Method and apparatus for data transmission

Abstract

The present application provides a method and apparatus for data transmission, which can determine the TCI-state used for data transmission and correctly receive downlink data, thereby improving the efficiency of data transmission. The method includes: receiving a first physical downlink control channel PDCCH, where the first PDCCH is used to schedule a first physical downlink shared channel PDSCH; receiving a downlink signal using a first transmission configuration indication state TCI-state; obtaining a time interval between the first PDCCH and the first PDSCH; and if the time interval is less than a preset threshold value, obtaining the first PDSCH from the downlink signal.

Description

[0001] This application claims the priority of an international patent application with the application number PCT / CN2019 / 109608, titled "Method and Device for Data Transmission", filed with the Chinese Receiving Office on September 30, 2019, the entire content of which is incorporated herein by reference. Technical Field

[0002] This application relates to the field of communications, and in particular, to a method and device for data transmission in the field of communications. Background Art

[0003] The fifth-generation (5G) mobile communication system uses high-frequency communication, that is, uses signals in the ultra-high frequency band (>6 GHz) to transmit data. A major problem with high-frequency communication is that the signal energy drops sharply as the transmission distance increases, resulting in a short signal transmission distance. To overcome this problem, high-frequency communication uses analog beamforming technology, which is processed through a large-scale antenna array to concentrate the signal energy in a smaller range, forming a signal similar to a light beam, called an analog beam (abbreviated as beam), thereby expanding the transmission distance.

[0004] The network device can generate different beams and direct them to different transmission directions. In downlink data transmission, the network device will use a specific beam to send data to the terminal device and inform the terminal device of the transmission beam information it uses, so that the terminal device can use the correct receiving beam (that is, the receiving beam corresponding to the sending beam) to receive the data sent by the network device. Exemplarily, the above-mentioned transmission beam information can be indicated by the transmission configuration indication (TCI) field in the downlink control information (DCI). Each value of the TCI field corresponds to a transmission configuration indicator state (TCI-state) index, which is used to uniquely identify a TCI-state. The TCI-state is used to determine the transmission beam information for data transmission. Therefore, determining the transmission beam information for data transmission can also be equivalently expressed as determining the TCI-state for data transmission. How the terminal device determines the TCI-state used for data transmission and uses the determined TCI-state to receive downlink data is an urgent problem to be solved. Summary of the Invention

[0005] This application provides a method and device for data transmission, which can determine the TCI-state used for data transmission and correctly receive downlink data, thereby improving the efficiency of data transmission.

[0006] In a first aspect, a data transmission method is provided, including: receiving a first physical downlink control channel (PDCCH), where the first PDCCH is used to schedule a first physical downlink shared channel (PDSCH); receiving a downlink signal using a first transmission configuration indication state (TCI-state); obtaining a time interval between the first PDCCH and the first PDSCH; and if the time interval is less than a preset threshold, obtaining the first PDSCH from the downlink signal.

[0007] In the data transmission method according to the embodiments of the present application, the terminal device can determine the TCI-state used by the network device for data transmission in various ways, so that the terminal device determines the receiving beam according to the TCI-state and receives the data sent by the network device, thereby improving the data transmission efficiency.

[0008] In combination with the first aspect, in some implementation manners of the first aspect, the first TCI-state is the TCI-state included in the TCI-state group with the smallest or largest corresponding TCI field value among one or more TCI-state groups including a TCI-state used by the first PDCCH; where the TCI-state group corresponds to a TCI field value, and the TCI-state group includes one TCI-state or two TCI-states.

[0009] In other words, there may be one TCI-state group including a TCI-state used by the first PDCCH, or there may be multiple TCI-state groups including a TCI-state used by the first PDCCH. If there is one TCI-state group including the TCI-state used by the first PDCCH, the first TCI-state is the TCI-state included in this TCI-state group. If there are multiple TCI-state groups including the TCI-state used by the first PDCCH, the first TCI-state is the TCI-state included in the TCI-state group with the smallest or largest corresponding TCI field value among these multiple TCI-state groups.

[0010] Exemplarily, the terminal device may adopt one TCI-state used by the first PDCCH as one of the first TCI-states. Then, the terminal device determines all TCI-state groups containing the above-mentioned one of the first TCI-states from at least one activated TCI-state group for PDSCH transmission (each TCI-state group corresponds to a TCI field value of the TCI field in the DCI). Finally, the terminal device selects one TCI-state group from these TCI-state groups (for example, the TCI-state group corresponding to the smallest or largest TCI field value), and uses all the TCI-states included in this TCI-state group as the first TCI-states for the terminal device to receive the downlink signal. If the TCI-state group determined by the terminal device contains one TCI-state, then the first TCI-state is one TCI-state, that is, the terminal device uses one first TCI-state to receive the downlink signal; if the TCI-state group determined by the terminal device contains two TCI-states, then the first TCI-state is two TCI-states, that is, the terminal device uses two first TCI-states to receive the downlink signal.

[0011] In combination with the first aspect, in some implementation manners of the first aspect, the first TCI-state is the TCI-state included in the TCI-state group corresponding to the smallest or largest TCI field value among one or more TCI-state groups that contain one TCI-state used by the first PDCCH and contain two TCI-states.

[0012] In other words, there may be one TCI-state group containing two TCI-states that contains one TCI-state used by the first PDCCH, or there may be multiple TCI-state groups containing two TCI-states that contain one TCI-state used by the first PDCCH. If there is one TCI-state group containing two TCI-states that contains the first PDCCH's one TCI-state, then the first TCI-state is the TCI-state included in this TCI-state group. If there are multiple TCI-state groups containing two TCI-states that contain the first PDCCH's one TCI-state, then the first TCI-state is the TCI-state included in the TCI-state group corresponding to the smallest or largest TCI field value among these multiple TCI-state groups.

[0013] In combination with the first aspect, in some implementations of the first aspect, if there is no one or more TCI-state groups that include a TCI-state used by the first PDCCH, then the first TCI-state is a TCI-state used by the first PDCCH.

[0014] The embodiments of the present application provide a fallback mechanism, such that when the terminal device cannot find a TCI-state group that can meet the requirements, a TCI-state can be used as the only first TCI-state.

[0015] In combination with the first aspect, in some implementations of the first aspect, in the case where no activation signaling is received, the first TCI-state is a TCI-state used by the first PDCCH.

[0016] In combination with the first aspect, in some implementations of the first aspect, the first TCI-state is a TCI-state included in a TCI-state group corresponding to the smallest or largest TCI field value among one or more TCI-state groups that include a TCI-state activated by the CORESET with the smallest or largest index in one or more recently received control resource sets (CORESET); wherein, the TCI-state group corresponds to a TCI field value, and the TCI-state group includes one TCI-state or two TCI-states.

[0017] In other words, one CORESET (e.g., the CORESET with the smallest or largest index) among the one or more recently received CORESETs (such as the ones received in the most recent time slot) can also be referred to as the "target CORESET". The recently received CORESET may be one or multiple. If the terminal device recently received one CORESET, the target CORESET is this one CORESET. If the terminal device recently received multiple CORESETs, the target CORESET can be the CORESET with the smallest or largest index among these multiple CORESETs. There may be one TCI-state group that contains one TCI-state activated by the target CORESET, or there may be multiple TCI-state groups that contain one TCI-state activated by the target CORESET. If there is one TCI-state group that contains one TCI-state activated by the target CORESET, the first TCI-state is the TCI-state contained in this TCI-state group. If there are multiple TCI-state groups that contain one TCI-state activated by the target CORESET, the first TCI-state is the TCI-state contained in the TCI-state group with the smallest or largest corresponding TCI field value among these multiple TCI-state groups.

[0018] In combination with the first aspect, in some implementations of the first aspect, the first TCI-state is the TCI-state contained in the TCI-state group with the smallest or largest corresponding TCI field value among the one or more TCI-state groups that contain one TCI-state activated by the CORESET with the smallest or largest index among the one or more recently received CORESETs and that contain two TCI-states.

[0019] In other words, there may be a TCI-state group containing two TCI-states that contains a TCI-state activated by the target CORESET, or there may be multiple TCI-state groups containing two TCI-states that contain a TCI-state activated by the target CORESET. If there is a TCI-state group containing two TCI-states that contains a TCI-state activated by the target CORESET, then the first TCI-state is the TCI-state contained in this TCI-state group. If there are multiple TCI-state groups containing two TCI-states that contain a TCI-state activated by the target CORESET, then the first TCI-state is the TCI-state contained in the TCI-state group with the smallest or largest corresponding TCI field value among these multiple TCI-state groups containing two TCI-states.

[0020] In combination with the first aspect, in some implementation manners of the first aspect, if there are no one or more TCI-state groups that contain a TCI-state activated by the CORESET with the smallest or largest index among the one or more recently received CORESETs, then the first TCI-state is the TCI-state activated by the CORESET with the smallest or largest index among the one or more recently received CORESETs.

[0021] In combination with the first aspect, in some implementation manners of the first aspect, in the case where no activation signaling is received, the first TCI-state is the TCI-state activated by the CORESET with the smallest or largest index among the one or more recently received CORESETs; wherein, the activation signaling is used to activate the TCI-state for PDSCH transmission.

[0022] In combination with the first aspect, in some implementations of the first aspect, the first TCI-state is the two TCI-states used for the most recent transmission of the second PDSCH, where the second PDSCH is transmitted using two TCI-states; alternatively, the first TCI-state is the TCI-state in the TCI-state group with the smallest or largest corresponding TCI field value among multiple TCI-state groups for PDSCH transmission, and the TCI-state group includes two TCI-states; alternatively, the first TCI-state is the two TCI-states used for transmitting the first PDCCH; alternatively, the first TCI-state is the two currently active TCI-states in the CORESET with the smallest or largest index among one or more control resource sets CORESET received in the most recent time slot.

[0023] Optionally, the time interval between the second PDSCH and the PDCCH scheduling the second PDSCH is not less than the preset threshold value. For example, before this transmission, the network device has performed one or more PDSCH transmissions to this terminal device. Among them, some PDSCHs are transmitted using a single TCI-state, and some PDSCHs are transmitted using two TCI-states. Among the PDSCHs transmitted using two TCI-states, some PDSCHs have a scheduling time interval less than the preset threshold value, and some PDSCHs have a scheduling time interval not less than the preset threshold value. Then, the terminal device can use the TCI-state used for the PDSCH that was most recently transmitted using two TCI-states and has a scheduling time interval not less than the preset threshold value to receive and cache the signal.

[0024] In combination with the first aspect, in some implementations of the first aspect, the first TCI-state is the TCI-state in the TCI-state group with the smallest or largest corresponding TCI field value among multiple TCI-state groups for PDSCH transmission, and the TCI-state group includes two TCI-states.

[0025] In combination with the first aspect, in some implementations of the first aspect, the first TCI-state is the two TCI-states used for transmitting the first PDCCH.

[0026] In combination with the first aspect, in some implementations of the first aspect, the first TCI-state is one of the two currently active TCI-states in a CORESET (e.g., the CORESET with the smallest or largest index) among one or more CORESETs received most recently (e.g., in the most recent time slot).

[0027] In combination with the first aspect, in some implementations of the first aspect, after determining two first TCI-states by using the above method, the terminal device can determine whether to fallback to a transmission mode using a single first TCI-state according to whether the two first TCI-states can be received simultaneously. For example, after the terminal device determines two first TCI-states and finds that the two first TCI-states cannot be received simultaneously by it, then the terminal device can use a single first TCI-state. Optionally, the single first TCI-state can be one of the above two first TCI-states, or the other first TCI-state. Optionally, the single first TCI-state can also be a TCI-state activated in the CORESET with the smallest or largest index among one or more CORESETs received most recently (e.g., received in the most recent time slot). Optionally, the single first TCI-state can also be the TCI-state used by the first PDCCH.

[0028] It should be understood that the above "the two first TCI-states cannot be received simultaneously" means that the receiving beams corresponding to the two first TCI-states are different, and the terminal device has only one antenna panel or only one antenna panel is enabled. Therefore, the terminal device cannot generate two different receiving beams simultaneously for reception.

[0029] In combination with the first aspect, in some implementations of the first aspect, the method further includes: if the time interval is greater than or equal to a preset threshold and the first PDCCH does not carry TCI-state information, determining a second TCI-state and receiving the first PDSCH by using the second TCI-state.

[0030] If the first PDCCH carries TCI-state information, for example, the DCI type carried by the first PDCCH is DCI format 1_1, and the parameter tci-PresentInDci in the CORESET corresponding to the first PDCCH is configured as "enabled". At this time, the terminal device can use the two TCI-states indicated by the TCI-state information in the DCI as the two second TCI-states for transmitting the first PDSCH.

[0031] If the first PDCCH does not carry TCI-state information, for example, the DCI type carried by the first PDCCH is DCI format 1_0, or the parameter tci-PresentInDci is not configured in the CORESET corresponding to the first PDCCH. At this time, there is no TCI field in the DCI and no TCI-state information can be indicated. The terminal device can use any one of the following methods to determine the second TCI-state.

[0032] Combined with the first aspect, in some implementation manners of the first aspect, the second TCI-state is the TCI-state included in the TCI-state group corresponding to the smallest or largest TCI field value among one or more TCI-state groups including one TCI-state used by the first PDCCH; where the TCI-state group corresponds to a TCI field value, and the TCI-state group includes one TCI-state or two TCI-states.

[0033] In other words, there may be one TCI-state group including one TCI-state used by the first PDCCH, or there may be multiple TCI-state groups including one TCI-state used by the first PDCCH. If there is one TCI-state group including the one TCI-state used by the first PDCCH, the second TCI-state is the TCI-state included in this TCI-state group. If there are multiple TCI-state groups including the one TCI-state used by the first PDCCH, the second TCI-state is the TCI-state included in the TCI-state group corresponding to the smallest or largest TCI field value among these multiple TCI-state groups.

[0034] Exemplarily, the terminal device may adopt one of the TCI-states used by the first PDCCH as one of the second TCI-states. Then, the terminal device determines all the TCI-state groups that contain the above-mentioned one of the second TCI-states from at least one activated TCI-state group for PDSCH transmission (each TCI-state group corresponds to a TCI field value of the TCI field in the DCI). Finally, the terminal device selects one TCI-state group from these TCI-state groups (for example, the TCI-state group corresponding to the smallest or largest TCI field value), and uses all the TCI-states included in this TCI-state group as the second TCI-states for the terminal device to receive the downlink signal. If the TCI-state group determined by the terminal device contains one TCI-state, then the second TCI-state is one TCI-state, that is, the terminal device uses one second TCI-state to receive the downlink signal; if the TCI-state group determined by the terminal device contains two TCI-states, then the second TCI-state is two TCI-states, that is, the terminal device uses two second TCI-states to receive the downlink signal.

[0035] In combination with the first aspect, in some implementation manners of the first aspect, the second TCI-state is the TCI-state included in the TCI-state group corresponding to the smallest or largest TCI field value among one or more TCI-state groups that contain one TCI-state used by the first PDCCH and contain two TCI-states.

[0036] In other words, there may be one TCI-state group that contains two TCI-states and contains one TCI-state used by the first PDCCH, or there may be multiple TCI-state groups that contain two TCI-states and contain one TCI-state used by the first PDCCH. If there is one TCI-state group that contains two TCI-states and contains the first PDCCH's one TCI-state, then the second TCI-state is the TCI-state included in this TCI-state group. If there are multiple TCI-state groups that contain two TCI-states and contain the first PDCCH's one TCI-state, then the second TCI-state is the TCI-state included in the TCI-state group corresponding to the smallest or largest TCI field value among these multiple TCI-state groups that contain two TCI-states.

[0037] In combination with the first aspect, in certain implementations of the first aspect, if there is no TCI-state group including one or more TCI-states used by the first PDCCH, the second TCI-state is one of the TCI-states used by the first PDCCH.

[0038] The embodiments of the present application provide a fallback mechanism, so that when the terminal device cannot find a TCI-state group that can meet the requirements, a TCI-state can be used as the only second TCI-state.

[0039] In combination with the first aspect, in certain implementations of the first aspect, in the case where no activation signaling is received, the second TCI-state is one of the TCI-states used by the first PDCCH.

[0040] In combination with the first aspect, in certain implementations of the first aspect, the second TCI-state is a TCI-state included in a TCI-state group corresponding to the smallest or largest TCI field value among one or more TCI-state groups including a TCI-state activated by the CORESET with the smallest or largest index among the one or more recently received CORESETs; wherein, the TCI-state group corresponds to a TCI field value, and the TCI-state group includes one TCI-state or two TCI-states.

[0041] One of the one or more recently received (such as received in the most recent time slot) CORESETs (for example, the CORESET with the smallest or largest index) can also be referred to as the "target CORESET". The recently received CORESET may be one or multiple. If one CORESET is recently received, the target CORESET is this one CORESET. If multiple CORESETs are recently received, the target CORESET can be the CORESET with the smallest or largest index among the multiple CORESETs.

[0042] In other words, there may be a group of TCI-states that includes a TCI-state activated by the target CORESET, or there may be multiple groups of TCI-states that include a TCI-state activated by the target CORESET. If there is a group of TCI-states that includes a TCI-state activated by the target CORESET, then the second TCI-state is the TCI-state included in this group of TCI-states. If there are multiple groups of TCI-states that include a TCI-state activated by the target CORESET, then the second TCI-state is the TCI-state included in the group of TCI-states with the smallest or largest corresponding TCI field value among these multiple groups of TCI-states.

[0043] Combined with the first aspect, in some implementation manners of the first aspect, the second TCI-state is the TCI-state included in the group of TCI-states with the smallest or largest corresponding TCI field value among one or more groups of TCI-states that include a TCI-state activated by the CORESET with the smallest or largest index among the one or more recently received CORESETs and include two TCI-states.

[0044] In other words, there may be a group of TCI-states that includes two TCI-states and includes a TCI-state activated by the target CORESET, or there may be multiple groups of TCI-states that include two TCI-states and include a TCI-state activated by the target CORESET. If there is a group of TCI-states that includes two TCI-states and includes a TCI-state activated by the target CORESET, then the second TCI-state is the TCI-state included in this group of TCI-states. If there are multiple groups of TCI-states that include two TCI-states and include a TCI-state activated by the target CORESET, then the second TCI-state is the TCI-state included in the group of TCI-states with the smallest or largest corresponding TCI field value among these multiple groups of TCI-states that include two TCI-states.

[0045] In combination with the first aspect, in some implementations of the first aspect, if there is no one or more TCI-state groups including a TCI-state activated by the CORESET with the smallest or largest index among the most recently received one or more CORESETs, the second TCI-state is a TCI-state activated by the CORESET with the smallest or largest index among the most recently received one or more CORESETs.

[0046] In combination with the first aspect, in some implementations of the first aspect, in the case where no activation signaling is received, the second TCI-state is a TCI-state activated by the CORESET with the smallest or largest index among the most recently received one or more CORESETs; wherein, the activation signaling is used to activate the TCI-state for PDSCH transmission.

[0047] In combination with the first aspect, in some implementations of the first aspect, the second TCI-state is the two TCI-states used for the most recent transmission of the second PDSCH, and the second PDSCH is transmitted using two TCI-states; or, the second TCI-state is the TCI-state in the TCI-state group with the smallest or largest corresponding TCI field value among multiple TCI-state groups for PDSCH transmission, and the TCI-state group includes two TCI-states; or, the second TCI-state is the two TCI-states used for transmitting the first PDCCH; or, the second TCI-state is the two currently activated TCI-states in the CORESET with the smallest or largest index among the one or more CORESETs received in the most recent time slot.

[0048] Optionally, the time interval between the second PDSCH and the PDCCH scheduling the second PDSCH is not less than the preset threshold value. For example, before this transmission, the network device has performed one or more PDSCH transmissions to this terminal device. Among them, some PDSCHs are transmitted using a single TCI-state, and some PDSCHs are transmitted using two TCI-states. Among the PDSCHs transmitted using two TCI-states, some PDSCHs have a scheduling time interval less than the preset threshold value, and some PDSCHs have a scheduling time interval not less than the preset threshold value. Then, the terminal device can use the TCI-state used for the PDSCH that was most recently transmitted using two TCI-states and has a scheduling time interval not less than the preset threshold value to receive and cache the signal.

[0049] In combination with the first aspect, in some implementations of the first aspect, the second TCI-state is the TCI-state in the TCI-state group corresponding to the smallest or largest TCI field value among multiple TCI-state groups for PDSCH transmission, and the TCI-state group includes two TCI-states.

[0050] In combination with the first aspect, in some implementations of the first aspect, the second TCI-state is the two TCI-states used for transmitting the first PDCCH.

[0051] In combination with the first aspect, in some implementations of the first aspect, the second TCI-state is the two currently active TCI-states in a CORESET (e.g., the CORESET with the smallest or largest index) among one or more CORESETs received most recently (e.g., in the most recent time slot).

[0052] In combination with the first aspect, in some implementations of the first aspect, the method further includes: receiving a first signaling for activating one or more TCI-states for a CORESET, where the first signaling includes one or more of the following fields: a field for indicating the number of activated TCI-states, a field for indicating whether the number of activated TCI-states is single or multiple.

[0053] The first signaling may be a MAC-CE signaling, an RRC signaling, or a DCI signaling, and the embodiments of the present application do not limit this. The above first signaling may be sent by a network device to a terminal device before sending the first PDCCH.

[0054] In combination with the first aspect, in some implementations of the first aspect, the method further includes: determining whether the network device uses two TCI-states to transmit the first PDSCH according to the currently active multiple groups of TCI-states for PDSCH transmission; if there is at least one TCI-state group including two TCI-states among the currently active multiple groups of TCI-states for PDSCH transmission, it is determined that the network device uses two TCI-states to send the first PDSCH.

[0055] Second aspect, another data transmission method is provided, including: receiving a first physical downlink control channel (PDCCH), where the first PDCCH is used to schedule a first physical downlink shared channel (PDSCH); receiving a downlink signal using a first transmission configuration indication state (TCI-state); obtaining a time interval between the first PDCCH and the first PDSCH; if the time interval is greater than or equal to the preset threshold and the first PDCCH does not carry information of the TCI-state, determining a second TCI-state and receiving the first PDSCH using the second TCI-state.

[0056] In combination with the second aspect, in some implementation manners of the second aspect, the second TCI-state is the TCI-state included in the TCI-state group with the smallest or largest corresponding TCI field value in one or more TCI-state groups including a TCI-state used by the first PDCCH; or, the second TCI-state is the TCI-state included in the TCI-state group with the smallest or largest corresponding TCI field value in one or more TCI-state groups including a TCI-state activated by the CORESET with the smallest or largest index in one or more recently received CORESETs; where the TCI-state group corresponds to a TCI field value, and the TCI-state group includes one TCI-state or two TCI-states.

[0057] In combination with the second aspect, in some implementation manners of the second aspect, if there is no one or more TCI-state groups including a TCI-state used by the first PDCCH, then the second TCI-state is a TCI-state used by the first PDCCH; or, if there is no one or more TCI-state groups including a TCI-state activated by the CORESET with the smallest or largest index in one or more recently received CORESETs, then the second TCI-state is a TCI-state activated by the CORESET with the smallest or largest index in one or more recently received CORESETs.

[0058] In combination with the second aspect, in some implementations of the second aspect, in the case where an activation signaling is not received, the second TCI-state is a TCI-state adopted by the first PDCCH; or, the second TCI-state is a TCI-state activated by the CORESET with the smallest or largest index among one or more recently received CORESETs; wherein, the activation signaling is used to activate the TCI-state for PDSCH transmission.

[0059] In combination with the second aspect, in some implementations of the second aspect, the second TCI-state is two TCI-states adopted for the most recent transmission of the second PDSCH, and the second PDSCH is transmitted using two TCI-states; or, the second TCI-state is a TCI-state in the TCI-state group with the smallest or largest corresponding TCI field value among multiple TCI-state groups for PDSCH transmission, and the TCI-state group includes two TCI-states; or, the second TCI-state is two TCI-states adopted for transmitting the first PDCCH; or, the second TCI-state is two currently activated TCI-states in the CORESET with the smallest or largest index among one or more CORESETs received in the most recent time slot.

[0060] In a third aspect, another method for data transmission is provided, including: receiving N physical downlink control channels PDCCH, where the N PDCCH are respectively used to schedule N physical downlink shared channels PDSCH, and N is an integer greater than 1; receiving downlink signals using N transmission configuration indication states TCI-state; if the time interval between the first PDCCH among the N PDCCH and the first PDSCH corresponding to the first PDCCH is less than a preset threshold, then obtain the first PDSCH from the downlink signals received using the first TCI-state corresponding to the first PDCCH among the N TCI-states.

[0061] In the embodiments of the present application, the PDSCHs transmitted by two transmit / receive points (TRPs) can be regarded as two PDSCHs. Each of the PDSCHs corresponds to a TCI-state. Therefore, the terminal device can determine the default TCI-state of each PDSCH respectively. Therefore, the subsequent content of the embodiments of the present application is described for a single PDCCH and a single PDSCH scheduled by the PDCCH, that is, the method for determining the TCI-state of a single PDSCH is discussed, and the method for determining the TCI-state of other PDSCHs is the same as that of the single PDSCH.

[0062] In combination with the third aspect, in some implementation manners of the third aspect, the first TCI-state is the currently active TCI-state in the CORESET with the smallest or largest index in the first control resource set (CORESET) group received in the most recent time slot, where the first CORESET group is a CORESET group composed of CORESETs having the same index as the CORESET corresponding to the first PDCCH.

[0063] In combination with the third aspect, in some implementation manners of the third aspect, the index is an index related to the transmission site, where the CORESETs corresponding to the same transmission site adopt the same index, and the CORESETs corresponding to different transmission sites adopt different indexes.

[0064] In combination with the third aspect, in some implementation manners of the third aspect, receiving the downlink signal by using N transmission configuration indication states (TCI-states) includes: receiving the downlink signal by using the first TCI-state in a first time interval, where the first time interval is the first symbol or the last symbol of the first PDCCH, or a time interval composed of K consecutive symbols starting from the first symbol after the first PDCCH, and K is the number of symbols corresponding to the preset threshold.

[0065] In combination with the third aspect, in some implementation manners of the third aspect, receiving the downlink signal by using N transmission configuration indication states (TCI-states) includes: receiving the downlink signal by using the first TCI-state in a first time interval; receiving the downlink signal by using a second TCI-state among the N TCI-states in a second time interval; where the transmission time of the first physical downlink control channel (PDCCH) is before the transmission time of the second PDCCH, and the time interval composed of K consecutive symbols starting from a first moment overlaps with the time interval composed of K consecutive symbols starting from a second moment, the first time interval is the first half of the time interval composed of the first moment to a third moment, the second time interval is the second half of the time interval composed of the first moment to the third moment, the first moment is the first symbol or the last symbol of the first PDCCH, or the first symbol after the first PDCCH, the second moment is the first symbol or the last symbol of the second PDCCH, or the first symbol after the second PDCCH, and the third moment is the Kth symbol after the second moment.

[0066] In a fourth aspect, another method for data transmission is provided, including: receiving downlink control information (DCI), where the DCI is used to schedule a physical downlink shared channel (PDSCH); receiving the PDSCH according to the DCI; where, when a preset condition is satisfied, the DCI and the PDSCH satisfy one or more of the following: the time interval between the reception time of the DCI and the PDSCH is greater than or equal to a preset threshold value; or, the DCI includes a transmission configuration indication (TCI) field value; the preset condition includes one or more of the following: the cell corresponding to the physical downlink control channel (PDCCH) transmitting the DCI is different from the cell corresponding to the PDSCH; the subcarrier spacing used by the DCI and the PDSCH is different; the transmission configuration indication state (TCI-state) for PDSCH transmission is not activated in the cell corresponding to the PDSCH; the control resource set (CORESET) is not configured in the cell corresponding to the PDSCH; the cell corresponding to the DCI uses a frequency in frequency range 1 (FR1) for transmission; the TCI-state including quasi co-location (QCL)-Type D information is not configured in the cell corresponding to the DCI.

[0067] It should be understood that the above "receiving the PDSCH according to the DCI" means determining the TCI-state according to the TCI field value in the DCI, so as to receive the PDSCH by using this TCI-state.

[0068] In combination with the fourth aspect, in some implementations of the fourth aspect, the preset conditions include: the cell corresponding to the PDCCH transmitting the DCI is different from the cell corresponding to the PDSCH; the TCI-state for PDSCH transmission is not activated in the cell corresponding to the PDSCH; and, the subcarrier spacing used for the DCI and the PDSCH is different.

[0069] In combination with the fourth aspect, in some implementations of the fourth aspect, the preset conditions include: the TCI-state for PDSCH transmission is not activated in the cell corresponding to the PDSCH; and, the subcarrier spacing used for the DCI and the PDSCH is different.

[0070] A fifth aspect provides another data transmission method, including: receiving downlink control information DCI, where the DCI is used to schedule a physical downlink shared channel PDSCH; receiving the PDSCH using a transmission configuration indication state TCI-state; where, when preset conditions are met, the TCI-state is the TCI-state used by the physical downlink control channel PDCCH transmitting the DCI, and the preset conditions include one or more of the following: the cell corresponding to the physical downlink control channel PDCCH transmitting the DCI is different from the cell corresponding to the PDSCH; the time interval between the reception times of the DCI and the PDSCH is greater than or equal to a preset threshold; the DCI does not include a TCI field value; the cell corresponding to the DCI uses a frequency in frequency range FR2 for transmission; the cell corresponding to the DCI is configured with a TCI-state including quasi-co-location QCL-TypeD information; the TCI-state for PDSCH transmission is not activated in the cell corresponding to the PDSCH; or, the cell corresponding to the PDSCH is not configured with a control resource set CORESET.

[0071] In combination with the fifth aspect, in some implementations of the fifth aspect, the preset conditions include: the cell corresponding to the PDCCH transmitting the DCI is different from the cell corresponding to the PDSCH; the cell corresponding to the DCI uses a frequency in frequency range FR2 for transmission; the DCI does not include a TCI field value; and the time interval between the reception times of the DCI and the PDSCH is greater than or equal to a preset threshold.

[0072] In a sixth aspect, another data transmission method is provided, including: receiving downlink control information (DCI), where the DCI is used to schedule a physical downlink shared channel (PDSCH); receiving the PDSCH using a transmission configuration indication state (TCI-state); where, when a preset condition is met, the TCI-state is the TCI-state activated by the CORESET with the smallest index among at least one CORESET that was last listened to in the currently active bandwidth part (BWP) of the cell corresponding to the DCI of the terminal device, and the preset condition includes one or more of the following: the cell corresponding to the physical downlink control channel (PDCCH) that transmits the DCI is different from the cell corresponding to the PDSCH; the time interval between the DCI and the reception time of the PDSCH is less than a preset threshold; the cell corresponding to the DCI uses a frequency in frequency range FR2 for transmission; the cell corresponding to the DCI is configured with a TCI-state including quasi co-location (QCL)-TypeD information; the TCI-state for PDSCH transmission is not activated in the cell corresponding to the PDSCH; the cell corresponding to the PDSCH is not configured with a control resource set (CORESET).

[0073] In combination with the sixth aspect, in some implementations of the sixth aspect, the preset condition includes: the cell corresponding to the PDCCH that transmits the DCI is different from the cell corresponding to the PDSCH; the cell corresponding to the DCI uses a frequency in frequency range FR2 for transmission; the time interval between the DCI and the reception time of the PDSCH is less than a preset threshold; and the TCI-state for PDSCH transmission is not activated in the cell corresponding to the PDSCH.

[0074] In a seventh aspect, another data transmission method is provided, including: receiving a first signaling, where the first signaling is used to activate multiple groups of transmission configuration indication states (TCI states), and each group of TCI states in the multiple groups of TCI states includes one or two TCI states; determining a mapping manner between each TCI state and a TCI field value according to the configuration information of a control resource set (CORESET) or the indication information in the first signaling.

[0075] In an embodiment of this application, the network device can simultaneously activate the TCI-states for two transmission and reception points (TRPs) through the above first signaling to enable multi-TRP transmission. In a possible implementation, the first signaling can be a MAC CE signaling.

[0076] In combination with the seventh aspect, in some implementations of the seventh aspect, the mapping method includes a first mapping method. Under the first mapping method, among the multiple TCI state groups, the j-th TCI state in the i-th TCI state group represents the j-th TCI state corresponding to the TCI field value i, where i is an integer greater than or equal to 0 and j is a positive integer. Therefore, under the first mapping method, one TCI field value corresponds to one or two TCI states.

[0077] In combination with the seventh aspect, in some implementations of the seventh aspect, the mapping method includes a second mapping method. Under the second mapping method, among the multiple TCI state groups, the j-th TCI state in the i-th TCI state group represents the TCI state corresponding to the TCI field value i in the PDCCH corresponding to the CORESET with the grouping index value of j - 1, where i is an integer greater than or equal to 0 and j is a positive integer. Therefore, under the second mapping method, one TCI field value corresponds to one TCI state.

[0078] In combination with the seventh aspect, in some implementations of the seventh aspect, each CORESET is associated with a grouping index value, and the CORESETs with the same grouping index value are grouped together.

[0079] In combination with the seventh aspect, in some implementations of the seventh aspect, when the grouping index values of the configured CORESETs include two different values in total, the mapping method is the second mapping method; or, when the grouping index values of the configured CORESETs include one value in total, the mapping method is the first mapping method.

[0080] In combination with the seventh aspect, in some implementations of the seventh aspect, when the value of the first field in the first signaling is 0, the mapping method is the first mapping method; or, when the value of the first field in the first signaling is 1, the mapping method is the second mapping method.

[0081] In combination with the seventh aspect, in some implementations of the seventh aspect, when the value of the first field in the first signaling is 1, the mapping method is the first mapping method; or, when the value of the first field in the first signaling is 0, the mapping method is the second mapping method.

[0082] In combination with the seventh aspect, in some implementations of the seventh aspect, the first field is the field composed of the first bit in the first signaling.

[0083] In combination with the seventh aspect, in some implementations of the seventh aspect, in the first signaling, before the field corresponding to the last TCI state in the TCI state group i in the multiple TCI state groups, a second field is included, and the second field is used to indicate whether there is a TCI state group i+1 in the multiple TCI state groups, where i is an integer greater than or equal to 0.

[0084] In combination with the seventh aspect, in some implementations of the seventh aspect, before receiving the first signaling, the method further includes: sending terminal capability parameters, where the terminal capability parameters include one or more of the following:

[0085] A first capability parameter, used to indicate the upper limit value of the number of different TCI states corresponding to a CORESET associated with one packet index value when the configured CORESET is associated with two different packet index values;

[0086] A second capability parameter, used to indicate the upper limit value of the number of different TCI states corresponding to the configured CORESET when the configured CORESET is associated with two different packet index values;

[0087] A third capability parameter, used to indicate the upper limit value of the number of different TCI states corresponding to the configured CORESET when the configured CORESET is associated with the same packet index value;

[0088] A fourth capability parameter, used to indicate the upper limit value of the number of different TCI states in the TCI states indicated by the first signaling;

[0089] A fifth capability parameter, used to indicate the upper limit value of the number of different TCI states in the TCI states indicated by the first signaling when the configured CORESET is associated with two different packet index values;

[0090] A sixth capability parameter, used to indicate the upper limit value of the number of different TCI states in the TCI states indicated by the first signaling when the configured CORESET is associated with the same packet index value;

[0091] A seventh capability parameter, used to indicate the upper limit value of the number of different TCI states in the TCI states indicated by the first signaling when using the first mapping method; or,

[0092] An eighth capability parameter, used to indicate the upper limit value of the number of different TCI states in the TCI states indicated by the first signaling when using the second mapping method.

[0093] In an embodiment of the present application, the above different capability parameters reflect the terminal capabilities at different granularities. The terminal device can flexibly report all or part of the capability parameters based on the actual situation, so that the TCI state activated by the network device for the terminal device through the first signaling meets the capabilities of the terminal device, thereby improving the subsequent data transmission efficiency.

[0094] In a eighth aspect, another data transmission method is provided, including: determining a first signaling, where the first signaling is used to activate multiple Transmission Configuration Indicator (TCI) state groups, and each TCI state group in the multiple TCI state groups includes one or two TCI states, and the mapping method between each TCI state and the TCI field value is determined according to the configuration information of the Control Resource Set (CORESET) or the indication information in the first signaling; sending the first signaling.

[0095] In combination with the eighth aspect, in some implementation manners of the eighth aspect, the mapping method includes a first mapping method. In the first mapping method, in the multiple TCI state groups, the j-th TCI state in the i-th TCI state group represents the j-th TCI state corresponding to the TCI field value i, where i is an integer greater than or equal to 0, and j is a positive integer. Therefore, in the first mapping method, one TCI field value corresponds to one or two TCI states.

[0096] In combination with the eighth aspect, in some implementation manners of the eighth aspect, the mapping method includes a second mapping method. In the second mapping method, in the multiple TCI state groups, the j-th TCI state in the i-th TCI state group represents the TCI state corresponding to the TCI field value i in the Physical Downlink Control Channel (PDCCH) corresponding to the CORESET with the grouping index value of j - 1, where i is an integer greater than or equal to 0, and j is a positive integer. Therefore, in the second mapping method, one TCI field value corresponds to one TCI state.

[0097] In combination with the eighth aspect, in some implementation manners of the eighth aspect, each CORESET is associated with a grouping index value, and the CORESETs with the same grouping index value are grouped as one group.

[0098] In combination with the eighth aspect, in some implementation manners of the eighth aspect, when the grouping index values of the configured CORESETs altogether include two different values, the mapping method is the second mapping method; or, when the grouping index values of the configured CORESETs altogether include one value, the mapping method is the first mapping method.

[0099] In combination with the eighth aspect, in some implementations of the eighth aspect, when the value of the first field in the first signaling is 0, the mapping method is the first mapping method; or, when the value of the first field in the first signaling is 1, the mapping method is the second mapping method.

[0100] In combination with the eighth aspect, in some implementations of the eighth aspect, when the value of the first field in the first signaling is 1, the mapping method is the first mapping method; or, when the value of the first field in the first signaling is 0, the mapping method is the second mapping method.

[0101] In combination with the eighth aspect, in some implementations of the eighth aspect, the first field is a field composed of the first bit in the first signaling.

[0102] In combination with the eighth aspect, in some implementations of the eighth aspect, in the first signaling, before the field corresponding to the last TCI state in the TCI state group i in the multiple TCI state groups, a second field is included, and the second field is used to indicate whether there is a TCI state group i+1 in the multiple TCI state groups, where i is an integer greater than or equal to 0.

[0103] In combination with the eighth aspect, in some implementations of the eighth aspect, before determining the first signaling, the method further includes: receiving terminal capability parameters, where the terminal capability parameters include one or more of the following:

[0104] The first capability parameter is used to indicate the upper limit value of the number of different TCI states corresponding to the CORESET associated with one packet index value when the configured CORESET associates two different packet index values;

[0105] The second capability parameter is used to indicate the upper limit value of the number of different TCI states corresponding to the configured CORESET when the configured CORESET associates two different packet index values;

[0106] The third capability parameter is used to indicate the upper limit value of the number of different TCI states corresponding to the configured CORESET when the configured CORESET associates the same packet index value;

[0107] The fourth capability parameter is used to indicate the upper limit value of the number of different TCI states in the TCI states indicated by the first signaling;

[0108] The fifth capability parameter is used to indicate the upper limit of the number of different TCI states in the TCI states indicated by the first signaling when the configured CORESET is associated with two different packet index values;

[0109] The sixth capability parameter is used to indicate the upper limit of the number of different TCI states in the TCI states indicated by the first signaling when the configured CORESET is associated with the same packet index value; or,

[0110] The seventh capability parameter is used to indicate the upper limit of the number of different TCI states in the TCI states indicated by the first signaling when using the first mapping method; or,

[0111] The eighth capability parameter is used to indicate the upper limit of the number of different TCI states in the TCI states indicated by the first signaling when using the second mapping method.

[0112] In a ninth aspect, there is provided an apparatus for data transmission, which is used to execute the method in any possible implementation manner of the above aspects. Specifically, the apparatus includes units for executing the method in any possible implementation manner of the above aspects.

[0113] In a tenth aspect, there is provided an apparatus for data transmission, including a processor, which is coupled to a memory and can be used to execute instructions in the memory to implement the method in any possible implementation manner of the above aspects. Optionally, the apparatus further includes a memory. Optionally, the apparatus further includes a communication interface, and the processor is coupled to the communication interface.

[0114] In one implementation manner, the apparatus for data transmission is a terminal device. When the apparatus for data transmission is a terminal device, the communication interface may be a transceiver or an input / output interface.

[0115] In another implementation manner, the apparatus for data transmission is a chip configured in a terminal device. When the apparatus for data transmission is a chip configured in a terminal device, the communication interface may be an input / output interface.

[0116] In an eleventh aspect, there is provided a processor, including: an input circuit, an output circuit, and a processing circuit. The processing circuit is used 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 manner of the above aspects.

[0117] In the specific implementation process, the above-mentioned 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 transistors, gate circuits, flip-flops, and various logic circuits, etc. The input signal received by the input circuit can be received and input by, for example but not limited to, a receiver. The signal output by the output circuit can be output to, for example but not limited to, a transmitter and transmitted by the transmitter. Moreover, the input circuit and the output circuit can be the same circuit, which serves as the input circuit and the output circuit at different times respectively. The embodiments of the present application do not limit the specific implementation manners of the processor and various circuits.

[0118] In a twelfth aspect, a processing device is provided, including 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 execute the methods in any one of the possible implementation manners in the above aspects.

[0119] Optionally, the processor is one or more, and the memory is one or more.

[0120] Optionally, the memory can be integrated with the processor, or the memory is separately arranged from the processor.

[0121] In the specific implementation process, the memory can be a non-transitory memory, such as a read only memory (ROM). It can be integrated with the processor on the same chip or separately arranged on different chips. The embodiments of the present application do not limit the type of the memory and the arrangement manner of the memory and the processor.

[0122] It should be understood that relevant data interaction processes, such as sending indication information, can be the process of outputting indication information from the processor, and receiving capability information can be the process of the processor receiving input capability information. Specifically, the data output by the processing can be output to the transmitter, and the input data received by the processor can come from the receiver. Among them, the transmitter and the receiver can be collectively referred to as a transceiver.

[0123] The processing device in the above twelfth aspect can be a chip. The processor can be implemented by hardware or by software. When implemented by hardware, the processor can be a logic circuit, an integrated circuit, etc.; when implemented by software, the processor can be a general-purpose processor, which is implemented by reading software code stored in the memory. The memory can be integrated in the processor or can be located outside the processor and exist independently.

[0124] In a thirteenth aspect, a computer program product is provided, which includes a computer program (which may also be referred to as code or instructions). When the computer program is run, it causes a computer to execute the method in any one of the possible implementation manners in the foregoing aspects.

[0125] In a fourteenth aspect, a computer-readable medium is provided. The computer-readable medium stores a computer program (which may also be referred to as code or instructions). When it runs on a computer, it causes the computer to execute the method in any one of the possible implementation manners in the foregoing aspects.

[0126] In a fifteenth aspect, a communication system is provided, which includes the foregoing terminal device and network device. BRIEF DESCRIPTION OF THE DRAWINGS

[0127] Figure 1 FIG. shows a schematic diagram of a communication system according to an embodiment of the present application.

[0128] Figure 2 FIG. shows a schematic diagram of the relationship between PDCCH and PDSCH according to an embodiment of the present application.

[0129] Figure 3 FIG. shows a schematic diagram of a data transmission scenario according to an embodiment of the present application.

[0130] Figure 4 FIG. shows a schematic flowchart of a data transmission method according to an embodiment of the present application.

[0131] Figure 5 FIG. shows a schematic diagram of the format of a signaling for activating a TCI-state according to an embodiment of the present application.

[0132] Figure 6 FIG. shows a schematic diagram of another data transmission scenario according to an embodiment of the present application.

[0133] Figure 7 FIG. shows a schematic flowchart of another data transmission method according to an embodiment of the present application.

[0134] Figure 8 FIG. shows a schematic diagram of using two TCI-states to cache downlink signals according to an embodiment of the present application.

[0135] Figure 9 FIG. shows a schematic diagram of another use of two TCI-states to cache downlink signals according to an embodiment of the present application.

[0136] Figure 10 FIG. shows a schematic diagram of another data transmission scenario according to an embodiment of the present application.

[0137] Figure 11A schematic block diagram of the data transmission device according to the embodiment of the present application is shown.

[0138] Figure 12 A schematic block diagram of another data transmission device according to the embodiment of the present application is shown.

[0139] Figure 13 A schematic diagram of the format of the MAC CE signaling for activating the TCI-state according to the embodiment of the present application is shown. Detailed implementation manners

[0140] The technical solutions in the present application will be described below with reference to the accompanying drawings.

[0141] The technical solutions of the embodiments of the present application can be applied to various communication systems, such as: Global System for Mobile Communications (GSM) system, Code Division Multiple Access (CDMA) system, Wideband Code Division Multiple Access (WCDMA) system, General Packet Radio Service (GPRS), Long Term Evolution (LTE) system, LTE Frequency Division Duplex (FDD) system, LTE Time Division Duplex (TDD), Universal Mobile Telecommunication System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX) communication system, future 5th generation (5G) system or New Radio (NR), etc.

[0142] It should also be understood that the technical solutions of the embodiments of the present application can also be applied to various communication systems based on non-orthogonal multiple access technologies, such as sparse code multiple access (SCMA) systems. Of course, SCMA may also be referred to by other names in the communication field. Further, the technical solutions of the embodiments of the present application can be applied to multi-carrier transmission systems that adopt non-orthogonal multiple access technologies, such as orthogonal frequency division multiplexing (OFDM), filter bank multi-carrier (FBMC), generalized frequency division multiplexing (GFDM), filtered-orthogonal frequency division multiplexing (F-OFDM) systems, etc. that adopt non-orthogonal multiple access technologies.

[0143] To facilitate the understanding of the embodiments of the present application, first, in combination with Figure 1 a detailed description will be given of the communication system applicable to the embodiments of the present application. Figure 1 FIG. shows a schematic diagram of a communication system 100 applicable to the embodiments of the present application. As Figure 1 shown, the communication system 100 may include at least one network device, such as Figure 1 the network device 110 shown; the communication system 100 may also include at least one terminal device, such as Figure 1 the terminal device 120 shown. The network device 110 and the terminal device 120 can communicate through a wireless link. Each communication device, such as the network device 110 or the terminal device 120, may be configured with multiple antennas. The multiple antennas may include at least one transmit antenna for transmitting signals and at least one receive antenna for receiving signals. Additionally, each communication device further includes a transmitter chain and a receiver chain. Those of ordinary skill in the art can understand that they may both include multiple components related to signal transmission and reception (such as a processor, a modulator, a multiplexer, a demodulator, a demultiplexer, or an antenna, etc.). Therefore, the network device 110 and the terminal device 120 can communicate through multi-antenna technology.

[0144] The terminal device in the embodiments of the present application can communicate with one or more core networks via a radio access network (RAN). The terminal device can be referred to as an access terminal, user equipment (UE), user unit, user station, mobile station, mobile terminal, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent, or user device. The access terminal can be a cellular phone, cordless phone, session initiation protocol (SIP) phone, wireless local loop (WLL) station, personal digital assistant (PDA), handheld device with wireless communication function, computing device, or other processing device connected to a wireless modem, in-vehicle device, wearable device, terminal device in a future 5G network, or terminal device in a future evolved public land mobile network (PLMN), etc.

[0145] The network device in the embodiments of the present application can be a device for communicating with the terminal device. The network device can be a base transceiver station (BTS) in a global system for mobile communications (GSM) system or a code division multiple access (CDMA) system, or a NodeB (NB) in a wideband code division multiple access (WCDMA) system, or an evolved NodeB (eNB or eNodeB) in an LTE system, or a radio controller in a cloud radio access network (CRAN) scenario, or the network device can be a relay station, access point, in-vehicle device, wearable device, network device in a future 5G network, or network device in a future evolved PLMN. The embodiments of the present application do not limit this. For example, the network device is a gNB in an NR system, or a transmission point (TRP or TP), one or a group (including multiple antenna panels) of antenna panels of a base station in a 5G system, or can also be a network node constituting the gNB or the transmission point, such as a baseband unit (BBU), or a distributed unit (DU), etc.

[0146] In some deployments, the gNB may include a centralized unit (CU) and a DU. The gNB may also include a radio frequency unit (RRU). The CU implements some functions of the gNB, and the DU implements some functions of the gNB. For example, the CU implements the functions of the radio resource control (RRC) and packet data convergence protocol (PDCP) layers, and the DU implements the functions of the radio link control (RLC) layer, medium / media access control (MAC) layer, and physical layer (PHY). Since the information of the RRC layer will ultimately become the information of the PHY layer, or is transformed from the information of the PHY layer, therefore, in this architecture, high-layer signaling, such as RRC layer signaling, can also be considered to be sent by the DU, or sent by the DU + CU. It can be understood that the network device can be a CU node, or a DU node, or a device including a CU node and a DU node. In addition, the CU can be classified as a network device in the radio access network (RAN), or the CU can be classified as a network device in the core network (CN), and this application does not make a limitation on this.

[0147] The above-mentioned network device can also generally refer to the general term of all devices at the network end. For example, when multiple TRPs are used to transmit data to the terminal device, the multiple TRPs can be collectively referred to as the network device.

[0148] In the embodiments of the present application, a terminal device or a network device includes a hardware layer, an operating system layer running on top of the hardware layer, and an application layer running on the operating system layer. The hardware layer includes hardware such as a central processing unit (CPU), a memory management unit (MMU), and a memory (also referred to as main memory). The operating system can be any one or more computer operating systems that implement service processing through processes. For example, Linux operating system, Unix operating system, Android operating system, iOS operating system, or Windows operating system, etc. The application layer includes applications such as a browser, an address book, a word processing software, an instant messaging software, etc. Moreover, the embodiments of the present application do not particularly limit the specific structure of the execution subject of the method provided in the embodiments of the present application. As long as it can communicate according to the method provided in the embodiments of the present application by running a program recorded with the code of the method provided in the embodiments of the present application. For example, the execution subject of the method provided in the embodiments of the present application can be a terminal device or a network device, or a functional module in the terminal device or the network device that can call and execute the program.

[0149] In addition, various aspects or features of the present application can be implemented as a method, an apparatus, or an article of manufacture using standard programming and / or engineering techniques. The term "article of manufacture" used in the present application covers a computer program accessible from any computer-readable device, carrier, or medium. For example, computer-readable media can include, but are not limited to: magnetic storage devices (such as hard disks, floppy disks, or magnetic tapes, etc.), optical discs (such as compact discs (CDs), digital versatile discs (DVDs), etc.), smart cards, and flash memory devices (such as erasable programmable read-only memories (EPROMs), cards, sticks, or key drives, etc.). Additionally, the various storage media described herein can represent one or more devices and / or other machine-readable media for storing information. The term "machine-readable media" can include, but is not limited to, wireless channels and various other media capable of storing, containing, and / or carrying instructions and / or data.

[0150] The embodiments of the present application can be applicable to LTE systems and subsequent evolved systems such as 5G, etc., or other wireless communication systems using various radio access technologies, such as systems using code division multiple access, frequency division multiple access, time division multiple access, orthogonal frequency division multiple access, single-carrier frequency division multiple access and other access technologies. It is particularly applicable to scenarios that require channel information feedback and / or apply two-level precoding technology, such as wireless networks applying Massive MIMO technology, wireless networks applying distributed antenna technology, etc.

[0151] It should be understood that the multiple-input multiple-output (MIMO) technology refers to using multiple transmit antennas and multiple receive antennas at the transmitting-end device and the receiving-end device respectively, so that signals are transmitted and received through the multiple antennas of the transmitting-end device and the receiving-end device, thereby improving the communication quality. It can make full use of spatial resources, achieve multiple-input multiple-output through multiple antennas, and can double the system channel capacity without increasing the spectrum resources and the antenna transmit power.

[0152] For ease of understanding, the following first introduces the relevant terms involved in the embodiments of the present application.

[0153] 1. Beam

[0154] The manifestation of a beam in the NR protocol can be a spatial domain filter, or a spatial filter or a spatial parameter. The beam used to transmit a signal can be called a transmit beam (Tx beam), and can be called a spatial domain transmission filter or a spatial transmission parameter; the beam used to receive a signal can be called a receive beam (Rx beam), and can be called a spatial domain receive filter or a spatial RX parameter.

[0155] The transmit beam can refer to the distribution of the signal intensity formed in different directions in space after the signal is transmitted by the antenna, and the receive beam can refer to the signal intensity distribution of the wireless signal received by the antenna in different directions in space.

[0156] There is a pairing relationship between the transmit beam and the receive beam. The pairing relationship between the transmit beam and the receive beam can also be called the pairing relationship between the spatial transmission filter and the spatial receive filter. Transmitting a signal between the transmit beam and the receive beam with a beam pairing relationship can obtain a large beamforming gain.

[0157] In one implementation, the transmitting end can send a reference signal by means of beam scanning, and the receiving end can also receive the reference signal by means of beam scanning. Specifically, the transmitting end can form beams with different directivities in space through beamforming, and can poll on multiple beams with different directivities to transmit the reference signal through the beams with different directivities, so that the power of the reference signal transmitted in the direction pointed by the transmitting beam can reach the maximum. The receiving end can also form beams with different directivities in space through beamforming, and can poll on multiple beams with different directivities to receive the reference signal through the beams with different directivities, so that the power of the reference signal received by the receiving end can reach the maximum in the direction pointed by the receiving beam.

[0158] By traversing each transmitting beam and receiving beam, the receiving end can perform channel measurement based on the received reference signal, and report the measurement result to the transmitting end through channel state information (CSI). For example, the receiving end can report the part of the reference signal resources with larger reference signal received power (RSRP) to the transmitting end, such as reporting the identifier of the reference signal resources, so that the transmitting end can use the beam pairing relationship with better channel quality to transmit and receive signals when transmitting data or signaling.

[0159] In addition, the beam can be a wide beam, or a narrow beam, or other types of beams. The technology for forming the beam can be beamforming technology or other technologies. The beamforming technology can specifically be digital beamforming technology, analog beamforming technology, or hybrid digital / analog beamforming technology, etc.

[0160] The beam generally corresponds to resources. For example, when performing beam measurement, the network device measures different beams through different resources, and the terminal device feeds back the measured resource quality, so that the network device knows the quality of the corresponding beam. During data transmission, the beam information is also indicated through its corresponding resources. For example, the network device indicates the beam information of the terminal device's PDSCH through the resources in the TCI of the DCI.

[0161] Optionally, multiple beams with the same or similar communication characteristics are regarded as one beam. One beam can include one or more antenna ports for transmitting data channels, control channels, sounding signals, etc. The one or more antenna ports forming one beam can also be regarded as an antenna port set.

[0162] In the embodiments of the present application, if not otherwise specified, a beam refers to the transmission beam of a network device. In beam measurement, each beam of the network device corresponds to a resource, so the beam corresponding to the resource can be uniquely identified by the index of the resource.

[0163] 2. Resource

[0164] In beam measurement, the beam corresponding to the resource can be uniquely identified by the index of the resource. The resource can be an uplink signal resource or a downlink signal resource. The uplink signal includes, but is not limited to, a sounding reference signal (SRS) and a demodulation reference signal (DMRS). The downlink signal includes, but is not limited to: a channel state information reference signal (CSI-RS), a cell-specific reference signal (CS-RS), a user equipment specific reference signal (UE-specific RS), a demodulation reference signal (DMRS), and a synchronization signal / physical broadcast channel block (SS / PBCH block). Among them, the SS / PBCH block can be abbreviated as a synchronization signal block (SSB).

[0165] The resource can be configured by radio resource control (RRC) signaling. In terms of the configuration structure, a resource is a data structure, including the relevant parameters of its corresponding uplink / downlink signal, such as the type of the uplink / downlink signal, the resource granule carrying the uplink / downlink signal, the transmission time and period of the uplink / downlink signal, the number of ports used to transmit the uplink / downlink signal, etc. Each uplink / downlink signal resource has a unique index to identify the resource of the downlink signal. It can be understood that the index of the resource can also be referred to as the identifier of the resource, and the embodiments of the present application do not make any restrictions on this.

[0166] 3. TCI-state

[0167] The TCI-state can also be expressed as TCI state, that is, in this application, TCI-state is equivalent to TCI state. The TCI-state is configured by the network device for each terminal device through TCI. The TCI-state includes its own index tci-StateId and two QCL-Info. Each QCL-Info includes a cell field and a BWP-Id, which respectively indicate which cell and which bandwidth part (BWP) of the cell the TCI-state is applied to, that is, different cells or different BWPs of the same cell can be configured with different QCL-Info. The QCL-Info also includes a reference signal referenceSignal field, which is used to indicate which reference signal resource forms a quasi-colocation (QCL) relationship with. Therefore, the TCI-state can also be expressed as a QCL hypothesis.

[0168] Since the term "beam" generally does not directly appear in the protocol, the beam is generally replaced by other terms. For example, in data transmission and channel measurement, the beam corresponds to the reference signal resource, and one beam corresponds to one reference signal resource. Therefore, the "which reference signal resource forms a QCL relationship with" described in the embodiments of this application actually refers to which beam forms a QCL relationship with. The QCL relationship means that two reference signal resources (or two antenna ports) have certain same spatial parameters, and the above antenna ports and reference signal resources are in one-to-one correspondence. Specifically, which spatial parameters are the same depends on the type of the QCL-Info, that is, another field QCL-Type of the QCL-Info. The QCL-Type can have four values {typeA, typeB, typeC, typeD}. Taking typeD as an example, typeD means that two reference signal resources have the same spatial reception parameter information, that is, two beams have the same reception beam. At most one of the two QCL-Info included in the TCI-state can be of TypeD.

[0169] The following uses an example to specifically elaborate on how the network device based on the version 15 (release 15, R15) protocol uses the TCI-state to indicate the reception beam information of the data transmission beam to a terminal device, including the configuration, activation, and indication of the TCI-state.

[0170] (1) TCI-state configuration: The network device configures multiple TCI-states for the terminal device through RRC signaling. Each of these TCI-states includes a QCL-Info of type D. The network device can also configure TCI-states that do not include QCL-info of type D, but these TCI-states are not used for indicating data transmission beams, so they will not be elaborated further here.

[0171] (2) TCI-state activation: The TCI field in DCI is 3 bits, corresponding to 8 field values. Each field value can indicate a TCI-state, that is, it can indicate at most one of the 8 TCI-states. However, the protocol stipulates that the network device can configure up to 128 TCI-states for the terminal device. Then which 8 of the 128 TCI-states do these 8 TCI field values correspond to? This is indicated by the network device through signaling (such as medium / media access control-control element (MAC-CE) signaling). Specifically, after the network device configures multiple TCI-states, it activates 8 of them through MAC-CE signaling. These 8 TCI states correspond one-to-one with the 8 values of the TCI field in DCI. That is, which 8 TCI-states the 8 values of the TCI field in DCI correspond to is determined through MAC-CE signaling. In the MAC-CE used to activate TCI, the size of each field corresponding to each TCI-state is 1 bit. A value of 1 indicates activation of the TCI-state, and a value of 0 indicates non-activation. Theoretically, a MAC-CE signaling can have 8 activation fields with a value of 1, and the rest are all 0. The TCI-states corresponding to these 8 fields with a value of 1 are the 8 TCI-states corresponding to the 8 values of the TCI field in DCI. For example, the minimum value 000 of the TCI field corresponds to the TCI-state with the smallest activated index in the MAC CE, and so on, one-to-one correspondence. It should be understood that there are many types of MAC-CE. In addition to the MAC-CE used for TCI-state activation, there are many other MAC-CEs for other purposes. This application only relates to the MAC-CE for TCI-state / TCI-state combination activation. Therefore, unless otherwise specified, the MAC-CE mentioned in this application refers to this type of MAC-CE.

[0172] (3) TCI-state Indication: The network device indicates a specific TCI-state through the TCI field in DCI. For example, if the value of the TCI field in the DCI sent by the network device to the terminal device is 000, it means that the data transmission beam adopts the TCI-state corresponding to 000. The referenceSignal included in the QCL-Info of type typeD in this TCI-state is the channel state information reference signal (CSI-RS) with index #1, indicating that the beam used for data transmission has the same receiving beam as the CSI-RS with index #1. The receiving beam corresponding to the CSI-RS with index #1 can be determined through the beam measurement process and is known to the terminal device. Therefore, through the specific value of the TCI field, the terminal device can determine the receiving beam corresponding to the data transmission beam and thus receive data using the corresponding receiving beam.

[0173] Since the beam has a certain spatial directivity, the network device can generate different beams pointing in different transmission directions. In downlink data transmission, the network device will use a specific beam to send data to the terminal device and inform the terminal device of the transmission beam information it uses, so that the terminal device can receive the data sent by the network device using the correct receiving beam (i.e., the receiving beam corresponding to the transmission beam). As described above, in the R15 protocol, the relevant information of the transmission beam can be indicated through the transmission configuration indication (TCI) field in the downlink control information (DCI). The TCI field is 3 bits in size and can specifically represent 8 different values. Each value of the TCI field corresponds to an index of a TCI-state, which is used to uniquely identify a TCI-state. The TCI-state includes several parameters as described above, and the relevant information of the transmission beam can be determined through these parameters. For example, the TCI-state includes a reference signal resource, which is used to indicate the information of the transmission beam (there is a corresponding relationship between the reference signal resource and the beam). It should be understood that since the beam information is characterized by the TCI-state, determining the transmission beam information for data transmission can be equivalently expressed as determining the TCI-state for data transmission.

[0174] When a network device performs data transmission, it can use a single beam for transmission, or multiple beams or multiple TRPs for transmission simultaneously. When using a single beam to transmit data, the network device uses a single TCI-state, and the terminal device can determine a single TCI-state. When using multiple beams or multiple TRPs to transmit data, the network device will use multiple TCI-states (each beam or each TRP corresponds to a TCI-state), and the terminal device can determine multiple TCI-states. It should be understood that for the convenience of description, in the following, the case where two TRPs respectively use two TCI-states to transmit data is taken as an example for illustration, but the data transmission method proposed in this application is also applicable to the case of determining more than two TCI-states, and will not be elaborated further hereinafter.

[0175] It should be noted that in this application, since downlink data is sent on the physical downlink shared channel (PDSCH), downlink data can also be equivalently referred to as PDSCH. Since downlink control information is sent on the physical downlink control channel (PDCCH), downlink control information can be equivalently referred to as PDCCH.

[0176] In addition, in this application, beam, TRP, and TCI-state are equivalent. The meaning of using a single beam, TRP, or TCI-state to transmit PDSCH is the same. When using multiple TRPs, the network device generally refers to the overall composed of multiple TRPs.

[0177] Before introducing the method provided in the embodiments of this application, the following points are explained first.

[0178] First, in the embodiments of this application, "pre-defined" can be implemented by pre-saving corresponding codes, tables, or other means that can be used to indicate relevant information in the device (for example, including the terminal device and the network device), and this application does not limit its specific implementation manner.

[0179] Second, in the embodiments shown below, the terms and English abbreviations, such as downlink control information (DCI), media access control control element (MAC-CE), radio resource control (RRC), physical downlink control channel (PDCCH), physical downlink shared channel (PDSCH), channel state information reference signal (CSI-RS), etc., are all exemplary examples given for the convenience of description and should not constitute any limitation to this application. This application does not exclude the possibility of defining other terms that can achieve the same or similar functions in existing or future protocols.

[0180] Third, in the embodiments shown below, the first, second, and various numerical numbers are only for the convenience of description and are not used to limit the scope of the embodiments of the present application. For example, to distinguish different PDCCHs, different TCI-states, etc.

[0181] Fourth, the "protocol" involved in the embodiments of the present application may refer to a standard protocol in the communication field. For example, it may include the LTE protocol, the NR protocol, and related protocols applied to future communication systems. The present application does not make any limitations in this regard.

[0182] Fifth, "at least one" means one or more, and "multiple" means two or more. "And / or" describes the association relationship of associated objects and indicates that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone, where A and B can be singular or plural. The character " / " generally represents an "or" relationship between the associated objects before and after. "At least one (item)" or its similar expression refers to any combination of these items, including any combination of single item (item) or multiple items (items). For example, at least one (item) of a, b, and c can represent: a, or b, or c, or a and b, or a and c, or b and c, or a, b, and c, where a, b, and c can be single or multiple.

[0183] The method and apparatus for data transmission provided by the present application will be described in detail below with reference to the accompanying drawings. It should be understood that the technical solution of the present application can be applied to a wireless communication system. For example, Figure 1 the communication system 100 shown in Figure 1 There may be a wireless communication connection relationship between two communication devices in the wireless communication system. One of the two communication devices may correspond to Figure 1 the terminal device 120 shown in Figure 1 For example, it can be Figure 1 the terminal device shown in

[0184] Hereinafter, without loss of generality, the method for data transmission provided by the embodiments of the present application will be described in detail by taking the interaction process between the terminal device and the network device as an example.

[0185] Figure 2The figure shows a schematic diagram of the relationship between PDCCH and PDSCH in an embodiment of the present application. PDCCH is used to schedule PDSCH, and there needs to be a certain time interval between PDCCH and the PDSCH it schedules, which is used for the terminal device to receive and process the PDCCH, so as to determine the TCI-state of PDSCH according to the PDCCH. The time required for the terminal device to receive and process PDCCH is reported by the terminal device to the network device, which is called a preset threshold value in the present application (for example, the parameter timeDurationForQCL). Exemplarily, the terminal device may report the parameter timeDurationForQCL to the network device, and the value of this parameter is the time required for the terminal device to receive and process PDCCH.

[0186] Such as Figure 2As shown, when the time interval between the PDCCH and the PDSCH it schedules is not less than a preset threshold value, the terminal device can complete the reception and processing of the PDCCH before receiving the PDSCH, so as to determine the TCI-state of the PDSCH according to the PDCCH. When the time interval between the PDCCH and the PDSCH it schedules is less than the preset threshold value, the terminal device cannot determine the TCI-state of the PDSCH according to the PDCCH, because the terminal device has not completed the processing of the PDCCH when the PDSCH is sent. In order to successfully receive the PDSCH, the protocol stipulates the default TCI-state adopted in this case. The terminal device can complete the reception of the PDSCH through the default TCI-state. After the protocol agrees on the default TCI-state, the network device and the terminal device can send and receive data according to the default TCI-state. Exemplarily, when the network device sends a PDSCH, if the time interval between the PDSCH and its corresponding PDCCH is less than the preset threshold value, the network device will send the PDSCH using the default TCI-state. Before the terminal device completes the processing of the PDCCH, since it is not certain whether the network device has sent the PDSCH during the reception of the PDCCH, in order not to miss the PDSCH, the terminal device can use the receiving beam corresponding to the default TCI-state to receive all the signals within a period of time (a period of time starting from the symbol where the PDCCH is located and lasting for the preset threshold value) and cache them. After the terminal device completes the reception and processing of the PDCCH, it judges the time interval between the PDSCH scheduled by the PDCCH and the PDCCH. If the time interval is less than the preset threshold value, the terminal device can determine that the PDSCH is included in the cached signals, and determine the PDSCH from the cached signals according to the parameters indicated by the PDCCH (such as the time-frequency resource information of the PDSCH). If the time interval is not less than the preset threshold value, the terminal device can discard the cached signals and receive the PDSCH according to the TCI-state indicated in the PDCCH.

[0187] The data transmission method of the embodiments of the present application will be described in detail below for different data transmission scenarios.

[0188] The embodiments of the present application are described by taking the TCI-state as an example. However, it should be understood that in the present application, the TCI-state can also be expressed as a QCL assumption. For example, the first TCI-state in the following embodiments can be replaced with the first QCL assumption. Another example is that a QCL assumption adopted by the first PDCCH in the following embodiments refers to the QCL assumption used for the transmission of the first PDCCH in the CORESET corresponding to the first PDCCH. In the present application, the most recently received (such as received in the most recent time slot) CORESET can also be understood as the CORESET associated with the search space (such as the most recently listened search space in the most recent time slot).

[0189] Figure 3 FIG. shows a schematic diagram of a data transmission scenario according to an embodiment of the present application. This data transmission scenario is a multi-TRP transmission scenario based on a single PDCCH, that is, the network device sends the PDSCH to the terminal device through multiple TRPs. Among them, the PDSCH sent by each TRP can be the same PDSCH. For example, each TRP sends a part or all of the same PDSCH. The embodiments of the present application do not limit the number of PDSCHs sent by multiple TRPs. Each TRP uses a TCI-state to send the PDSCH. Therefore, the terminal device can determine multiple TCI-states to correctly receive the PDSCH. The above network device sending the PDCCH to the terminal device can be sent through a single TRP (using a single TCI-state) or through multiple TRPs (using multiple TCI-states). The embodiments of the present application do not limit this. For ease of description, Figure 3 FIG. shows two TRPs (that is, the terminal device can determine two TCI-states). Specifically, TRP 1 sends a PDCCH to the terminal device for scheduling the PDSCH of TRP1 and the PDSCH of TRP 2. TRP 1 uses TCI-state #1 to send the PDSCH to the terminal device, and TRP 2 uses TCI-state #2 to send the PDSCH to the terminal device. The terminal device determines TCI-state #1 and TCI-state #2 to correctly receive the PDSCH.

[0190] For Figure 3 the scenario shown in Figure 4 FIG. shows a schematic flowchart of a data transmission method 400 provided by an embodiment of the present application. The method 400 includes:

[0191] S410, The network device sends a first Physical Downlink Control Channel (PDCCH) to the terminal device. Correspondingly, the terminal device receives the first PDCCH from the network device, and the first PDCCH is used to schedule a first Physical Downlink Shared Channel (PDSCH). The first PDCCH may include transmission parameters of the first PDSCH sent by one or two Transmission and Reception Points (TRPs), such as the time-frequency resources for transmitting the first PDSCH, the Transmission Configuration Indicator (TCI)-state of the first PDSCH, etc.

[0192] Exemplarily, the network device may send a first PDCCH for scheduling the first PDSCH to the terminal device. As described above, when sending the first PDSCH, the network device may determine the time interval between the first PDSCH and the first PDCCH scheduling the first PDSCH. If the time interval between the first PDSCH and the first PDCCH is less than a preset threshold, the network device will send the first PDSCH using the default TCI-state. If the time interval between the first PDSCH and the first PDCCH is greater than or equal to the preset threshold, the network device may send the first PDSCH using the default TCI-state or other TCI-states, and carry the information indicating the TCI-state in the first PDCCH to inform the terminal device.

[0193] S420, The network device sends a downlink signal to the terminal device, and the terminal device receives the downlink signal from the network device using a first Transmission Configuration Indicator (TCI)-state. In the embodiments of the present application, the first TCI-state may be one TCI-state or two TCI-states.

[0194] Before the terminal device finishes processing the first PDCCH, since it is not certain whether the network device has sent the first PDSCH during the reception of the first PDCCH, in order not to miss the first PDSCH, the terminal device may use the receiving beam corresponding to the first TCI-state (which may also be referred to as the default TCI-state) to receive all the downlink signals for a period of time starting from the symbol where the PDCCH is located and lasting for a preset threshold, and cache them until the reception and processing of the first PDCCH are completed.

[0195] It should be understood that before receiving and caching the downlink signal, the terminal device may first determine whether the network device uses one TCI-state or two TCI-states for data transmission, so as to determine whether to use one TCI-state or two TCI-states to cache the downlink signal.

[0196] As an optional embodiment, the method further includes: The terminal device may determine, according to multiple currently active TCI-states for PDSCH transmission, whether the network device uses two TCI-states to transmit the first PDSCH, so as to determine whether to use two first TCI-states to receive the downlink signal. Each TCI-state group includes one TCI-state or two TCI-states, and one TCI-state group corresponds to one TCI field value in the DCI. If there is at least one TCI-state group containing two TCI-states among the multiple currently active TCI-states for PDSCH transmission, the terminal device determines that the network device uses two TCI-states to transmit the first PDSCH, and thus uses two first TCI-states to receive the downlink signal. Otherwise, the terminal device determines that the network device uses one TCI-state to transmit the first PDSCH, and thus uses one first TCI-state to receive the downlink signal.

[0197] As an optional embodiment, the method further includes: The terminal device may determine, according to multiple currently active TCI-states for PDSCH transmission, whether the network device uses two TCI-states to transmit the first PDSCH, so as to determine whether to use two first TCI-states to receive the downlink signal. Each TCI-state group includes one TCI-state or two TCI-states, and one TCI-state group corresponds to one TCI field value in the DCI. If all of the multiple currently active TCI-states for PDSCH transmission contain two TCI-states, the terminal device determines that the network device uses two TCI-states to transmit the first PDSCH, and thus uses two first TCI-states to receive the downlink signal. Otherwise, the terminal device determines that the network device uses one TCI-state to transmit the first PDSCH, and thus uses one first TCI-state to receive the downlink signal.

[0198] In an embodiment of the present application, the terminal device can determine whether the network device uses a single TCI-state or two TCI-states for data transmission according to the activation status of the TCI-state of the first PDSCH. Exemplarily, if the network device activates one TCI-state group or multiple TCI-state groups through an activation signaling (such as a MAC-CE signaling), and there is at least one TCI-state group including two TCI-states, or each TCI-state group includes two TCI-states (that is, there is one or more TCI field values in the TCI field of the DCI corresponding to two TCI-states at the same time), it indicates that the network device may use two TCI-states for simultaneous transmission. At this time, the terminal device determines to use one default TCI-state or two default TCI-states to cache the downlink signal. Otherwise, the terminal device determines to use one default TCI-state to cache the downlink signal.

[0199] Optionally, whether the terminal device can receive using two first TCI-states can be reported by the terminal device to the network device through a capability reporting process. That is, when the terminal capability information indicates support for transmitting the PDSCH using two default TCI-states, the two first TCI-states are used to receive the PDSCH; when the terminal capability information indicates non-support for transmitting the PDSCH using two default TCI-states, the one first TCI-state is used to receive the PDSCH.

[0200] S430, the terminal device obtains the time interval between the first PDCCH and the first PDSCH.

[0201] The time interval between the first PDCCH and the first PDSCH in the embodiment of the present application can also be referred to as the scheduling time interval of the first PDSCH, or the scheduling offset of the first PDSCH, or other names.

[0202] S440, if the time interval is less than a preset threshold, the terminal device obtains the first PDSCH from the downlink signal. The first PDSCH can be a partial PDSCH or a complete PDSCH, and the embodiment of the present application does not limit this. It should be understood that the first PDSCH being a partial PDSCH means that among the downlink signals received and cached by the terminal device, a part of the PDSCH is included, that is, a part of the first PDSCH. In other words, if the first PDSCH is a partial PDSCH, it means that part of the transmission time of the first PDSCH is within the above preset threshold and the other part is outside the preset threshold.

[0203] After the terminal device completes the reception and processing of the first PDCCH, it can determine the time interval between the first PDSCH scheduled by the first PDCCH and the first PDCCH. If the time interval is less than a preset threshold, the terminal device can determine that the first PDSCH is included in the cached downlink signal, and obtain the first PDSCH from the cached downlink signal according to the parameters indicated by the PDCCH (such as the time-frequency resource information of the PDSCH).

[0204] It should be understood that the preset threshold represents the time required for the terminal device to receive and process the PDCCH and prepare the reception beam for the PDSCH (that is, it may take a certain amount of time to switch to the reception beam of the PDSCH). Exemplarily, the terminal device can report the preset threshold to the network device through a terminal capability parameter (such as timeDurationForQCL). The present application does not limit the name of this terminal capability parameter to timeDurationForQCL. The time interval between the first PDCCH and the second PDSCH being less than the preset threshold means that the transmission time of the first PDSCH is before the completion of the reception of the first PDCCH. The condition "the time interval between the first PDCCH and the first PDSCH it schedules is less than the preset threshold" can also be replaced with other forms of conditions, as long as the condition can indicate that the transmission time of the first PDSCH is before the completion of the reception of the first PDCCH. Similarly, the condition "the time interval between the first PDCCH and the first PDSCH it schedules is not less than the preset threshold" can also be replaced with other forms of conditions, as long as the condition can indicate that the transmission time of the first PDSCH is after the completion of the reception of the first PDCCH.

[0205] The above condition "the time interval between the first PDCCH and the first PDSCH it schedules is less than a preset threshold" can also be replaced with "the time interval between the first PDCCH and the first PDSCH it schedules is less than or equal to a preset threshold". Correspondingly, the condition "the time interval between the first PDCCH and the first PDSCH it schedules is greater than or equal to a preset threshold" can also be replaced with "the time interval between the first PDCCH and the first PDSCH it schedules is greater than a preset threshold". That is, the "equal" case can be grouped together with the "less than" case or with the "greater than" case, and the embodiments of the present application do not limit this. It should be understood that the time interval between the PDSCH and its corresponding PDCCH can specifically refer to the time interval (interval) or time offset (offset) between the first symbol of the PDCCH and the first symbol of the PDSCH; or, the time interval between the PDSCH and its corresponding PDCCH can specifically refer to the time interval (interval) or time offset (offset) between the last symbol of the PDCCH and the first symbol of the PDSCH, and the embodiments of the present application do not limit this.

[0206] In the embodiments of the present application, a TCI-state group refers to a group of TCI-states activated by activation signaling for PDSCH transmission. Each TCI-state group corresponds to a field value of the TCI field in the DCI, and may include one TCI-state or multiple TCI-states. For example, there are 8 values in the TCI field of the DCI, which can correspond to 8 TCI-state groups, and these 8 TCI-state groups are indicated by activation signaling sent by the network device to the terminal device. The network device can use one TCI-state group for PDSCH transmission each time.

[0207] In the embodiments of the present application, the terminal device determines one first TCI-state or two first TCI-states to receive the downlink signal. That is, when the time interval between the first PDSCH and the first PDCCH is less than a preset threshold (such as TimeDurationForQCL), the terminal device can use one first TCI-state or two first TCI-states to receive the first PDSCH.

[0208] The first TCI-state in the embodiments of the present application can be determined by any one of the following multiple methods:

[0209] Method 1: The terminal device uses one TCI-state used by the first PDCCH as one of the first TCI-states, and then determines the above first TCI-state based on this one first TCI-state.

[0210] In a first possible implementation, the first TCI-state is a TCI-state included in one or more TCI-state groups that include a TCI-state used by the first PDCCH (for example, the TCI-state group corresponding to the smallest or largest TCI field value).

[0211] In other words, there may be one TCI-state group that includes a TCI-state used by the first PDCCH, or there may be multiple TCI-state groups that include a TCI-state used by the first PDCCH. If there is one TCI-state group that includes a TCI-state used by the first PDCCH, then the first TCI-state is the TCI-state included in this TCI-state group. If there are multiple TCI-state groups that include a TCI-state used by the first PDCCH, then the first TCI-state is the TCI-state included in the TCI-state group corresponding to the smallest or largest TCI field value among these multiple TCI-state groups.

[0212] Exemplarily, the terminal device may use a TCI-state used by the first PDCCH as one of the first TCI-states. Then, the terminal device determines all TCI-state groups that include the above one of the first TCI-states from at least one activated TCI-state group for PDSCH transmission (each TCI-state group corresponds to a TCI field value of the TCI field in the DCI). Finally, the terminal device selects one TCI-state group from these TCI-state groups (for example, the TCI-state group corresponding to the smallest or largest TCI field value), and uses all the TCI-states included in this TCI-state group as the first TCI-states used by the terminal device to receive the downlink signal. If the determined TCI-state group of the terminal device includes one TCI-state, then the first TCI-state is one TCI-state, that is, the terminal device uses one first TCI-state to receive the downlink signal; if the determined TCI-state group of the terminal device includes two TCI-states, then the first TCI-state is two TCI-states, that is, the terminal device uses two first TCI-states to receive the downlink signal.

[0213] In a second possible implementation, the first TCI-state is a TCI-state included in one or more TCI-state groups that include one TCI-state used by the first PDCCH and include two TCI-states (for example, the TCI-state group corresponding to the smallest or largest TCI field value).

[0214] In other words, there may be one TCI-state group that includes two TCI-states and includes one TCI-state used by the first PDCCH, or there may be multiple TCI-state groups that include two TCI-states and include one TCI-state used by the first PDCCH. If there is one TCI-state group that includes two TCI-states and includes the one TCI-state used by the first PDCCH, then the first TCI-state is the TCI-state included in this TCI-state group. If there are multiple TCI-state groups that include two TCI-states and include the one TCI-state used by the first PDCCH, then the first TCI-state is the TCI-state included in the TCI-state group with the smallest or largest corresponding TCI field value among these multiple TCI-state groups that include two TCI-states.

[0215] Exemplarily, the terminal device may use one of the TCI-states used by the first PDCCH as one of the first TCI-states. Then, the terminal device determines all TCI-state groups that contain one of the first TCI-states and contain two TCI-states from at least one activated TCI-state group for PDSCH transmission (each TCI-state group corresponds to a TCI field value of the TCI field in the DCI). Finally, the terminal device selects one TCI-state group from these TCI-state groups (for example, the TCI-state group corresponding to the smallest or largest TCI field value, or the TCI-state group with the smallest or largest index of the second TCI-state), and uses all the TCI-states contained in this TCI-state group as the first TCI-states. It should be understood that the above-mentioned second TCI-state refers to the other TCI-state in a TCI-state group that includes two TCI-states, excluding the one TCI-state used by the first PDCCH. The method of the embodiment of the present application can ensure that the TCI-state group determined by the terminal device must contain two TCI-states, so as to receive the downlink signal using two TCI-states.

[0216] In a third possible implementation manner, if there is no one or more TCI-state groups that contain one of the TCI-states used by the first PDCCH, the first TCI-state is one of the TCI-states used by the first PDCCH.

[0217] Exemplarily, the terminal device may first use the above-mentioned second possible implementation manner to determine two first TCI-states. If two first TCI-states cannot be determined by using the above-mentioned second possible implementation manner, that is, there is no TCI-state group that contains both one of the TCI-states used by the first PDCCH and two TCI-states, the terminal device may determine a unique first TCI-state. That is, the terminal device determines a TCI-state group that contains one of the TCI-states used by the first PDCCH from the TCI-state groups that contain two TCI-states. If there is no such TCI-state group, the terminal device may determine one of the TCI-states used by the first PDCCH as the unique first TCI-state, or, determine a TCI-state group that contains one of the TCI-states used by the first PDCCH from the TCI-state groups that contain one TCI-state.

[0218] It should be understood that the above "minimum or maximum" is for illustrative purposes, and the embodiments of the present application are not limited thereto. In other possible implementation manners, the second smallest, the second largest, the third smallest, or the third largest, etc. may also be used. In this embodiment, the "minimum or maximum" is used for illustrative purposes, but this embodiment is not limited thereto.

[0219] As mentioned above, the network device sends a MAC-CE signaling to the terminal device to activate the TCI-state. The MAC-CE can activate 8 TCI-states, and these 8 TCI-states are respectively in one-to-one correspondence with 8 TCI field values in ascending order of the index size. In this way, each TCI field value can correspond to one TCI-state. In the PDSCH transmission based on multiple TCI-states, the network device uses two TCI-states to send the PDSCH. Therefore, each TCI field value corresponds to two TCI-states. Similarly, the network device can activate multiple TCI-state groups through the MAC-CE signaling. Each TCI-state group includes one TCI-state or two TCI-states, and each TCI-state group corresponds to one TCI field value. Exemplarily, the correspondence between 8 TCI field values and 8 TCI-state groups is shown in Table 1 below.

[0220] Table 1 Correspondence Table between TCI Fields and TCI-State Groups

[0221] TCI field value (codepoint) TCI-state group 0 #2，#3 1 #4，#6 2 #2，#6 3 #4，#3 4 #2 5 #3 6 #4 7 #5

[0222] #2, #3, #6, etc. in Table 1 are all identifiers of the TCI-state, which are used to uniquely identify the TCI-state. #2 refers to the TCI-state identified by #2. For the convenience of description, #2, #3, and #6 will be used for subsequent description.

[0223] As shown in Table 1, assume that the TCI-state adopted by the first PDCCH is #2. If the first possible implementation mode of Mode 1 is adopted, then there are three TCI-state groups {#2, #3}, {#2, #6}, and {#2} that meet the conditions. If the TCI-state group corresponding to the minimum TCI field value is adopted, the terminal device can adopt {#2, #3}, that is, adopt TCI-state #2 and TCI-state #3 as the two first TCI-states. If the TCI-state group corresponding to the maximum TCI-state field value is adopted, the terminal device can adopt {#2}, that is, adopt TCI-state #2 as the only first TCI-state. If the second possible implementation mode of Mode 1 is adopted, then there are two TCI-state groups {#2, #3} and {#2, #6} that meet the conditions. If the TCI-state group corresponding to the minimum TCI field value is adopted, the terminal device can adopt {#2, #3}, that is, adopt TCI-state #2 and TCI-state #3 as the two first TCI-states. If the TCI-state group corresponding to the maximum TCI field value is adopted, the terminal device can adopt {#2, #6}, that is, adopt TCI-state #2 and TCI-state #6 as the two first TCI-states.

[0224] Mode 2: The terminal device uses a TCI-state activated by one CORESET (for example, the CORESET with the smallest or largest index) in one or more recently received CORESETs (such as the CORESET received in the most recent time slot) as one of the first TCI-states, and then determines the above first TCI-state based on this one of the first TCI-states.

[0225] One CORESET (for example, the CORESET with the smallest or largest index) in the above one or more recently received CORESETs (such as the CORESET received in the most recent time slot) can also be referred to as the "target CORESET". The recently received CORESET may be one or more. If the terminal device recently receives one CORESET, the target CORESET is this one CORESET. If the terminal device recently receives multiple CORESETs, the target CORESET can be the CORESET with the smallest or largest index among the multiple CORESETs. It should be understood that the above recently received CORESET (such as the CORESET received in the most recent time slot) can also be understood as the CORESET associated with the search space (search space) that is recently listened to (such as the search space listened to in the most recent time slot).

[0226] In a first possible implementation, the first TCI-state is a TCI-state included in a TCI-state group (e.g., a TCI-state group corresponding to the smallest or largest TCI field value) among one or more TCI-state groups that includes a TCI-state activated by one of the most recently received one or more CORESETs (e.g., the CORESET with the smallest or largest index).

[0227] In other words, there may be one TCI-state group that includes a TCI-state activated by the target CORESET, or there may be multiple TCI-state groups that include a TCI-state activated by the target CORESET. If there is one TCI-state group that includes a TCI-state activated by the target CORESET, the first TCI-state is the TCI-state included in this TCI-state group. If there are multiple TCI-state groups that include a TCI-state activated by the target CORESET, the first TCI-state is the TCI-state included in the TCI-state group with the smallest or largest corresponding TCI field value among these multiple TCI-state groups.

[0228] Exemplarily, the terminal device may use a TCI-state activated by a CSOREST (for example, the CSOREST with the smallest or largest index) in one or more recently received CORESETs (such as those received in the most recent time slot) as one of the first TCI-states. Then, the terminal device determines one or more TCI-state groups containing the above-mentioned one of the first TCI-states from at least one group of TCI-states activated for PDSCH transmission (each group of TCI-states corresponds to a TCI field value in the TCI field of the DCI). Finally, the terminal device selects one group of TCI-states from these TCI-state groups (for example, the group of TCI-states corresponding to the smallest or largest TCI field value), and uses all the TCI-states included in this group of TCI-states as the first TCI-states for the terminal device to receive the downlink signal. If the group of TCI-states determined by the terminal device contains one TCI-state, then the first TCI-state is one TCI-state, that is, the terminal device uses one first TCI-state to receive the downlink signal; if the group of TCI-states determined by the terminal device contains two TCI-states, then the first TCI-state is two TCI-states, that is, the terminal device uses two first TCI-states to receive the downlink signal.

[0229] In the second possible implementation manner, the first TCI-state is a TCI-state included in one group of TCI-states (for example, the group of TCI-states corresponding to the smallest or largest TCI field value) that contains a TCI-state activated by a CORESET (for example, the CORESET with the smallest or largest index) in one or more recently received CORESETs and contains two TCI-states.

[0230] In other words, there may be a TCI-state group containing two TCI-states that includes one TCI-state activated by the target CORESET, or there may be multiple TCI-state groups containing two TCI-states that include one TCI-state activated by the target CORESET. If there is a TCI-state group containing two TCI-states that includes one TCI-state activated by the target CORESET, then the first TCI-state is the TCI-state contained in this TCI-state group. If there are multiple TCI-state groups containing two TCI-states that include one TCI-state activated by the target CORESET, then the first TCI-state is the TCI-state contained in the TCI-state group with the smallest or largest corresponding TCI field value among these multiple TCI-state groups containing two TCI-states.

[0231] Exemplarily, the terminal device may use one TCI-state activated by one CORESET (e.g., the CORESET with the smallest or largest index) among one or more CORESETs received most recently (e.g., received in the most recent time slot) as one of the first TCI-states. Then, the terminal device determines one or more TCI-state groups that contain the above-mentioned one of the first TCI-states and contain two TCI-states from each of the activated TCI-state groups for PDSCH transmission (each TCI-state group corresponds to a TCI field value in the TCI field of the DCI). Finally, the terminal device selects one TCI-state group from these TCI-state groups (e.g., the TCI-state group with the smallest or largest corresponding TCI field value, or the TCI-state group with the smallest or largest index of the second TCI-state), and uses all the TCI-states contained in this TCI-state group as the first TCI-state. It should be understood that the above-mentioned second TCI-state refers to the other TCI-state in a TCI-state group containing two TCI-states, excluding the one TCI-state activated by one CORESET (e.g., the CORESET with the smallest or largest index) among one or more CORESETs received most recently (e.g., received in the most recent time slot). The method according to the embodiments of the present application can ensure that the determined TCI-state group of the terminal device must contain two TCI-states, so as to receive the downlink signal using two TCI-states.

[0232] In a third possible implementation, if there is no TCI-state group that contains a TCI-state activated by a CORESET (e.g., the CORESET with the smallest or largest index) in one of the most recently received one or more CORESETs, then the first TCI-state is a TCI-state activated by a CORESET (e.g., the CORESET with the smallest or largest index) in one of the most recently received CORESETs.

[0233] Exemplarily, the terminal device may first use the second possible implementation to determine two first TCI-states. If the two first TCI-states cannot be determined by using the above second possible implementation, that is, there is no TCI-state group that contains both a TCI-state activated by a CORESET (e.g., the CORESET with the smallest or largest index) in all the most recently received (e.g., received in the most recent time slot) CORESETs and two TCI-states, the terminal device may determine a unique first TCI-state. That is, the terminal device determines, from at least one TCI-state group that contains two TCI-states, a TCI-state group that contains the TCI-state activated by a CORESET (e.g., the CORESET with the smallest or largest index) in all the most recently received (e.g., received in the most recent time slot) CORESETs. If there is no such TCI-state group, the terminal device may determine the TCI-state activated by a CORESET (e.g., the CORESET with the smallest or largest index) in all the most recently received (e.g., received in the most recent time slot) CORESETs as the unique first TCI-state. Or rather, the terminal device determines, from one or more TCI-state groups that contain one TCI-state, a TCI-state group that contains the TCI-state activated by a CORESET (e.g., the CORESET with the smallest or largest index) in all the most recently received (e.g., received in the most recent time slot) CORESETs.

[0234] In the above Method 1 and Method 2, the terminal device determines a TCI-state group from the activated TCI-state groups for PDSCH transmission, which requires receiving an activation signaling first to activate the TCI-state for PDSCH transmission. That is, the terminal device will adopt Method 1 or Method 2 only when it has received the activation signaling and activated the TCI-state for PDSCH transmission. Otherwise, the terminal device can use a TCI-state adopted by the first PDCCH as the only first TCI-state; or, the terminal device can use the TCI-state activated by one CORESET (for example, the CORESET with the smallest or largest index) in all the recently received (such as received in the most recent time slot) CORESETs as the only first TCI-state.

[0235] For example, in combination with the above conditions, the specific implementation method of Method 1 can be expressed as: If the TCI-state for PDSCH transmission has been activated and a TCI-state adopted by the first PDCCH is included in one or more activated TCI-state groups (each TCI-state group corresponds to a field value of the TCI field in DCI), then all the TCI-states included in the TCI-state group with the smallest or largest corresponding TCI field value are used as the first TCI-state; otherwise, a TCI-state adopted by the first PDCCH is used as the first TCI-state.

[0236] For example, in combination with the above conditions, the specific implementation method of Method 2 can be expressed as: If the TCI-state for PDSCH transmission has been activated and the TCI-state activated by the CORESET with the smallest or largest index in all the recently received (such as received in the most recent time slot) CORESETs is included in one or more activated TCI-state groups (each TCI-state group corresponds to a field value of the TCI field in DCI), then all the TCI-states included in the TCI-state group with the smallest or largest corresponding TCI field value are used as the first TCI-state; otherwise, the TCI-state activated by the CORESET with the smallest or largest index in all the recently received (such as received in the most recent time slot) CORESETs is used as the first TCI-state.

[0237] For another example, the specific implementation method of Method 2 can be expressed as follows: If, after activating the TCI-state for PDSCH transmission, among all the CORESETs received most recently (such as those received in the most recent time slot), the TCI-state activated by the CORESET with the smallest or largest index is included in one or more activated TCI-state groups (each TCI-state group corresponds to a field value of the TCI field in the DCI), then all the TCI-states included in the TCI-state group with the smallest or largest corresponding TCI field value are used as the first TCI-state; otherwise, the TCI-state activated by the CORESET with the smallest or largest index among all the CORESETs received most recently (such as those received in the most recent time slot) is used as the first TCI-state.

[0238] It should be understood that the above "smallest or largest" is for illustrative purposes, and the embodiments of the present application are not limited thereto. In other possible implementation manners, the second smallest, the second largest, the third smallest, or the third largest, etc. may also be used. In this embodiment, the "smallest or largest" is used for illustrative purposes, but this embodiment is not limited thereto.

[0239] Method 3: The first TCI-state is the two TCI-states used in the most recent transmission of the second PDSCH, and the second PDSCH is transmitted using two TCI-states.

[0240] Alternatively, the first TCI-state is the two TCI-states used in the most recent transmission of the second PDSCH, the second PDSCH is transmitted using two TCI-states, and the two TCI-states are indicated by DCI.

[0241] Alternatively, the first TCI-state is the two TCI-states used in the most recent transmission of the second PDSCH, the second PDSCH is transmitted using two TCI-states, and the scheduling time interval is not less than a preset threshold.

[0242] For example, before this transmission, the network device has performed one or more transmissions of PDSCH to this terminal device. Among them, some PDSCHs are transmitted using a single TCI-state, and some PDSCHs are transmitted using two TCI-states. Then, the terminal device can use the two TCI-states of the PDSCH that was most recently transmitted using two TCI-states to receive and cache the downlink signal. That is, the above second PDSCH can be the PDSCH that was most recently transmitted using two TCI-states.

[0243] Optionally, the terminal device may also adopt the two TCI-states used by the PDSCH that was transmitted most recently using two TCI-states and whose scheduling time interval is not less than a preset threshold. For example, before this transmission, the network device has performed one or more PDSCH transmissions to this terminal device. Among them, some PDSCHs are transmitted using a single TCI-state, and some PDSCHs are transmitted using two TCI-states. Among the PDSCHs transmitted using two TCI-states, some PDSCHs have a scheduling time interval less than the preset threshold, and some PDSCHs have a scheduling time interval not less than the preset threshold. Then, the terminal device may adopt the TCI-states used by that PDSCH which was most recently transmitted using two TCI-states and whose scheduling time interval is not less than the preset threshold to receive and buffer the signal. The above second PDSCH may further be the PDSCH that was most recently transmitted using two TCI-states and whose scheduling time interval is not less than the preset threshold.

[0244] Optionally, when the scheduling time interval of the second PDSCH is not less than the preset threshold, the determination of the TCI-state of the second PDSCH may be further divided into the following two cases.

[0245] Case 1: The second PDSCH uses DCI format 1_1, and the tci-PresentInDci parameter in the CORESET corresponding to the first PDCCH is configured as "enabled". At this time, the two TCI-states of the second PDSCH are indicated by the TCI field in this DCI.

[0246] Case 2: The second PDSCH uses DCI format 1_0, or the parameter tci-PresentInDci in the CORESET corresponding to the first PDCCH is not configured. At this time, the two TCI-states of the second PDSCH are determined by other means. For example, the TCI-state of the PDCCH is used by default, and the specific method used is not limited here.

[0247] For the PDSCH corresponding to the above two cases, the terminal device may adopt the two TCI-states of the PDSCH in the most recent transmission in the PDSCH corresponding to Case 1, or may also adopt the two TCI-states of the PDSCH in the most recent transmission in the PDSCH corresponding to Case 2. Specifically, the terminal device may adopt the two TCI-states of the PDSCH that were transmitted most recently through two TCI-states and the two TCI-states are indicated by the TCI field in the DCI (i.e., determined by the method corresponding to the above Case 1), or may also adopt the two TCI-states of the PDSCH that were transmitted most recently through two TCI-states and the two TCI-states are determined by the method corresponding to the above Case 2.

[0248] Method 4: The first TCI-state is a TCI-state in one TCI-state group (for example, the TCI-state group corresponding to the smallest or largest TCI field value) among multiple TCI-state groups for PDSCH transmission, and the TCI-state group includes two TCI-states.

[0249] It should be understood that the above "smallest or largest" is an exemplary illustration, and the embodiments of the present application are not limited thereto. In other possible implementation manners, the second smallest, the second largest, the third smallest, or the third largest, etc. may also be adopted. In this embodiment, the "smallest or largest" is used for exemplary illustration, but this embodiment is not limited thereto.

[0250] In this method, the terminal device may adopt the TCI-state group corresponding to the smallest or largest TCI field value (codepoint) among the currently active multiple TCI-state groups for PDSCH transmission. In other words, the terminal device may adopt the TCI-state group corresponding to the smallest or largest TCI field value among at least one TCI-state group corresponding to all current TCI field values. Alternatively, the terminal device may adopt the one TCI-state group corresponding to the TCI field value of '000', or adopt the one TCI-state group corresponding to the TCI field value of '111'.

[0251] Exemplarily, in the TCI field and TCI-state correspondence table shown in Table 1, if the TCI-state with the smallest TCI field value is adopted, the two first TCI-states are #2 and #3 respectively; if the TCI-state with the largest TCI field value is adopted, the two first TCI-states are #5 and #7 respectively.

[0252] Method 5: The first TCI-state is two TCI-states used for transmitting the first PDCCH.

[0253] Since the network device sends the PDCCH to the terminal device, it can be sent by a single TRP (using a single TCI-state) or by multiple TRPs (using multiple TCI-states). When the network device uses two TCI-states to send the first PDCCH to the terminal device, the two first TCI-states can be the two TCI-states used for transmitting this first PDCCH.

[0254] Method 6: The first TCI-state is two currently active TCI-states in one CORESET (e.g., the CORESET with the smallest or largest index) among at least one control resource set CORESET listened to most recently (e.g., the most recent time slot).

[0255] Optionally, for any one or more of the above Methods 1 to 6, the following prerequisite conditions can be added: There exists a TCI-state that has been activated for PDSCH transmission, or a TCI-state that has been activated for PDSCH transmission in the active bandwidth part (active BWP), or a TCI-state that has been activated for PDSCH transmission in the active BWP of the serving cell.

[0256] Among them, the serving cell refers to the cell corresponding to the PDSCH transmission. That is, only when a TCI-state that has been activated for PDSCH transmission exists, will the terminal device use one of the above Methods 1 to 6 to determine the first TCI-state. Otherwise, the terminal device only uses a single TCI-state as the first TCI-state or the terminal device does not receive the PDSCH. Specifically, the terminal device can use the initially accessed SSB to determine this first TCI-state, that is, this first TCI-state and the SSB are QCL; or, the terminal device can use the TCI-state of the CORESET with the smallest or largest index in at least one configured or most recently listened CORESET as the first TCI-state; or, the terminal device can use the TCI-state of the DCI scheduling the PDSCH as the first TCI-state.

[0257] Exemplarily, in combination with the above conditions, the specific implementation method of Method 4 can be expressed as follows: If the TCI-state for PDSCH transmission has been activated (for example, the TCI-state for PDSCH transmission has been activated in the active BWP), and there is at least one TCI field value corresponding to two TCI-states, then the first TCI-state is the two TCI-states corresponding to the minimum or maximum field value among the TCI field values corresponding to the two TCI-states. It should be understood that this embodiment is only described by taking two TCI-states as an example, and these two TCI-states can also be replaced by a larger number of TCI-states, which is not limited here. If the TCI-state for PDSCH transmission has not been activated (for example, the TCI-state for PDSCH transmission has not been activated in the active BWP), then one TCI-state is used as the first TCI-state or the PDSCH is not received. For example, the initial access SSB is used to determine the first TCI-state, that is, the first TCI-state is QCL with the SSB; or, the TCI-state of the CORESET with the smallest or largest index among the configured or recently listened at least one CORESET is used as the first TCI-state; or, the TCI-state of the DCI scheduling the PDSCH is used as the first TCI-state. If the TCI-state for PDSCH transmission has been activated (for example, the TCI-state for PDSCH transmission has been activated in the active BWP), but each TCI field value corresponds to a single TCI-state, then one TCI-state is used as the first TCI-state. For example, the initial access SSB is used to determine the first TCI-state, that is, the first TCI-state is QCL with the SSB; or, the TCI-state of the CORESET with the smallest or largest index among the configured or recently listened at least one CORESET is used as the first TCI-state; or, the TCI-state of the DCI scheduling the PDSCH is used as the first TCI-state; or, the TCI-state with the smallest index among the configured / activated PDSCH TCI-states is used as the first TCI-state; or, the TCI-state corresponding to the minimum or maximum TCI field value among the activated PDSCH TCI-states is used as the first TCI-state.

[0258] It should be understood that the above "minimum or maximum" is for illustrative purposes, and the embodiments of the present application are not limited thereto. In other possible implementation manners, the terminal device may also adopt the second smallest, the second largest, the third smallest, or the third largest, etc. In this embodiment, the "minimum or maximum" is used for illustrative purposes, but this embodiment is not limited thereto.

[0259] In this manner, the terminal device may adopt the two TCI-states activated in the CORESET with the smallest or largest index among at least one CORESET listened to in the most recent time (for example, the most recent time slot). That is, within a previous period of time, the terminal device listened to the CORESET within one or more time slots, then the terminal device may select the two TCI-states activated in the CORESET with the smallest or largest index in the most recent time slot listened to.

[0260] It should be understood that there may be a situation where none of the TCI-state groups contains one of the above first TCI-states. Therefore, in a possible implementation manner, if none of the TCI-state groups contains one of the above first TCI-states, the terminal device may select the second TCI-state in the TCI-state group with the smallest TCI field value as the other first TCI-state. If the TCI-state group with the smallest TCI field value includes one TCI-state, the terminal device may adopt this TCI-state as the other first TCI-state.

[0261] In another possible implementation manner, if none of the TCI-state groups contains one of the above first TCI-states, the terminal device adopts the TCI-state with the smallest ID among all the activated TCI-states as the other first TCI-state; or, the terminal device adopts the second TCI-state with the smallest or largest ID among all the activated one or more TCI-state groups, where one TCI-state group includes two TCI-states, and the above second TCI-state refers to the second TCI-state in a TCI-state group. For example, two TCI-state groups {#2, #3} and {#4, #5} containing two TCI-states are activated, and these two TCI-state groups correspond to two second TCI-states #3 and #5. If the second TCI-state with the smallest ID is adopted, the terminal device may adopt TCI-state #3 as the other TCI-state.

[0262] In another possible implementation, if none of the TCI-state groups contains any one of the above-mentioned first TCI-states, the terminal device may use any one of the above methods three to six to determine two first TCI-states, that is, the execution conditions for determining two TCI-states in Method 1 or Method 2 are not met, and it falls back to other methods. For example, if in at least one currently active TCI-state group, there is no TCI-state group that contains any one of the above-mentioned first TCI-states, then the two first TCI-states are one TCI-state group among the multiple currently active TCI-state groups for PDSCH transmission (for example, the TCI-state group corresponding to the smallest or largest TCI field value).

[0263] The following provides a fallback mechanism, that is, when the terminal device cannot find two first TCI-states by the above methods (the methods for determining two TCI-states in Methods 1 to 6), the processing method of the terminal device. Specifically, when the two first TCI-states cannot be determined by the above methods, the terminal device may use one TCI-state as the only first TCI-state. For example, in the above Methods 1 and 2, when the terminal device cannot find a TCI-state group that meets the requirements, it may use one TCI-state as the only TCI-state. This TCI-state may be the TCI-state used by the first PDCCH, or the TCI-state activated by the CORESET with the smallest or largest index among all the recently received (such as the CORESET received in the most recent time slot) CORESETs.

[0264] For example, when using Method 1, a TCI-state used by the first PDCCH is TCI-state #8. According to Table 1, since none of the TCI-state groups contains TCI-state #8, TCI-state #8 is used as the only first TCI-state.

[0265] Another example, when using Method 2, a TCI-state activated by the CORESET with the smallest index among all the recently received (for example, the CORESET received in the most recent time slot) CORESETs is TCI-state #8. According to Table 1, since none of the TCI-state groups contains TCI-state #8, TCI-state #8 is used as the only first TCI-state.

[0266] In another possible implementation, after the terminal device determines two first TCI-states by using the foregoing method, it may determine whether to fallback to a transmission mode using a single first TCI-state based on whether these two first TCI-states can be received simultaneously. For example, after the terminal device determines two first TCI-states by using the foregoing Method 1 or Method 2 and finds that these two first TCI-states cannot be received simultaneously by it, the terminal device may use a single first TCI-state. Optionally, the single first TCI-state may be one of the two first TCI-states or the other first TCI-state. Optionally, the single first TCI-state may also be a TCI-state activated in the CORESET with the smallest or largest index among at least one recently received (for example, received in the most recent time slot) CORESET. Optionally, the single first TCI-state may also be the TCI-state used by the first PDCCH.

[0267] It should be understood that the above "two first TCI-states cannot be received simultaneously" means that the receiving beams corresponding to the two first TCI-states are different, and the terminal device has only one antenna panel or only one antenna panel is enabled. Therefore, the terminal device cannot simultaneously generate two different receiving beams for reception.

[0268] In addition, to ensure that the two TCI-states used can be received simultaneously, when activating the TCI-state of the PDSCH, it is necessary to ensure that: two TCI-states corresponding to the same TCI field value can be received simultaneously. That is, the above constraint is imposed when activating the TCI-state of the PDSCH.

[0269] As an optional embodiment, the network device may carry the purposes of the activated multiple TCI-states in the activation signaling of the TCI-state of the PDSCH (such as the MAC-CE signaling). For example, the network device may indicate that the activated multiple TCI-states are applicable to simultaneous transmission or time-division transmission. That is, the activated multiple TCI-state groups may be used for simultaneous transmission, may be used for time-division transmission, or may be both. The embodiments of the present application do not limit this. In this case, in the foregoing Method 1 to Method 6, the network device and the terminal device can only determine the two first TCI-states from the TCI-state group used for simultaneous transmission.

[0270] Exemplarily, for multi-TRP transmission with a single DCI, when the scheduling offset of the PDSCH is less than the threshold timeDurationForQCL, if the default TCI-state of R15 protocol (e.g., the activated TCI-state of the CORESET with the smallest ID in at least one CORESET corresponding to the search space listened in the most recent time slot after receiving the activation signaling of the TCI-state) is included in the TCI-state group corresponding to one or more TCI field values, the UE may assume that the DMRS ports of the PDSCH adopt the QCL parameters indicated by the TCI-state group corresponding to the TCI field value with the smallest TCI field value among one or more TCI field values including the default TCI-state of R15 protocol; otherwise, the UE may assume that the DMRS ports of the PDSCH adopt the QCL parameters indicated by the default TCI-state of R15 protocol.

[0271] As an optional embodiment, the method further includes: if the time interval is greater than or equal to the preset threshold, and the information of the TCI-state is not carried in the first PDCCH, determining a second TCI-state and receiving the first PDSCH using the second TCI-state.

[0272] After the terminal device completes the reception and processing of the first PDCCH, it can determine the information of the first PDSCH, such as the scheduled time interval, the time-frequency resources for transmitting the first PDSCH, the TCI-state used, etc. If the terminal device finds that the time interval between the scheduled first PDSCH and the first PDCCH is greater than or equal to the preset threshold according to the scheduling information in the first PDCCH, it means that there is no first PDSCH in the cached downlink signal. Therefore, the terminal device can discard the cached downlink signal and receive the first PDSCH according to the information of the time-frequency resources of the first PDSCH carried in the first PDCCH and the second TCI-state. That is, if the time interval between the first PDSCH and the first PDCCH is greater than or equal to the preset threshold, the terminal device can determine the TCI-state of the first PDSCH according to the first PDCCH. Specifically, it can be divided into the following two cases, and each case adopts the corresponding method.

[0273] Case 1: The first PDCCH carries TCI-state information. For example, the DCI type carried by the first PDCCH is DCI format 1_1, and the parameter tci-PresentInDci in the CORESET corresponding to the first PDCCH is configured as "enabled". At this time, the terminal device can use the two TCI-states indicated by the TCI-state information in the DCI as the two second TCI-states for transmitting the first PDSCH. The "TCI-state information in the DCI" can also be replaced with the "TCI-state information in the first PDCCH". That is to say, if the time interval between the first PDCCH and the first PDSCH it schedules is greater than a preset threshold, and the DCI type carried by the first PDCCH is DCI format 1_1 and the parameter tci-PresentInDci in the CORESET corresponding to the first PDCCH is configured as "enabled", then the two TCI-states indicated in the DCI are used as the two second TCI-states for transmitting the first PDSCH.

[0274] Case 2: The first PDCCH does not carry TCI-state information. For example, the DCI type carried by the first PDCCH is DCI format 1_0, or the parameter tci-PresentInDci is not configured in the CORESET corresponding to the first PDCCH. At this time, there is no TCI field in the DCI and the TCI-state information cannot be indicated. The terminal device can use any one of the following methods to determine the second TCI-state. That is to say, if the time interval between the DCI and the first PDSCH it schedules is greater than a preset threshold, and the DCI type is DCI format 1_0 or the parameter tci-PresentInDci is not configured in the CORESET corresponding to the first PDCCH, then the second TCI-state can be determined by any one of the following multiple methods:

[0275] Method 1: The terminal device uses one TCI-state used by the first PDCCH as one of the second TCI-states, and then determines the above-mentioned second TCI-state based on this one of the second TCI-states.

[0276] In the first possible implementation manner, the second TCI-state is a TCI-state included in one or more TCI-state groups (for example, the TCI-state group corresponding to the smallest or largest TCI field value) that include one TCI-state used by the first PDCCH.

[0277] In other words, there may be a TCI - state set that includes a TCI - state used by the first PDCCH, or there may be multiple TCI - state sets that include a TCI - state used by the first PDCCH. If there is a TCI - state set that includes a TCI - state used by the first PDCCH, then the second TCI - state is the TCI - state included in this TCI - state set. If there are multiple TCI - state sets that include a TCI - state used by the first PDCCH, then the second TCI - state is the TCI - state included in the TCI - state set with the smallest or largest corresponding TCI field value among these multiple TCI - state sets.

[0278] Exemplarily, the terminal device may use a TCI - state used by the first PDCCH as one of the second TCI - states. Then, the terminal device determines all TCI - state sets that include one of the above - mentioned second TCI - states from at least one activated TCI - state set for PDSCH transmission (each TCI - state set corresponds to a TCI field value in the DCI). Finally, the terminal device selects a TCI - state set from these TCI - state sets (for example, the TCI - state set with the smallest or largest corresponding TCI field value), and uses all TCI - states included in this TCI - state set as the second TCI - states for the terminal device to receive the downlink signal. If the TCI - state set determined by the terminal device includes one TCI - state, then the second TCI - state is one TCI - state, that is, the terminal device uses one second TCI - state to receive the downlink signal; if the TCI - state set determined by the terminal device includes two TCI - states, then the second TCI - state is two TCI - states, that is, the terminal device uses two second TCI - states to receive the downlink signal.

[0279] In the second possible implementation manner, the second TCI - state is the TCI - state included in one or more TCI - state sets that include a TCI - state used by the first PDCCH and include two TCI - states (the TCI - state set with the smallest or largest corresponding TCI field value).

[0280] In other words, there may be a TCI-state group containing two TCI-states that contains one TCI-state used by the first PDCCH, or there may be multiple TCI-state groups containing two TCI-states that contain one TCI-state used by the first PDCCH. If there is a TCI-state group containing two TCI-states that contains one TCI-state used by the first PDCCH, then the second TCI-state is the TCI-state contained in this TCI-state group. If there are multiple TCI-state groups containing two TCI-states that contain one TCI-state used by the first PDCCH, then the second TCI-state is the TCI-state contained in the TCI-state group with the smallest or largest corresponding TCI field value among these multiple TCI-state groups containing two TCI-states.

[0281] Exemplarily, the terminal device may use one TCI-state used by the first PDCCH as one of the second TCI-states. Then, the terminal device determines all TCI-state groups that contain one of the above second TCI-states and contain two TCI-states from at least one activated TCI-state group for PDSCH transmission (each TCI-state group corresponds to a TCI field value in the TCI field of the DCI). Finally, the terminal device selects one TCI-state group from these TCI-state groups (for example, the TCI-state group with the smallest or largest corresponding TCI field value, or the TCI-state group with the smallest or largest index of the second TCI-state), and uses all TCI-states contained in this TCI-state group as the second TCI-state. It should be understood that the above second TCI-state refers to the other TCI-state in a TCI-state group that includes two TCI-states, except for one TCI-state used by the first PDCCH. The method according to the embodiments of the present application can ensure that the determined TCI-state group of the terminal device must contain two TCI-states, so as to receive the downlink signal using two TCI-states.

[0282] In a third possible implementation manner, if there is no one or more TCI-state groups that contain one TCI-state used by the first PDCCH, then the second TCI-state is the one TCI-state used by the first PDCCH.

[0283] Exemplarily, the terminal device may first adopt the second possible implementation manner described above to determine two second TCI-states. If the two second TCI-states cannot be determined by adopting the second possible implementation manner described above, that is, there is no TCI-state group that contains one TCI-state adopted by the first PDCCH and also contains two TCI-states, the terminal device may determine a unique second TCI-state. That is, the terminal device determines, from at least one TCI-state group containing two TCI-states, a TCI-state group that contains one TCI-state adopted by the first PDCCH. If there is no such TCI-state group, the terminal device may determine the one TCI-state adopted by the first PDCCH as the unique second TCI-state, or in other words, determine, from at least one TCI-state group containing one TCI-state, a TCI-state group that contains one TCI-state adopted by the first PDCCH.

[0284] Method 2: The terminal device uses one TCI-state activated by one CORESET (for example, the CORESET with the smallest or largest index) in one or more recently received CORESETs (such as the CORESET received in the most recent time slot) as one of the second TCI-states, and then determines the second TCI-state based on this one second TCI-state.

[0285] One CORESET (for example, the CORESET with the smallest or largest index) in the one or more recently received CORESETs (such as the CORESET received in the most recent time slot) described above may also be referred to as the "target CORESET". The number of recently received CORESETs may be one or more. If the terminal device recently receives one CORESET, the target CORESET is this one CORESET. If the terminal device recently receives multiple CORESETs, the target CORESET may be the CORESET with the smallest or largest index among the multiple CORESETs. It should be understood that the recently received CORESET (such as the CORESET received in the most recent time slot) described above may also be understood as the CORESET associated with the search space (search space) that is recently listened to (such as the search space listened to in the most recent time slot).

[0286] In a first possible implementation, the second TCI-state is one of one or more TCI-state groups that includes a TCI-state activated by one CORESET among one or more recently received CORESETS (e.g., the CORESET with the smallest or largest index), and the TCI-state included in the TCI-state group (e.g., the TCI-state group with the smallest or largest corresponding TCI field value).

[0287] In other words, there may be one TCI-state group that includes a TCI-state activated by the target CORESET, or there may be multiple TCI-state groups that include a TCI-state activated by the target CORESET. If there is one TCI-state group that includes a TCI-state activated by the target CORESET, the second TCI-state is the TCI-state included in this TCI-state group. If there are multiple TCI-state groups that include a TCI-state activated by the target CORESET, the second TCI-state is the TCI-state included in the TCI-state group with the smallest or largest corresponding TCI field value among these multiple TCI-state groups.

[0288] Exemplarily, the terminal device may use a TCI-state activated by one CSOREST (e.g., the CSOREST with the smallest or largest index) in one or more recently received (e.g., received in the most recent time slot) CORESETs as one of the second TCI-states. Then, the terminal device determines one or more TCI-state groups containing the above-mentioned one of the second TCI-states from at least one group of TCI-states activated for PDSCH transmission (each group of TCI-states corresponds to a TCI field value of the TCI field in the DCI). Finally, the terminal device selects one group of TCI-states (e.g., the group of TCI-states corresponding to the smallest or largest TCI field value) from these TCI-state groups, and uses all the TCI-states included in this group of TCI-states as the second TCI-states for the terminal device to receive the downlink signal. If the group of TCI-states determined by the terminal device contains one TCI-state, then the second TCI-state is one TCI-state, that is, the terminal device uses one second TCI-state to receive the downlink signal; if the group of TCI-states determined by the terminal device contains two TCI-states, then the second TCI-state is two TCI-states, that is, the terminal device uses two second TCI-states to receive the downlink signal.

[0289] In a second possible implementation manner, the second TCI-state is a TCI-state included in one group of TCI-states (e.g., the group of TCI-states corresponding to the smallest or largest TCI field value) that contains a TCI-state activated by one CORESET (e.g., the CORESET with the smallest or largest index) in one or more recently received CORESETs and contains two TCI-states.

[0290] In other words, there may be a TCI-state group containing two TCI-states that includes one TCI-state activated by the target CORESET, or there may be multiple TCI-state groups containing two TCI-states that include one TCI-state activated by the target CORESET. If there is a TCI-state group containing two TCI-states that includes one TCI-state activated by the target CORESET, then the second TCI-state is the TCI-state contained in this TCI-state group. If there are multiple TCI-state groups containing two TCI-states that include one TCI-state activated by the target CORESET, then the second TCI-state is the TCI-state contained in the TCI-state group with the smallest or largest corresponding TCI field value among these multiple TCI-state groups containing two TCI-states.

[0291] Exemplarily, the terminal device may use one TCI-state activated by one CORESET (e.g., the CORESET with the smallest or largest index) among one or more recently received CORESETs (such as the one received in the most recent time slot) as one of the second TCI-states. Then, the terminal device determines one or more TCI-state groups that contain the above-mentioned one of the second TCI-states and contain two TCI-states from each TCI-state group activated for PDSCH transmission (each TCI-state group corresponds to a TCI field value in the TCI field of the DCI). Finally, the terminal device selects one TCI-state group from these TCI-state groups (e.g., the TCI-state group with the smallest or largest corresponding TCI field value, or the TCI-state group with the smallest or largest index of the second TCI-state), and uses all the TCI-states contained in this TCI-state group as the second TCI-state. It should be understood that the above-mentioned second TCI-state refers to the other TCI-state in a TCI-state group containing two TCI-states, excluding the one TCI-state activated by one CORESET (e.g., the CORESET with the smallest or largest index) among one or more recently received CORESETs (such as the one received in the most recent time slot). The method of the embodiment of the present application can ensure that the determined TCI-state group of the terminal device must contain two TCI-states, so as to receive the downlink signal using two TCI-states.

[0292] In a third possible implementation manner, if there is no TCI-state group that includes a TCI-state activated by one CORESET (e.g., the CORESET with the smallest or largest index) among one or more recently received CORESETs, the second TCI-state is a TCI-state activated by one CORESET (e.g., the CORESET with the smallest or largest index) among the recently received CORESETs.

[0293] Exemplarily, the terminal device may first adopt the second possible implementation manner to determine two second TCI-states. If the two second TCI-states cannot be determined by adopting the above second possible implementation manner, that is, there is no TCI-state group that includes both a TCI-state activated by one CORESET (e.g., the CORESET with the smallest or largest index) among all the recently received (such as those received in the most recent time slot) CORESETs and two TCI-states, the terminal device may determine a unique second TCI-state. That is, the terminal device determines, from at least one TCI-state group that includes two TCI-states, a TCI-state group that includes the TCI-state activated by one CORESET (e.g., the CORESET with the smallest or largest index) among all the recently received (such as those received in the most recent time slot) CORESETs. If there is no such TCI-state group, the terminal device may determine the TCI-state activated by one CORESET (e.g., the CORESET with the smallest or largest index) among all the recently received (such as those received in the most recent time slot) CORESETs as the unique second TCI-state. Or rather, the terminal device determines, from one or more TCI-state groups that include one TCI-state, a TCI-state group that includes the TCI-state activated by one CORESET (e.g., the CORESET with the smallest or largest index) among all the recently received (such as those received in the most recent time slot) CORESETs.

[0294] In the above Method 1 and Method 2, the terminal device determines one TCI-state group from the activated TCI-state groups for PDSCH transmission, which requires receiving an activation signaling first to activate the TCI-state for DPSCH transmission. That is, the terminal device will only adopt Method 1 or Method 2 above on the premise that it has received the activation signaling and activated the TCI-state for PDSCH transmission. Otherwise, the terminal device can use a TCI-state adopted by the first PDCCH as the only second TCI-state; or, the terminal device can use the TCI-state activated by one CORESET (for example, the CORESET with the smallest or largest index) among all the CORESETs received recently (such as received in the most recent time slot) as the only second TCI-state.

[0295] For example, in combination with the above conditions, the specific implementation method of Method 1 can be expressed as: If the TCI-state for PDSCH transmission has been activated and a TCI-state adopted by the first PDCCH is included in one or more activated TCI-state groups (each TCI-state group corresponds to a field value of the TCI field in DCI), then all the TCI-states included in the TCI-state group with the smallest or largest corresponding TCI field value are used as the second TCI-state; otherwise, a TCI-state adopted by the first PDCCH is used as the second TCI-state.

[0296] For example, in combination with the above conditions, the specific implementation method of Method 2 can be expressed as: If the TCI-state for PDSCH transmission has been activated and the TCI-state activated by the CORESET with the smallest or largest index among all the CORESETs received recently (such as received in the most recent time slot) is included in one or more activated TCI-state groups (each TCI-state group corresponds to a field value of the TCI field in DCI), then all the TCI-states included in the TCI-state group with the smallest or largest corresponding TCI field value are used as the second TCI-state; otherwise, the TCI-state activated by the CORESET with the smallest or largest index among all the CORESETs received recently (such as received in the most recent time slot) is used as the second TCI-state.

[0297] For another example, the specific implementation method of Method 2 can be expressed as follows: If, after activating the TCI-state for PDSCH transmission, among all the CORESETs received most recently (e.g., received in the most recent time slot), the TCI-state activated by the CORESET with the smallest or largest index is included in one or more activated TCI-state groups (each TCI-state group corresponds to a field value of the TCI field in the DCI), then all the TCI-states included in the TCI-state group with the smallest or largest corresponding TCI field value are used as the second TCI-state; otherwise, the TCI-state activated by the CORESET with the smallest or largest index among all the CORESETs received most recently (e.g., received in the most recent time slot) is used as the second TCI-state.

[0298] Method 3: The second TCI-state is the two TCI-states used for the most recent transmission of the second PDSCH, and the second PDSCH is transmitted using two TCI-states.

[0299] Alternatively, the second TCI-state is the two TCI-states used for the most recent transmission of the second PDSCH, the second PDSCH is transmitted using two TCI-states, and the two TCI-states are indicated by DCI.

[0300] Alternatively, the second TCI-state is the two TCI-states used for the most recent transmission of the second PDSCH, the second PDSCH is transmitted using two TCI-states, and the scheduling time interval is not less than a preset threshold value.

[0301] Method 4: The second TCI-state is a TCI-state in a TCI-state group (e.g., the TCI-state group corresponding to the smallest or largest TCI field value) among multiple TCI-state groups for PDSCH transmission, and the TCI-state group includes two TCI-states.

[0302] Method 5: The second TCI-state is the two TCI-states used for transmitting the first PDCCH.

[0303] Method 6: The second TCI-state is the two currently activated TCI-states in a CORESET (e.g., the CORESET with the smallest or largest index) in the control resource set CORESET listened to most recently (e.g., in the most recent time slot).

[0304] The above methods 1 to 6 for determining the second TCI-state are the same as methods 1 to 6 for determining the first TCI-state, and will not be elaborated here.

[0305] Optionally, for any one or more of the above methods 1 to 6, the following prerequisite conditions may be added: there is a TCI-state that has been activated for PDSCH transmission, or there is a TCI-state that has been activated for PDSCH transmission in the active bandwidth part (active BWP), or there is a TCI-state that has been activated for PDSCH transmission in the active BWP of the serving cell.

[0306] Among them, the serving cell refers to the cell corresponding to PDSCH transmission. That is to say, only when a TCI-state for PDSCH transmission has been activated, the terminal device will use one of the above methods 1 to 6 to determine the second TCI-state. Otherwise, the terminal device only uses one TCI-state as the second TCI-state or the terminal device does not receive PDSCH. Specifically, the terminal device may use the initially accessed SSB to determine the second TCI-state, that is, the second TCI-state is QCL with the SSB; or, the terminal device may use the TCI-state of the CORESET with the smallest or largest index in at least one configured or recently listened CORESET as the second TCI-state; or, the terminal device may use the TCI-state of the DCI scheduling the PDSCH as the second TCI-state.

[0307] Exemplarily, in combination with the above conditions, the specific implementation method of Method 4 can be expressed as follows: If the TCI-state for PDSCH transmission has been activated (for example, the TCI-state for PDSCH transmission has been activated in the active BWP), and there is at least one TCI field value corresponding to two TCI-states, then the second TCI-state is the two TCI-states corresponding to the minimum or maximum field value among the TCI field values corresponding to the two TCI-states. It should be understood that this embodiment is only described by taking two TCI-states as an example, and these two TCI-states can also be replaced by a larger number of TCI-states, which is not limited here. If the TCI-state for PDSCH transmission has not been activated (for example, the TCI-state for PDSCH transmission has not been activated in the active BWP), then one TCI-state is used as the second TCI-state or PDSCH is not received. For example, the initial access SSB is used to determine the second TCI-state, that is, the second TCI-state is QCL with the SSB; or, the TCI-state of the CORESET with the smallest or largest index among the configured or recently listened at least one CORESET is used as the second TCI-state; or, the TCI-state of the DCI scheduling the PDSCH is used as the second TCI-state. If the TCI-state for PDSCH transmission has been activated (for example, the TCI-state for PDSCH transmission has been activated in the active BWP), but each TCI field value corresponds to a single TCI-state, then one TCI-state is used as the second TCI-state. For example, the initial access SSB is used to determine the second TCI-state, that is, the second TCI-state is QCL with the SSB; or, the TCI-state of the CORESET with the smallest or largest index among the configured or recently listened at least one CORESET is used as the second TCI-state; or, the TCI-state of the DCI scheduling the PDSCH is used as the second TCI-state; or, the TCI-state with the smallest index among the configured / activated PDSCH TCI-states is used as the second TCI-state; or, the TCI-state corresponding to the minimum or maximum TCI field value among the activated PDSCH TCI-states is used as the second TCI-state.

[0308] Similarly, it is possible that none of the TCI-state groups contains any one of the above-mentioned second TCI-states. Therefore, in one possible implementation, if none of the TCI-state groups contains any one of the above-mentioned second TCI-states, the terminal device may select the second TCI-state in the TCI-state group with the smallest TCI field value as the other second TCI-state. If the TCI-state group with the smallest TCI field value includes one TCI-state, the terminal device may use this TCI-state as the other second TCI-state.

[0309] In another possible implementation, if none of the TCI-state groups contains any one of the above-mentioned second TCI-states, the terminal device uses the TCI-state with the smallest ID among all the activated TCI-states as the other second TCI-state; or, the terminal device uses the second TCI-state with the smallest or largest ID among all the activated one or more TCI-state groups, where one TCI-state group includes two TCI-states, and the above-mentioned second TCI-state refers to the second TCI-state in a TCI-state group. For example, two TCI-state groups {#2, #3} and {#4, #5} containing two TCI-states are activated, and these two TCI-state groups correspond to two second TCI-states #3 and #5. If the second TCI-state with the smallest ID is used, the terminal device may use TCI-state #3 as the other TCI-state.

[0310] In another possible implementation, if none of the TCI-state groups contains any one of the above-mentioned second TCI-states, the terminal device may use any one of the above-mentioned methods 3 to 6 to determine the two second TCI-states, that is, if the execution conditions for determining the two TCI-states in method 1 or method 2 are not met, it falls back to other methods. For example, if in at least one of the currently activated TCI-state groups, there is no TCI-state group containing any one of the above-mentioned second TCI-states, the two second TCI-states are one of the TCI-state groups in the multiple groups of TCI-states currently activated for PDSCH transmission (for example, the TCI-state group corresponding to the smallest or largest TCI field value).

[0311] A fallback mechanism is provided below, which is a processing method for the terminal device when two second TCI-states cannot be found by the above methods (the methods for determining two TCI-states in Manner 1 to Manner 6). Specifically, when two second TCI-states cannot be determined by the above methods, the terminal device may use one TCI-state as the only TCI-state. For example, in Manner 1 and Manner 2 above, when the terminal device cannot find a TCI-state group that meets the requirements, one TCI-state may be used as the only TCI-state. This TCI-state may be the TCI-state used by the first PDCCH, or the TCI-state activated by the CORESET with the smallest or largest index among all the recently received (such as the one received in the most recent time slot) CORESETs.

[0312] For example, when using Manner 1, a TCI-state used by the first PDCCH is TCI-state#8. According to Table 1, since there is no TCI-state group that contains TCI-state#8, TCI-state#8 is used as the only second TCI-state.

[0313] Another example is that when using Manner 2, a TCI-state activated by the CORESET with the smallest index among all the recently received (for example, the one received in the most recent time slot) CORESETs is TCI-state#8. According to Table 1, since there is no TCI-state group that contains TCI-state#8, TCI-state#8 is used as the only second TCI-state.

[0314] In another possible implementation, after the terminal device determines two second TCI-states by using the above method, it can determine whether to fallback to the transmission mode using a single second TCI-state based on whether these two second TCI-states can be received simultaneously. For example, after the terminal device determines two second TCI-states by using the above method 1 or method 2, and finds that these two second TCI-states cannot be received by it simultaneously, then the terminal device can use a single second TCI-state. Optionally, the single second TCI-state can be one of the above two second TCI-states, or the other second TCI-state. Optionally, the single second TCI-state can also be the TCI-state activated in the CORESET with the smallest or largest index among at least one CORESET received recently (for example, received in the most recent time slot). Optionally, the single second TCI-state can also be the TCI-state used by the first PDCCH.

[0315] The specific determination method of the single second TCI-state is the same as that of the single first TCI-state, and will not be described in detail here.

[0316] After determining one second TCI-state or two second TCI-states for transmitting the first PDSCH by the above method, the terminal device can receive the first PDSCH according to this one TCI-state or two TCI-states. Specifically, the terminal device can determine the information of the transmission beam according to the reference signal included in this one TCI-state or two TCI-states, so as to determine the corresponding receiving beam, and use the receiving beam to receive the first PDSCH transmitted on this one transmission beam or two transmission beams.

[0317] In the above method, the preset threshold value can be used for both high-frequency transmission and low-frequency transmission, that is, transmission is carried out using frequency range 2 (FR2) and frequency range 1 (FR1). In this case, regardless of whether the transmission is carried out in FR1 or FR2, the above method can be used to determine the TCI-state of the first PDSCH. That is, when the time interval between the first PDCCH and the first PDSCH is less than the preset threshold value, the terminal device can receive the PDSCH using the first TCI-state determined by the above method; when the time interval between the first PDCCH and the first PDSCH is greater than or equal to the preset threshold value, and the DCI carried by the first PDCCH does not contain the information of the TCI-state, the terminal device can receive the PDSCH using the second TCI-state determined by the above method; when the time interval between the first PDCCH and the first PDSCH is greater than or equal to the preset threshold value, and the DCI carried by the first PDCCH contains the information of the TCI-state, the terminal device can receive the PDSCH using the TCI-state indicated by the first PDCCH.

[0318] In the above method, the preset threshold value can be only used for high-frequency transmission, that is, transmission is carried out using frequency FR2 or a TCI-state including QCL-type D is configured. In this case, the above method is used to determine the TCI-state of the first PDSCH. That is, when the time interval between the first PDCCH and the first PDSCH is less than the preset threshold value, the terminal device can receive the PDSCH using the first TCI-state determined by the above method; when the time interval between the first PDCCH and the first PDSCH is greater than or equal to the preset threshold value, and the DCI does not contain the information of the TCI-state, the terminal device can receive the PDSCH using the second TCI-state determined by the above method; when the time interval between the first PDCCH and the first PDSCH is greater than or equal to the preset threshold value, and the DCI contains the information of the TCI-state, the terminal device can receive the PDSCH using the TCI-state indicated by the first PDCCH. When transmitting using FR1, since it is not necessary to distinguish whether the time interval between the first PDCCH and the first PDSCH is less than the preset threshold value, the following method can be used. That is, when the DCI carried by the first PDCCH does not contain the information of the TCI-state, the terminal device can receive the PDSCH using the second TCI-state determined by the above method; when the DCI carried by the first PDCCH contains the information of the TCI-state, the terminal device can receive the PDSCH using the TCI-state indicated by the first PDCCH.

[0319] It should be understood that the transmission of the PDSCH uses the FR2 frequency, which is equivalent to the serving cell scheduling the PDSCH being configured with a TCI-state including quasi co-location QCL-TypeD information. This application does not limit these two descriptions.

[0320] It can be understood that the inclusion of TCI-state in the above DCI means that the DCI format is DCI 1_1, and the value of the tci-PresentInDCI parameter in the CORESET corresponding to the first PDCCH is configured to enabled; the non-inclusion of TCI-state in the DCI can be understood as the DCI format being DCI 1_0, or the tci-PresentInDCI parameter in the CORESET corresponding to the first PDCCH not being configured.

[0321] It should be understood that the above tci-PresentInDci is a configuration parameter indicating whether the DCI carries the information of TCI-state. This application does not limit the name of this parameter to tci-PresentInDci. The parameter tci-PresentInDci being configured as "enabled" means that the DCI carries the information of TCI-state. The condition "the parameter tci-PresentInDci is configured as 'enabled'" can be replaced with other forms of conditions as long as these conditions can indicate that the DCI carries the information of TCI-state. Similarly, the condition "the parameter tci-PresentInDci is not configured" can be replaced with other forms of conditions as long as these conditions can indicate that the DCI does not carry the information of TCI-state. Embodiments of this application do not limit this.

[0322] It should also be understood that the above DCI type being DCI format 1_1 means that there is a TCI field in the DCI. The condition "the DCI type is DCI format 1_1" can also be replaced with other forms of conditions as long as these conditions can indicate that there is a TCI field in the DCI. Similarly, the condition "the DCI type is DCI format 1_0" can also be replaced with other forms of conditions as long as these conditions can indicate that there is no TCI field in the DCI.

[0323] As an optional embodiment, the method further includes: receiving a first signaling, where the first signaling is used to activate one or more TCI-states for a CORESET, and the first signaling includes one or more of the following fields: a field for indicating the number of activated TCI-states, a field for indicating whether the number of activated TCI-states is single or multiple.

[0324] In the embodiments of the present application, since data transmission is based on multiple TCI-states, multiple TCI-states can be used to transmit PDCCH. Then, each CORESET can activate one TCI-state or multiple TCI-states. The network device can send a first signaling to the terminal device to activate one TCI-state or multiple TCI-states for a CORESET. The first signaling may include a field for indicating the number of activated TCI-states (which may be simply referred to as the quantity indication field), and / or a field for indicating whether the number of activated TCI-states is single or multiple. The first signaling may be a MAC-CE signaling, an RRC signaling, or a DCI signaling, and the embodiments of the present application do not limit this. The above first signaling may be sent by the network device to the terminal device before sending the first PDCCH.

[0325] Figure 5 FIG. shows a schematic format diagram of the first signaling in the embodiments of the present application. As Figure 5 shown, the first signaling includes the following fields:

[0326] Serving cell ID field: used to indicate the identifier of the serving cell.

[0327] Quantity indication field: a field for indicating the number of activated TCI-states, or a field for indicating whether the number of activated TCI-states is single or multiple. In other words, this field can be used to indicate the number of TCI-states activated by the first signaling, or the TCI-state quantity indication field can be used to indicate whether the first signaling activates a single TCI-state or multiple TCI-states. For example, the quantity indication field is 1 bit, the field value of 0 indicates activating a single TCI-state, and the field value of 1 indicates activating multiple TCI-states. Optionally, the quantity indication field may be located before the serving cell ID field or after the serving cell ID field, and the embodiments of the present application do not limit this.

[0328] CORESET ID field: used to indicate the identifier of the CORESET.

[0329] TCI-state ID field: used to indicate the identifier of the TCI-state.

[0330] Wherein, R represents a reserved bit, and Oct represents an octet.

[0331] In the method for data transmission according to the embodiments of the present application, the terminal device can determine the TCI-state used by the network device for data transmission in various ways, so that the terminal device determines the receiving beam according to the TCI-state and receives the data sent by the network device, thereby improving the efficiency of data transmission.

[0332] Figure 6 The figure shows a schematic diagram of another data transmission scenario according to the embodiments of the present application. This data transmission scenario is a multi-TRP transmission scenario based on multiple PDCCHs, that is, the network device sends PDSCH to the terminal device through multiple TRPs, where the PDSCH sent by each TRP is an independent PDSCH. Each TRP uses a TCI-state to send the PDSCH. Therefore, the terminal device can determine multiple TCI-states to correctly receive the PDSCH corresponding to each TCI-state respectively. For ease of description, Figure 6 two TRPs are shown in the figure (that is, the terminal device can determine two TCI-states). Specifically, TRP 1 sends PDCCH 1 to the terminal device for scheduling PDSCH 1 transmitted by TRP 1, and TRP 2 sends PDCCH 2 to the terminal device for scheduling PDSCH 2 transmitted by TRP 2. TRP 1 sends PDSCH 1 to the terminal device using TCI-state #1, and TRP 2 sends PDSCH 2 to the terminal device using TCI-state #2. PDSCH 1 and PDSCH 2 are two independent PDSCHs. The terminal device determines TCI-state #1 and TCI-state #2 to correctly receive PDSCH 1 and PDSCH 2.

[0333] For Figure 6 the scenario shown, Figure 7 The figure shows a schematic flowchart of the data transmission method 700 provided by the embodiments of the present application. The method 700 includes:

[0334] S710, the network device sends N physical downlink control channels PDCCH to the terminal device. Correspondingly, the terminal device receives N physical downlink control channels PDCCH from the network device. The N PDCCHs are respectively used to schedule N physical downlink shared channels PDSCH, and N is an integer greater than 1. Each of the N PDCCHs includes the transmission parameters of the PDSCH sent by its corresponding TRP, such as the time-frequency resources for transmitting the PDSCH, the TCI-state of the PDSCH, etc. In Figure 6 the scenario shown in the figure, N = 2. For ease of understanding, subsequent descriptions will be made with N = 2 as an example.

[0335] Exemplarily, the network device may send two PDCCHs for scheduling two PDSCHs to the terminal device through two TRPs. As described above, when the network device sends the two PDSCHs, it may determine the time interval between each PDCCH and the PDSCH it schedules respectively. If the time interval between a PDCCH and the PDSCH it schedules is less than a preset threshold, the network device will send the PDSCH using the default TCI-state. If the time interval between a PDCCH and the PDSCH it schedules is greater than or equal to the preset threshold, the network device may send the PDSCH using the default TCI-state, or may also send the PDSCH using other TCI-states, and carry the information indicating the TCI-state in the PDCCH to inform the terminal device.

[0336] In S720, the network device sends a downlink signal to the terminal device, and the terminal device receives the downlink signal from the network device using two transmission configuration indication states (TCI-states).

[0337] For any PDCCH among the two PDCCHs, before the terminal device finishes processing the PDCCH, since it is not certain whether the network device has sent the PDSCH scheduled by the PDCCH during the reception of the PDCCH, in order not to miss the PDSCH, the terminal device uses the receiving beam corresponding to the first TCI-state (which can also be called the default TCI-state) to receive all the downlink signals for a period of time with a duration of the preset threshold starting from the symbol where the PDCCH is located, and caches them until the reception and processing of the PDCCH are completed.

[0338] In S730, the terminal device obtains the time interval between the first PDCCH among the two PDCCHs and the first PDSCH corresponding to the first PDCCH.

[0339] The time interval between the first PDCCH and the first PDSCH in the embodiments of this application may also be referred to as the scheduling time interval of the first PDSCH, or the scheduling offset of the first PDSCH, or other names.

[0340] In S730, if the time interval is less than the preset threshold, the terminal device obtains the first PDSCH from the downlink signals received using the first TCI-state corresponding to the first PDCCH among the two TCI-states.

[0341] After the terminal device completes the reception and processing of the first PDCCH, it can determine the time interval between the first PDSCH scheduled by the first PDCCH and the first PDCCH. If the time interval is less than a preset threshold, the terminal device can determine that the first PDSCH is included in the cached downlink signal, and obtain the first PDSCH from the cached downlink signal according to the parameters indicated by the PDCCH (such as the time-frequency resource information of the PDSCH).

[0342] In the embodiments of the present application, the PDSCHs sent by two TRPs can be regarded as two PDSCHs. Each PDSCH corresponds to a TCI-state. Therefore, the terminal device can respectively determine the default TCI-state of each PDSCH. Therefore, the subsequent content of the embodiments of the present application is described for a single PDCCH and the single PDSCH scheduled by the PDCCH, that is, the method for determining the TCI-state of a single PDSCH is discussed. The method for determining the TCI-state of other PDSCHs is the same as the method for determining the TCI-state of this single PDSCH.

[0343] It should also be understood that the preset threshold (timeDurationForQCL) represents the time required for the terminal device to receive and process the PDCCH and prepare the receiving beam of the PDSCH (that is, it may take a certain amount of time to switch to the receiving beam of the PDSCH). The present application does not limit the name of this preset threshold to timeDurationForQCL. The time interval between the first PDCCH and the second PDSCH being less than the preset threshold means that the transmission time of the first PDSCH is before the completion of the reception of the first PDCCH. The condition "the time interval between the first PDCCH and the first PDSCH scheduled by it is less than the preset threshold" can also be replaced with other forms of conditions, as long as the condition can indicate that the transmission time of the first PDSCH is before the completion of the reception of the first PDCCH. Similarly, the condition "the time interval between the first PDCCH and the first PDSCH scheduled by it is not less than the preset threshold" can also be replaced with other forms of conditions, as long as the condition can indicate that the transmission time of the first PDSCH is after the completion of the reception of the first PDCCH.

[0344] The above condition "the time interval between the first PDCCH and the first PDSCH it schedules is less than a preset threshold" can also be replaced with "the time interval between the first PDCCH and the first PDSCH it schedules is less than or equal to a preset threshold". Correspondingly, the condition "the time interval between the first PDCCH and the first PDSCH it schedules is greater than or equal to a preset threshold" can also be replaced with "the time interval between the first PDCCH and the first PDSCH it schedules is greater than a preset threshold". That is, the "equal" case can be grouped together with the "less than" case or with the "greater than" case. The embodiments of the present application do not make any limitations in this regard.

[0345] As an optional embodiment, the first TCI-state is the currently active TCI-state in a CORESET (e.g., the CORESET with the smallest or largest index) in the first control resource set CORESET group received most recently (e.g., in the most recent time slot), where the first CORESET group is a CORESET group composed of CORESETs having the same index as the CORESET corresponding to the first PDCCH. Here, the same index can also be referred to as the same grouping index (or the same grouping index value), which is used to group the CORESETs.

[0346] Exemplarily, for PDSCH transmission based on multiple DCIs, for each PDSCH, if its scheduling offset is less than the threshold timeDurationForQCL, the UE may assume that the DMRS ports of the PDSCH adopt the QCL parameters of the TCI-state activated by the CORESET with the smallest ID in one or more CORESETs corresponding to the search space listened in the most recent time slot, where the one or more CORESETs have the same HigherLayerIndexPerCORESET value.

[0347] It should be understood that the above "smallest or largest" is for illustrative purposes only, and the embodiments of the present application are not limited thereto. In other possible implementation manners, the second smallest, the second largest, the third smallest, or the third largest, etc. may also be used. In this embodiment, the "smallest or largest" is used for illustrative purposes, but this embodiment is not limited thereto.

[0348] When the time interval between the first PDSCH and the first PDCCH is less than a preset threshold, the above-mentioned first TCI-state may be the TCI-state currently activated by the CORESET with the smallest or largest index in the CORESET group to which the CORESET corresponding to the first PDCCH belongs. The above-mentioned CORESET group refers to the CORESETs associated with the same index (which can also be called a specific index value). It should be understood that each CORESET is associated with a specific index value (such as 0 or 1). The CORESETs associated with the same index value can be regarded as a group. For example, all the CORESETs associated with the index value 0 can be regarded as a group of CORESETs, and all the CORESETs associated with the index value 1 can be regarded as another group of CORESETs. That is to say, all the CORESETs configured by the network device can be divided into multiple groups. When the PDCCH corresponding to a certain group of CORESETs schedules a PDSCH, the default beam of the PDSCH adopts the TCI-state currently activated by the CORESET with the smallest or largest index in the CORESET group. The "specific index value" may be an index value related to the transmission site. Among them, the CORESETs corresponding to the same transmission site adopt the same index value, and the CORESETs corresponding to different transmission sites adopt different index values.

[0349] As an optional embodiment, each CORESET in the first CORESET group is associated with an index, the indexes of the CORESETs in the first CORESET group are the same, and the indexes of the CORESETs in the first CORESET group are different from the indexes of the CORESETs in other CORESET groups.

[0350] In the embodiments of the present application, the terminal device may determine the two TCI-states of the two PDSCHs respectively in the above manner, and then use the two TCI-states to receive and cache data. For example, determine the first TCI-state of the first PDSCH scheduled by the first PDCCH, and determine the second TCI-state of the second PDSCH scheduled by the second PDCCH. For each of the above TCI-states, a caching time interval may be determined, and the terminal device may use the TCI-state to receive and cache data within the caching time interval. The caching time interval refers to consecutive K symbols starting from the first symbol of the PDCCH corresponding to the TCI-state, or consecutive K symbols starting from the last symbol of the PDCCH corresponding to the TCI-state, or consecutive K symbols starting from the first symbol after the PDCCH corresponding to the TCI-state. Wherein, K is the number of symbols corresponding to a preset threshold. It should be understood that the above K may be a value specified by the protocol, or a value indicated by the network device to the terminal device, or a value reported by the terminal device to the network device. For example, K may be the value of the above preset threshold (TimeDurationForQCL).

[0351] How to cache data using the above two TCI-states depends on the capabilities of the terminal device and can be divided into the following two cases:

[0352] Case 1: The caching time intervals corresponding to the two TCI-states do not overlap, or the terminal device can receive using both of these two TCI-states simultaneously;

[0353] Case 2: The cached symbol ranges corresponding to the two TCI-states overlap, and the terminal device cannot receive using both of these two TCI-states simultaneously.

[0354] Regarding whether the terminal device can receive using multiple TCI-states, the terminal device may report it to the network device through the capability reporting procedure.

[0355] As an optional embodiment, the terminal device may report to the network device through the terminal capability reporting procedure whether it supports the above mechanism of transmitting PDSCH using the first TCI-state, that is, determining a default TCI-state for each CORESET group as the default TCI-state of the PDSCH scheduled by the PDCCH corresponding to the CORESET group. When the terminal device supports this mechanism, the first TCI-state (i.e., the above default TCI-state) in the embodiments of the present application is used to transmit PDSCH; otherwise, the method in the embodiments of the present application is not used.

[0356] Optionally, the terminal device may send terminal capability information to the network device, and the terminal capability information may indicate whether each CORESET group corresponds to a first TCI-state. That is, when the reception time interval between the DCI and its corresponding PDSCH is less than the preset threshold, one CORESET group corresponds to one TCI-state. When each CORESET group corresponds to a first TCI-state, and the reception time interval between the DCI and its corresponding PDSCH is less than the preset threshold, the network device may use the first TCI-state of the CORESET group corresponding to the DCI to send the PDSCH. Correspondingly, the terminal device may use the first TCI-state of the CORESET group corresponding to the DCI to receive the PDSCH.

[0357] Optionally, the terminal device may send terminal capability information to the network device, and the terminal capability information may indicate whether each packet index value corresponds to a first TCI state. That is, when the reception time interval between the DCI and its corresponding PDSCH is less than the preset threshold, one packet index value corresponds to one TCI-state. When each packet index value corresponds to a first TCI state, and the reception time interval between the DCI and its corresponding PDSCH is less than the preset threshold, the network device may use the first TCI-state corresponding to the packet index value of the CORESET corresponding to the DCI to send the PDSCH. Correspondingly, the terminal device may use the first TCI-state corresponding to the packet index value of the CORESET corresponding to the DCI to receive the PDSCH.

[0358] In the above case 1, the receiving the downlink signal by using N transmission configuration indication states TCI-state includes: receiving the downlink signal by using the first TCI-state in a first time interval, where the first time interval is a time interval composed of the first symbol or the last symbol of the first PDCCH, or the first symbol after the first PDCCH, and continuously K symbols. That is, the first time interval is the buffer time interval corresponding to the above first TCI-state.

[0359] Similarly, for the second PDCCH, the second TCI-state can be adopted to receive the downlink signal within the second time interval, which is a time interval composed of K consecutive symbols starting from the first symbol or the last symbol of the second PDCCH, or the first symbol after the first PDCCH. That is, the second time interval is the buffer time interval corresponding to the above second TCI-state. The determination method of the second TCI-state is the same as that of the first TCI-state described above, and will not be elaborated here.

[0360] Figure 8 Fig. shows a schematic diagram of using two TCI-states to buffer the downlink signal in an embodiment of the present application (corresponding to Case 1). In Figure 8 it, the time interval composed of K consecutive symbols starting from the first symbol after PDCCH 1 is the first time interval, and the terminal device can use TCI-state #1 to receive and buffer the downlink signal within this first time interval. The downlink signal may include PDSCH 1 scheduled by PDCCH 1; the time interval composed of K consecutive symbols starting from the first symbol after PDCCH 2 is the second time interval, and the terminal device can use TCI-state #2 to receive and buffer the downlink signal within this second time interval. The downlink signal may include PDSCH 2 scheduled by PDCCH 2.

[0361] In the above Case 2, the method of receiving the downlink signal by using N transmission configuration indication states (TCI-states) includes: using the first TCI-state to receive the downlink signal within the first time interval; using the second TCI-state among the N TCI-states to receive the downlink signal within the second time interval; wherein, the transmission time of the first PDCCH is before the transmission time of the second PDCCH, and the time interval composed of K consecutive symbols starting from the first moment overlaps with the time interval composed of K consecutive symbols starting from the second moment. The first time interval is the first half of the time interval composed of the first moment to the third moment, the second time interval is the second half of the time interval composed of the first moment to the third moment, the first moment is the first symbol or the last symbol of the first PDCCH, or the first symbol after the first PDCCH, the second moment is the first symbol or the last symbol of the second PDCCH, or the first symbol after the second PDCCH, and the third moment is the Kth symbol after the second moment.

[0362] Since the terminal device cannot receive using these two TCI-states simultaneously, the terminal device can receive signals in a time-division manner using the two TCI-states for buffering. In one possible implementation, the terminal device can divide all symbols corresponding to the union of the buffered symbol ranges of the first TCI-state and the second TCI-state into two halves (including the first half and the second half). The first half corresponds to the first TCI-state, and the second half corresponds to the second TCI-state. That is, the terminal device can receive and buffer the downlink signals on the symbols in the first half using the first TCI-state, and receive and buffer the signals on the symbols in the second half using the second TCI-state. If the total number of symbols is odd and cannot be evenly divided, optionally, the first half of the symbols can have one or more additional symbols. For example, the number of symbols in the first half can be determined by rounding up the total number of symbols divided by 2, and the remaining symbols are used as the second half of the symbols. Optionally, the first half of the symbols can have one or more fewer symbols. For example, the number of symbols in the first half can be determined by rounding down the total number of symbols divided by 2, and the remaining symbols are used as the second half of the symbols.

[0363] Figure 9 Another schematic diagram showing another way of buffering downlink signals using two TCI-states in an embodiment of the present application is shown (corresponding to case 2). In Figure 9 this case, after taking the union of the buffering time intervals of PDCCH 1 and PDCCH 2 and then dividing it into two equal halves, the first time interval is the first half. The terminal device can receive and buffer the downlink signals using TCI-state #1 within this first time interval, and the downlink signals may include PDSCH 1 scheduled by PDCCH 1; the second time interval is the second half. The terminal device can receive and buffer the downlink signals using TCI-state #2 within this second time interval, and the downlink signals may include PDSCH 2 scheduled by PDCCH 2.

[0364] In another possible implementation, the terminal device can evenly divide the overlapping part of the symbols. The first half of the symbols belongs to the previous buffered symbol range, and the second half of the symbols belongs to the subsequent buffered symbol range.

[0365] Optionally, if the time interval of a certain TCI-state determined by the above method spans multiple time slots, the symbols in the first time slot, the symbols in the last time slot, or the symbols in the time slot with the largest number of symbols can be used. The embodiments of the present application do not limit this. For example, the first time interval of the first TCI-state determined by the above method spans two time slots, occupying symbols {11, 12, 13, 0, 1, 2, 3, 4, 5, 6}, where {11, 12, 13} are the three symbols of the previous time slot, and {0, 1, 2, 3, 4, 5, 6} are the seven symbols of the subsequent time slot. When the terminal device uses the first TCI-state to buffer downlink data, if the terminal device uses the symbols in the first time slot, it can use the symbols {11, 12, 13}; if the terminal device uses the symbols in the last time slot, it can use the symbols {0, 1, 2, 3, 4, 5, 6}; if the terminal device uses the symbols in the time slot with the largest number of symbols, it can use the symbols {0, 1, 2, 3, 4, 5, 6}.

[0366] As an optional embodiment, the method further includes: if the time interval is greater than or equal to the preset threshold, it indicates that there is no PDSCH in the buffered downlink signal. The terminal device can discard the buffered downlink signal, determine a third TCI-state, and use the third TCI-state to receive the first PDSCH. Specifically, when the first PDCCH carries the information of the TCI-state, the third TCI-state is determined according to the first PDCCH. When the first PDCCH does not carry the information of the TCI-state, the third TCI-state can be a default TCI-state, or the terminal device determines the third TCI-state by other means. For example, the TCI-state corresponding to the first PDCCH is determined as the third TCI-state.

[0367] The following describes in two cases.

[0368] Case 1: The DCI type carried by the first PDCCH is DCI format 1_1, and the tci-PresentInDci parameter in the CORESET corresponding to the first PDCCH is configured as "enabled". At this time, the terminal device can use the TCI-state indicated in the DCI as the TCI-state of the first PDSCH.

[0369] Case 2: The DCI type carried by the first PDCCH is DCI format 1_0, or the parameter tci-PresentInDci is not configured in the CORESET corresponding to the first PDCCH. At this time, there is no TCI field in the DCI, and the information of the TCI-state cannot be indicated. The terminal device can use the TCI-state of this first PDCCH as the TCI-state of the first PDSCH.

[0370] After determining the two TCI-states for transmitting the two PDSCHs through the above method, the terminal device can receive the two PDSCHs according to these two TCI-states respectively. Specifically, the terminal device can determine the information of the transmission beam according to the reference signals included in these two TCI-states, so as to determine the corresponding reception beam, and use the reception beam to receive the two PDSCHs transmitted on these two transmission beams.

[0371] In the data transmission method of the embodiment of the present application, the terminal device can determine the TCI-state adopted by the network device for data transmission through various methods, so that the terminal device determines the reception beam according to the TCI-state and receives the data sent by the network device, thereby improving the data transmission efficiency.

[0372] Figure 10 FIG. shows a schematic diagram of another data transmission scenario of the embodiment of the present application. This data transmission scenario is based on a multi-TRP transmission scenario. The network device repeatedly sends the same PDSCH to the terminal device through multiple TRPs at different times, that is, the PDSCHs sent by each TRP are the same PDSCH. This transmission method can improve the reliability of data transmission. Each TRP uses one TCI-state to send the PDSCH, so the terminal device can determine multiple TCI-states to correctly receive the PDSCH. The above network device sends the PDCCH to the terminal device, which can be sent by a single TRP (using a single TCI-state) or by multiple TRPs (using multiple TCI-states). The embodiment of the present application does not limit this. For ease of description, Figure 10Two TRPs are shown (i.e., the terminal device can determine two TCI-states). Specifically, TRP 1 sends a PDCCH to the terminal device for scheduling the PDSCH of TRP 1 and the PDSCH of TRP 2. TRP 1 uses TCI-state#1 to send the PDSCH to the terminal device in the first time period (Time#1), and TRP 2 uses TCI-state#2 to send the PDSCH to the terminal device in the second time period (Time#2). The first time period and the second time period are different. In this way, the terminal device determines TCI-state#1 and TCI-state#2 to correctly receive the PDSCH 1 transmitted twice.

[0373] Figure 10 The scenario shown is similar to Figure 3 but the difference is that Figure 3 in the scenario of Figure 10 the time period of the PDSCH sent by each TRP is not limited, while

[0374] For Figure 10 the data transmission method in the shown scenario, the following steps can be included:

[0375] Step 1: The network device sends a PDCCH to the terminal device, and the PDCCH carries a DCI. All TCI-states corresponding to the PDSCH transmitted multiple times are carried in the DCI. Alternatively, the network device can also send multiple PDCCHs to the terminal device, and the same DCI is carried in all of the multiple PDCCHs. All TCI-states corresponding to the PDSCH transmitted multiple times are carried in the DCI. Correspondingly, the terminal device receives and processes the PDCCH.

[0376] Step 2: Caching of data. In order for the terminal device to avoid missing the PDSCH with a scheduling time interval less than the preset threshold, the terminal device receives the signal using the default TCI-state and caches it until the reception and processing of the PDCCH are completed. Since the network device sends the PDSCH using multiple TCI-states, multiple default TCI-states can be determined. That is, when the time interval between the PDCCH and the PDSCH it schedules is less than the preset threshold, the terminal device can determine multiple TCI-states. The specific determination method is the same as the above method 400 and will not be elaborated here.

[0377] It should be noted that since there are multiple PDSCHs (even multiple PDCCHs) in the embodiments of the present application, the time interval in the condition "when the time interval between the PDCCH and the PDSCH it schedules is less than the preset threshold" can be expressed in any of the following ways:

[0378] (1) The time interval between the PDCCH and the first PDSCH;

[0379] (2) The time offset between the first symbol or the last symbol of the PDCCH, or the first symbol after the PDCCH, and the first symbol of the first PDSCH;

[0380] (3) The time interval between the PDCCH and the last PDSCH;

[0381] (4) The time offset between the first symbol or the last symbol of the PDCCH, or the first symbol after the PDCCH, and the first symbol of the last PDSCH.

[0382] It should be understood that the above-mentioned first PDSCH refers to the first PDSCH transmitted in time, and the above-mentioned last PDSCH refers to the last PDSCH transmitted in time.

[0383] In addition, if there are multiple PDCCHs, the PDCCH in the above description can specifically refer to any one of the multiple PDCCHs, for example, the first PDCCH or the last PDCCH. Similarly, the first PDSCH refers to the first PDSCH transmitted in time, and the last PDSCH refers to the last PDSCH transmitted in time.

[0384] Step 3: Reception and processing of data. After the terminal device completes the reception and processing of the PDCCH, it can determine the information of the PDSCH, such as the scheduling time interval, the time-frequency resources for transmission, the TCI-state, etc. If it is found according to the scheduling information in the PDCCH that the scheduling time interval of the scheduled PDSCH is less than the preset threshold, the terminal device can obtain the PDSCH from the downlink signal cached in the previous step according to the information of the time-frequency resources of the PDSCH carried in the PDCCH. If the scheduling time interval of the PDSCH scheduled by the PDCCH is not less than the preset threshold, it means that there is no PDSCH in the cached downlink signal. Therefore, the terminal device can discard the cached signal and determine the two TCI-states of the PDSCH according to the PDCCH to receive the PDSCH.

[0385] The following is described in two cases.

[0386] Scenario 1: The DCI type carried by the PDCCH is DCI format 1_1, and the tci-PresentInDci parameter in the CORESET corresponding to the PDCCH is configured as "enabled". At this time, the terminal device can use the two TCI-states indicated in the DCI as the two TCI-states of the PDSCH.

[0387] In the embodiments of this application, in addition to determining the above two TCI-states, the terminal device can also determine the repetition transmission times M of the PDSCH. In a possible implementation manner, the network device can restrict the transmissions of each PDSCH to be in the same time slot, then the repetition transmission times M of the PDSCH can be determined according to the number of downlink symbols available for PDSCH transmission in this time slot. For example, in this time slot, there are X downlink symbols available for PDSCH transmission. Each PDSCH transmission uses Y downlink symbols, and the repetition transmission times of the PDSCH are That is, X divided by Y and rounded down. The downlink symbols available for PDSCH transmission in this time slot specifically refer to all downlink symbols corresponding to the first symbol of the first PDSCH to the last symbol of this time slot. It should be understood that if there is a certain symbol interval required between each PDSCH, the number of symbols corresponding to these interval symbols can also be excluded.

[0388] Further, the network device can limit the repetition transmission of the PDSCH to be an integer multiple of 2. Exemplarily, assume is the number of PDSCH transmission times supported by the terminal device, calculate That is, calculate that the number of PDSCH transmission times supported is 2 to the power of P, and then take M = 2 × P. For example, S = 7, then P = 3 can be obtained. Therefore, M = 6.

[0389] Optionally, a threshold value can be used to limit the quantity of M. When the calculated value of M is greater than this threshold value, the limited value is also adopted; and when the calculated value of M is less than this limited value, the calculated value can be adopted.

[0390] Optionally, a threshold value can also be used to limit the quantity of P. When the calculated value of P is greater than this limited value, the limited value is also adopted; and when the calculated value of P is less than this limited value, the calculated value can be adopted.

[0391] It should be understood that the above rounding-down operation can also be replaced by rounding-up or rounding to the nearest integer. The embodiments of this application do not make any limitations on this.

[0392] Case 2: The DCI type carried by the PDCCH is DCI format 1_0, or the parameter tci-PresentInDci is not configured in the CORESET corresponding to the first PDCCH. At this time, there is no TCI field in the DCI, and the information of the TCI-state cannot be indicated. The terminal device can determine two TCI-states. The specific determination method is the same as the above method 400 and will not be elaborated here.

[0393] After determining the two TCI-states for PDSCH transmission, the terminal device receives the PDSCH according to these two TCI-states. Specifically, the terminal device determines the information of the transmission beam according to the reference signals included in these two TCI-states, so as to determine the corresponding reception beam to receive the PDSCH transmitted on these two transmission beams.

[0394] In the data transmission method of the embodiments of the present application, the network device sends the same PDSCH to the terminal device in different time periods. The terminal device can determine multiple TCI-states used by the network device for data transmission in various ways, so that the terminal device determines the reception beam according to the multiple TCI-states and receives the data sent by the network device, which not only improves the data transmission efficiency but also improves the data transmission reliability.

[0395] The embodiments of the present application also provide a data transmission method 500, which includes the following three steps:

[0396] Step 1: The network device sends downlink control information DCI, which is used to schedule the PDSCH. Correspondingly, the terminal device receives the DCI.

[0397] Step 2: The network device sends the PDSCH in the first cell using the first TCI-state; correspondingly, the terminal device receives the PDSCH based on the above first TCI-state.

[0398] Optionally, the above first TCI-state can also be expressed as a first QCL hypothesis, which is used to represent relevant parameters for PDSCH transmission, such as time-frequency offset information, receiving beam information, etc. For example, the first TCI-state may include a QCL-info of type typeA / typeB / typeC, which is used to represent the time-frequency offset information for PDSCH transmission. Specifically, this QCL-info includes a reference signal resource, indicating that the time-frequency offset of the PDSCH transmission is the same as that of this reference signal resource. Also for example, the first TCI-state may include a QCL-info of type typeD (it can also be said that this first TCI-state contains quasi-co-located QCL-TypeD information), which is used to represent the receiving beam information for PDSCH transmission. Specifically, this QCL-info includes a reference signal resource, indicating that the receiving beam of the PDSCH transmission is the same as that of this reference signal resource.

[0399] It should be understood that the above first cell can be a primary cell (Pcell), the primary cell in a secondary cell group (primary secondary cell, Pscell), a secondary cell (Scell), a PUCCH-Scell (a secondary cell configured with PUCCH) in a master cell group (MCG), a PUCCH-Scell in a secondary cell group (SCG), or other Scells in the SCG except for the PUCCH-Scell. The embodiments of the present application do not limit this.

[0400] In the above step one, the terminal device can determine the first TCI-state by using a variety of different methods. First, the methods that the terminal device can adopt will be introduced below.

[0401] Method 1: The terminal device can determine the above first TCI-state according to the DCI that schedules the PDSCH. That is, the DCI that schedules the PDSCH includes a TCI field, and the terminal device can determine the first TCI-state according to the TCI field in this DCI.

[0402] As an optional embodiment, the TCI-state indicated by the DCI is activated by signaling (such as MAC CE). Exemplarily, the MAC CE can activate multiple groups of TCI-state (also referred to as multiple TCI-state groups), and each TCI-state group can include one or two TCI-states. Each TCI-state group is associated with a TCI field value of the TCI field in the DCI. For example, the TCI field values 0 to 7 are respectively associated with a TCI-state group: {1, 2}, {3, 4}, {5, 6}, {7, 8}, {1}, {2}, {3}, {4}.

[0403] Method 2: The terminal device can use the TCI-state of the DCI that schedules the PDSCH as the first TCI-state.

[0404] That is, whatever TCI-state the DCI that schedules the PDSCH uses, the PDSCH transmission uses the same TCI-state. In other words, the PDSCH and its corresponding PDCCH satisfy the QCL relationship, which can specifically be a QCL relationship of type A / type B / type C / type D.

[0405] Method 3: The terminal device can use the TCI-state of a CORESET in the CORESET group of the DCI that schedules the PDSCH as the first TCI-state, such as the currently activated TCI-state of the COREEST.

[0406] Specifically, which CORESET to use can be the CORESET with the smallest or largest index in the CORESET group, or it can be the CORESET with the smallest or largest index among one or more CORESETs that the terminal device last heard (such as in the most recent time slot). The one or more CORESETs refer to the CORESETs in the above-mentioned CORESET group. The CORESET group corresponding to the DCI refers to the CORESET group composed of CORESETs that have the same first index (such as CORESETPoolIndex) value as the CORESET corresponding to the DCI. The first index is used to group the configured CORESETs, and the value can be 0 or 1. The configured CORESETs can be divided into two groups, and the CORESETs with the same first index value are in one group. It should be understood that if the first index values of all CORESETs are the same (for example, all are configured as 0 or all are configured as 1), or if none are configured, there is only one CORESET group in total.

[0407] Method 4: The terminal device may use the first resource of the second cell to determine the first TCI-state, that is, use this first resource as the QCL resource in the first TCI-state.

[0408] The QCL resource is the reference resource for QCL indication. The QCL resource may specifically refer to QCL resources of type A / type B / type C / type D, that is, the reference signal resources included in the QCL-info of type A / type B / type C / type D.

[0409] Optionally, when using the first resource to determine the QCL resource in the first TCI-state, it can be limited to only use resources of the same QCL type. For example, if the first resource is a type A QCL resource of a certain TCI-state, then the first resource can only be used as a type A resource in the first TCI-state. Similarly, if the first resource is a type B / type C / type D QCL resource of a certain TCI-state, then the first resource can only be used as a type B / type C / type D resource in the first TCI-state.

[0410] Optionally, when using the first resource to determine the QCL resource in the first TCI-state, it is not necessary to limit to only use resources of the same QCL type. For example, if the first resource is a type A QCL resource of a certain TCI-state, this first resource can not only be used as a type A resource in the first TCI-state, but also as a type D resource in the first TCI-state. Another example, when using the QCL resource in another TCI-state as the first resource to determine the QCL resource in the first TCI-state, if there is no type D QCL resource in this TCI-state, the type A QCL resource can be used as the type D QCL resource in the first TCI-state. It should be understood that in the above examples, although only type A and type D are described, the above method is also applicable to other types. That is to say, type A in the above examples can also be replaced by type B or type C or type D, and type D in the above examples can also be replaced by type A or type B or type C. The embodiments of the present application do not make limitations in this regard.

[0411] In this method, the second cell may be the first cell, or the scheduling cell of the first cell, or the Pcell or Pscell corresponding to the first cell, or the primary cell Pcell of the MCG corresponding to the first cell, or the primary cell PScell of the SCG corresponding to the first cell, or the PUCCH-scell of the MCG corresponding to the first cell, or the PUCCH-scell of the SCG corresponding to the first cell. It should be understood that the network device may configure a cell group for the terminal device, and each cell group includes a Pcell (or Pscell) and multiple Scells. For an Scell, the corresponding Pcell refers to the Pcell that belongs to the same cell group as this Scell.

[0412] Optionally, the terminal device may also determine which of the above cells the second cell is according to conditions. For example, if the first cell is configured with a CORESET, and / or the TCI-state of the PDSCH is activated in the first cell, the terminal device may determine the first cell as the second cell; if the first cell is not configured with a CORESET (for example, the currently activated BWP of the first cell is not configured with a CORESET), and / or the TCI-state of the PDSCH is not activated in the first cell (for example, the currently activated BWP of the first cell does not activate the TCI-state of the PDSCH), then the terminal device may determine one of the other cells except the first cell as the second cell.

[0413] For ease of understanding, the first resource will be explained below. The above-mentioned first resource may be an SSB, such as the SSB used during initial access. Alternatively, the first resource may be the QCL resource of the CORESET with the smallest or largest index among at least one CORESET configured by the second cell / listened to in the most recent time slot, or the QCL resource of the CORESET with the smallest or largest index among at least one CORESET configured by the active BWP of the second cell / listened to in the most recent time slot. Among them, the QCL resource of the CORESET refers to the QCL resource within the currently active TCI-state of the CORESET. Alternatively, the first resource may be the QCL resource of the CORESET with the smallest or largest index among the CORESET groups corresponding to the PDSCH configured by the second cell / listened to in the most recent time slot, or the QCL resource of the CORESET with the smallest or largest index among the CORESET groups corresponding to the PDSCH configured by the active BWP of the second cell / listened to in the most recent time slot. Alternatively, the first resource may also be the QCL resource of one or more (such as two) TCI-states with the smallest / largest index in the currently active PDSCH TCI-state configured by the active BWP of the second cell, or the QCL resource of one or more (such as two) TCI-states corresponding to the smallest / largest TCI field value in the currently active PDSCH TCI-state configured by the active BWP of the second cell. Alternatively, the first resource may also be the QCL resource of the TCI-state corresponding to the smallest / largest one or more (such as two) TCI field values in the TCI field value corresponding to a single TCI-state in the active BWP of the second cell. Alternatively, the first resource may also be the QCL resource of multiple (such as two) TCI-states corresponding to the smallest / largest TCI field value among the TCI field values corresponding to multiple (such as two) TCI-states. If each TCI field value corresponds to a single TCI-state, only the QCL resource of a single TCI-state is used, for example, the QCL resource determined by any one of the previous methods.

[0414] Optionally, under certain conditions, the terminal device may use the above method to determine the first TCI-state. Below, the satisfied conditions will be described in detail.

[0415] Condition 1: The PDSCH transmission of the first cell is scheduled by the second cell (which can also be replaced by the first cell being a Scell), and there is no active TCI-state for PDSCH transmission in the first cell.

[0416] Optionally, Condition 1 can also be a further combination of the above conditions and one or more of the following conditions. The combination can be a union of conditions, such as Condition a AND Condition b, or an intersection of conditions, such as Condition a OR Condition b.

[0417] 1. The subcarrier spacing used by the first cell is the same as the subcarrier spacing used by the second cell;

[0418] 2. The subcarrier spacing used by the first cell is different from the subcarrier spacing used by the second cell;

[0419] 3. The network device does not configure a CORESET group for the terminal device in the second cell;

[0420] 4. The network device configures a CORESET group for the terminal device in the second cell;

[0421] 5. The second cell uses FR2 frequency for transmission (which can also be replaced by configuring a TCI-state including QCL-info of type D in the second cell);

[0422] 6. The second cell uses FR1 frequency for transmission (which can also be replaced by not configuring a TCI-state including QCL-info of type D in the second cell).

[0423] When Condition 1 is satisfied (for example, the PDSCH transmission of the first cell is scheduled by the second cell (which can also be replaced by the first cell being a Scell), and there is no activated TCI-state for PDSCH transmission in the first cell, and the subcarrier spacing used by the first cell is different from the subcarrier spacing used by the second cell), the PDSCH transmission satisfies one or more of the following constraints:

[0424] 1. The time interval between the PDSCH and its corresponding PDCCH (for example, the time interval between the last symbol of the PDCCH and the first symbol of the PDSCH) is greater than or equal to a preset threshold timeDurationForQCL. The preset threshold timeDurationForQCL represents the time required for the terminal device to receive and process the PDCCH and prepare the receive beam for the PDSCH (that is, it may take a certain amount of time to switch to the receive beam of the PDSCH). It should be understood that the name of this preset threshold is not limited to timeDurationForQCL in the embodiments of this application.

[0425] 2. The PDCCH contains a TCI field (for example, the DCI type carried by the PDCCH is DCI format 1-1 and the RRC parameter tci-PresentInDCI is configured to be enabled), or the PDCCH indicates the QCL information of the PDSCH (such as the QCL information of type D).

[0426] When the above Condition 1 is satisfied, the terminal device uses one of the above Methods 1 to 4 to determine the first TCI-state.

[0427] In another implementation, when the above Condition 1 is satisfied, data transmission is restricted. That is to say, the protocol can stipulate that in the case corresponding to Condition 1, the network device cannot send data to the terminal device, and the terminal device will not receive data from the network device either. For example, the protocol stipulates that when the PDSCH transmission of the first cell or the first cell is scheduled by the second cell, and there is no activated TCI-state for PDSCH transmission in the first cell, and the subcarrier spacing used by the first cell is different from the subcarrier spacing used by the second cell, the network device does not perform data transmission to the terminal device. That is to say, for a Scell or a cell scheduled by another cell, if the subcarrier spacing it uses is different from the subcarrier spacing of its scheduling cell, then before the TCI-state of its PDSCH is activated, the terminal device will not receive data from this cell, and will only receive data from this cell until the TCI-state of the PDSCH of this cell is activated.

[0428] Condition 2: The PDSCH transmission of the first cell is scheduled by the second cell (which can also be replaced by the first cell being a Scell), and the second cell uses FR2 frequency for transmission (which can also be replaced by the second cell is configured with a TCI-state including QCL-info of type D).

[0429] Optionally, Condition 2 can also be a further combination of the above conditions and one or more of the following conditions. The combination can be a union of conditions, such as Condition a and Condition b, or an intersection of conditions, such as Condition a or Condition b.

[0430] 1. The subcarrier spacing used by the first cell is the same as the subcarrier spacing used by the second cell;

[0431] 2. The subcarrier spacing used by the first cell is different from the subcarrier spacing used by the second cell;

[0432] 3. The time interval between the DCI scheduling the PDSCH and the PDSCH is less than a preset threshold timeDurationForQCL. The preset threshold timeDurationForQCL represents the time required for the terminal device to receive and process the PDCCH and prepare the receiving beam for the PDSCH (i.e., it may take a certain amount of time to switch to the receiving beam of the PDSCH). It should be understood that the name of this preset threshold is not limited to timeDurationForQCL in the embodiments of the present application.

[0433] 4. The time interval between the DCI scheduling the PDSCH and the PDSCH is greater than or equal to the preset threshold timeDurationForQCL;

[0434] 5. The DCI scheduling the PDSCH includes a TCI field (for example, the type of the DCI is DCI format 1-1 and the RRC parameter tci-PresentInDCI is configured to be enabled);

[0435] 6. The DCI scheduling the PDSCH does not include a TCI field (for example, the type of the DCI is DCI format 1-0 or the RRC parameter tci-PresentInDCI is not configured);

[0436] 7. The network device does not configure a CORESET for the terminal device in the second cell;

[0437] 8. The network device configures a CORESET for the terminal device in the second cell;

[0438] 9. The TCI-state for PDSCH transmission is not activated in the second cell;

[0439] 10. The TCI-state for PDSCH transmission is activated in the second cell;

[0440] When the above Condition 2 is satisfied, the terminal device can determine the first TCI-state by using one of the above Method 1 to Method 4 according to the situation.

[0441] For example, when condition two (the PDSCH transmission of the first cell is scheduled by the second cell (which can also be replaced by the first cell being a Scell), and the second cell uses FR2 frequency transmission (which can also be replaced by the second cell being configured with a TCI-state including QCL-info of type D), and the time interval between the DCI scheduling the PDSCH and the PDSCH is less than the preset threshold timeDurationForQCL, and the network device does not configure a CORESET for the terminal device in the second cell and / or there is no active TCI-state for PDSCH transmission in the second cell) is satisfied, the above method four is adopted (for example, using the TCI-state of the CORESET with the smallest index among one or more CORESETs configured / listened to most recently in the BWP activated by the terminal device in the second cell as the first TCI-state).

[0442] For another example, when condition two (the PDSCH transmission of the first cell is scheduled by the second cell (which can also be replaced by the first cell being a Scell), and the second cell uses FR2 frequency transmission (which can also be replaced by the second cell being configured with a TCI-state including QCL-info of type D), and the DCI scheduling the PDSCH does not include a TCI field, and the time interval between the DCI scheduling the PDSCH and the PDSCH is greater than or equal to the preset threshold timeDurationForQCL) is satisfied, the above method two is adopted (for example, using the TCI-state of the PDCCH scheduling the PDSCH as the first TCI-state).

[0443] Condition three: The PDSCH transmission of the first cell is scheduled by the second cell (which can also be replaced by the first cell being a Scell), and the second cell uses FR1 frequency transmission (which can also be replaced by the second cell not being configured with a TCI-state including QCL-info of type D).

[0444] Optionally, condition three can also be a further combination of the above conditions and one or more of the following conditions. The combination can be a union of conditions, such as condition a AND condition b, or an intersection of conditions, such as condition a OR condition b.

[0445] 1. The subcarrier spacing used by the first cell is the same as that used by the second cell;

[0446] 2. The subcarrier spacing used by the first cell is different from that used by the second cell;

[0447] 3. The network device does not configure a CORESET for the terminal device in the second cell;

[0448] 4. The network device configures a CORESET for the terminal device in the second cell;

[0449] 5. There is no activated TCI-state for PDSCH transmission in the second cell;

[0450] 6. There is an activated TCI-state for PDSCH transmission in the second cell;

[0451] When the above condition three is satisfied (for example, the PDSCH transmission of the first cell is scheduled by the second cell (which can also be replaced by the first cell being a Scell), and the second cell uses FR1 frequency for transmission (which can also be replaced by there is no configured TCI-state including typeD QCL-info in the second cell), and the network device does not configure a CORESET for the terminal device in the second cell and / or there is no activated TCI-state for PDSCH transmission in the second cell), the PDSCH transmission satisfies one or more of the following constraints:

[0452] 1. The time interval between the PDSCH and its corresponding PDCCH (for example, the time interval between the last symbol of the PDCCH and the first symbol of the PDSCH) is greater than or equal to a preset threshold timeDurationForQCL. The preset threshold timeDurationForQCL represents the time required for the terminal device to receive and process the PDCCH and prepare the receiving beam for the PDSCH (that is, it may take a certain amount of time to switch to the receiving beam of the PDSCH). It should be understood that the name of this preset threshold is not limited to timeDurationForQCL in the embodiments of this application.

[0453] 2. The PDCCH contains a TCI field (for example, the DCI type carried by the PDCCH is DCI format1-1 and the RRC parameter tci-PresentInDCI is configured to be enabled), or the PDCCH indicates the QCL information of the PDSCH (such as typeD QCL information).

[0454] When the above condition three is satisfied, the terminal device uses one of the methods one to four above to determine the first TCI-state.

[0455] In another implementation, when the above condition three is satisfied, it is specified that data transmission cannot be performed. That is to say, the protocol can stipulate that in the case corresponding to condition three, the network device cannot send data to the terminal device, and the terminal device will not receive data from the network device either. For example, the protocol stipulates that when the first cell or the PDSCH transmission of the first cell is scheduled by the second cell, and the second cell uses FR1 frequency transmission (which can also be replaced by the TCI-state in the second cell not configured with QCL-info including type D), and there is no activated TCI-state for PDSCH transmission in the second cell, the network device does not perform data transmission to the terminal device. That is to say, for a Scell or a cell scheduled by another cell, if its scheduling cell uses FR1 frequency transmission (which can also be replaced by the TCI-state in its scheduling cell not configured with QCL-info including type D), then before the TCI-state of its PDSCH is activated, the terminal device will not receive data from this cell, and will only receive data from this cell until the TCI-state of its PDSCH is activated.

[0456] Optionally, the above method can also be extended to the determination of the TCI-state of PDCCH. That is, the PDSCH in the above method can be replaced by PDCCH to determine the TCI-state of PDCCH transmission. For example, if the first cell is a Scell and its PDCCH TCI-state has not been activated, at this time, the terminal device can use various methods corresponding to the above method one to method three to determine the first TCI-state.

[0457] It should be understood that PDCCH may not be transmitted in the above situation either. For example, the protocol stipulates that when the first cell is a Scell and there is no activated TCI-state for PDCCH transmission in the first cell, the network device does not perform PDCCH transmission. That is to say, for a Scell, before the TCI-state of its PDCCH is activated, the terminal device will not receive PDCCH from this cell, and will only receive data from this cell until the TCI-state of its PDCCH is activated.

[0458] Through the method of the embodiments of the present application, the terminal device can determine the TCI-state used by the network device for data transmission in various ways, so as to receive the PDSCH, which not only improves the efficiency of data transmission, but also improves the reliability of data transmission.

[0459] The embodiments of the present application also provide a data transmission method 600, and at the same time propose a MAC CE format for activating multiple TCI-states. The method includes the following steps:

[0460] Step 1: The network device determines and sends a first signaling. Correspondingly, the terminal device receives the first signaling, which is used to activate multiple Transmission Configuration Indicator (TCI)-state groups. Each TCI-state group in the multiple TCI-state groups includes one or two TCI-states.

[0461] Step 2: The terminal device determines the mapping method of each TCI-state to the TCI field value according to the configuration information of the Control Resource Set (CORESET) or the indication information in the first signaling. Each TCI-state here refers to the TCI-state included in the TCI-state group indicated by the first signaling above.

[0462] In the embodiment of the present application, the network device can activate the TCI-states for two Transmit and Receive Points (TRP) transmissions simultaneously through the first signaling above to enable multi-TRP transmission. In a possible implementation manner, the first signaling may be a Medium Access Control (MAC) Control Element (CE) signaling.

[0463] As an optional embodiment, the above mapping method includes a first mapping method. Under the first mapping method, in the multiple TCI-state groups, the j-th TCI-state in the i-th TCI-state group represents the j-th TCI-state corresponding to the TCI field value i, where i is an integer greater than or equal to 0, and j is a positive integer. Therefore, under the first mapping method, one TCI field value corresponds to one or two TCI-states.

[0464] As an optional embodiment, the above mapping method includes a second mapping method. Under the second mapping method, in the multiple TCI-state groups, the j-th TCI-state in the i-th TCI-state group represents the TCI-state corresponding to the TCI field value i in the Physical Downlink Control Channel (PDCCH) corresponding to the CORESET with the packet index value of j - 1, where i is an integer greater than or equal to 0, and j is a positive integer. Therefore, under the second mapping method, one TCI field value corresponds to one TCI-state.

[0465] It should be understood that the first signaling indicates multiple TCI-state groups. i represents the index of the multiple TCI-state groups, starting from 0, and the maximum value is the number of the multiple TCI-state groups; j represents the index of the TCI-states in each TCI-state group, starting from 1, and j = 1 or 2. Exemplarily, in the first signaling, the TCI-state j of the TCI-state group i can be specifically indicated by the TCI-state ID i,j For example, the TCI-state ID 0,1Used to indicate the first TCI-state in TCI-state group 0, TCI-state ID 0,2 Used to indicate the second TCI-state in TCI-state group 0. In this application, TCI-state group i can also be referred to as the (i + 1)-th TCI-state group.

[0466] As an optional embodiment, the method further includes: the terminal device sends terminal capability parameters, and correspondingly, the network device receives the terminal capability parameters, where the terminal capability parameters include one or more of the following:

[0467] The first capability parameter is used to indicate the upper limit of the number of different TCI states corresponding to the CORESET associated with one packet index value when the configured CORESET is associated with two different packet index values;

[0468] The second capability parameter is used to indicate the upper limit of the number of different TCI states corresponding to the configured CORESET when the configured CORESET is associated with two different packet index values;

[0469] The third capability parameter is used to indicate the upper limit of the number of different TCI states corresponding to the configured CORESET when the configured CORESET is associated with the same packet index value;

[0470] The fourth capability parameter is used to indicate the upper limit of the number of different TCI states in the TCI states indicated by the first signaling;

[0471] The fifth capability parameter is used to indicate the upper limit of the number of different TCI states in the TCI states indicated by the first signaling when the configured CORESET is associated with two different packet index values;

[0472] The sixth capability parameter is used to indicate the upper limit of the number of different TCI states in the TCI states indicated by the first signaling when the configured CORESET is associated with the same packet index value;

[0473] The seventh capability parameter is used to indicate the upper limit of the number of different TCI states in the TCI states indicated by the first signaling when the first mapping method is adopted; or,

[0474] The eighth capability parameter is used to indicate the upper limit of the number of different TCI states in the TCI states indicated by the first signaling when the second mapping method is adopted.

[0475] In the embodiments of the present application, the above different capability parameters reflect the terminal capabilities at different granularities. The terminal device can flexibly report all or part of the capability parameters according to the actual situation, so that the TCI state activated by the network device for the terminal device through the first signaling meets the capabilities of the terminal device, thereby improving the subsequent data transmission efficiency.

[0476] Exemplarily, assume that 5 CORESETs are configured (with indexes 0 to 4 respectively). Among them, the packet index values associated with CORESTE 0, CORESTE1, and CORESET 3 are 1. Then, CORESTE 0, CORESTE 1, and CORESET 3 form CORESET group 1. The packet index values associated with CORESTE 2 and CORESET 4 are 2. Then, CORESTE 2 and CORESET 4 form CORESET group 2. Therefore, the above first capability parameter can be the upper limit value of the number of different TCI states corresponding to the CORESETs in CORESET group 1, or the upper limit value of the number of different TCI states corresponding to the CORESETs in CORESET group 2. The above second capability parameter can be the upper limit value of the number of different TCI states corresponding to the above 5 CORESETs (CORESET group 1 and CORESET group 2). Exemplarily, assume that 5 CORESETs are configured (with indexes 0 to 4 respectively), and these 5 CORESETs are associated with the same packet index value. The third capability parameter can be the upper limit value of the number of different TCI states corresponding to the above 5 CORESETs. The subsequent parameters are similar and will not be listed one by one. It should be understood that the fifth capability parameter is the same as the eighth capability parameter, and the sixth capability parameter is the same as the seventh capability parameter.

[0477] In the embodiments of the present application, it is only illustrated by taking an example that one or two TCI-states can be included in one TCI-state group. However, it should be understood that multiple TCI-states can also be included in one TCI-state group, and the embodiments of the present application do not limit this. The following combines Figure 13 to describe the embodiments of the present application in detail.

[0478] Figure 13 A format schematic diagram of a MAC CE signaling for activating a TCI-state is shown. This MAC CE signaling can be used for TCI-state activation in the following two cases.

[0479] Scenario 1: The data sent by two TRPs is scheduled by one DCI, and this DCI can be sent by one of the TRPs. For example, the data sent by TRP 1 and TRP 2 is scheduled by one DCI, and this DCI can be sent by TRP 1 or TRP 2. The TCI-state field in this DCI indicates two TCI-states. Each field value of the TCI field in the DCI can be associated with one or two TCI-states. When the field value of the TCI field is associated with two TCI-states, this field value can indicate the two TCI-states.

[0480] Scenario 2: The data sent by two TRPs is scheduled by their respective DCIs. For example, TRP 1 and TRP 2 each send a DCI to schedule the data sent on TRP 1 and TRP 2 respectively. Each field value of the TCI field in these two DCIs is associated with one TCI-state, which is used to indicate one TCI-state respectively.

[0481] In Scenario 1 above, the above MAC CE signaling can be used to activate multiple TCI-state groups. Each TCI-state group includes one or two TCI-states, and each TCI-state group can correspond to one TCI field value.

[0482] Among them, the R field is a reserved field and has no use for the time being. The serving cell ID occupies 5 bits and is used to indicate the ID of the cell, that is, which cell's TCI-state is activated by this MAC CE; the BWP ID occupies 2 bits and is used to indicate the ID of the BWP, that is, which BWP's TCI-state is activated by this MAC CE; the TCI-state ID i,1 represents the first TCI-state in the (i + 1)-th TCI-state group (i.e., TCI-state group i), and the TCI-state ID i,2 represents the second TCI-state in the (i + 1)-th TCI-state group. These two TCI-states are grouped together and associated with the TCI field value i. The above i ∈ {0, 1,..., N}. In other words, the TCI-state ID i,j represents the j-th TCI-state corresponding to the TCI field value i. For example, the TCI-state ID i,1 represents the first TCI-state corresponding to the TCI field value i, and the TCI-state ID i,2Indicates the second TCI-state corresponding to the TCI field value i. Here, j ∈ {1, 2}. It should be understood that if a TCI-state group includes a greater number of TCI-states, then a TCI field value can correspond to a greater number of TCI-states, and the value of j can also be other numerical values.

[0483] C i Used to indicate whether there is a second TCI-state (i.e., TCI-state ID i,2 ) in the (i + 1)-th TCI-state group. If there is a second TCI-state, then this TCI-state group contains two TCI-states; if there is no second TCI-state, then this TCI-state group only includes a single TCI-state. Specifically, from the perspective of parsing the MAC CE format, the terminal device can determine whether there is an octet corresponding to the TCI-state ID i according to the value of C. i,2 Exemplarily, if C i = 1, the terminal device can determine that there is an octet corresponding to the TCI-state ID i,2 in the MAC CE, that is, determine that the eight bits following the TCI-state ID i,1 carry an S i field and a TCI-state ID i,2 field. If C i = 0, the terminal device can determine that there is no octet corresponding to the TCI-state ID i,2 in the MAC CE, that is, determine that the eight bits following the TCI-state ID i,1 carry a C i+1 field and a TCI-state ID i+1,1 field.

[0484] S i Used to indicate whether there is an (i + 2)-th TCI-state group in multiple TCI-state groups, or used to indicate whether there is a TCI-state ID i+1,1 in the MAC CE signaling, or used to indicate whether there is an octet corresponding to the TCI-state ID i+1,1 in the MAC CE signaling. Exemplarily, if S i = 1, the terminal device can determine that there is an octet corresponding to the TCI-state ID i+1,1 in the MAC CE, that is, determine that the eight bits following the TCI-state ID i,2The following eight bits carry a C i+1 field and a TCI-state ID i+1,1 field. If S i = 0, the terminal device can determine that there is no TCI-state ID i+1,1 corresponding octet in the MAC CE, that is, it is determined that there are no other bits after the TCI-state ID i,2 . In other words, the end position of the MAC CE is determined by S i . If S i = 0, it means that the octet corresponding to the TCI-state ID i,2 is the last octet and there are no other octets after it. Optionally, S i can also be used as a reserved field.

[0485] The terminal device can determine the number N + 1 of TCI-state groups activated by the MAC CE signaling through the above method. Optionally, when the number of TCI-state groups activated by the MAC CE is less than the number of TCI field values, each activated TCI-state group can be mapped in sequence to the first few smallest TCI field values.

[0486] It should be understood that the number N + 1 of TCI-state groups activated by the MAC CE can also be configured through RRC parameters (such as tci-PresentInDCI, tci-PresentInDCI-ForDCIFormat1_2, etc.), or determined according to the number of bits X of the TCI field configured through the RRC signaling. For example, N - 1 = 2 X . For example, if the RRC configures the TCI field value length to be 3 bits, that is, X = 3, then it can be determined that 8 groups of TCI-states are activated by the MAC CE signaling, that is, N = 7.

[0487] It should also be understood that Figure 13 the TCI-state ID i,2 and the TCI-state ID i,1 can be the same or different. When the TCI-state ID i,2 and the TCI-state ID i,1 are the same, it means that actually only a single TCI-state is activated, that is, the i + 1-th TCI-state group only includes a single TCI-state, or in other words, the TCI field value i is only associated with one TCI-state (that is, the TCI-state ID i,1 ). In addition, the TCI-state ID i,2It can also be a specified special value or an invalid value. When the TCI-state ID i,2 is a specified special value or an invalid value, it indicates that actually only a single TCI-state is activated (i.e., the TCI-state ID i,1 ), that is, the (i + 1)-th TCI-state group only includes a single TCI-state (i.e., the TCI-state ID i,1 ), or in other words, the TCI field value i is only associated with one TCI-state (i.e., the TCI-state ID i,1 ).

[0488] In the above case 2, the above MAC CE signaling can be used to activate multiple TCI-state groups, and each TCI-state group can include one or two TCI-states. Among them, the first TCI-state (i.e., the TCI-state ID i,1 ) is mapped to the TCI field in the PDCCH corresponding to one TRP. If there is a second TCI-state (i.e., the TCI-state ID i,2 ), then the second TCI-state is mapped to the TCI field in the PDCCH corresponding to another TRP, where i ∈ {0, 1, …, N}. Specifically, the meanings of the R field, serving cell ID field, C i field, and S i field can be the same as those in case 1, which will not be elaborated here.

[0489] The TCI-state ID i,j represents the TCI-state corresponding to the TCI field value i in the PDCCH corresponding to the j-th TRP or the j-th CORESET group, where j ∈ {1, 2}. For example, the TCI-state ID i,1 represents the TCI-state corresponding to the TCI field value i in the PDCCH corresponding to the first TRP or the first CORESET group (i.e., the above first TCI-state), and the TCI-state ID i,2 represents the TCI-state corresponding to the TCI field value i in the PDCCH corresponding to the second TRP or the second CORESET group (i.e., the above second TCI-state).

[0490] Exemplarily, the TRP can be represented by a CORESET group. The network device can configure multiple CORESETs for the terminal device. Each CORESET can be configured with a group index (such as CORESETPoolIndex). The value of this group index (such as the value of CORESETPoolIndex) can be 0 or 1. When this group index is not configured, the default is 0. Therefore, not configuring this group index and configuring this group index to 0 are equivalent and interchangeable. CORESETs with the same above-mentioned group index value can be regarded as a group, corresponding to one TRP. Therefore, the above TCI-state association relationship can also be expressed as: TCI-state ID i,j represents the TCI-state corresponding to the TCI field value i in the PDCCH corresponding to the CORESET with the group index value of j - 1. For example, TCI-state ID i,1 represents the TCI-state corresponding to the TCI field value i in the PDCCH corresponding to the CORESET with the group index value of 0, TCI-state ID i,2 represents the TCI-state corresponding to the TCI field value i in the PDCCH corresponding to the CORESET with the group index value of 1. Or vice versa, TCI-state ID i,1 represents the TCI-state corresponding to the TCI field value i in the PDCCH corresponding to the CORESET with the group index value of 1, TCI-state ID i,2 represents the TCI-state corresponding to the TCI field value i in the PDCCH corresponding to the CORESET with the group index value of 0.

[0491] In the above two cases, the mapping method of TCI-state ID i,j is different. The terminal device can determine which case it is, so as to determine the mapping method of TCI-state ID i,j In this embodiment, the terminal device can determine the mapping method of TCI-state ID i,j in the following multiple ways, and this application embodiment does not limit this.

[0492] In a possible implementation, the terminal device can determine based on the grouping index value associated with the configured CORESET (such as CORESETPoolIndex). In the embodiments of the present application, each CORESET can be associated with a grouping index value, and this grouping index value can be a value explicitly configured by the network device (such as 0 or 1), or, in the case where the network device does not configure it, this grouping index value can be the default value 0. That the CORESET is associated with the grouping index value 0 can mean that the CORESET is configured with the grouping index value 0, or that the CORESET is not configured with the grouping index value. Exemplarily, if the grouping index values associated with each CORESET include two different values, for example, some CORESETs are associated with the grouping index value 0 and some CORESETs are associated with the grouping index value 1, then the terminal device can adopt the mapping method in the above case 2; conversely, if the grouping index values associated with each CORESET have only one value, for example, the grouping index values associated with each CORESET are all 0 (which can be replaced with: each CORESET is configured with the grouping index value 0; or replaced with: each CORESET is not configured with the above grouping index value; or replaced with: some CORESETs are configured with the grouping index value 0 and some CORESETs are not configured with the above grouping index value), or all the grouping index values associated with the CORESETs are 1 (which can be replaced with: each CORESET is configured with the grouping index value 1), then the terminal device can adopt the mapping method in case 1.

[0493] In another possible implementation, the terminal device can determine the TCI-state ID i,j through the information in the MAC CE (such as the above R field). Exemplarily, the value of the R field is used to indicate case 1 or case 2. Specifically, for example, R = 0 is used to indicate case 1, and R = 1 is used to indicate case 2; or, R = 0 is used to indicate case 2, and R = 1 is used to indicate case 1.

[0494] Note that the j in the above TCI-state ID i,j in the MAC CE can also be numbered starting from 0. At this time, the above TCI-state ID i,j can be replaced with TCI-state ID i,j-1 . For example, TCI-state ID i,1 is replaced with TCI-state ID i,0 , and TCI-state ID i,2 is replaced with TCI-state ID i,1 . The TCI-state ID i,jThe index i can also start from 1. In this case, the above TCI-state ID i,j can be replaced with TCI-state ID i+1,j . For example, the TCI-state ID 0,j is replaced with TCI-state ID 1,j , and the above TCI-state ID 1,j is replaced with TCI-state ID 2,j , and so on.

[0495] The number or upper limit of different TCI-states included in the above MAC CE format can be reported by the terminal device to the network device through the terminal capability reporting procedure. That is, the number of different TCI-states corresponding to two TRPs or two CORESET groups can be reported by the terminal device to the network device through the terminal capability reporting procedure, which will not be elaborated here.

[0496] It should be understood that there can be multiple different formats of MAC CE in the system. For example, the MAC CE used to activate the TCI-state in the R15 protocol (simply referred to as Format 1 for ease of description). This TCI-state uses a bitmap to indicate the TCI-states to be activated (the bit with a value of 1 indicates that the corresponding TCI-state is activated, and the activated TCI-states are associated with the respective TCI field values in ascending order of index and ascending order of field value), and up to 8 TCI-states can be activated. In addition, there is also the MAC CE format described in the above method (simply referred to as Format 2 for ease of description). In this way, the terminal device may receive multiple MAC CEs for activating the TCI-state of the PDSCH. In this case, one of the following methods can be adopted, and the embodiments of this application do not limit this.

[0497] 1. The terminal device can use the MAC CE signaling received most recently to determine the TCI-state corresponding to each TCI field value;

[0498] 2. The terminal device can select the MAC CE with a higher format priority based on the priorities of different formats of MAC CE and determine the TCI-state corresponding to each TCI field value.

[0499] Specifically, different formats may have different priorities. For example, the priority of Format 2 is higher than that of Format 1. When receiving a MAC CE of Format 2, the terminal device will refresh the TCI-states corresponding to the values of each TCI field, regardless of whether the TCI-state corresponding to the current TCI field value is activated by a MAC CE of Format 1 or a MAC CE of Format 2. When receiving a MAC CE of Format 1, if the TCI-state corresponding to the current TCI field value is activated by a MAC CE of Format 1, the terminal device will refresh the TCI-states corresponding to the values of each TCI field; if the TCI-state corresponding to the current TCI field value is activated by a MAC CE of Format 2, the terminal device cannot refresh the TCI-states corresponding to the values of each TCI field. The above priorities can also be reversed. For example, Format 1 has a higher priority than Format 2. When receiving a MAC CE of Format 1, the terminal device will refresh the TCI-states corresponding to the values of each TCI field, regardless of whether the TCI-state corresponding to the current TCI field value is activated by a MAC CE of Format 1 or a MAC CE of Format 2. When receiving a MAC CE of Format 2, if the TCI-state corresponding to the current TCI field value is activated by a MAC CE of Format 2, the terminal device will refresh the TCI-states corresponding to the values of each TCI field; if the TCI-state corresponding to the current TCI field value is activated by a MAC CE of Format 1, the terminal device cannot refresh the TCI-states corresponding to the values of each TCI field.

[0500] 3. The terminal device can report, through the capability reporting procedure, which type of MAC CE it supports. The network device will only send the MAC CE of the format supported by this terminal device. Alternatively, the terminal device can report, through the capability reporting procedure, which version of the protocol it supports (for example, reporting support for the R15 protocol or reporting support for the R16 protocol). The network device will only send the MAC CE of the format supported by the protocol corresponding to this version to this terminal device. For example, if the terminal device reports support for the R15 protocol, the network device will only send the above-mentioned MAC CE of Format 1 to the terminal device; if the terminal device reports support for the R16 protocol, the network device will only send the above-mentioned MAC CE of Format 2 to the terminal device.

[0501] 4. The protocol can specify that the network device cannot send both the MAC CE of Format 1 and the MAC CE of Format 2 to the terminal device.

[0502] It should be understood that the magnitudes of the sequence numbers of the above processes do not imply the order of execution. The order of execution of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0503] In the above, in combination with Figures 1 to 10 , the method for data transmission according to the embodiments of the present application has been described in detail. Next, in combination with Figures 11 to 12 , the apparatus for data transmission according to the embodiments of the present application will be described in detail.

[0504] Figure 11 FIG. 1100 shows an apparatus 1100 for data transmission provided by an embodiment of the present application. The apparatus 1100 may be a terminal device or a chip in a terminal device. The apparatus 1100 includes: a processing unit 1110 and a transceiver unit 1120.

[0505] In a possible implementation manner, the apparatus 1100 is used to execute each process and step corresponding to the terminal device in the above method 400.

[0506] The transceiver unit 1120 is configured to receive a first physical downlink control channel PDCCH, where the first PDCCH is used to schedule a first physical downlink shared channel PDSCH; and receive a downlink signal by using a first transmission configuration indication state TCI-state;

[0507] The processing unit 1110 is configured to obtain a time interval between the first PDCCH and the first PDSCH; and if the time interval is less than a preset threshold, obtain the first PDSCH from the downlink signal.

[0508] Optionally, the first TCI-state is a TCI-state included in a TCI-state group corresponding to a TCI field value that is the smallest or largest among one or more TCI-state groups including a TCI-state used by the first PDCCH; or, the first TCI-state is a TCI-state included in a TCI-state group corresponding to a TCI field value that is the smallest or largest among one or more TCI-state groups including a TCI-state activated by a CORESET with the smallest or largest index among the most recently received one or more CORESETs; where the TCI-state group corresponds to a TCI field value, and the TCI-state group includes one TCI-state or two TCI-states.

[0509] Optionally, if there is no TCI-state group including one or more TCI-states used by the first PDCCH, the first TCI-state is one of the TCI-states used by the first PDCCH; or, if there is no TCI-state group including one or more TCI-states activated by the CORESET with the smallest or largest index among the one or more recently received CORESETs, the first TCI-state is one of the TCI-states activated by the CORESET with the smallest or largest index among the one or more recently received CORESETs.

[0510] Optionally, in the case where no activation signaling is received, the first TCI-state is one of the TCI-states used by the first PDCCH; or, the first TCI-state is one of the TCI-states activated by the CORESET with the smallest or largest index among the one or more recently received CORESETs; wherein, the activation signaling is used to activate the TCI-state for PDSCH transmission.

[0511] Optionally, the processing unit 1110 is further configured to: if the time interval is greater than or equal to the preset threshold and the first PDCCH does not carry the TCI-state information, determine a second TCI-state, and receive the first PDSCH through the transceiver unit by using the second TCI-state.

[0512] Optionally, the second TCI-state is the TCI-state included in the TCI-state group with the smallest or largest corresponding TCI field value among the one or more TCI-state groups including one of the TCI-states used by the first PDCCH; or, the second TCI-state is the TCI-state included in the TCI-state group with the smallest or largest corresponding TCI field value among the one or more TCI-state groups including one of the TCI-states activated by the CORESET with the smallest or largest index among the one or more recently received CORESETs; wherein, each TCI-state group corresponds to a TCI field value, and each TCI-state group includes one TCI-state or two TCI-states.

[0513] Optionally, if there is no one or more TCI-state groups including one TCI-state used by the first PDCCH, the second TCI-state is one TCI-state used by the first PDCCH; or, if there is no one or more TCI-state groups including one TCI-state activated by the CORESET with the smallest or largest index among one or more recently received CORESETs, the second TCI-state is one TCI-state activated by the CORESET with the smallest or largest index among one or more recently received CORESETs.

[0514] Optionally, in the case where no activation signaling is received, the second TCI-state is one TCI-state used by the first PDCCH; or, the second TCI-state is one TCI-state activated by the CORESET with the smallest or largest index among one or more recently received CORESETs; wherein, the activation signaling is used to activate the TCI-state for PDSCH transmission.

[0515] Optionally, the transceiver unit 1120 is further configured to: receive a first signaling for activating one or more TCI-states for a CORESET, the first signaling including one or more of the following fields: a field for indicating the number of activated TCI-states, a field for indicating whether the number of activated TCI-states is single or multiple.

[0516] Optionally, the processing unit 1110 is further configured to: determine whether the network device uses two TCI-states to transmit the first PDSCH according to multiple currently activated TCI-states for PDSCH transmission; if there is at least one TCI-state group including two TCI-states among the multiple currently activated TCI-states for PDSCH transmission, determine that the network device uses two TCI-states to send the first PDSCH.

[0517] In a possible implementation manner, the apparatus 1100 is configured to execute each process and step corresponding to the terminal device in the foregoing method 700.

[0518] A transceiver unit 1120, configured to receive N physical downlink control channels (PDCCH), the N PDCCH are respectively used to schedule N physical downlink shared channels (PDSCH), N is an integer greater than 1; and, receive a downlink signal by using N transmission configuration indication states (TCI-state);

[0519] A processing unit 1110, configured to obtain a time interval between a first PDCCH among the N PDCCHs and a first PDSCH corresponding to the first PDCCH; and, if the time interval is less than a preset threshold, obtain the first PDSCH from downlink signals received from a first TCI-state corresponding to the first PDCCH among the N TCI-states.

[0520] Optionally, the first TCI-state is a currently active TCI-state in a CORESET with the smallest or largest index in a first control resource set CORESET group received in the most recent time slot, where the first CORESET group is a CORESET group composed of CORESETs having the same index as the CORESET corresponding to the first PDCCH.

[0521] Optionally, the index is an index related to a transmission site, where CORESETs corresponding to the same transmission site use the same index, and CORESETs corresponding to different transmission sites use different indexes.

[0522] Optionally, the transceiver unit 1120 is specifically configured to: receive downlink signals in a first time interval by using the first TCI-state, where the first time interval is the first symbol or the last symbol of the first PDCCH, or a time interval composed of K consecutive symbols starting from the first symbol after the first PDCCH, and K is the number of symbols corresponding to the preset threshold.

[0523] Optionally, the transceiver unit 1120 is specifically configured to: receive downlink signals in a first time interval by using the first TCI-state; receive downlink signals in a second time interval by using a second TCI-state among the N TCI-states; where the transmission time of the first PDCCH is before the transmission time of the second PDCCH, and a time interval composed of K consecutive symbols starting from a first moment overlaps with a time interval composed of K consecutive symbols starting from a second moment, the first time interval is the first half of the time interval composed of the first moment to a third moment, the second time interval is the second half of the time interval composed of the first moment to the third moment, the first moment is the first symbol or the last symbol of the first PDCCH, or the first symbol after the first PDCCH, the second moment is the first symbol or the last symbol of the second PDCCH, or the first symbol after the second PDCCH, and the third moment is the Kth symbol after the second moment.

[0524] In a possible implementation, the apparatus 1100 is configured to perform each of the processes and steps corresponding to the terminal device in the above method 500.

[0525] A transceiver unit 1120, configured to receive downlink control information DCI, where the DCI is used to schedule a physical downlink shared channel PDSCH; receive the PDSCH according to the DCI; wherein, when a preset condition is satisfied, the DCI and the PDSCH satisfy one or more of the following: the time interval between the reception time of the DCI and the PDSCH is greater than or equal to a preset threshold; or, the DCI includes a transmission configuration indication TCI field value; the preset condition includes one or more of the following: the cell corresponding to the physical downlink control channel PDCCH that transmits the DCI is different from the cell corresponding to the PDSCH; the subcarrier spacing used by the DCI and the PDSCH is different; the transmission configuration indication state TCI-state for PDSCH transmission is not activated in the cell corresponding to the PDSCH; the control resource set CORESET is not configured in the cell corresponding to the PDSCH; the cell corresponding to the DCI uses a frequency in frequency range FR1 for transmission; the TCI-state including quasi-co-location QCL-TypeD information is not configured in the cell corresponding to the DCI.

[0526] Optionally, the preset condition includes: the cell corresponding to the PDCCH that transmits the DCI is different from the cell corresponding to the PDSCH; the TCI-state for PDSCH transmission is not activated in the cell corresponding to the PDSCH; and, the subcarrier spacing used by the DCI and the PDSCH is different.

[0527] Optionally, the preset condition includes: the TCI-state for PDSCH transmission is not activated in the cell corresponding to the PDSCH; and, the subcarrier spacing used by the DCI and the PDSCH is different.

[0528] In a possible implementation, the apparatus 1100 is configured to perform each of the processes and steps corresponding to the terminal device in the above method 500.

[0529] A transceiver unit 1120, configured to receive downlink control information DCI, where the DCI is used to schedule a physical downlink shared channel PDSCH; receive the PDSCH by using a transmission configuration indication state TCI-state; wherein, when a preset condition is satisfied, the TCI-state is the TCI-state used by a physical downlink control channel PDCCH that transmits the DCI, and the preset condition includes one or more of the following: a cell corresponding to the PDCCH that transmits the DCI is different from a cell corresponding to the PDSCH; a time interval between the DCI and a reception time of the PDSCH is greater than or equal to a preset threshold; the DCI does not include a TCI field value; a cell corresponding to the DCI transmits by using a frequency in a frequency range FR2; the cell corresponding to the DCI is configured with a TCI-state including quasi-co-location QCL-TypeD information; a TCI-state for PDSCH transmission is not activated in the cell corresponding to the PDSCH; or, a control resource set CORESET is not configured in the cell corresponding to the PDSCH.

[0530] Optionally, the preset condition includes: a cell corresponding to the PDCCH that transmits the DCI is different from a cell corresponding to the PDSCH; a cell corresponding to the DCI transmits by using a frequency in a frequency range FR2; the DCI does not include a TCI field value; and a time interval between the DCI and a reception time of the PDSCH is greater than or equal to a preset threshold.

[0531] In a possible implementation, the apparatus 1100 is configured to execute each process and step corresponding to the terminal device in the foregoing method 500.

[0532] A transceiver unit 1120 is configured to receive downlink control information (DCI), where the DCI is used to schedule a physical downlink shared channel (PDSCH); receive the PDSCH using a transmission configuration indication state (TCI-state); where, when a preset condition is met, the TCI-state is the TCI-state activated by the CORESET with the smallest index among at least one CORESET that is most recently listened to in the currently activated bandwidth part (BWP) of the cell corresponding to the DCI of the terminal device, and the preset condition includes one or more of the following: the cell corresponding to the physical downlink control channel (PDCCH) transmitting the DCI is different from the cell corresponding to the PDSCH; the time interval between the reception time of the DCI and the PDSCH is less than a preset threshold; the cell corresponding to the DCI uses a frequency in frequency range FR2 for transmission; the cell corresponding to the DCI is configured with a TCI-state including quasi-co-location (QCL)-TypeD information; the TCI-state for PDSCH transmission is not activated in the cell corresponding to the PDSCH; the cell corresponding to the PDSCH is not configured with a control resource set (CORESET).

[0533] Optionally, the preset condition includes: the cell corresponding to the PDCCH transmitting the DCI is different from the cell corresponding to the PDSCH; the cell corresponding to the DCI uses a frequency in frequency range FR2 for transmission; the time interval between the reception time of the DCI and the PDSCH is less than a preset threshold; and the TCI-state for PDSCH transmission is not activated in the cell corresponding to the PDSCH.

[0534] In a possible implementation, the apparatus 1100 is configured to perform each process and step corresponding to the terminal device in the above method 600.

[0535] A transceiver unit 1120 is configured to receive a first signaling, where the first signaling is used to activate a plurality of transmission configuration indication state (TCI state) groups, and each TCI state group in the plurality of TCI state groups includes one or two TCI states.

[0536] A processing unit 1110 is configured to determine a mapping manner between each TCI state and a TCI field value according to configuration information of a control resource set (CORESET) or indication information in the first signaling.

[0537] Optionally, the mapping method includes a first mapping method. Under the first mapping method, among the multiple TCI state groups, the j-th TCI state in the i-th TCI state group represents the j-th TCI state corresponding to the TCI field value i, where i is an integer greater than or equal to 0, and j is a positive integer.

[0538] Optionally, the mapping method includes a second mapping method. Under the second mapping method, among the multiple TCI state groups, the j-th TCI state in the i-th TCI state group represents the TCI state corresponding to the TCI field value i in the PDCCH corresponding to the CORESET with the grouping index value of j - 1, where i is an integer greater than or equal to 0, and j is a positive integer.

[0539] Optionally, each CORESET is associated with a grouping index value, and the CORESETs with the same grouping index value are grouped as one group.

[0540] Optionally, when the grouping index values of the configured CORESETs include two different values in total, the mapping method is the second mapping method; or, when the grouping index values of the configured CORESETs include one value in total, the mapping method is the first mapping method.

[0541] Optionally, when the value of the first field in the first signaling is 0, the mapping method is the first mapping method; or, when the value of the first field in the first signaling is 1, the mapping method is the second mapping method.

[0542] Optionally, when the value of the first field in the first signaling is 1, the mapping method is the first mapping method; or, when the value of the first field in the first signaling is 0, the mapping method is the second mapping method.

[0543] Optionally, the first field is the field composed of the first bit in the first signaling.

[0544] Optionally, in the first signaling, before the field corresponding to the last TCI state in the i-th TCI state group among the multiple TCI state groups, there is a second field, and the second field is used to indicate whether there is an (i + 1)-th TCI state group among the multiple TCI state groups, where i is an integer greater than or equal to 0.

[0545] Optionally, the transceiver unit 1120 is further configured to: send terminal capability parameters, and the terminal capability parameters include one or more of the following:

[0546] The first capability parameter is used to indicate the upper limit of the number of different TCI states corresponding to the CORESET associated with one of the two different grouping index values when the configured CORESET is associated with two different grouping index values;

[0547] The second capability parameter is used to indicate the upper limit of the number of different TCI states corresponding to the configured CORESET when the configured CORESET is associated with two different grouping index values;

[0548] The third capability parameter is used to indicate the upper limit of the number of different TCI states corresponding to the configured CORESET when the configured CORESET is associated with the same grouping index value;

[0549] The fourth capability parameter is used to indicate the upper limit of the number of different TCI states among the TCI states indicated by the first signaling;

[0550] The fifth capability parameter is used to indicate the upper limit of the number of different TCI states among the TCI states indicated by the first signaling when the configured CORESET is associated with two different grouping index values; or,

[0551] The sixth capability parameter is used to indicate the upper limit of the number of different TCI states among the TCI states indicated by the first signaling when the configured CORESET is associated with the same grouping index value.

[0552] It should be understood that the apparatus 1100 here is embodied in the form of functional units. The term "unit" here may refer to an application-specific integrated circuit (ASIC), an electronic circuit, a processor (such as a shared processor, a dedicated processor, or a group of processors, etc.) for executing one or more software or firmware programs, and a memory, a combined logic circuit, and / or other suitable components that support the described functions. In an alternative example, those skilled in the art can understand that the apparatus 1100 can specifically be the terminal device in the above embodiments, and the apparatus 1100 can be used to execute the respective processes and / or steps corresponding to the terminal device in the above method embodiments. To avoid repetition, it will not be elaborated here. In another alternative example, those skilled in the art can understand that the apparatus 1100 can specifically be the network device in the above embodiments, and the apparatus 1100 can be used to execute the respective processes and / or steps corresponding to the network device in the above method embodiments. To avoid repetition, it will not be elaborated here.

[0553] The apparatus 1100 of each of the above solutions has the function of implementing the corresponding steps performed by the terminal device or the network device in the above method; the 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. For example, the above transceiver unit 1120 may include a sending unit and a receiving unit. The sending unit may be used to implement each step and / or process corresponding to the above transceiver unit for performing a sending action, and the receiving unit may be used to implement each step and / or process corresponding to the above transceiver unit for performing a receiving action. The sending unit may be replaced by a transmitter, and the receiving unit may be replaced by a receiver, respectively performing the transceiver operations and related processing operations in each method embodiment.

[0554] In an embodiment of the present application, Figure 11 the apparatus 1100 in may also be a chip or a chip system, for example: a system on chip (SoC). Correspondingly, the transceiver unit 1120 may be a transceiver circuit of the chip, which is not limited herein.

[0555] Figure 12 Figure 9 shows another apparatus 1200 for data transmission provided by an embodiment of the present application. The apparatus 1200 includes a processor 1210, a transceiver 1220, and a memory 1230. Among them, the processor 1210, the transceiver 1220, and the memory 1230 communicate with each other through an internal connection path. The memory 1230 is used to store instructions, and the processor 1210 is used to execute the instructions stored in the memory 1230 to control the transceiver 1220 to send signals and / or receive signals.

[0556] In a possible implementation manner, the apparatus 1200 is used to execute each process and step corresponding to the terminal device in the above method 400.

[0557] Among them, the processor 1210 is used to: receive a first physical downlink control channel PDCCH through the transceiver 1220, where the first PDCCH is used to schedule a first physical downlink shared channel PDSCH; and, receive a downlink signal by using a first transmission configuration indication state TCI-state; obtain a time interval between the first PDCCH and the first PDSCH; and, if the time interval is less than a preset threshold, obtain the first PDSCH from the downlink signal.

[0558] In a possible implementation manner, the apparatus 1200 is used to execute each process and step corresponding to the terminal device in the above method 700.

[0559] Wherein, the processor 1210 is configured to: receive N physical downlink control channels (PDCCHs) via the transceiver 1220, where the N PDCCHs are respectively used to schedule N physical downlink shared channels (PDSCHs), and N is an integer greater than 1; receive downlink signals using N transmission configuration indication states (TCI-states); obtain the time interval between a first PDCCH among the N PDCCHs and a first PDSCH corresponding to the first PDCCH; and, if the time interval is less than a preset threshold, obtain the first PDSCH from the downlink signals received using the first TCI-state among the N TCI-states, which corresponds to the first PDCCH.

[0560] In a possible implementation, the apparatus 1200 is configured to perform each process and step corresponding to the terminal device in the above method 500, which will not be elaborated herein.

[0561] In a possible implementation, the apparatus 1200 is configured to perform each process and step corresponding to the terminal device in the above method 600, which will not be elaborated herein.

[0562] It should be understood that the apparatus 1200 may specifically be the terminal device or network device in the above embodiments, and may be configured to perform each step and / or process corresponding to the terminal device or network device in the above method embodiments. Optionally, the memory 1230 may include a read-only memory and a random access memory, and provide instructions and data to the processor. A part of the memory may further include a non-volatile random access memory. For example, the memory may further store information about the device type. The processor 1210 may be configured to execute the instructions stored in the memory, and when the processor 1210 executes the instructions stored in the memory, the processor 1210 is configured to perform each step and / or process of the above method embodiments corresponding to the terminal device or network device. The transceiver 1220 may include a transmitter and a receiver. The transmitter may be configured to implement each step and / or process corresponding to the transceiver for performing a transmission action, and the receiver may be configured to implement each step and / or process corresponding to the transceiver for performing a reception action.

[0563] It should be understood that in the embodiments of the present application, the processor of the above apparatus may be a central processing unit (CPU), and the processor may 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 gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor, or the processor may also be any conventional processor, etc.

[0564] In the implementation process, the steps of the above method can be completed by the integrated logic circuit of the hardware in the processor or the instructions 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 being executed and completed by the hardware processor, or executed and completed by the combination of the hardware and software units in the processor. The software unit can be located in a mature storage medium in the art such as random access memory, flash memory, read-only memory, programmable read-only memory, or electrically erasable programmable memory, registers, etc. This storage medium is located in the memory, and the processor executes the instructions in the memory and combines its hardware to complete the steps of the above method. To avoid repetition, it will not be described in detail here.

[0565] Those of ordinary skill in the art can realize that, in combination with the method steps and units described in the embodiments disclosed herein, they can be implemented by electronic hardware, computer software, or a combination of the two. To clearly illustrate the interchangeability of hardware and software, the steps and components of each embodiment have been generally described according to functions in the above description. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Those of ordinary skill in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present application.

[0566] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices, and units described above can refer to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0567] In several embodiments provided in the present application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there can be other division methods in actual implementation. For example, multiple units 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 coupling, direct coupling, or communication connection can be an indirect coupling or communication connection through some interfaces, devices, or units, and can also be in an electrical, mechanical, or other form of connection.

[0568] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they can be located in one place, or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiments of the present application.

[0569] In addition, in each embodiment of the present application, the functional units can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

[0570] If the above integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several 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 methods described in each embodiment of the present application. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs that can store program codes.

[0571] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method for data transmission, characterized in that Including: Receiving downlink control information DCI; Receiving a physical downlink shared channel PDSCH corresponding to the DCI; Wherein, when the time interval between the DCI and the PDSCH is less than a preset threshold, and at least one transmission configuration indication state TCI-state including QCL information of type D is configured in the serving cell corresponding to the PDSCH, and at least one transmission configuration indication TCI field value indicates two TCI-states, the PDSCH is received using two default TCI-states.

2. The method according to claim 1, wherein The two default TCI-states are the two TCI-states corresponding to the smallest TCI field value among the TCI field values corresponding to the two TCI-states.

3. The method according to claim 1 or 2, characterized in that, Wherein, When the PDSCH is transmitted using a frequency in frequency range FR2, the PDSCH is received using the two default TCI-states.

4. The method according to claim 1 or 2, characterized in that When the terminal capability information indicates support for transmitting the PDSCH using two default TCI-states, the PDSCH is received using the two default TCI-states.

5. The method according to claim 1 or 2, characterized in that, When the time interval between the DCI and the PDSCH is less than a preset threshold, and at least one TCI-state including QCL information of type D is configured in the serving cell corresponding to the PDSCH, and all TCI field values correspond to a single TCI-state, the PDSCH is received using a single default TCI-state.

6. The method according to claim 5, wherein The single default TCI-state is the TCI-state activated by the CORESET with the smallest index among at least one control resource set CORESET heard by the terminal device in the most recent first time slot, and the first time slot refers to the time slot in which one or more CORESETs are heard in the active bandwidth part BWP of the serving cell.

7. The method according to claim 5, wherein When the terminal capability information indicates non-support for transmitting the PDSCH using two default TCI-states, the PDSCH is received using the single default TCI-state.

8. The method according to claim 1 or 2, characterized in that, The TCI field value is the codepoint of the TCI field in the DCI.

9. A method for data transmission, characterized in that, Including: Transmitting downlink control information DCI; Transmitting a physical downlink shared channel PDSCH corresponding to the DCI; Wherein, when the time interval between the DCI and the PDSCH is less than a preset threshold, and at least one transmission configuration indication state TCI-state including QCL information of type D is configured in the serving cell corresponding to the PDSCH, and at least one transmission configuration indication TCI field value indicates two TCI-states, the PDSCH is transmitted using two default TCI-states.

10. The method according to claim 9, wherein The two default TCI-states are the two TCI-states corresponding to the smallest TCI field value among the TCI field values corresponding to the two TCI-states.

11. The method according to claim 9 or 10, characterized in that, Wherein, When the PDSCH is transmitted using a frequency in frequency range FR2, the two default TCI-states are used to transmit the PDSCH.

12. The method according to claim 9 or 10, characterized in that, When the terminal capability information indicates support for transmitting the PDSCH using two default TCI-states, the two default TCI-states are used to transmit the PDSCH.

13. The method according to claim 9 or 10, wherein when the time interval between the DCI and the PDSCH is less than a preset threshold, and at least one TCI-state including QCL information of Type D is configured in the serving cell corresponding to the PDSCH, and all TCI field values correspond to a single TCI-state, the single default TCI-state is used to transmit the PDSCH.

14. The method according to claim 13, wherein The single default TCI-state is the TCI-state activated by the CORESET with the smallest index among at least one control resource set CORESET heard by the terminal device in the most recent first time slot, and the first time slot refers to the time slot in which one or more CORESETs are heard in the active bandwidth part BWP of the serving cell.

15. The method according to claim 13, wherein When the terminal capability information indicates non-support for transmitting the PDSCH using two default TCI-states, the single default TCI-state is used to transmit the PDSCH.

16. The method according to claim 9 or 10, characterized in that, The TCI field value is the codepoint of the TCI field in the DCI.

17. A data transmission device, characterized in that, Including: a transceiver unit The transceiver unit is configured to: receive downlink control information DCI; and receive the downlink shared channel PDSCH corresponding to the DCI; wherein, when the time interval between the DCI and the PDSCH is less than a preset threshold, and at least one transmission configuration indication state TCI-state including quasi-co-located QCL information of Type D is configured in the serving cell corresponding to the PDSCH, and at least one transmission configuration indication TCI field value indicates two TCI-states, the two default TCI-states are used to receive the PDSCH.

18. The device according to claim 17, characterized in that, The two default TCI-states are the two TCI-states corresponding to the smallest TCI field value among the TCI field values corresponding to the two TCI-states.

19. The device according to claim 17 or 18, characterized in that Wherein when the PDSCH is transmitted using a frequency in frequency range FR2, the transceiver unit uses the two default TCI-states to receive the PDSCH.

20. The device according to claim 17 or 18, characterized in that, When the terminal capability information indicates support for transmitting the PDSCH using two default TCI-states, the transceiver unit uses the two default TCI-states to receive the PDSCH.

21. The apparatus according to claim 17 or 18, wherein When the time interval between the DCI and the PDSCH is less than a preset threshold, and at least one transmission configuration indication (TCI)-state including QCL information of type D is configured in the serving cell corresponding to the PDSCH, and all TCI field values correspond to a single TCI-state, the transceiver unit receives the PDSCH using a single default TCI-state.

22. The device according to claim 21, characterized in that, The single default TCI-state is the TCI-state activated by the CORESET with the smallest index among at least one control resource set (CORESET) detected in the most recent first time slot by the terminal device, where the first time slot refers to the time slot in which one or more CORESETs are detected in the activated bandwidth part (BWP) of the serving cell.

23. The device according to claim 21, characterized in that, When the terminal capability information indicates that it does not support transmitting the PDSCH using two default TCI-states, the transceiver unit receives the PDSCH using the single default TCI-state.

24. The device according to claim 17 or 18, characterized in that The TCI field value is the code point of the TCI field in the DCI.

25. A data transmission device, characterized in that, Comprising: A transceiver unit, wherein the transceiver unit is configured to: transmit downlink control information (DCI); and transmit the physical downlink shared channel (PDSCH) corresponding to the DCI; wherein, when the time interval between the DCI and the PDSCH is less than a preset threshold, and at least one transmission configuration indication (TCI)-state including quasi-co-location (QCL) information of type D is configured in the serving cell corresponding to the PDSCH, and at least one transmission configuration indication (TCI) field value indicates two TCI-states, the two default TCI-states are used to transmit the PDSCH.

26. The device according to claim 25, characterized in that, The two default TCI-states are the two TCI-states corresponding to the smallest TCI field value among the TCI field values corresponding to the two TCI-states.

27. The device according to claim 25 or 26, characterized in that, Wherein, when the PDSCH is transmitted using a frequency in frequency range 2 (FR2), the transceiver unit transmits the PDSCH using the two default TCI-states.

28. The device according to claim 25 or 26, wherein When the terminal capability information indicates that it supports transmitting the PDSCH using two default TCI-states, the transceiver unit transmits the PDSCH using the two default TCI-states.

29. The apparatus according to claim 25 or 26, characterized in that when the time interval between the DCI and the PDSCH is less than a preset threshold, and at least one transmission configuration indication (TCI)-state including QCL information of type D is configured in the serving cell corresponding to the PDSCH, and all TCI field values correspond to a single TCI-state, the transceiver unit transmits the PDSCH using a single default TCI-state.

30. The device according to claim 29, wherein, The single default TCI-state is the TCI-state activated by the CORESET with the smallest index among at least one control resource set (CORESET) detected by the terminal device in the most recent first time slot, and the first time slot refers to the time slot in which one or more CORESETs are detected in the active bandwidth part (BWP) of the serving cell.

31. The device according to claim 29, wherein, When the terminal capability information indicates that two default TCI-states are not supported for transmitting the PDSCH, the transceiver unit transmits the PDSCH using the single default TCI-state.

32. The device according to claim 25 or 26, characterized in that The TCI field value is the code point of the TCI field in the DCI.

33. A device for data transmission, characterized in that, It includes: A processor, a memory, and a transceiver; The transceiver is configured to receive or transmit signals; The memory is configured to store program code or instructions; The processor is configured to execute the program code or instructions in the memory to implement the method according to any one of claims 1 to 16.

34. A device for data transmission, characterized in that, It includes: A processor, the processor is coupled to the memory, and the processor is configured to execute the computer program or instructions in the memory to implement the method according to any one of claims 1 to 16.

35. A device for data transmission, characterized in that, It includes: A memory and a processor; The memory is used to store computer programs or instructions, and the processor is used to execute the computer programs or instructions in the memory to implement the method according to any one of claims 1 to 16.

36. A computer-readable medium for storing a computer program or instructions, characterized in that, When the computer program or instructions are run, the computer is caused to execute the method according to any one of claims 1 to 16.

37. A computer program product including computer program code or instructions, characterized in that, When the computer program code or instructions are run, the computer is caused to execute the method according to any one of claims 1 to 16.

38. A chip, characterized in that, It includes: A processor and an input / output interface; the input / output interface is coupled to the processor; The processor is configured to execute computer programs or instructions to implement the method according to any one of claims 1 to 16.

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