenna ports to which the PDSCH-DMRS of one CDM group is mapped are: antenna port 0, antenna port 1, antenna port 6, antenna port 7, antenna port 12, antenna port 13, antenna port 18, and antenna port 19; the antenna ports to which the PDSCH-DMRS of one CDM group is mapped are: antenna port 2, antenna port 3, antenna port 8, antenna port 9, antenna port 14, antenna port 15, antenna port 20, and antenna port 21; and the antenna ports to which the PDSCH-DMRS of one CDM group is mapped are: antenna port 4, antenna port 5, antenna port 10, antenna port 11, antenna port 16, antenna port 17, antenna port 22, and antenna port 23.

[0182] Similarly, the PDSCH-DMRS of the three CDM groups in time slot 2 can also be collectively mapped to 24 antenna ports. Therefore, the first type of DMRS can be collectively mapped to 48 antenna ports. Compared with the PDSCH-DMRS shown in FIG. 8, the number of antenna ports to which the first type of DMRS provided by the embodiments of the present application is mapped is twice the number of antenna ports to which the PDSCH-DMRS shown in FIG. 8 is mapped. By analogy, as N increases, the number of antenna ports to which the first type of DMRS is mapped can be more, and the number of antenna ports to which the first type of DMRS is mapped can be N x 24.

[0183] It should be understood that FIG. 11 is only an example, and the indexes of the OFDM symbols occupied by the PDSCH-DMRS in time slot 1 and the indexes of the OFDM symbols occupied by the PDSCH-DMRS in time slot 2 can also be different, for example, the OFDM symbols occupied by the PDSCH-DMRS in time slot 2 are OFDM symbol 0 and OFDM symbol 1, etc., which are not limited in the present application.

[0184] The demodulation reference signal transmission method provided by the embodiments of the present application will be described in detail below with reference to FIGS. 12-15. The embodiments shown in the present application show the demodulation reference signal transmission method provided by the present application from the perspective of device interaction. The specific forms and quantities of the devices shown are only examples, and should not constitute any limitation on the implementation of the method provided by the present application. In the following, the network device and the terminal device are taken as the execution subject as an example to describe the demodulation reference signal transmission method of the embodiments of the present application in detail.

[0185] It should be understood that the terminal device can be a terminal device itself, a chip, a chip system or a processor supporting the terminal device to implement the method for transmitting and receiving demodulation reference signals, or a logic module or software capable of implementing all or part of the terminal device. The network device can be a network device itself, a chip, a chip system or a processor supporting the network device to implement the method for transmitting and receiving demodulation reference signals, or a logic module or software capable of implementing all or part of the network device. The present application does not make a specific limitation on this.

[0186] FIG. 12 is a flow diagram of a method 1200 for transmitting and receiving demodulation reference signals according to an embodiment of the present application. The method 1200 is applicable to the system 600. The method 1200 includes the following steps:

[0187] S1201, the terminal device acquires a first time domain resource. The first time domain resource is used for transmitting a first type of DMRS. The first time domain resource includes N sub-time domain resources. DMRSs transmitted by any two of the N sub-time domain resources correspond to different antenna ports. Any two of the N sub-time domain resources are located in different time units. N is greater than or equal to 2.

[0188] The first time domain resource can be determined by a protocol or configured by the network device through signaling. For details, refer to the description below.

[0189] S1202, the network device determines the first type of DMRS.

[0190] S1203, the network device transmits the first type of DMRS to the terminal device in the first time domain resource. Correspondingly, the terminal device receives the first type of DMRS from the network device.

[0191] The first type of DMRS can be carried in a plurality of physical channels. For example, the first type of DMRS is carried in a PDSCH, and the first type of DMRS can be a PDSCH-DMRS. Alternatively, the first type of DMRS is carried in a PDCCH, and the first type of DMRS can be a PDCCH-DMRS.

[0192] Further, assuming that the first type of DMRS is carried in a first channel, the first type of DMRS can be used to demodulate data transmitted through the first channel. For example, assuming that the first type of DMRS is a PDSCH-DMRS, the first type of DMRS can be used to demodulate data transmitted through a PDSCH.

[0193] The first type of DMRS can be used to demodulate data from the network device, data corresponding to the same antenna port in the data being transmitted within N time units in which the N sub-time domain resources are located. The data can be data carried on the PDSCH, that is, data transmitted through the PDSCH. Wherein, the data corresponding to the same antenna port in the data being transmitted within N time units in which the N sub-time domain resources are located can also be understood as the data transmitted in any two time units within the N time units corresponding to the same antenna port, for example, the data transmitted in one time unit corresponds to antenna port 1, and the data transmitted in another time unit corresponds to antenna port 1.

[0194] Exemplarily, in combination with FIG. 10, the first type of DMRS transmitted in slot 1 and the first type of DMRS transmitted in slot 2 can be used to demodulate data transmitted through the PDSCH in slot 1, and can also be used to demodulate data transmitted through the PDSCH in slot 2. Wherein, the antenna port corresponding to the data transmitted through the PDSCH in slot 1 and the antenna port corresponding to the data transmitted through the PDSCH in slot 2 are both 32 antenna ports shown in FIG. 10. In other words, the data transmitted through the PDSCH in FIG. 10 can be transmitted in slot 1 and slot 2.

[0195] It should be understood that in the embodiments of the present application, the time unit can be a slot, or can also be a subframe, a frame, or other time granularity. The present application does not make specific limitations thereto.

[0196] Wherein, the first time domain resource is a time domain resource occupied by the first type of DMRS. Each of the N sub-time domain resources is in a time unit. The time unit can be a slot, for example, and the N sub-time domain resources are in N slots, respectively. The antenna port corresponding to the DMRS can also be understood as an antenna port mapped by the DMRS, etc.

[0197] Each of the N sub-time domain resources can include one or more OFDM symbols, etc., and the number of OFDM symbols included in any two of the N sub-time domain resources can be the same or different, for example, N is 2, one sub-time domain resource includes 2 OFDM symbols, and the other sub-time domain resource can include 1 or 2 OFDM symbols, etc. In the case where each sub-time domain resource includes 2 OFDM symbols, the first type of DMRS can be as shown in FIG. 10 or FIG. 11, for example. In addition, the OFDM symbol included in each sub-time domain resource can also be less, for example, each sub-time domain resource can also include 1 OFDM symbol.

[0198] In an example, assuming the first type of DMRS is type 1 PDSCH-DMRS and N is 2, the first type of DMRS can be as shown in FIG. 13. Since in each slot, the PDSCH-DMRS occupies half of the time domain resources, compared with the PDSCH-DMRS in FIG. 10, the number of antenna ports that the PDSCH-DMRS of each CDM group is mapped to is reduced in each slot. That is, in the two CDM groups in slot 1, the PDSCH-DMRS of each CDM group is mapped to 2 antenna ports; in the two CDM groups in slot 2, the PDSCH-DMRS of each CDM group is mapped to 2 antenna ports. Therefore, the first type of DMRS is mapped to 8 antenna ports in total.

[0199] As can be seen from FIG. 13, in the case where the first type of DMRS is type 1 PDSCH-DMRS and each sub-time domain resource includes 1 OFDM symbol, if the PDSCH-DMRS of 2 CDM groups is carried in each slot, the PDSCH-DMRS in each slot can be mapped to 4 antenna ports in total. Therefore, as N increases, the first type of DMRS on N sub-time domain resources can be mapped to N x 4 antenna ports in total.

[0200] In another example, assuming the first type of DMRS is type 2 PDSCH-DMRS and N is 2, the first type of DMRS can be as shown in FIG. 14. Since in each slot, the PDSCH-DMRS occupies half of the time domain resources, compared with the PDSCH-DMRS in FIG. 11, the number of antenna ports that the PDSCH-DMRS of each CDM group is mapped to is reduced in each slot. That is, in the three CDM groups in slot 1, the PDSCH-DMRS of each CDM group is mapped to 2 antenna ports; in the three CDM groups in slot 2, the PDSCH-DMRS of each CDM group is mapped to 2 antenna ports. Therefore, the first type of DMRS is mapped to 12 antenna ports in total.

[0201] As can be seen from FIG. 14, in the case where the first type of DMRS is type 2 PDSCH-DMRS and each sub-time domain resource includes 1 OFDM symbol, if the PDSCH-DMRS of 3 CDM groups is carried in each slot, the PDSCH-DMRS in each slot can be mapped to 6 antenna ports in total. Therefore, as N increases, the first type of DMRS on N sub-time domain resources can be mapped to 6 x N antenna ports in total.

[0202] It should be further noted that FIG. 10, FIG. 11, FIG. 13 and FIG. 14 are merely examples, and the time domain mapping type of the first type of DMRS can also be mapping type B, and the starting position of each sub-time domain resource can be the first OFDM symbol of the PDSCH time domain resource. For example, the PDSCH time domain resource is OFDM symbol 8 to OFDM symbol 12 of each slot, and the first type of DMRS can occupy OFDM symbol 8 of each slot, or OFDM symbol 8 and OFDM symbol 9 of each slot, etc. For details, refer to the foregoing description, which will not be repeated here.

[0203] As can be seen, as N increases, the number of antenna ports mapped by the first type of DMRS can be more. N can be determined in the following manner.

[0204] Alternatively, N is agreed by the protocol, or N is configured by the network device through signaling.

[0205] In this way, in the case where N is agreed by the protocol, the network device does not need to indicate N to the terminal device, so that the signaling overhead is small.

[0206] Alternatively, in the case where N is configured by the network device through signaling, since as N increases, the number of antenna ports mapped by the first type of DMRS is also more, the network device can determine the value of N according to the demand, and indicate N to the terminal device. For example, in the case where the number of users is large, the value of N can be large, and in the case where the number of users is small, the value of N can be small, etc.

[0207] Exemplarily, the method 1200 further includes: the network device sends second information to the terminal device, the second information being used to indicate N. Correspondingly, the terminal device receives the second information from the network device.

[0208] Alternatively, the second information is carried in an RRC message or DCI.

[0209] The RRC message can be, for example, an RRC setup message or an RRC configuration message, etc. The second information carried in the RRC message can also be understood as the second information carried in a high layer parameter or an RRC parameter, etc. When the second information is carried in DCI, the second information can be carried in DCI 1_0 or DCI 1_1, for example.

[0210] After that, the method 1200 can further include: S1204, the network device sends data to the terminal device within N time units in which N sub-time domain resources are located, and the first type of DMRS is used to demodulate the data. Correspondingly, the terminal device receives the data from the network device. S1205, the terminal device demodulates the data transmitted within the N time units based on the first type of DMRS.

[0211] It should be understood that, assuming the first type of DMRS is PDSCH-DMRS, the data can be data transmitted through PDSCH. Alternatively, in the case that the first type of DMRS is DMRS of other channels, such as PDCCH, etc., the data is data transmitted through other channels. The present application does not make specific limitations thereto.

[0212] Optionally, the N time units can be adjacent N time units. In this way, within the N time units, the degree of channel change can be relatively small, so that the performance of the terminal device demodulating the data transmitted within the N time units based on the first type of DMRS is better.

[0213] It should be understood that in the embodiments of the present application, the N time units can be determined according to N, and the number of sub-time domain resources can be determined. N can also be referred to as DMRS window, time window or time window, etc. The present application does not make specific limitations to the name of N.

[0214] It should be noted that the terminal device demodulates the data based on the first type of DMRS, which does not limit that the first type of DMRS can only be used for demodulating data. Illustratively, the terminal device can also use the first type of DMRS for channel estimation, etc. The present application does not make specific limitations thereto.

[0215] The demodulation reference signal transmission method of the present application, the network device can configure the first type of DMRS, the time domain resource of the DMRS of this type includes N sub-time domain resources, and the N sub-time domain resources can be respectively in N time units, and the DMRS transmitted by every two sub-time domain resources in the N time domain resources corresponds to different antenna ports, N is greater than or equal to 2. In this way, with the increase of the number of N time units, the number of antenna ports mapped by the first type of DMRS can be doubled, so that the first type of DMRS can be mapped to more antenna ports. In the multi-user scenario, and in a variety of scenarios where the channel changes slowly, the first type of DMRS can be used to demodulate more data streams with spatial division number, which helps to improve the demodulation performance of the terminal device to data in the multi-user scenario.

[0216] It should be noted that the first type of DMRS can be used to demodulate data from the network device, and the data corresponding to the same antenna port is transmitted within the N time units in which the N sub-time domain resources are located. That is, for an antenna port, the first type of DMRS corresponding to the antenna port is transmitted in one of the N time units, and the data corresponding to the antenna port is transmitted within the N time units.

[0217] Exemplarily, in combination with FIG. 10, for antenna port 0, the terminal device can demodulate the data of the corresponding antenna port 0 received in time slot 1 and time slot 2 based on the first type DMRS received in time slot 1; for antenna port 16, the terminal device demodulates the data of the corresponding antenna port 16 received in time slot 1 and time slot 2 based on the first type DMRS received in time slot 2.

[0218] In addition, the network device can instruct the terminal device to activate the first type DMRS in the following manner.

[0219] As an optional embodiment, the method 1200 further includes that the network device sends first information to the terminal device, the first information being used to indicate that the first type DMRS is enabled, or the first information being used to indicate that the configured DMRS is the first type DMRS. Correspondingly, the terminal device receives the first information from the network device.

[0220] It should be understood that the activation can also be replaced by enabling, enabling, etc., which is not specifically limited in the present application.

[0221] In the case where the first information is used to indicate that the first type DMRS is enabled, the first information can also be understood as the first information being used to indicate that the state of the first switch is the open state, and the first switch can be understood as a field used to indicate whether the first type DMRS is enabled; the first information may, for example, be 1 or on, etc., indicating that the first type DMRS is enabled.

[0222] In the case where the network device instructs the terminal device not to enable the first type DMRS, the network device can not send the first information to the terminal device. That is, in the case where the network device does not send the first information to the terminal device, by default, the first type DMRS is not enabled.

[0223] Alternatively, in the case where the network device instructs the terminal device not to enable the first type DMRS, the network device can send information 1 to the terminal device, the information 1 being used to indicate that the first type DMRS is not enabled. In this case, the first information and the information 1 can be used to describe two states of the first switch, respectively. The first information can indicate that the state of the first switch is the open state, i.e., the first type DMRS is enabled; the information 1 can indicate that the state of the first switch is the closed state, i.e., the first type DMRS is not enabled. Exemplarily, the information 1 can be 0, and the first information can be 1; or the information 1 can be off, and the first information can be on, etc. In this way, the terminal device can determine whether to enable the first type DMRS according to the information 1 or the first information.

[0224] In a case that the first information is used for indicating that the configured DMRS is the first type of DMRS, the first information is information used for indicating the first type. The terminal device can determine, according to the first information, that the DMRS configured by the network device is the first type of DMRS, or it can also be understood that the terminal device can determine, according to the first information, that the DMRS received by the terminal device is the first type of DMRS.

[0225] It should be understood that in the embodiments of the present application, the first type can also be referred to as joint DMRS, multi-slot joint DMRS, type 3, type C, first pattern or first pattern, etc., and the first switch can also be referred to as multi-slot joint DMRS switch, etc., and the name of the type of DMRS is not limited in the present application.

[0226] Optionally, the first information can be carried in a high layer parameter or an RRC parameter, for example, can be carried in a time domain resource allocation list field. For example, the first information can be carried in an MIB, an SIB1 message, an RRC setup message or an RRC configuration message. Alternatively, the first information can also be carried in DCI. The present application does not make a specific limitation here.

[0227] On the basis of the above-mentioned embodiments, the terminal device can also indicate to the network device whether it has the capability of using the first type of DMRS.

[0228] As an optional embodiment, the method 1200 further comprises: the terminal device sends third information to the network device, the third information being used for indicating that the terminal device supports the first type of DMRS. Correspondingly, the network device receives the third information from the terminal device.

[0229] The third information can be carried in a UE capability information message, etc. The terminal device supporting the first type of DMRS means that the terminal device can demodulate the information transmitted through the first channel and the information transmitted through the second channel by using the first type of DMRS.

[0230] In a case that the terminal device does not support the first type of DMRS, the terminal device can not send the third information to the network device. That is, in a case that the terminal device does not send the third information to the network device, it is by default that the terminal device does not support the first type of DMRS.

[0231] Alternatively, in a case that the terminal device indicates to the network device that it does not support the first type of DMRS, the terminal device can send information 2 to the network device, the information 2 being used for indicating that the terminal device does not support the first type of DMRS.

[0232] In this case, the information 2 and the third information can be understood as information respectively used to describe two different states of a field. The field can be a field used to describe whether the terminal device supports the first type of DMRS. Exemplarily, the name of the field is, for example, UE-capability-joint DMRS or UE-capability-type 3, etc. The information 2 and the third information are respectively used to represent two states of the field, for example, the information 2 can be 0, and the third information can be 1; or the information 2 can be off, and the third information can be on, etc. So that the network device can determine whether the terminal device supports the first type of DMRS according to the information 2 or the third information. And so that the network device can configure the first type of DMRS in the case that the terminal device supports the first type of DMRS, thereby enabling the network device to not configure invalid DMRS for the terminal device, thereby enabling the communication quality between the network device and the terminal device to be higher.

[0233] Optionally, the third information can be a response to the information 3. Exemplarily, the method 900 further includes: the network device sends the information 3 to the terminal device, the information 3 being used to inquire whether the terminal device supports the first type of DMRS. Correspondingly, the terminal device receives the information 3 from the network device. And the terminal device sends the third information to the network device in response to the information 3.

[0234] Wherein, the information 3 is carried in a message such as a UE capability request (capability enqiry), for example.

[0235] In this way, the network device can send the information 3 to the terminal device before configuring the DMRS, so that the network device can determine whether the terminal device supports the first type of DMRS before configuring the DMRS.

[0236] It should be noted that in the embodiments of the present application, the number of terminal devices performing the method 1200 can be one or more. For example, the plurality of terminal devices includes a first terminal device and a second terminal device. Each terminal device in the plurality of terminal devices can receive the first type of DMRS transmitted on the part of the N sub-time domain resources. For example, in combination with FIG. 10, FIG. 11, FIG. 13 and FIG. 14, the first terminal device can receive the first type of DMRS transmitted in the time slot 1, and the second terminal device can receive the first type of DMRS transmitted in the time slot 2, etc. And the first terminal device can demodulate the data transmitted in the time slot 1 and / or the time slot 2 based on the first type of DMRS transmitted in the time slot 1; the second terminal device can demodulate the data transmitted in the time slot 1 and / or the time slot 2 based on the first type of DMRS transmitted in the time slot 2. The present application does not make a specific limitation in this regard.

[0237] In addition to the method 1200 shown above, the present application also provides another reference signal configuration method 1300. The method 1300 can be applied to the communication system 600. The method 1300 includes the following steps:

[0238] S1301, the terminal device acquires a first time domain resource. The first time domain resource is used for transmitting a first type of DMRS. The first time domain resource includes N sub-time domain resources, any two sub-time domain resources of the N sub-time domain resources transmit DMRSs corresponding to different antenna ports, the N sub-time domain resources are in one time unit, and N is greater than or equal to 2.

[0239] S1302, the network device determines the first type of DMRS.

[0240] S1303, the network device transmits the first type of DMRS to the terminal device at the first time domain resource. Correspondingly, the terminal device receives the first type of DMRS from the network device.

[0241] Optionally, the method 1300 can further include: S1304, the network device transmits data to the terminal device within N time units in which the N sub-time domain resources are located, and the first type of DMRS is used for demodulating the data. Correspondingly, the terminal device receives the data from the network device. S1305, the terminal device demodulates the data transmitted within the N time units based on the first type of DMRS, and the data corresponding to the same antenna port in the data is transmitted within the N time units.

[0242] It should be understood that the implementation of the method 1300 is similar to that of the method 1200, and the difference between the method 1300 and the method 1200 is that in the method 1300, the N sub-time domain resources are in one time unit. For example, the N sub-time domain resources can be in the first time unit of the N time units.

[0243] Exemplarily, assuming that the first type of DMRS is PDSCH-DMRS, N is 2, the two time units are two slots, and each sub-time domain resource is two OFDM symbols. In the case that the PDSCH-DMRS is DMRS type 1, the first type of DMRS can be as shown in FIG. 15. Among them, the PDSCH-DMRS in the slot 1 and the PDSCH-DMRS in the slot 2 are the first type of DMRS, which can be used to demodulate the PDSCH transmitted in the slot 1 and the PDSCH transmitted in the slot 2.

[0244] The difference between the first type of DMRS shown in FIG. 15 and the first type of DMRS shown in FIG. 10 is that the PDSCH-DMRS carried in the slot 2 in FIG. 10 is switched to the slot 1. The remaining contents are the same.

[0245] It can be seen that the first type DMRS provided in the embodiments of the present application can be mapped to more antenna ports. In a multi-user scenario and in various scenarios where the channel changes slowly, the first type DMRS can be used to demodulate more data streams with spatial division numbers, which helps to improve the demodulation performance of the terminal device on data in a multi-user scenario. By way of example, comparing FIG. 15 with FIG. 9, the first type DMRS shown in FIG. 15 is mapped to 32 antenna ports, and the PDSCH-DMRS shown in FIG. 9 is mapped to 16 antenna ports. It can be seen that the first type DMRS in the method 1300 can also be mapped to more antenna ports. In the method 1300, the terminal device can receive all the first type DMRS at an earlier position (for example, in slot 1), so that the efficiency of the terminal device in demodulating data transmitted in N time units based on the first type DMRS is higher, and the time delay of demodulating data is lower.

[0246] It should be understood that FIG. 15 is only an example, and the first time domain resource can also be another OFDM symbol in slot 1. In addition, the N sub-time domain resources can be adjacent or not adjacent, for example, in combination with FIG. 15, assuming that N is 2, the 2 sub-time domain resources can also be OFDM symbol 0 and OFDM symbol 1 in slot 1, and OFDM symbol 4 and OFDM symbol 5, etc. For the sake of brevity, they will not be shown one by one here.

[0247] It should be further noted that in the case that the first type DMRS is a type 2 PDSCH-DMRS or each sub-time domain resource is 1 OFDM symbol, the first type DMRS in the method 1300 is similar to the first type DMRS shown in FIGS. 11, 13 and 14, except that the PDSCH-DMRS carried in slot 2 in the method 1300 is moved to slot 1. For the sake of brevity, they will not be shown one by one here.

[0248] It should be understood that in the embodiments of the present application, all the antenna ports mapped by the first type DMRS can also be understood as orthogonal ports, orthogonal antenna ports or DMRS orthogonal ports, that is, all the antenna ports mapped by the first type DMRS are orthogonal to each other. The fact that all the antenna ports mapped by the first type DMRS are orthogonal to each other also means that the mutual interference between the DMRS transmitted through the respective antenna ports is small. The present application does not make a specific limitation in this regard.

[0249] It should also be understood that the size of the serial number of each method does not mean the order of execution, and the execution order of each process should be determined according to its function and inherent logic.

[0250] The demodulation reference signal transceiving method of the embodiments of the present application is described in detail above in combination with FIG. 10 to FIG. 15, and the communication apparatus of the embodiments of the present application is described in detail below in combination with FIG. 16 to FIG. 19. The communication apparatus includes modules or units for performing the corresponding parts of each of the above-described embodiments. The modules or units can be software, hardware, or a combination of software and hardware. The communication apparatus is only briefly exemplified below, and for details of the implementation scheme, reference can be made to the description of the above-described method embodiments, which will not be described herein again.

[0251] FIG. 16 is a schematic block diagram of a communication apparatus 1600 provided by an embodiment of the present application. As shown in FIG. 16, the communication apparatus 1600 includes a processing module 1601 and a transceiving module 1602.

[0252] In a possible implementation, the communication apparatus 1600 is configured to implement the steps corresponding to the terminal device in the above-described method 1200 or method 1300.

[0253] The processing module 1601 is configured to: obtain a first time domain resource, the first time domain resource being used for transmission of a first type of demodulation reference signal (DMRS), the first time domain resource including N sub-time domain resources, any two of the N sub-time domain resources being different in time unit, and any two of the N sub-time domain resources being different in antenna port, N being greater than or equal to 2; and the transceiving module 1602 is configured to: receive the first type of DMRS from a network device on the first time domain resource, the first type of DMRS being used for demodulation of data from the network device, data corresponding to a same antenna port in the data being transmitted within N time units in which the N sub-time domain resources are located.

[0254] Optionally, the transceiving module 1602 is further configured to: receive first information from the network device, the first information being used for indicating activation of the first type of DMRS or indicating that the received DMRS is the first type of DMRS.

[0255] Optionally, the transceiving module 1602 is further configured to: receive second information from the network device, the second information being used for indicating N.

[0256] Optionally, the second information is carried in a radio resource control (RRC) message or downlink control information (DCI).

[0257] Optionally, the transceiving module 1602 is further configured to: send third information to the network device, the third information being used for indicating that the communication apparatus 1600 supports the first type of DMRS.

[0258] Optionally, the third information is carried in an RRC message or DCI.

[0259] In a possible implementation, the communication apparatus 1600 is configured to implement the steps corresponding to the network device in the method 1200 or the method 1300.

[0260] The processing module 1601 is configured to determine a first type of demodulation reference signal (DMRS), and the transceiver module 1602 is configured to transmit the first type of DMRS to the terminal device on a first time domain resource, the first time domain resource including N sub-time domain resources, the first type of DMRS transmitted on any two of the N sub-time domain resources corresponding to different antenna ports, any two of the N sub-time domain resources being located in different time units, N being greater than or equal to 2, the first type of DMRS being used for demodulating data transmitted to the terminal device, data corresponding to a same antenna port in the data being transmitted within N time units in which the N sub-time domain resources are located.

[0261] Optionally, the transceiver module 1602 is further configured to transmit first information to the terminal device, the first information being used to indicate that the first type of DMRS is activated or to indicate that a configured DMRS is the first type of DMRS.

[0262] Optionally, the transceiver module 1602 is further configured to transmit second information to the terminal device, the second information being used to indicate N.

[0263] Optionally, the second information is carried in a radio resource control (RRC) message or downlink control information (DCI).

[0264] Optionally, the transceiver module 1602 is further configured to receive third information from the terminal device, the third information being used to indicate that the terminal device supports the first type of DMRS.

[0265] Optionally, the third information is carried in an RRC message or DCI.

[0266] It should be understood that the communication apparatus 1600 is embodied in the form of functional modules herein. The term “module” herein can refer to an application specific integrated circuit (ASIC), an electronic circuit, a processor (for example, a shared processor, a dedicated processor, or a group processor and the like) and a memory for executing one or more software or firmware programs, a combinational logic circuit, and / or other suitable components that support the described functions. In an optional example, those skilled in the art can understand that the communication apparatus 1600 can be embodied as the terminal device or the network device in the above-described embodiments, and the apparatus 1600 can be configured to execute the respective processes and / or steps corresponding to the terminal device or the network device in the above-described method embodiments. To avoid repetition, details are not described herein.

[0267] The apparatus 1600 described above has a function of implementing the corresponding steps performed by the terminal device or the network device in the above method; the above function can be implemented by hardware, or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above functions. In the embodiment of the present application, the communication apparatus 1600 in FIG. 16 can also be a chip, for example: SOC.

[0268] FIG. 17 shows a structural schematic diagram of a communication apparatus 1700 provided by an embodiment of the present application. The communication apparatus 1700 includes a processor 1701, a transceiver 1702, and a memory 1703. The processor 1701, the transceiver 1702, and the memory 1703 communicate with each other through an internal connection path. The memory 1703 is used to store instructions, such as computer degree codes, etc. The processor 1701 is used to execute the instructions stored in the memory 1703 to control the transceiver 1702 to transmit and / or receive signals.

[0269] It should be understood that the communication apparatus 1700 can be specifically the network device or the terminal device in the above embodiments, and can be used to execute the respective steps and / or processes corresponding to the network device or the terminal device in the above method embodiments. Optionally, the memory 1703 can include a read-only memory and a random access memory, and provide instructions and data for the processor. A part of the memory can also include a non-volatile random access memory. For example, the memory can also store device type information. The processor 1701 can be used to execute the instructions stored in the memory, and when the processor 1701 executes the instructions stored in the memory, the processor 1701 is used to execute the respective steps and / or processes of the above method embodiments. The transceiver 1702 can include a transmitter 17021, a receiver 17022, and an antenna 17023. The transmitter 17021 can be used to implement the respective steps and / or processes corresponding to the above transceiver for executing the transmitting action. For example, the transmitter 17021 can be used to transmit information to another device through the antenna 17023. The receiver 17022 can be used to implement the respective steps and / or processes corresponding to the above transceiver for executing the receiving action. For example, the receiver 17022 can be used to receive information from another device through the antenna 17023.

[0270] It should be understood that in the embodiments of the present application, the processor can be a central processing unit (CPU), and the processor can also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field programmable gate arrays (FPGAs) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor.

[0271] In the implementation process, each step of the above method can be completed by integrated logic circuit of hardware in the processor or instruction in the form of software. The steps of the method disclosed in combination with the embodiments of the present application can be directly embodied as hardware processor execution completion, or executed by hardware and software module combination in the processor. The software module can be located in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, register, and other mature storage media in the art. The storage medium is located in the memory, and the processor executes the instruction in the memory to complete the steps of the above method in combination with the hardware. To avoid repetition, it will not be described in detail here.

[0272] FIG. 18 is a schematic diagram of an O-RAN system according to an embodiment of the present application. The O-RAN system can also include other components in addition to the components shown in FIG. 18.

[0273] As shown in FIG. 18, the network device in the embodiment of the present application can also be referred to as an access network device. The access network device (i.e., RAN, which can be eNB or gNB or next-generation access network device) can communicate with the core network (CN) through a backhaul link, and can also communicate with the terminal device through an air interface.

[0274] Specifically, the baseband unit (BBU) in the access network device can communicate with the core network device through a backhaul link; the radio unit (RU) in the access network device can communicate with at least one terminal device through an air interface. The BBU can communicate with at least one RU through a front-haul link, and the BBU and the RU can be co-located or not co-located.

[0275] The BBU includes at least one control unit (CU) and at least one distributed unit (DU), which can communicate through at least one midhaul link.

[0276] FIG. 19 is a network element function division and protocol layer structure diagram of an O-RAN device according to an embodiment of the present application.

[0277] In some examples, the CU is a logical node that carries radio resource control (RRC) layer, service data adaptation protocol (SDAP) layer, packet data convergence protocol (PDCP) layer, and other control functions of the access network device. The CU is connected to network nodes such as core network devices through some interfaces, which can be E2 interface, etc. Optionally, the CU can have part of the functions of the core network device. The CU (e.g., PDCP layer and higher layers) is connected to the DU (e.g., RLC layer and lower layers) through some interfaces, which can be F1 interface, etc. In some examples, these interfaces (e.g., F1 interface) can provide control plane (C-Plane) and user plane (U-Plane) functions, such as interface management, system information management, UE context management, and RRC message transmission, etc. F1AP is an application protocol of F1 interface, which defines signaling procedures of F1 in some examples. The F1 interface supports control plane F1-C and user plane F1-U.

[0278] In some examples, the CU can be split into a CU-CP (control unit-control plane) and a CU-UP (control unit-user plane), where the CU-CP is a logical node carrying the RRC layer and the PDCP-C (control plane part of PDCP) layer, used to implement the control plane function of the CU. The CU-CP can interact with a network element in the core network used to implement the control plane function. The network element in the core network used to implement the control plane function can be an access and mobility function network element, such as an access and mobility management function (AMF) in a 5G system. The AMF network element is used to be responsible for mobility management in a mobile network, such as location updating of a terminal device, registration of the terminal device to a network, handover of the terminal device, and the like. The CU-UP is a logical node carrying the SDAP layer and the PDCP-U (user plane part of PDCP) layer, used to implement the user plane function of the CU. The CU-UP can interact with a network element in the core network used to implement the user plane function. The network element in the core network used to implement the user plane function, for example, a user plane function (UPF) in a 5G system, is used to be responsible for forwarding and receiving data in a terminal device. The above configuration of the CU and the DU is merely an example, and the CU and the DU can have functions according to needs. For example, the CU or the DU can be configured to have more protocol layer functions, or the CU or the DU can be configured to have partial processing functions of the protocol layer. For example, part of the functions of the RLC layer and the functions of the protocol layer above the RLC layer are arranged in the CU, and the remaining functions of the RLC layer and the functions of the protocol layer below the RLC layer are arranged in the DU. For another example, the functions of the CU or the DU can be divided according to the service type or other system requirements, for example, according to the delay. The functions that need to meet the delay requirement are arranged in the DU, and the functions that do not need to meet the delay requirement are arranged in the CU.

[0279] In some examples, a DU is a logical node that hosts radio link control (RLC) layer, medium access control (MAC) layer, higher physical layer (higher PHY) layer, and other functions. In some examples, a DU can control at least one RU. The DU is connected with the RUs through some interfaces, which can be a fronthaul interface. In some examples, the higher PHY layer includes parts of PHY layer processing, such as forward error correction (FEC) encoding and decoding, scrambling, modulation and demodulation, and other processing functions.

[0280] In some examples, an RU is a logical node that hosts lower physical layer (lower PHY) and radio frequency (RF) processing, which can also be referred to as radio frequency chain (RF chain). In some examples, an RU can be a 3GPP transmission reception point (TRP) or a remote radio head (RRH) or other similar functional entity. In some examples, the low-PHY includes parts of PHY processing, such as fast Fourier transform (FFT), inverse fast fourier transformation (IFFT), digital beamforming and filtering, and other processing functions. The RU communicates with one or more UEs through a wireless link.

[0281] The DU and the RU can be co-located or not co-located. The DU and the RU exchange control plane information and user plane information through a lower-layer split CUS-plane (LLS-CUS) interface via a lower-layer split-control, user and synchronization (LLS-CUS) interface. The LLS-CUS can include a LLS-C interface and a LLS-U interface that provide control plane (C-plane) and user plane (U-plane), respectively. In some examples, the control plane (C-plane) refers to real-time control between the DU and the RU. The DU and the RU exchange management information through a LLS-M interface of the lower-layer split link, and the management plane (M-plane) refers to non-real-time management operations between the DU and the RU.

[0282] The DU and the RU can cooperate to jointly implement the functions of the PHY layer. One DU can be connected with one or more RUs. The functions of the DU and the RU can be configured in various ways according to design. For example, the DU is configured to implement baseband functions, and the RU is configured to implement radio frequency functions. For another example, the DU is configured to implement high-layer functions in the PHY layer, and the RU is configured to implement low-layer functions in the PHY layer or implement the low-layer functions and radio frequency functions. The high-layer functions in the PHY layer can include a part of functions of the PHY layer that are closer to the MAC layer, and the low-layer functions in the PHY layer can include another part of functions of the PHY layer that are closer to the radio frequency side.

[0283] In different systems, the CU (or CU-CP and CU-UP), the DU, or the RU can also have different names, but those skilled in the art can understand their meanings. For example, in an ORAN system, the CU can also be referred to as an O-CU (open CU), the DU can also be referred to as an O-DU, the CU-CP can also be referred to as an O-CU-CP, the CU-UP can also be referred to as an O-CU-UP, and the RU can also be referred to as an O-RU. For the convenience of description, the CU, the CU-CP, the CU-UP, the DU, and the RU are taken as examples for description in this application.

[0284] The application also provides a computer-readable storage medium for storing a computer program for implementing the method shown in the above method embodiments.

[0285] The application also provides a computer program product including a computer program (also referred to as code or instructions), which, when running on a computer, can execute the method shown in the above method embodiments.

[0286] Those of ordinary skill in the art can realize that the modules and algorithm steps of each example described in combination with the embodiments disclosed herein can be realized by electronic hardware or a combination of computer software and electronic hardware. Whether the functions are executed in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the application.

[0287] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described system, device, and module can refer to the corresponding processes in the foregoing method embodiments, which will not be described here.

[0288] In several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other manners. For example, the described device embodiments are merely schematic. For example, the division of the modules is merely logical function division. There can be another division manner for the actual implementation, for example, multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections can be indirect couplings or communication connections through some interfaces, devices or modules, and can be in electrical, mechanical or other forms.

[0289] The modules illustrated as separated components can or can not be physically separated, and the components illustrated as modules can or can not be physical modules, i.e., can be located in one place, or can be distributed to multiple network modules. Some or all of the modules can be selected according to actual needs to achieve the purpose of the embodiment.

[0290] In addition, the functional modules in each embodiment of the present application can be integrated into a processing module, or each module can be physically present alone, or two or more modules can be integrated into one module.

[0291] If the functions are realized in the form of software function modules and sold or used as independent products, they can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application can be embodied in the form of a software product in essence or the part of the technical solutions that make contributions to the prior art, or part of the technical solutions. The computer software product is stored in a storage medium, and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various media that can store program codes.

[0292] The above description is merely a specific implementation of the present application, but the protection scope of the embodiments of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the embodiments of the present application, which should be covered within the protection scope of the embodiments of the present application. Therefore, the protection scope of the embodiments of the present application should be subject to the protection scope of the claims.

Claims

A demodulation reference signal receiving method, characterized in that, The method comprises: obtaining a first time domain resource, the first time domain resource being used for receiving a first type of demodulation reference signal (DMRS), the first time domain resource comprising N sub-time domain resources, any two of the N sub-time domain resources being different in an antenna port corresponding to the first type of DMRS received by the any two of the N sub-time domain resources, any two of the N sub-time domain resources being different in a time unit in which the any two of the N sub-time domain resources are located, N being an integer greater than or equal to 2; receiving, from a network device, the first type of DMRS on the first time domain resource, the first type of DMRS being used for demodulating data from the network device, data corresponding to a same antenna port in the data being transmitted within N time units in which the N sub-time domain resources are located. The method of claim 1, wherein The method further comprises: receiving, from the network device, first information, the first information being used for indicating that the first type of DMRS is activated or indicating that a received DMRS is the first type of DMRS. The method according to claim 1 or 2, characterized in that The method further comprises: receiving, from the network device, second information, the second information being used for indicating the N. The method according to claim 3, characterized in that The second information is carried in a radio resource control (RRC) message or downlink control information (DCI). The method according to any one of claims 1 to 4, characterized in that The method further comprises: sending, to the network device, third information, the third information being used for indicating that a terminal device supports the first type of DMRS. The method according to claim 5, characterized in that The third information is carried in user equipment (UE) capability information. The method according to any one of claims 1 to 6, characterized in that The data is data carried by a physical downlink shared channel (PDSCH). A demodulation reference signal transmission method characterized by comprising: The method comprises: determining a first type of demodulation reference signal (DMRS); sending, to a terminal device, the first type of DMRS on a first time domain resource, the first time domain resource comprising N sub-time domain resources, any two of the N sub-time domain resources being different in an antenna port corresponding to the first type of DMRS sent by the any two of the N sub-time domain resources, any two of the N sub-time domain resources being different in a time unit in which the any two of the N sub-time domain resources are located, the first type of DMRS being used for demodulating data sent to the terminal device, data corresponding to a same antenna port in the data being sent within N time units in which the N sub-time domain resources are located, N being an integer greater than or equal to 2. The method of claim 8, wherein The method further comprises: sending, to the terminal device, first information, the first information being used for indicating that the first type of DMRS is activated or indicating that a configured DMRS is the first type of DMRS. The method according to claim 8 or 9, characterized in that The method further comprises: sending, to the terminal device, second information, the second information being used for indicating the N. The method of claim 10, wherein The second information is carried in a radio resource control (RRC) message or downlink control information (DCI). The method according to any one of claims 8 to 11, characterized in that The method further comprises: receiving, from the terminal device, third information, the third information being used for indicating that the terminal device supports the first type of DMRS. The method of claim 12, wherein The third information is carried in user equipment (UE) capability information. The method according to any one of claims 8 to 13, characterized in that The data is data carried by a physical downlink shared channel (PDSCH). A communication device characterized by comprising: The method comprises: including a module for performing the method of any one of claims 1 to 7, or the method of any one of claims 8 to 14. A communication device characterized by comprising: The method comprises: A processor coupled with a memory for storing a computer program which, when invoked by the processor, causes the apparatus to perform the method of any one of claims 1 to 7, or the method of any one of claims 8 to 14. A computer-readable storage medium, characterized by A computer program product comprising instructions for implementing the method of any one of claims 1 to 7, or the method of any one of claims 8 to 14. A computer program product comprising instructions therein, characterized in that A computer program product comprising instructions for implementing the method of any one of claims 1 to 7, or the method of any one of claims 8 to 14.

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