Communication method and communication apparatus

Abstract

The present application provides a communication method and a communication apparatus. The method comprises: receiving first information, wherein the first information is used for indicating whether a network device cancels interference between a plurality of transport layers, the plurality of transport layers corresponding to different codewords; or, the first information is used for indicating a codeword associated with first channel state information, the first channel state information being used for precoding downlink information; and receiving the downlink information on the basis of the first information. By means of the exchange of the first information, a terminal device and the network device can reach a consistent understanding of a precoding scheme of the network device, thereby providing support for determining an interference cancellation scheme of the terminal device and a downlink reception strategy, and facilitating improvement of downlink reception performance.

Description

Communication method and communication apparatus

[0001] The present application claims priority from the Chinese patent application No. 202411393393.7 filed on September 30, 2024, and entitled "Communication method and communication apparatus", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present application relates to the field of communication technology, and more particularly, to a communication method and a communication apparatus. BACKGROUND

[0003] Generally, multi-stream transmission can effectively improve spectrum efficiency. The number of transmission streams can also be referred to as the number of transmission layers. When the downlink transmission adopts multi-stream transmission, some factors can affect the reception performance of the downlink signal.

[0004] For example, there is a certain interference between the multiple transmission layers corresponding to different code words, thereby causing the system performance to decline. Or, there is a certain interference between the multiple sub-receivers of the terminal device, because different code words correspond to different sub-receivers.

[0005] For another example, when a single code word can support multi-stream transmission, if the terminal device adopts an inappropriate code word to receive the downlink signal, the reception performance of the downlink signal will be affected. Or, when a single sub-receiver of the terminal device can support multi-stream transmission, if the terminal device adopts an inappropriate receiver to receive the downlink signal, the reception performance of the downlink signal will be affected. SUMMARY

[0006] The present application provides a communication method and a communication apparatus, which helps to improve the reception performance of the downlink signal.

[0007] In a first aspect, a communication method is provided, which includes: receiving first information, the first information being used to indicate whether a network device eliminates interference between multiple transmission layers, the multiple transmission layers corresponding to different code words; and receiving the downlink information based on the first information.

[0008] Exemplarily, the communication method can be implemented by a terminal device, or by a component inside the terminal device, such as a processor, a circuit, a chip or a chip system.

[0009] In the case that the terminal device has multiple sub-receivers, different sub-receivers usually correspond to different code words, or different sub-receivers usually adopt different code words for signal transmission and reception. Therefore, the first information can be used to indicate whether the network device eliminates interference between multiple sub-receivers.

[0010] The multiple transmission layers corresponding to different code words can be understood as transmission layers corresponding to different sub-receivers. In the case that the sub-receiver includes multiple antennas, one sub-receiver can correspond to multiple transmission layers. In this case, the multiple transmission layers corresponding to different code words can be replaced by multiple transmission layer sets corresponding to different code words, wherein different transmission layer sets in the multiple transmission layer sets correspond to different code words. The transmission layers included in the transmission layer set mentioned herein can correspond to the same sub-receiver.

[0011] Exemplarily, the first information can be used to indicate a precoding scheme of the network device. In some embodiments, the precoding scheme mentioned above can be used to indicate an interference cancellation scheme of the network device, or in other words, to indicate whether the network device cancels the interference between the multiple transmission layers (the multiple transmission layers correspond to different code words). In other words, the precoding scheme can be used to indicate whether the network device cancels the interference between the multiple sub-receivers of the terminal device.

[0012] If the terminal device cannot obtain the precoding scheme of the network device, the terminal device cannot determine which interference between the multiple transmission layers needs to be cancelled. Then there will be the following two cases: one is that part of the interference between the transmission layers is not cancelled, which will affect the downlink reception performance; the other is that the terminal device repeatedly cancels the interference between the transmission layers, which will increase unnecessary overhead.

[0013] Therefore, in the embodiments of the present application, through the interaction of the first information, the terminal device and the network device can reach a consistent understanding of the precoding scheme of the network device, which provides support for determining the interference cancellation scheme of the terminal device. For example, the terminal device can cancel the interference between the multiple transmission layers which is not cancelled by the network device, thereby helping to avoid the influence of the interference on the downlink reception performance and helping to avoid unnecessary overhead on the terminal device side.

[0014] In some embodiments, the multiple transmission layers include a first transmission layer and a second transmission layer, the interference of the first transmission layer to the second transmission layer is a first interference, the interference of the second transmission layer to the first transmission layer is a second interference, and the first information is used to indicate one or more of the following: the network device does not cancel the first interference and the second interference; the network device cancels the first interference; the network device cancels the second interference; or the network device cancels both the first interference and the second interference.

[0015] Exemplarily, the first information can be used to indicate the precoding scheme of the network device through different indexes, which is simple to implement.

[0016] Exemplarily, the first information can be implemented through multiple bits (or a bit sequence).

[0017] As an example, each bit corresponds to one interference cancellation manner. Different values of each bit are used to indicate whether the interference cancellation manner corresponding to the bit is adopted.

[0018] As an example, the multiple values of the bit sequence correspond to the multiple interference cancellation manners one by one.

[0019] Exemplarily, the receiving the downlink information based on the first information can include: if the first information indicates that the network device cancels the first interference, the terminal device can cancel the second interference when receiving the downlink information; if the first information indicates that the network device cancels the second interference, the terminal device can cancel the first interference when receiving the downlink information; if the first information indicates that the network device cancels both the first interference and the second interference, the terminal device does not need to cancel the first interference and the second interference when receiving the downlink information; if the first information indicates that the network device does not cancel both the first interference and the second interference, the terminal device can cancel both the first interference and the second interference when receiving the downlink information.

[0020] In some embodiments, the first information includes a demodulation reference signal (DMRS) port index, and the DMRS port index is used to indicate whether the network device cancels the interference between the multiple transmission layers.

[0021] That is, the first information can multiplex a field in the existing signaling, such as the DMRS port index, without defining a new signaling or field, thereby helping to reduce the degree of change of the protocol by the scheme provided in the embodiments of the present application, and helping to reduce the signaling overhead, so as to facilitate implementation.

[0022] In some embodiments, one DMRS port group includes multiple DMRS ports, one DMRS port group corresponds to multiple DMRS port indexes, and the multiple DMRS port indexes correspond to multiple interference cancellation manners one by one, and the interference cancellation manner is a manner in which the network device cancels the interference between the multiple transmission layers.

[0023] Exemplarily, one DMRS port group can correspond to multiple DMRS port indexes in the case that other parameters are the same, such as the case that the code word enabling condition is the same, the DMRS type is the same, and the maxLength is the same. In this case, one DMRS port index can be used to indicate one precoding scheme of the network device, or multiple DMRS port indexes correspond to multiple precoding schemes one by one. In other words, one DMRS port index can be used to indicate one interference cancellation manner, or multiple DMRS port indexes correspond to multiple interference cancellation manners one by one.

[0024] In this way, through the interaction of the first information, the terminal device can not only obtain the precoding scheme of the network device, but also obtain the DMRS port number, thereby helping to reduce the signaling overhead.

[0025] In some embodiments, before the receiving the first information, the method further includes: sending capability information of the terminal device, the capability information being used to indicate the capability of the terminal device to cancel the interference between the multiple transmission layers.

[0026] In other words, the capability information of the terminal device can be used to indicate the capability of the terminal device to cancel the interference between multiple sub-receivers.

[0027] Still taking the example of the multiple transmission layers including the first transmission layer and the second transmission layer as mentioned above, the capability information can indicate that the terminal device has one or more of the following capabilities: the capability to cancel the first interference; the capability to cancel the second interference; the capability to cancel the first interference and the second interference; or the terminal device does not have the capability to cancel the first interference and the second interference.

[0028] Alternatively, the capability information can be used to indicate whether the terminal device has the capability to cancel all the interference between the multiple sub-receivers. In the case that the terminal device does not have the capability to cancel all the interference between the multiple sub-receivers, the capability information (or other information) can be used to indicate which interference the terminal device can cancel or which interference the terminal device cannot cancel.

[0029] In some embodiments, in the case that the first condition is met, the first information can be used to indicate whether the network device cancels the interference between the multiple transmission layers, or in other words, the first information is used to indicate whether the network device cancels the interference between the multiple receivers of the terminal device; in the case that the first condition is not met, the first information can be used to indicate the code word associated with the first channel state information.

[0030] Exemplarily, the first condition can be related to the number of transmission layers, or in other words, the first condition can be related to the rank, or in other words, the first condition can be related to the number of antennas of the multiple sub-receivers of the terminal device.

[0031] For example, the first condition can be that the number of transmission layers is greater than A, or the first condition can be that the number of transmission layers is greater than or equal to A.

[0032] In some embodiments, in the case that the number of transmission layers between the network device and the terminal device is greater than A, the first information is used to indicate whether the network device performs interference cancellation between the multiple transmission layers; and / or in the case that the number of transmission layers between the network device and the terminal device is less than or equal to A, the first information is used to indicate a code word associated with the first channel state information; wherein A is a positive integer.

[0033] In some embodiments, the number of transmission layers corresponding to the first code word is n, the number of transmission layers corresponding to the second code word is m, and the A is the maximum of m and n. Or, A can be max(m, n). For example, the terminal device includes two sub-receivers (2R+4R), i.e., m is 2 and n is 4, and then A can be 4.

[0034] Exemplarily, the terminal device supports independent reception of the first sub-receiver and supports independent reception of the second sub-receiver, and A can be the maximum of m and n.

[0035] In some embodiments, the first information is carried in radio resource control (RRC) signaling or downlink control information (DCI).

[0036] Exemplarily, the index of the precoding scheme (i.e., the first information) can be carried in RRC. In this way, after the precoding scheme is configured to the terminal device through RRC, the network device performs interference cancellation according to the precoding scheme.

[0037] Exemplarily, the first information is carried in DCI, and the precoding scheme can be dynamically adjusted according to channel changes, such as different precoding schemes can be used at different times, thereby helping to improve the flexibility of interference cancellation. For example, the DMRS port field (i.e., the first information) can be carried in DCI.

[0038] In a second aspect, a communication method is provided, which includes: determining first information, the first information being used to indicate whether a network device performs interference cancellation between multiple transmission layers of a terminal device, the multiple transmission layers corresponding to different code words; and sending the first information.

[0039] Exemplarily, the communication method can be implemented by a network device, or by a component inside the network device, such as a processor, a circuit, a chip, or a chip system.

[0040] Exemplarily, the first information can be used to indicate a precoding scheme of the network device. In some embodiments, the precoding scheme can be used to indicate an interference cancellation scheme of the network device, or to indicate whether the network device cancels the interference between multiple transmission layers (the multiple transmission layers correspond to different codewords).

[0041] If the terminal device cannot obtain the precoding scheme of the network device, the terminal device cannot determine which interference between the multiple transmission layers needs to be cancelled. Then there will be two cases: one is that part of the interference between the transmission layers is not cancelled, which will affect the downlink reception performance; the other is that the terminal device repeatedly cancels the interference between the transmission layers, which will increase unnecessary overhead.

[0042] Therefore, in the embodiments of the present application, through the interaction of the first information, the terminal device and the network device can reach a common understanding of the precoding scheme of the network device, which provides support for determining the interference cancellation scheme of the terminal device. For example, the terminal device can cancel the interference between the multiple transmission layers which is not cancelled by the network device, thereby helping to avoid the impact of the interference on the downlink reception performance, and helping to avoid unnecessary overhead on the terminal device side.

[0043] In some embodiments, the multiple transmission layers include a first transmission layer and a second transmission layer, the interference of the first transmission layer to the second transmission layer is a first interference, the interference of the second transmission layer to the first transmission layer is a second interference, and the first information is used to indicate one or more of the following: the network device does not cancel the first interference and the second interference; the network device cancels the first interference; the network device cancels the second interference; or the network device cancels both the first interference and the second interference.

[0044] Exemplarily, the first information can be used to indicate the precoding scheme of the network device through different indexes, which is simple to implement.

[0045] Exemplarily, the first information can be implemented through multiple bits (or a bit sequence).

[0046] As an example, each bit corresponds to an interference cancellation mode. Different values of each bit are used to indicate whether the interference cancellation mode corresponding to the bit is adopted. As another example, multiple values of the bit sequence correspond to multiple interference cancellation modes one by one.

[0047] In some embodiments, the first information comprises a demodulation reference signal (DMRS) port index, and the DMRS port index is used to indicate whether the network device cancels the interference between the multiple transmission layers.

[0048] That is, the first information can multiplex a field in existing signaling, such as a DMRS port index, without defining new signaling or fields, thereby helping to reduce the degree of modification of the protocol by the scheme provided in the embodiments of the present application, and helping to reduce signaling overhead, so as to facilitate implementation.

[0049] In some embodiments, one DMRS port group comprises multiple DMRS ports, one DMRS port group corresponds to multiple DMRS port indexes, and the multiple DMRS port indexes correspond to multiple interference cancellation modes one by one, and the interference cancellation mode is a mode in which the network device cancels the interference between the multiple transmission layers.

[0050] Exemplarily, under the condition that other parameters are the same, such as under the condition that the code word enabling condition is the same, the DMRS type is the same, and the maxLength is the same, one DMRS port group can correspond to multiple DMRS port indexes. In this case, one DMRS port index can be used to indicate a precoding scheme of the network device, or multiple DMRS port indexes correspond to multiple precoding schemes one by one. In other words, one DMRS port index can be used to indicate an interference cancellation mode, or multiple DMRS port indexes correspond to multiple interference cancellation modes one by one.

[0051] In this way, through the interaction of the first information, the terminal device can not only obtain the precoding scheme of the network device, but also obtain the DMRS port number, thereby helping to reduce the signaling overhead.

[0052] In some embodiments, the determining the first information comprises: receiving capability information of the terminal device, the capability information being used to indicate the capability of the terminal device to cancel the interference between the multiple transmission layers; and determining the first information based on the capability information.

[0053] In other words, the capability information of the terminal device can be used to indicate the capability of the terminal device to cancel the interference between multiple sub-receivers.

[0054] Based on the foregoing introduction, it can be known that the network device can determine the precoding scheme based on the capability information of the terminal device. Further, the network device can determine the first information based on the precoding scheme. In other words, the network device can determine the first information based on the capability information of the terminal device.

[0055] The capability information of the terminal device is considered when determining the precoding scheme, which helps to avoid eliminating interference that the terminal device does not support to eliminate, and the resulting decline in reception performance.

[0056] In some embodiments, the interference between the multiple transmission layers includes third interference, and the determining the first information based on the capability information includes: in a case where the capability information indicates that the terminal device has the capability of eliminating the third interference, the first information is used to indicate that the network device eliminates interference other than the third interference from the interference between the multiple transmission layers.

[0057] Taking an example in which the transmission layers include a first transmission layer and a second transmission layer, the third interference mentioned here can be the first interference and / or the second interference mentioned in the foregoing.

[0058] That is, the network device can eliminate interference that the terminal device cannot eliminate. This is because the pre-elimination of interference by the network device reduces the transmission power of the useful signal, thereby causing the signal-to-noise ratio at the receiving end to decline. Therefore, the network device eliminates interference that the terminal device cannot eliminate, which helps to reduce the impact of interference elimination on the transmission power of the useful signal, thereby helping to improve the downlink reception performance.

[0059] In some embodiments, in a case where a first condition is met, the first information can be used to indicate whether the network device eliminates interference between multiple transmission layers, or in other words, the first information is used to indicate whether the network device eliminates interference between multiple receivers of the terminal device; and in a case where the first condition is not met, the first information can be used to indicate a codeword associated with the first channel state information.

[0060] Exemplarily, the first condition can be related to the number of transmission layers, or in other words, the first condition can be related to rank, or in other words, the first condition can be related to the number of antennas of multiple sub-receivers of the terminal device.

[0061] For example, the first condition can be that the number of transmission layers is greater than A, or the first condition can be that the number of transmission layers is greater than or equal to A.

[0062] In some embodiments, in a case where the number of transmission layers between the network device and the terminal device is greater than A, the first information is used to indicate whether the network device eliminates interference between the multiple transmission layers; and / or in a case where the number of transmission layers between the network device and the terminal device is less than or equal to A, the first information is used to indicate a codeword associated with the first channel state information; where A is a positive integer.

[0063] In some embodiments, the number of transmission layers corresponding to the first codeword is n, the number of transmission layers corresponding to the second codeword is m, and A is the maximum of m and n. Alternatively, A can be max(m, n).

[0064] Exemplarily, the terminal device supports independent reception of the first sub-receiver and supports independent reception of the second sub-receiver, and A can be the maximum of m and n.

[0065] In some embodiments, the first information is carried in radio resource control (RRC) signaling or downlink control information (DCI).

[0066] Exemplarily, the index of the precoding scheme (i.e., the first information) can be carried in RRC. In this way, after the precoding scheme is configured to the terminal device through RRC, the network device performs interference cancellation according to the precoding scheme.

[0067] Exemplarily, the first information is carried in DCI, and the precoding scheme can be dynamically adjusted according to channel changes, such as different precoding schemes can be used at different times, thereby helping to improve the flexibility of interference cancellation. For example, the DMRS port field (i.e., the first information) can be carried in DCI.

[0068] In a third aspect, a communication method is provided, which includes: receiving first information, the first information being used to indicate a codeword associated with first channel state information, the first channel state information being used to precode downlink information; and receiving the downlink information based on the first information.

[0069] Exemplarily, the communication method can be implemented by a terminal device, or by a component inside the terminal device, such as a processor, a circuit, a chip, or a chip system.

[0070] Exemplarily, the first information can be used to indicate a precoding scheme of a network device. In some embodiments, the precoding scheme can indicate which channel state information associated with a codeword is used by the network device for precoding, or which antenna of a sub-receiver corresponding to the channel state information is used by the network device for precoding.

[0071] The terminal device can include multiple sub-receivers, different sub-receivers corresponding to different codewords, different sub-receivers corresponding to different channels, and different channel state information of different channels (which can be referred to as different sub-receivers corresponding to different channel state information). Based on this, if the first channel state information is the channel state information corresponding to the first sub-receiver, the codeword associated with the first channel state information is the codeword corresponding to the first sub-receiver.

[0072] Generally, the network device can precode the downlink information according to the channel state information, so as to better adapt to the channel characteristics and improve the performance of the system, such as increasing the transmission rate, improving the bit error rate, or enhancing the reliability of the signal.

[0073] In some embodiments, in the case that the terminal device has multiple sub-receivers, the network device can precode based on the channel state information corresponding to one of the multiple sub-receivers (also referred to as independent precoding), or precode based on the channel state information corresponding to multiple sub-receivers (also referred to as joint precoding).

[0074] Taking the case that the terminal device includes two sub-receivers as an example, on the receiving side, the terminal device can receive the downlink signal through the first sub-receiver, or receive the downlink signal through the second sub-receiver, or jointly receive the downlink signal through the first sub-receiver and the second sub-receiver.

[0075] In the case that the network device precodes based on the channel state information corresponding to the first sub-receiver (i.e., the first channel state information is the channel state information corresponding to the first sub-receiver), if the terminal device receives the downlink signal by using the second sub-receiver, the downlink reception performance is poor. Similarly, in the case that the network device precodes based on the channel state information corresponding to the second sub-receiver, if the terminal device receives the downlink signal by using the first sub-receiver, the downlink reception performance is poor.

[0076] That is, in the case that the network device precodes based on the first channel state information, the terminal device receives the downlink signal by using the sub-receiver corresponding to the first channel information, and can obtain better downlink reception performance.

[0077] Based on this, in the embodiments of the present application, the network device can indicate the code word associated with the first channel state information (i.e., the first information) to the terminal device, which helps the terminal device to determine the code word used in the process of receiving the downlink information, or in other words, helps the terminal device to determine the sub-receiver for receiving the downlink information. In this way, the terminal device can receive the downlink signal by using the sub-receiver corresponding to the first channel state information, which helps to improve the downlink reception performance.

[0078] In some embodiments, the multiple transmission layers include a first transmission layer and a second transmission layer, the code word corresponding to the first transmission layer is a first code word, the code word corresponding to the second transmission layer is a second code word, and the first information is used to indicate one or more of the following: the code word associated with the first channel state information is the first code word; the code word associated with the first channel state information is the second code word; or the code word associated with the first channel state information includes the first code word and the second code word.

[0079] In other words, the first information can be used to indicate one or more of the following: the receiver associated with the first channel state information is the first receiver (i.e., the network device performs precoding based on the antenna group of the first receiver); the receiver associated with the first channel state information is the second receiver (i.e., the network device performs precoding based on the antenna group of the second receiver); or the receiver associated with the first channel state information includes the first receiver and the second receiver (i.e., the network device performs precoding based on all antenna groups of the first receiver and the second receiver). The first transmission layer corresponds to the first sub-receiver, and the second transmission layer corresponds to the second sub-receiver.

[0080] For example, the first information can include an identification of a code word associated with the first channel state information, or the first information can include an identification of a sub-receiver associated with the first channel state information, or the first information can include an identification of a transmission layer associated with the first channel state information.

[0081] Based on the first information, a code word or a sub-receiver used to receive the downlink information can be determined, so that the sub-receiver is used to receive the downlink information. If the first information indicates that the code word associated with the first channel state information is the first code word, the terminal device uses the sub-receiver corresponding to the first code word to receive the downlink information. If the first information indicates that the code word associated with the first channel state information is the second code word, the terminal device uses the sub-receiver corresponding to the second code word to receive the downlink information. If the first information indicates that the code word associated with the first channel state information includes the first code word and the second code word, the terminal device uses the sub-receiver corresponding to the first code word and the sub-receiver corresponding to the second code word to receive the downlink information, i.e., uses multiple sub-receivers for joint reception.

[0082] In some embodiments, the first information can include a precoding index, and different index values are used to indicate the precoding scheme adopted by the network device, such as the code word or the sub-receiver associated with the first channel state information. This scheme is simple to implement.

[0083] In some embodiments, the first information comprises a first transport block field and / or a second transport block field, if the first transport block field indicates that a first transport block is disabled and a first subfield of the first transport block field takes a first value, a code word associated with the first channel state information is the second code word; if the second transport block field indicates that a second transport block is disabled and a first subfield of the second transport block field takes the first value, the code word associated with the first channel state information is the first code word; if the first transport block field indicates that the first transport block is disabled and the first subfield of the first transport block field takes a second value, the code word associated with the first channel state information comprises the first code word and the second code word; if the second transport block field indicates that the second transport block is disabled and the first subfield of the second transport block field takes the second value, the code word associated with the first channel state information comprises the first code word and the second code word.

[0084] That is, the first information can multiplex a field in existing signaling, without defining a new signaling or field, thereby helping to reduce the degree of modification of the protocol by the scheme provided in the embodiments of the present application, and helping to reduce signaling overhead, so as to facilitate implementation.

[0085] The transport block field can comprise three subfields, a modulation and coding scheme (MCS) field, a redundancy version (RV) field, and a new data indicator (NDI) field. The first subfield can be any of the above fields.

[0086] In some embodiments, the first subfield is a new data indicator (NDI) field.

[0087] Exemplarily, the first value can be 1, and the second value can be 0.

[0088] In some embodiments, under the first condition, the first information can be used to indicate whether the network device cancels the interference between the multiple transport layers, or in other words, the first information is used to indicate whether the network device cancels the interference between the multiple receivers of the terminal device; under the condition that the first condition is not met, the first information can be used to indicate the code word associated with the first channel state information.

[0089] Exemplarily, the first condition can be related to the number of transport layers, or in other words, the first condition can be related to rank, or in other words, the first condition can be related to the number of antennas of the multiple sub-receivers of the terminal device.

[0090] For example, the first condition can be that the number of transmission layers is greater than A, or the first condition can be that the number of transmission layers is greater than or equal to A.

[0091] In some embodiments, in a case where the number of transmission layers between the network device and the terminal device is greater than A, the first information is used to indicate whether the network device performs cancellation on interference between the plurality of transmission layers; and / or in a case where the number of transmission layers between the network device and the terminal device is less than or equal to A, the first information is used to indicate a codeword associated with the first channel state information; wherein A is a positive integer.

[0092] In some embodiments, the number of transmission layers corresponding to the first codeword is n, the number of transmission layers corresponding to the second codeword is m, and the A is the maximum of m and n. Alternatively, the A can be max(m, n).

[0093] For example, the terminal device supports independent reception of the first sub-receiver and supports independent reception of the second sub-receiver, and the A can be the maximum of m and n.

[0094] In some embodiments, the first information is carried in radio resource control (RRC) signaling or downlink control information (DCI).

[0095] For example, the index (i.e., the first information) of the precoding scheme shown in Table 8 can be carried in RRC. In this way, after the precoding scheme is configured to the terminal device through RRC, the network device can perform precoding according to the precoding scheme.

[0096] For example, the first information is carried in DCI, and the precoding scheme can be dynamically adjusted according to channel changes, such as different precoding schemes can be used at different times, thereby helping to improve the flexibility of precoding and downlink reception. For example, the first transport block field and / or the second transport block field can be carried in DCI.

[0097] In a fourth aspect, a communication method is provided, which includes determining first information, the first information being used to indicate a codeword associated with first channel state information, wherein the first channel state information is used to perform precoding on downlink information; and sending the first information.

[0098] For example, the communication method can be implemented by a network device, or by a component inside the network device, such as a processor, a circuit, a chip, or a chip system.

[0099] For example, the terminal device includes two sub-receivers. On the receiving side, the terminal device can receive downlink signals through the first sub-receiver, can receive downlink signals through the second sub-receiver, and can jointly receive downlink signals through the first sub-receiver and the second sub-receiver.

[0100] In a case where the network device performs precoding based on the channel state information corresponding to the first sub-receiver (i.e., the first channel state information is the channel state information corresponding to the first sub-receiver), if the terminal device receives the downlink signal by using the second sub-receiver, the downlink reception performance is poor. Similarly, in a case where the network device performs precoding based on the channel state information corresponding to the second sub-receiver, if the terminal device receives the downlink signal by using the first sub-receiver, the downlink reception performance is poor.

[0101] That is, in a case where the network device performs precoding by using the first channel state information, the terminal device receives the downlink signal by using the sub-receiver corresponding to the first channel state information, and better downlink reception performance can be obtained.

[0102] Based on this, in the embodiments of the present application, the network device can indicate the code word associated with the first channel state information (i.e., the first information) to the terminal device, which helps the terminal device to determine the code word used in the process of receiving the downlink information, or in other words, helps the terminal device to determine the sub-receiver for receiving the downlink information. In this way, the terminal device can receive the downlink signal by using the sub-receiver corresponding to the first channel state information, which helps to improve the downlink reception performance.

[0103] In some embodiments, the plurality of transmission layers includes a first transmission layer and a second transmission layer, the code word corresponding to the first transmission layer is a first code word, the code word corresponding to the second transmission layer is a second code word, and the first information is used to indicate one or more of the following: the code word associated with the first channel state information is the first code word; the code word associated with the first channel state information is the second code word; or the code word associated with the first channel state information includes the first code word and the second code word.

[0104] In other words, the first information can be used to indicate one or more of the following: the receiver associated with the first channel state information is the first receiver (i.e., the network device performs precoding based on the antenna group of the first receiver); the receiver associated with the first channel state information is the second receiver (i.e., the network device performs precoding based on the antenna group of the second receiver); or the receiver associated with the first channel state information includes the first receiver and the second receiver (i.e., the network device performs precoding based on all antenna groups of the first receiver and the second receiver). The first transmission layer corresponds to the first sub-receiver, and the second transmission layer corresponds to the second sub-receiver.

[0105] Exemplarily, the first information can comprise an identification of a codeword associated with the first channel state information, or the first information can comprise an identification of a sub-receiver associated with the first channel state information, or the first information can comprise an identification of a transmission layer associated with the first channel state information.

[0106] In some embodiments, the first information can comprise a precoding index, different index values being used to indicate a precoding scheme adopted by the network device, such as a codeword or a sub-receiver associated with the first channel state information. This scheme is simple to implement.

[0107] In some embodiments, the first information comprises a first transport block field and / or a second transport block field, if the first transport block field indicates that a first transport block is disabled and a first sub-field of the first transport block field takes a first value, then a codeword associated with the first channel state information is the second codeword; if the second transport block field indicates that a second transport block is disabled and a first sub-field of the second transport block field takes the first value, then the codeword associated with the first channel state information is the first codeword; if the first transport block field indicates that the first transport block is disabled and the first sub-field in the first transport block field takes a second value, then the codeword associated with the first channel state information comprises the first codeword and the second codeword; if the second transport block field indicates that the second transport block is disabled and the first sub-field in the second transport block field takes the second value, then the codeword associated with the first channel state information comprises the first codeword and the second codeword.

[0108] That is, the first information can multiplex a field in existing signaling, without the need to define new signaling or fields, thereby helping to reduce the degree of modification of the protocol by the scheme provided in the embodiments of the present application, and helping to reduce signaling overhead, so as to facilitate implementation.

[0109] The transport block field can comprise three sub-fields, namely a modulation and coding scheme (MCS) field, an RV field and an NDI field. The first sub-field can be any of the above fields.

[0110] In some embodiments, the first sub-field is a new data indicator (NDI) field.

[0111] Exemplarily, the first value can be 1 and the second value can be 0.

[0112] In some embodiments, the method further comprises determining a precoding weight corresponding to a transmission layer based on the first information.

[0113] Or, the precoding weight corresponding to the sub-receiver is determined according to the precoding scheme of the network device. Exemplarily, the precoding weight corresponding to the antenna can be determined according to the precoding scheme of the network device. Through the adjustment of the precoding weight, the direction of the beam sent by the network device can be adjusted, thereby helping to improve the downlink receiving performance.

[0114] In some embodiments, in the case where the first condition is met, the first information can be used to indicate whether the network device cancels the interference between the multiple transmission layers, or in other words, the first information is used to indicate whether the network device cancels the interference between the multiple receivers of the terminal device; in the case where the first condition is not met, the first information can be used to indicate the codeword associated with the first channel state information.

[0115] Exemplarily, the first condition can be related to the number of transmission layers, or in other words, the first condition can be related to the rank, or in other words, the first condition can be related to the number of antennas of the multiple sub-receivers of the terminal device.

[0116] For example, the first condition can be that the number of transmission layers is greater than A, or the first condition can be that the number of transmission layers is greater than or equal to A.

[0117] In some embodiments, in the case where the number of transmission layers between the network device and the terminal device is greater than A, the first information is used to indicate whether the network device cancels the interference between the multiple transmission layers; and / or in the case where the number of transmission layers between the network device and the terminal device is less than or equal to A, the first information is used to indicate the codeword associated with the first channel state information; wherein A is a positive integer.

[0118] In some embodiments, the number of transmission layers corresponding to the first codeword is n, the number of transmission layers corresponding to the second codeword is m, and the A is the maximum value in m and n. Or, A can be max(m, n).

[0119] Exemplarily, the terminal device supports independent reception of the first sub-receiver and supports independent reception of the second sub-receiver, and A can be the maximum value in m and n.

[0120] In some embodiments, the first information is carried in radio resource control (RRC) signaling or downlink control information (DCI).

[0121] Exemplarily, the index of the precoding scheme (i.e., the first information) shown in Table 8 can be carried in RRC. In this way, after the precoding scheme is configured to the terminal device through RRC, the network device can perform precoding according to the precoding scheme.

[0122] Exemplarily, the first information is carried in the DCI, and the precoding scheme can be dynamically adjusted according to the channel variation, for example, different precoding schemes can be used at different time points, thereby helping to improve the flexibility of precoding and downlink reception. For example, the first transport block field and / or the second transport block field can carry the information in the DCI.

[0123] In a fifth aspect, a communication apparatus is provided, which comprises units for performing each step in the possible implementation manners of any one of the first to fourth aspects.

[0124] In a sixth aspect, a communication apparatus is provided, which comprises at least one processor and a memory storing program instructions, when the program instructions stored in the memory are executed by the processor, the method in the possible implementation manners of any one of the first to fourth aspects is performed.

[0125] In a seventh aspect, a communication apparatus is provided, which comprises at least one processor and interface circuit, the at least one processor is configured to perform the method in the possible implementation manners of any one of the first to fourth aspects.

[0126] In an eighth aspect, a computer program product is provided, which comprises a computer program, when the part or all of the computer program is executed by a processor, the method in the possible implementation manners of any one of the first to fourth aspects is performed.

[0127] In a ninth aspect, a computer readable storage medium is provided, which stores a computer program, when the part or all of the computer program is executed, the method in the possible implementation manners of any one of the first to fourth aspects is performed.

[0128] In a tenth aspect, a chip is provided, which comprises a processor configured to invoke and run part or all of a computer program from a memory, so that a communication device installed with the chip performs the method in the possible implementation manners of any one of the first to fourth aspects. BRIEF DESCRIPTION OF DRAWINGS

[0129] Fig. 1 is a schematic diagram of the architecture of a communication system to which the embodiments of the present application are applied;

[0130] Fig. 2 is an example diagram of time-frequency resource mapping of DMRS;

[0131] Fig. 3 is an example diagram of a dual-splicing terminal device provided by the embodiments of the present application;

[0132] Fig. 4 is a flow diagram of a communication method provided by the embodiments of the present application;

[0133] FIG. 5 is a schematic block diagram of a communication device according to an embodiment of the present application;

[0134] FIG. 6 is a schematic block diagram of another communication device according to an embodiment of the present application. DETAILED DESCRIPTION

[0135] The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings.

[0136] In the description of the embodiments of the present application, unless otherwise specified, " / " represents that the objects before and after the " / " are in an "or" relationship, for example, A / B can represent A or B; "and / or" in the embodiments of the present application is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B can represent: A exists alone, A and B exist together, and B exists alone, where A and B can be singular or plural. In addition, in the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more than two. "At least one of the following" or the like means any combination of the items, including any combination of single item or multiple items. For example, at least one of a, b, or c can represent: a, b, c, a-b, a-c, b-c, or a-b-c, where a, b, and c can be single or multiple. In addition, in order to clearly describe the technical solutions of the embodiments of the present application, in the embodiments of the present application, "first", "second", and the like are used to distinguish the same items or similar items with basically the same function and role. Those skilled in the art can understand that "first", "second", and the like do not limit the quantity and execution order, and "first", "second", and the like do not necessarily mean different.

[0137] In the method embodiments of the embodiments of the present application, the size of the serial number does not mean the execution order, and the execution order should be determined according to its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0138] It can be understood that in the embodiments of the present application, "in the case of", "if", "when", "if", and the like can be used instead. In addition, these descriptions all mean that corresponding processing will be made under certain objective conditions, and are not limited to time, and do not require judgment actions when implemented, nor mean that there are other limitations.

[0139] It can be understood that some optional features in the embodiments of the present application can be implemented independently in some scenarios, solve corresponding technical problems, and achieve corresponding effects without relying on other features, such as the scheme currently based on. In some scenarios, it can also be combined with other features according to requirements. Correspondingly, the apparatus given in the embodiments of the present application can also implement these features or functions, which will not be described here.

[0140] In the embodiments of the present application, the same or similar parts between different embodiments can be mutually referred to, unless otherwise specified. In the embodiments of the present application, the terms and / or descriptions of different embodiments, and the technical features in each implementation / implementation method / realization method of each embodiment have consistency and can be mutually referred to, unless otherwise specified and logically conflicted. The technical features in different embodiments, and the technical features in each implementation / implementation method / realization method of each embodiment can be combined to form new embodiments, implementations, implementation methods, or realization methods according to their inherent logical relationship. The implementation methods of the present application described below do not constitute a limitation on the protection scope of the present application.

[0141] The present application can be applied to various communication systems. For example: a fifth generation (5th generation, 5G) system or a new radio (New radio, NR), a satellite communication system, a long term evolution (long term evolution, LTE) system, and a future communication system. Exemplarily, the present application can also be applied to device to device (device to device, D2D) communication, vehicle-to-everything (vehicle-to-everything, V2X) communication, machine to machine (machine to machine, M2M) communication, machine type communication (machine type communication, MTC), and internet of things (internet of things, IoT) communication system or other communication systems.

[0142] The following introduces the scenarios to which the embodiments of the present application are applicable from different perspectives. For example, the present application is applicable to the scenario of a homogeneous network, and is also applicable to the scenario of a heterogeneous network. For another example, the embodiments of the present application do not limit the transmission points, for example, the present application can involve multi-point cooperative transmission between a macro base station and a macro base station, between a micro base station and a micro base station, and between a macro base station and a micro base station. For another example, the embodiments of the present application are applicable to a frequency division duplex (FDD) system and a time division duplexing (TDD) system. For another example, the embodiments of the present application are applicable to a low-frequency scenario, and are also applicable to a high-frequency scenario. For another example, the embodiments of the present application are applicable to a single transmission-reception point (single-TRP) or multi-transmission-reception point (multi-TRP) scenario, and any derivative scenario thereof.

[0143] For ease of understanding, the following describes the communication system to which the embodiments of the present application are applicable, taking the communication system 10 shown in FIG. 1 as an example.

[0144] FIG. 1 is a schematic diagram of an architecture of a communication system 10 to which the embodiments of the present application are applied. As shown in FIG. 1, the communication system includes a radio access network (RAN) 100, wherein the RAN 100 includes at least one RAN node (such as 110a and 110b in FIG. 1, collectively referred to as 110), and can also include at least one terminal (such as 120a-120j in FIG. 1, collectively referred to as 120). The RAN 100 can also include other RAN nodes, for example, a wireless relay device and / or a wireless backhaul device (not shown in FIG. 1). The terminals 120 are connected to the RAN nodes 110 in a wireless manner. Terminals and terminals, and RAN nodes and RAN nodes can be connected to each other in a wired or wireless manner. The communication system 10 can also include a core network 200. The RAN nodes 110 are connected to the core network 200 in a wireless or wired manner. The core network devices in the core network 200 and the RAN nodes 110 in the RAN 100 can be independent and different physical devices, or can be the same physical device integrated with the logical functions of the core network devices and the logical functions of the RAN nodes. The communication system 10 can also include the Internet 300.

[0145] The RAN 100 can be an evolved universal terrestrial radio access (E-UTRA) system, a new radio (NR) system, and future wireless access systems defined in the 3rd generation partnership project (3GPP). The RAN 100 can also be an open radio access network (O-RAN or ORAN), a cloud radio access network (CRAN), or a wireless fidelity (WiFi) system. The RAN 100 can also be a communication system that combines two or more of the above systems.

[0146] The RAN node 110 (may also be referred to as an access network device, a RAN entity, or an access node, etc.) is configured to help terminals to access the communication system in a wireless manner. In a possible scenario, the RAN node can be a base station, an evolved NodeB (eNodeB), an access point (AP), a transmission reception point (TRP), a next generation NodeB (gNB), a base station in a future mobile communication system, or an access node in a WiFi system, etc. The RAN node can be a macro base station (e.g., 110a in FIG. 1), a micro base station or an indoor station (e.g., 110b in FIG. 1), a relay node or a donor node, or a wireless controller in a CRAN scenario. Optionally, the RAN node can also be a server, a wearable device, a vehicle or a vehicle-mounted device, etc. For example, the access network device in a vehicle to everything (V2X) technology can be a road side unit (RSU).

[0147] In another possible scenario, a terminal is assisted by multiple RAN nodes to implement wireless access, and different RAN nodes respectively implement part of functions of a base station. For example, a RAN node can be a central unit (CU), a distributed unit (DU), or a radio unit (RU), etc. Here, the CU can complete functions of a radio resource control protocol and PDCP of the base station, and can also complete a function of a service data adaptation protocol (SDAP); the DU can complete functions of a radio link control layer and a medium access control (MAC) layer of the base station, and can also complete a function of part of a physical layer or all of the physical layer. For specific descriptions of the above protocol layers, refer to related technical specifications of the 3GPP. The RU can be used to implement functions of transceiving a radio frequency signal. The CU and the DU can be two independent RAN nodes, or can be integrated in a same RAN node, for example, integrated in a baseband unit (BBU). The RU can be included in a radio frequency device or a radio frequency unit, for example, included in a remote radio unit (RRU), an active antenna unit (AAU), or a remote radio head (RRH). The CU can be further divided into a CU-control plane (CP) and a CU-user plane (UP) two types of RAN nodes.

[0148] In different systems, a RAN node can have different names. For example, in an O-RAN system, a CU can be referred to as an open CU (O-CU), a DU can be referred to as an open DU (O-DU), and a RU can be referred to as an open RU (O-RU). Correspondingly, the CU-CP can also be referred to as an O-CU-CP, the CU-UP can also be referred to as an O-CU-UP, and the RU can also be referred to as an O-RU. For ease of description, in embodiments of the present application, the CU, the CU-CP, the CU-UP, the DU, and the RU are taken as examples for description.

[0149] All or part of the functions of the RAN node in the present application can also be implemented by software functions running on hardware, or by virtualized functions instantiated on a platform, such as a cloud platform. The RAN node can also be provided with a communication module, circuit or chip for performing corresponding communication functions, and program instructions for performing corresponding communication functions. The RAN node in the present application can also be a logical node, logical module or software capable of implementing all or part of the functions of the RAN node. The embodiments of the present application do not limit the specific technology and specific device form of the RAN node.

[0150] The terminal 120 is a device with wireless transceiving function, which can send signals to the base station or receive signals from the base station. The terminal can also be referred to as user equipment (UE), terminal device, access terminal, subscriber unit, subscriber station, mobile station (MS), remote station, remote terminal, mobile terminal (MT), user terminal, wireless communication device, user agent, user device, and terminal device, etc. The terminal 120 can be a mobile phone, tablet computer, computer with wireless transceiving function, wearable device, vehicle, unmanned aerial vehicle, helicopter, airplane, ship, robot, mechanical arm, smart home device, etc. The embodiments of the present application do not limit the device form of the terminal.

[0151] Exemplarily, the terminal 120 can be an internet of things (IoT) device (e.g., a sensor, an electricity meter, a water meter, etc.), a V2X device, a station (ST) in a wireless local area network (WLAN), a cellular phone, a cordless phone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA) device, a handheld device having wireless communication function, a computing device or other processing device connected to a wireless modem, an in-vehicle device, a wearable device (which can also be referred to as a smart wearable device), a tablet, or a computer with wireless transceiver function, a virtual reality (VR) terminal, a wireless terminal in industrial control, a wireless terminal in self driving, a wireless terminal in remote medical treatment, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, a vehicle terminal, a vehicle with vehicle-to-vehicle (V2V) communication capability, a smart connected vehicle, a drone with UAV to UAV (U2U) communication capability, etc.

[0152] The roles of the base stations and the terminals can be relative, for example, the network element 120i in FIG. 1 can be a helicopter or a drone, which can be configured as a mobile base station, for those terminals 120j accessing to the wireless access network 100 through 120i, the terminal 120i is a base station; but for the base station 110a, 120i is a terminal, that is, 110a and 120i communicate through a wireless air interface protocol. Of course, 110a and 120i can also communicate through a base station-to-base station interface protocol, at this time, 120i is also a base station relative to 110a. Therefore, the base stations and the terminals can be collectively referred to as communication apparatuses, 110a and 110b in FIG. 1 can be referred to as communication apparatuses with base station function, and 120a-120j in FIG. 1 can be referred to as communication apparatuses with terminal function.

[0153] The base station and the terminal can be fixed in position or mobile. The base station and the terminal can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; can be deployed on water surface; can also be deployed on an airplane, a balloon and a man-made satellite. Embodiments of the present application do not limit the application scenarios of the base station and the terminal.

[0154] The communication scenarios used by embodiments of the present application are introduced above, and the communication terms related by embodiments of the present application will be introduced below.

[0155] Demodulation reference signal

[0156] The DMRS is used to estimate the equivalent channel matrix experienced by a data channel, such as a physical downlink shared channel (PDSCH) or a control channel, such as a physical downlink control channel (PDCCH), so as to be used for detection and demodulation of data. Taking the data channel PDSCH as an example, the DMRS is usually subjected to the same precoding as the transmitted data signal, so as to ensure that the DMRS and the data experience the same equivalent channel. Assuming that the DMRS vector transmitted by the sending end is s, the data symbol vector transmitted is x, the DMRS and the data are subjected to the same precoding operation (multiplication by the same precoding matrix P), and the corresponding received signal vector of the receiving end can be represented as:

[0157] Data:

[0158] DMRS:

[0159] It can be seen that, for the data signal and the reference signal, the equivalent channels experienced are Based on the known DMRS vector s, the receiving end can obtain the estimation result of the equivalent channel by using a channel estimation algorithm, such as least square (LS) channel estimation, minimum mean square error (MMSE) channel estimation, etc. Based on the equivalent channel, multiple-input multiple-output (MIMO) equalization and subsequent demodulation of the data signal can be completed.

[0160] Since the DMRS is used to estimate the equivalent channel , the dimension of which is N R ×R, where N RR is the number of transmission streams (also referred to as transmission layers, spatial layers or rank). Generally, one DMRS port corresponds to one spatial layer. For MIMO transmission with R transmission streams, R DMRS ports are needed. To ensure the quality of channel estimation, different DMRS ports are usually orthogonal ports. DMRS symbols corresponding to different DMRS ports are orthogonal in the frequency domain, time-frequency domain or code domain.

[0161] Since DMRS occupies time-frequency resources, it is necessary to reduce the overhead of DMRS as much as possible. In order to reduce the interference between DMRS resources corresponding to multiple DMRS ports, the DMRS resources are often mapped to the preset time-frequency resources by frequency division multiplexing, time division multiplexing or code division multiplexing. Currently, 5G NR supports two types of DMRS resource mapping. For type 1 DMRS, a maximum of 8 orthogonal ports can be supported; for type 2 DMRS, a maximum of 12 orthogonal ports can be supported.

[0162] For one DMRS port, in order to perform channel estimation on different time-frequency resources and ensure the quality of channel estimation, multiple DMRS symbols need to be sent in multiple time-frequency resources. DMRS can occupy at least one OFDM symbol in the time domain, and the bandwidth occupied in the frequency domain is the same as the scheduling bandwidth of the scheduled data signal. Multiple DMRS symbols corresponding to one port correspond to one reference signal sequence, and one reference signal sequence includes multiple reference signal sequence elements. The DMRS reference signal sequence can be a gold sequence. Taking the DMRS reference signal sequence as a gold sequence as an example, the nth element in the reference signal sequence can be generated by the following formula:

[0163] wherein the pseudo-random sequence c(n) can be a gold sequence with a sequence length of 31. For an output sequence c(n) with a length of M PN , n = 0, 1,..., M PN -1, c(n) can be defined as: c(n) = (x1(n+N C )+x2(n+N C ))mod 2 x1(n+31) = (x1(n+3)+x1(n))mod 2 x2(n+31) = (x2(n+3)+x2(n+2)+x2(n+1)+x2(n))mod 2

[0164] wherein N C = 1600. The first m sequence x1(n) can be initialized as x1(0) = 1, x1(n) = 0, n = 1, 2,..., 30. The second m sequence x2(n) is initialized by the parameter c init . c init can be defined as Here, l represents the OFDM symbol index contained within a time slot. This represents a slot index within a system frame. It can be configured via higher-level signaling. It is related to the cell ID, and can usually be equal to the cell ID. This is an initialization parameter and can take the value 0 or 1. λ represents the code division multiplexing (CDM) group index corresponding to the DMRS port.

[0165] The DMRS reference signal sequence corresponding to a port is mapped to the corresponding time-frequency resource by multiplying it with the corresponding mask sequence according to a preset time-frequency resource mapping rule. In the current NR protocol, two types of DMRS configuration methods are defined, as described above: type 1 DMRS and type 2 DMRS.

[0166] For port p, the m-th reference sequence element r(m) in the corresponding reference signal sequence is mapped to the index (k, l) according to the following rule. p,μ On the resource element (RE). Where the index is (k, l) p,μ The RE corresponds to an OFDM symbol with index l in the time domain and a subcarrier with index k in the frequency domain. The mapping rule satisfies:

[0167] Where k′=0,1; n = 0, 1, ...; l′ = 0, 1; μ is the subcarrier spacing parameter. To map to index (k, l) p The DMRS modulation symbol corresponding to the RE upper port p of μ. The symbol index of the starting OFDM symbol or the symbol index of the reference OFDM symbol occupied by the DMRS modulation symbol. w is the power scaling factor. t (l′) represents the time-domain mask element corresponding to the OFDM symbol with index l′, w f (k′) is the frequency domain mask element corresponding to the subcarrier with index k′, m=2n+k′, and Δ is the subcarrier offset factor.

[0168] For configuration type 1 (type 1 DMRS) mapping rules, the DMRS port p corresponds to w f (k′), w t The values ​​of (l′) and Δ can be determined according to Table 1.

[0169] Table 1

[0170] For type 2 DMRS mapping rule, the value of w f (k ′ ), w t (l ′ ), and Δ can be determined according to Table 2.

[0171] Table 2

[0172] where λ is the index of the CDM group to which the port p belongs, and the DMRS ports in the same orthogonal multiplexing group occupy the same time-frequency resources.

[0173] According to formula (1), the time-frequency resource mapping manner of type 1 DMRS is shown in FIG. 2(a).

[0174] For single-symbol DMRS (corresponding to l' = 0), a maximum of 4 ports are supported, and the DMRS resource occupies one OFDM symbol. The 4 DMRS ports are divided into 2 code division multiplexing groups (CDM groups), wherein CDM group 0 contains port 0 and port 1; and CDM group 1 contains port 2 and port 3. The CDM group 0 and the CDM group 1 are frequency division multiplexed (mapped on different frequency domain resources). The DMRS ports contained in the CDM group are mapped on the same time-frequency resources. The reference signals corresponding to the DMRS ports contained in the CDM group are distinguished by orthogonal cover codes (OCCs), thereby ensuring the orthogonality of the DMRS ports in the CDM group, thereby suppressing the interference between the DMRSs transmitted on different antenna ports.

[0175] Specifically, the port 0 and the port 1 are located in the same RE, and are mapped in the frequency domain in the form of a comb, that is, the port 0 and the port 1 occupy adjacent frequency domain resources with an interval of one subcarrier. For one DMRS port, the adjacent 2 REs occupied correspond to an OCC code word sequence with a length of 2. For example, for the subcarrier 0 and the subcarrier 2, the port 0 and the port 1 adopt a set of OCC code word sequences with a length of 2 (+1+1 and +1-1). Similarly, the port 2 and the port 3 are located in the same resource element (RE), and are mapped in the frequency domain in the form of a comb on the REs not occupied by the port 0 and the port 1. For the subcarrier 1 and the subcarrier 3, the port 2 and the port 3 adopt a set of OCC code word sequences with a length of 2 (+1+1 and +1-1).

[0176] For dual-symbol DMRS, maximum 8 ports are supported. The 8 DMRS ports are divided into 2 code division multiplexing (CDM) groups, where CDM group 0 contains port 0, port 1, port 4 and port 5; CDM group 1 contains port 2, port 3, port 6 and port 7. CDM group 0 and CDM group 1 are frequency division multiplexed, and the reference signals corresponding to the DMRS ports contained in a CDM group are distinguished by OCC.

[0177] Specifically, port 0, port 1, port 4 and port 5 are located in the same resource element (RE), and are mapped in the frequency domain in a comb manner, i.e., port 0, port 1, port 4 and port 5 occupy adjacent frequency domain resources with one subcarrier in between. For a DMRS port, the adjacent 2 subcarriers and 2 OFDM symbols correspond to an OCC code word sequence with a length of 4. For example, for subcarrier 0 and subcarrier 2 corresponding to OFDM symbol 1 and OFDM symbol 2, port 0, port 1, port 4 and port 5 use a set of OCC codes with a length of 4 (+1+1+1+1 / +1+1-1-1 / +1-1+1-1 / +1-1-1+1). Similarly, port 2, port 3, port 6 and port 7 are located in the same resource element (RE), and are mapped in the frequency domain in a comb manner on the subcarriers not occupied by port 0, port 1, port 4 and port 5. For subcarrier 1 and subcarrier 3 corresponding to OFDM symbol 1 and OFDM symbol 2, port 2, port 3, port 6 and port 7 use a set of OCC codes with a length of 4 (+1+1+1+1 / +1+1-1-1 / +1-1+1-1 / +1-1-1+1).

[0178] According to formula (1), the time-frequency resource mapping manner of type 2 DMRS is shown in FIG. 2(b).

[0179] For single-symbol type 2 DMRS, maximum 6 ports are supported. The 6 DMRS ports are divided into 3 CDM groups, and the CDM groups are frequency division multiplexed. Orthogonality between the reference signals corresponding to the DMRS ports within a CDM group is guaranteed by OCC. CDM group 0 contains port 0 and port 1; CDM group 1 contains port 2 and port 3; and CDM group 2 contains port 4 and port 5. The CDM groups are frequency division multiplexed (mapped on different frequency domain resources). The reference signals corresponding to the DMRS ports within a CDM group are mapped on the same time-frequency resources. The reference signals corresponding to the DMRS ports within a CDM group are distinguished by OCC. For a DMRS port, the corresponding DMRS reference signals are mapped in the frequency domain within multiple resource sub-blocks containing 2 contiguous subcarriers, and the adjacent resource sub-blocks are spaced by 4 subcarriers in the frequency domain.

[0180] Specifically, port 0 and port 1 are located in the same RE and are mapped in a comb manner. Taking 1 RB as the frequency domain resource granularity, for example, port 0 and port 1 occupy subcarrier 0, subcarrier 1, subcarrier 6, and subcarrier 7. Port 2 and port 3 occupy subcarrier 2, subcarrier 3, subcarrier 8, and subcarrier 9. Port 4 and port 5 occupy subcarrier 4, subcarrier 5, subcarrier 10, and subcarrier 11. For 2 DMRS ports within a CDM group, OCC code word sequences of length 2 (+1+1 and +1-1) are used in adjacent 2 subcarriers.

[0181] For dual-symbol type 2 DMRS, maximum 12 ports are supported. The 12 DMRS ports are divided into 3 CDM groups, and the CDM groups are frequency division multiplexed. The reference signals corresponding to the DMRS ports in a CDM group are orthogonalized by OCC. CDM group 0 contains port 0, port 1, port 6 and port 7; CDM group 1 contains port 2, port 3, port 8 and port 9; CDM group 2 contains port 4, port 5, port 10 and port 11. The CDM groups are frequency division multiplexed (mapped on different frequency domain resources). The reference signals corresponding to the DMRS ports in a CDM group are mapped on the same time-frequency resources. The reference signals corresponding to the DMRS ports in a CDM group are distinguished by OCC. For a DMRS port, the corresponding DMRS reference signal is mapped in the frequency domain in multiple resource subblocks containing 2 consecutive subcarriers, and the adjacent resource subblocks are spaced by 4 subcarriers in the frequency domain.

[0182] Specifically, the ports in a CDM group are located in the same RE, and are mapped in the frequency domain in a comb manner. Taking a frequency domain resource granularity of 1 RB as an example, port 0, port 1, port 6 and port 7 occupy subcarriers 0, 1, 6 and 7 corresponding to OFDM symbol 1 and OFDM symbol 2. Port 2, port 3, port 8 and port 9 occupy subcarriers 2, 3, 8 and 9 corresponding to OFDM symbol 1 and OFDM symbol 2. Port 4, port 5, port 10 and port 11 occupy subcarriers 4, 5, 10 and 11 corresponding to OFDM symbol 1 and OFDM symbol 2. For the 4 DMRS ports in a CDM group, the OCC code word sequence (+1+1+1+1 / +1+1-1-1 / +1-1+1-1 / +1-1-1+1) of length 4 is mapped in the 2 adjacent subcarriers corresponding to 2 OFDM symbols.

[0183] As described above, the NR protocol defines the DMRS symbol and time-frequency resource mapping method corresponding to the DMRS port. In each data transmission process, the network device needs to inform the terminal device of the allocated DMRS port. The terminal device can perform pilot signal reception and corresponding channel estimation process at the corresponding resource location based on the allocated DMRS port, according to the protocol-defined DMRS symbol generation method and time-frequency resource mapping rule. The DMRS port notification method defined in the current NR protocol adopts the method of semi-statically configuring DMRS type by high-layer signaling and dynamically notifying the allocated DMRS port index by DCI.

[0184] Exemplarily, the RRC signaling can be used to configure the DMRS type and the number of occupied symbols, such as the DMRS type configured by the high-layer signaling DMRS-DownlinkConfig. The specific signaling content is as follows:

[0185] The dmrs-Type can be used to indicate whether type 1 DMRS or type 2 DMRS is used.

[0186] The maxLength can be used to indicate whether single-symbol DMRS or double-symbol DMRS is used. Specifically, if the maxLength is configured as len2, it can be further indicated by DCI whether 1-symbol DMRS or 2-symbol DMRS is used. If the maxLength field is not configured, 1-symbol DMRS is used.

[0187] Exemplarily, the DCI signaling contains the field Antenna port (antenna port) for indicating the allocated DMRS port index. The NR protocol defines different DMRS port tables for different values of dmrs-Type and maxLength configurations.

[0188] For example, Tables 3 and 4 respectively give the DMRS tables corresponding to dmrs-type=1, maxLength=2 and dmrs-type=2, maxLength=2. The field Antenna port in the DCI signaling indicates the index value in the DMRS port table corresponding to the value of the high-layer signaling configured dmrs-type and maxLength. Each index value corresponds to one or more DMRS port indexes.

[0189] Table 3 DMRS port table corresponding to dmrs-Type=1, maxLength=2

[0190] Table 4 DMRS port table corresponding to dmrs-Type=2, maxLength=2

[0191] Generally, multi-stream transmission can effectively improve spectrum efficiency. The number of transmission streams can also be referred to as the number of transmission layers. In some embodiments, an 8R receiver can be used to receive downlink data to meet the requirement that the peak transmission rate of the downlink reaches 1.6 Gbps. The 8R receiver can refer to a receiver device including 8 receiving antennas.

[0192] Compared with a 4R receiver, the 8R receiver can significantly improve the downlink throughput of a single user in a cell and can also increase the coverage of users at the edge of the cell. The 8R receiver is also one of the main ways to enable 256 quadrature amplitude modulation (QAM) and higher order modulation schemes within a practical operating signal-to-interference ratio range.

[0193] However, when performing high-stream transmission (such as the number of transmission streams being greater than 4), the conventional 8R receiver scheme has the characteristics of being difficult to implement and having high computational complexity. A feasible solution is that a terminal device performs signal reception and processing on transmission layers corresponding to different code words respectively. Since different code words can correspond to different receivers, the above solution can be replaced, for example, by splitting an 8R receiver into two 4R sub-receivers for signal reception and processing, as shown in FIG. 3. The two 4R sub-receivers can be referred to as “virtual UEs”, and a terminal device including the two 4R sub-receivers can be referred to as a double-spliced terminal.

[0194] Referring to FIG. 3, a terminal device includes two 4R receivers, i.e., sub-receiver 1 and sub-receiver 2. Sub-receiver 1 can be understood as virtual UE1, and sub-receiver 2 can be understood as virtual UE2. Each sub-receiver can implement 4-stream transmission with a network device at most.

[0195] When multi-stream transmission is used for downlink transmission, some factors can affect the reception performance of downlink signals. For example, for the terminal device described above having multiple sub-receivers, some factors can affect the reception performance of downlink signals.

[0196] For example, there can be certain interference between multiple transmission layers corresponding to different code words, thereby causing a decrease in system performance. In other words, there can be certain interference between multiple sub-receivers of a terminal device.

[0197] For example, when a single code word can support multi-stream transmission, if the terminal device receives the downlink signal by using an inappropriate code word, the reception performance of the downlink signal will be affected. Or, when a single sub-receiver of the terminal device can support multi-stream transmission, if the terminal device receives the downlink signal by using an inappropriate sub-receiver, the reception performance of the downlink signal will be affected. Here, the single sub-receiver of the terminal device can support multi-stream transmission, for example, can mean that the number of transmission streams of the multi-stream transmission is less than or equal to the number of antennas of the single sub-receiver of the terminal device.

[0198] In view of the above factors, how to improve the reception performance of the downlink signal, for example, how to improve the reception performance of the downlink signal for the terminal device with multiple sub-receivers, is a problem to be solved.

[0199] Embodiments of the present application provide a communication method to solve one or more of the above problems. In embodiments of the present application, the network device can indicate the precoding scheme it uses to the terminal device, for example, by using the first information. According to the first information, the terminal device can determine the reception strategy of the downlink information, thereby helping to improve the downlink reception performance.

[0200] In some embodiments, the precoding scheme can indicate the interference cancellation scheme of the network device, or in other words, whether the network device cancels the interference between multiple transmission layers (the multiple transmission layers correspond to different code words). In other words, the precoding scheme can be used to indicate whether the network device cancels the interference between multiple sub-receivers of the terminal device.

[0201] Since the cancellation of the interference between the multiple transmission layers by the network device is performed before the interference occurs, the cancellation of the interference by the network device can also be referred to as the pre-cancellation of the interference by the network device, and the interference cancellation scheme of the network device can also be referred to as the interference pre-cancellation scheme.

[0202] In some embodiments, the precoding scheme can indicate which channel state information associated with a code word is used by the network device for precoding, or in other words, which channel state information corresponding to the antennas of a sub-receiver is used by the network device for precoding.

[0203] In some embodiments, the precoding scheme can be replaced by a precoding level.

[0204] The communication method provided by embodiments of the present application will be described in detail below in combination with two embodiments in view of different meanings of the precoding scheme.

[0205] FIG. 4 is a flowchart of a communication method provided by embodiments of the present application. It should be understood that the method provided by embodiments of the present application can be applied to a terminal device with multiple sub-receivers.

[0206] The method shown in FIG. 4 can involve the interaction between the terminal device and the network device. The terminal device can be any of the terminal devices mentioned above, or a chip, chip system, or processor supporting the terminal device to implement the method. The network device can be any of the network devices mentioned above, or a chip, chip system, or processor supporting the network device to implement the method.

[0207] The method provided by the embodiments of the present application is described below from the perspective of the interaction between the terminal device and the network device.

[0208] The method shown in FIG. 4 can include step S410 and step S420.

[0209] S410, the terminal device receives first information. Correspondingly, the network device can send the first information to the terminal device.

[0210] The above-mentioned first information can be used to indicate whether the network device cancels the interference between the multiple transmission layers. The multiple transmission layers correspond to different code words.

[0211] In the case that the terminal device has multiple sub-receivers, different sub-receivers usually correspond to different code words, or different sub-receivers usually use different code words for signal transmission and reception. Therefore, the first information can be used to indicate whether the network device cancels the interference between the multiple sub-receivers.

[0212] The multiple transmission layers corresponding to different code words can be understood as the transmission layers corresponding to different sub-receivers. In the case that the sub-receiver includes multiple antennas, one sub-receiver can correspond to multiple transmission layers. In this case, the multiple transmission layers corresponding to different code words can be replaced by multiple transmission layer sets corresponding to different code words, where different transmission layer sets in the multiple transmission layer sets correspond to different code words. The transmission layers included in the transmission layer set mentioned here can correspond to the same sub-receiver.

[0213] In some embodiments, the interference between the multiple transmission layers can include multiple kinds of interference. Taking the case that the multiple transmission layers include a first transmission layer and a second transmission layer as an example, the interference between the multiple transmission layers can include the interference of the first transmission layer to the second transmission layer, and / or the interference of the second transmission layer to the first transmission layer.

[0214] Or, the interference between the multiple sub-receivers can include multiple kinds of interference. Taking the case that the sub-receivers include a first sub-receiver and a second sub-receiver as an example, the interference between the multiple sub-receivers can include the interference between the first sub-receiver to the second sub-receiver, and / or the interference of the second sub-receiver to the first sub-receiver.

[0215] In some embodiments, the first information can be used to indicate whether the network device cancels the multiple interferences between the multiple transmission layers. Alternatively, the first information can be used to indicate whether the network device cancels the multiple interferences between the multiple sub-receivers.

[0216] For example, the first information can be used to indicate that the network device cancels all the multiple interferences between the multiple transmission layers, or alternatively, the network device does not cancel the multiple interferences between the multiple transmission layers.

[0217] For example, the default precoding scheme, i.e. the default interference cancellation manner, can be predefined or preconfigured, which helps to reduce the indication overhead. The interference cancellation manner can be a manner in which the network device cancels the interferences between the multiple transmission layers.

[0218] For example, in the case that the interferences between the multiple transmission layers are large, or in the case that the downlink channel quality is poor, the default precoding scheme can indicate that the network device cancels all the multiple interferences between the multiple transmission layers.

[0219] For another example, in the case that the interferences between the multiple transmission layers are small, or in the case that the downlink channel quality is good, the default precoding scheme can indicate that the network device does not cancel the multiple interferences between the multiple transmission layers, which helps to reduce the overhead of cancelling the interferences.

[0220] For example, the first information can be used to indicate which of the multiple interferences between the multiple transmission layers are cancelled by the network device and which of the multiple interferences between the multiple transmission layers are not cancelled by the network device.

[0221] For example, taking the interference of the first transmission layer to the second transmission layer as the first interference, and the interference of the second transmission layer to the first transmission layer as the second interference, the first information can be used to indicate one or more of: the network device does not cancel the first interference and the second interference; the network device cancels the first interference; the network device cancels the second interference; or the network device cancels the first interference and the second interference.

[0222] Alternatively, the first information can be used to indicate one or more of: a precoding scheme used by the network device is used to cancel the first interference; the precoding scheme is used to cancel the second interference; the precoding scheme is used to cancel the first interference and the second interference; or the precoding scheme is not used to cancel the first interference and the second interference. This is because different precoding schemes, or alternatively different precoding matrices, can cancel different interferences.

[0223] The above four cases can be referred to as four different interference cancellation manners. Among them, the network device cancels the first interference and the second interference, which can also be referred to as the network device cancelling all the interferences between the multiple sub-receivers, or alternatively referred to as complete interference cancellation.

[0224] For example, the first information can indicate the precoding scheme of the network device through different indexes, as shown in Table 5.

[0225] Table 5

[0226] For example, the first information can be implemented through multiple bits.

[0227] For example, the first information can be implemented through 4 bits when the multiple transmission layers include two transmission layers, or the multiple sub-receivers include two sub-receivers. Each bit corresponds to an interference cancellation manner. Different values of each bit are used to indicate whether the interference cancellation manner corresponding to the bit is adopted.

[0228] For example, the first information can be implemented through 2 bits. Each value of the 2 bits corresponds to an interference cancellation manner, such as values 00, 01, 10, and 11 corresponding to an interference cancellation manner respectively. For example, the values of the 2 bits can be the indexes in Table 1, and different indexes are used to indicate different precoding schemes.

[0229] For example, in the case where there is a default precoding scheme (or referred to as a default interference cancellation manner), if the first information is not indicated, the default precoding scheme is adopted; if the first information is indicated, the default precoding scheme is not adopted. Further, different values of the first information are used to indicate different interference cancellation manners except the default interference manner.

[0230] For example, in the case where there is a default precoding scheme, the first information can include two parts of information, the first part of information is used to indicate whether the default precoding scheme is adopted, and the second part of information is used to indicate the interference cancellation manner adopted by the network device in the case where the default precoding scheme is not adopted. It should be understood that the second part of information is valid in the case where the first part of information indicates that the default precoding scheme is not adopted.

[0231] S420, the terminal device receives the downlink information based on the first information.

[0232] According to the foregoing introduction, it can be known that the network device can only cancel part of the interference between the multiple transmission layers, or the network device can not cancel the interference between the multiple transmission layers. In view of this, in some embodiments, the terminal device can cancel other interference not cancelled by the network device, thereby helping to avoid the reduction of downlink reception performance caused by the interference between the multiple transmission layers.

[0233] Exemplarily, if the first information indicates that the network device eliminates the first interference, the terminal device can eliminate the second interference when receiving the downlink information. If the first information indicates that the network device eliminates the second interference, the terminal device can eliminate the first interference when receiving the downlink information. If the first information indicates that the network device eliminates both the first interference and the second interference, the terminal device does not need to eliminate the first interference and the second interference when receiving the downlink information. If the first information indicates that the network device does not eliminate both the first interference and the second interference, the terminal device can eliminate both the first interference and the second interference when receiving the downlink information.

[0234] Suppose that the terminal device cannot obtain the precoding scheme of the network device, the terminal device cannot determine which interference between the multiple transmission layers needs to be eliminated. Then there will be two cases: one is that part of the interference between the transmission layers is not eliminated, which will affect the downlink reception performance; the other is that the terminal device repeatedly eliminates the interference between the transmission layers, which will increase unnecessary overhead.

[0235] Therefore, in the embodiment of the present application, through the interaction of the first information, the terminal device and the network device can reach a consensus on the precoding scheme of the network device, which provides support for determining the interference elimination scheme of the terminal device. For example, the terminal device can eliminate the interference between the multiple transmission layers which is not eliminated by the network device, thereby helping to avoid the influence of the interference on the downlink reception performance and helping to avoid unnecessary overhead on the terminal device side.

[0236] In some embodiments, the first information can multiplex a field in the existing signaling, without defining a new signaling or field, thereby helping to reduce the degree of change of the protocol provided by the scheme of the present application, and helping to reduce the signaling overhead, so as to facilitate implementation.

[0237] Exemplarily, the first information can include a DMRS port index, or in other words, the first information can multiplex a DMRS port index field. The DMRS port index can be used to indicate the precoding scheme of the network device. That is, the first information can be used to indicate whether the network device eliminates the interference between the multiple transmission layers, or in other words, the first information can be used to indicate whether the network device eliminates the interference between the multiple sub-receivers.

[0238] In the related art, one DMRS port group can correspond to one DMRS port index, wherein one DMRS port group can include one or more DMRS ports. For example, one DMRS port group can correspond to one DMRS port index in the case that other parameters are the same, such as the same codeword enabling case, the same DMRS type, and the same maxLength mentioned above.

[0239] In the embodiments of the present application, one DMRS port group can correspond to multiple DMRS port indexes, such as one DMRS port group corresponding to multiple DMRS port indexes in the case that other parameters are the same as mentioned above. In this case, one DMRS port index can be used to indicate one precoding scheme of the network device, or multiple DMRS port indexes correspond to multiple precoding schemes one by one. In other words, one DMRS port index can be used to indicate one interference cancellation manner, or multiple DMRS port indexes correspond to multiple interference cancellation manners one by one.

[0240] In some embodiments, the DMRS port table can be extended, such as the tables 3 and 4 mentioned above, to support the above method.

[0241] Referring back to Table 3, in the case that both codeword 0 and codeword 1 are enabled, taking index 1, the DMRS port group including DMRS ports 0, 1, 2, 3, 4, and 6 as an example, the extension method of the DMRS port table is introduced. Exemplarily, considering the four interference cancellation manners mentioned above (i.e. only considering the case of two sub-receivers), the DMRS port table can be extended by three rows, as shown in Table 6.

[0242] Table 6

[0243] It should be understood that the extended index values can use the reserved index values, i.e. 4-31, to avoid conflicts with existing indexes.

[0244] Referring to Table 6, the content corresponding to index 1 is the content in the DMRS port table in the related art, and the content corresponding to index 4, index 5, and index 6 is the extended content in the embodiments of the present application.

[0245] The above index 1, index 4, index 5, and index 6 correspond to one interference cancellation manner respectively. As an example, when the DMRS port group in Table 6 is used, index 1 can be used to indicate that the network device does not cancel the first interference and the second interference; index 4 can be used to indicate that the network device cancels the first interference; index 5 can be used to indicate that the network device cancels the second interference; and index 6 can be used to indicate that the network device cancels both the first interference and the second interference.

[0246] It should be noted that the correspondence between the index value and the interference cancellation mode is only given as an example, and the present application does not limit the same.

[0247] As mentioned above, in general, the number of DMRS ports corresponds to the number of transmission layers or spatial layers. When the terminal device uses two or more sub-receivers to support multi-stream transmission, the interference between the sub-receivers needs to be cancelled. Based on this, in some embodiments, the number of transmission streams supported by the sub-receivers of the terminal device can be used to determine which rows in the DMRS port table are extended, thereby helping to reduce the implementation complexity.

[0248] Taking the terminal device in FIG. 3 as an example, the terminal device includes two sub-receivers, and each sub-receiver can support a maximum of 4-stream transmission. That is, when the transmission is greater than 4-stream, the terminal device needs to use two sub-receivers to receive simultaneously. At this time, there is interference between multiple sub-receivers. For this terminal device, the rows in which the DMRS port groups including more than 4 DMRS ports in the DMRS port table can be extended.

[0249] As an example, referring back to Table 3, when both codeword 0 and codeword 1 are enabled, the number of DMRS ports included in the DMRS port groups corresponding to index 1, index 2, and index 3 are all greater than 4. Therefore, the rows in which the DMRS port groups corresponding to index 1, index 2, and index 3 are extended.

[0250] As another example, referring back to Table 4, when both codeword 0 and codeword 1 are enabled, the number of DMRS ports included in the DMRS port groups corresponding to index 1, index 2, index 3, index 4, and index 5 are all greater than 4. Therefore, the rows in which the DMRS port groups corresponding to index 1, index 2, index 3, index 4, and index 5 are extended, as shown in Table 7.

[0251] Table 7

[0252] Referring to Table 7, when the adopted DMRS port group includes DMRS ports 0-5, the four interference cancellation modes mentioned above can be indicated by index 1, index 6, index 11, and index 16, respectively; when the adopted DMRS port group includes DMRS ports 0, 1, 2, 3, 6, the four interference cancellation modes mentioned above can be indicated by index 2, index 7, index 12, and index 17, respectively; when the adopted DMRS port group includes DMRS ports 0, 1, 2, 3, 6, 8, the four interference cancellation modes mentioned above can be indicated by index 3, index 8, index 13, and index 18, respectively; when the adopted DMRS port group includes DMRS ports 0, 1, 2, 3, 6, 7, 8, the four interference cancellation modes mentioned above can be indicated by index 4, index 9, index 14, and index 19, respectively; and when the adopted DMRS port group includes DMRS ports 0, 1, 2, 3, 6, 7, 8, 9, the four interference cancellation modes mentioned above can be indicated by index 5, index 10, index 15, and index 20, respectively.

[0253] It should be understood that the extended index value can adopt the reserved index value, i.e., 6-63, to avoid conflict with the existing index.

[0254] It should be noted that the correspondence between the index value and the interference cancellation mode is only given by way of example, and the present application does not limit this.

[0255] In this way, through the interaction of the first information, the terminal device can not only obtain the precoding scheme of the network device, but also obtain the DMRS port number, thereby helping to reduce the signaling overhead.

[0256] As mentioned above, when the terminal device adopts two or more sub-receivers to support multi-stream transmission, the interference between the multiple sub-receivers needs to be cancelled. However, when the number of transmission streams is less than or equal to the number of transmission streams supported by one sub-receiver of the terminal device, the terminal device can also use multiple sub-receivers to receive the downlink signal to improve reliability. Considering this situation, the terminal device can extend all the rows in the DMRS port table, or the terminal device can extend part of the rows in the DMRS port table according to actual needs. The extension method of the DMRS port table is similar to the method introduced above, and will not be described here for brevity.

[0257] In some embodiments, the network device can determine the precoding scheme based on the capability of the terminal device, or in other words, the network device can determine the interference cancellation mode based on the capability of the terminal device.

[0258] Exemplarily, the terminal device can send capability information of the terminal device to the network device. Correspondingly, the network device can receive the capability information of the terminal device sent by the terminal device. The capability information can be used to indicate the capability of the terminal device to eliminate interference between multiple transmission layers, or in other words, the capability information can be used to indicate the capability of the terminal device to eliminate interference between multiple sub-receivers.

[0259] Still as mentioned above, taking that the multiple transmission layers include a first transmission layer and a second transmission layer as an example, the capability information can indicate that the terminal device has one or more of the following capabilities: eliminating the first interference; eliminating the second interference; eliminating the first interference and the second interference; or the terminal device does not have the capability of eliminating the first interference and the second interference.

[0260] Alternatively, the capability information can be used to indicate whether the terminal device has the capability of eliminating all interference between multiple sub-receivers. In the case that the terminal device does not have the capability of eliminating all interference between multiple sub-receivers, the capability information (or other information) can be used to indicate that the terminal device can eliminate those interference or cannot eliminate which interference.

[0261] Exemplarily, the network device can eliminate the interference that the terminal device cannot eliminate. This is because the pre-elimination of interference by the network device will reduce the transmission power of the useful signal, thereby causing the reception signal-to-noise ratio to drop. Therefore, the network device eliminates the interference that the terminal device cannot eliminate, which helps to reduce the impact of interference elimination on the transmission power of the useful signal, thereby helping to improve the downlink reception performance.

[0262] Alternatively, the interference between multiple transmission layers includes a third interference, and in the case that the above capability information indicates that the terminal device has the capability of eliminating the third interference, the network device can eliminate other interference in addition to the third interference between multiple transmission layers.

[0263] Taking that the transmission layers include a first transmission layer and a second transmission layer as an example, the third interference mentioned here can be the first interference and / or the second interference mentioned above. That is, if the capability information indicates that the terminal device has the capability of eliminating the first interference, the network device eliminates the second interference; if the capability information indicates that the terminal device has the capability of eliminating the second interference, the network device eliminates the first interference; if the capability information indicates that the terminal device has the capability of eliminating the first interference and the second interference, the network device does not eliminate the first interference and the second interference; and if the capability information indicates that the terminal device does not have the capability of eliminating the first interference and the second interference, the network device can eliminate the first interference and the second interference.

[0264] Based on the foregoing introduction, the network device can determine the precoding scheme based on the capability information of the terminal device. Further, the network device can determine the first information based on the precoding scheme. In other words, the network device can determine the first information based on the capability information of the terminal device. For example, in the case where the capability information indicates that the terminal device has the capability of canceling the third interference, the first information is used to indicate that the network device cancels other interference in addition to the third interference among the interference between the multiple transmission layers.

[0265] In some embodiments, the first information can be carried in RRC signaling or DCI.

[0266] For example, the index (i.e., the first information) of the precoding scheme shown in Table 5 can be carried in RRC. In this way, after the precoding scheme is configured to the terminal device through RRC, the network device performs interference cancellation according to the precoding scheme.

[0267] For example, the first information is carried in DCI, and the precoding scheme can be dynamically adjusted according to channel changes, such as different precoding schemes can be used at different times, thereby helping to improve the flexibility of interference cancellation. For example, the index (i.e., the first information) in Table 6 and Table 7 can be carried in DCI.

[0268] The following describes another communication method provided by an embodiment of the present application.

[0269] In this embodiment, the first information can be used to indicate a codeword associated with the first channel state information. The first channel state information can be used to precode the downlink information.

[0270] The terminal device can include multiple sub-receivers, different sub-receivers correspond to different codewords, different sub-receivers correspond to different channels, and the channel state information of different channels is different (which can be referred to as different sub-receivers correspond to different channel state information). Based on this, if the first channel state information is the channel state information corresponding to the first sub-receiver, the codeword associated with the first channel state information is the codeword corresponding to the first sub-receiver.

[0271] Generally, the network device can precode the downlink information according to the channel state information, so as to better adapt to the channel characteristics and improve the performance of the system, such as increasing the transmission rate, improving the bit error rate, or enhancing the reliability of the signal.

[0272] In some embodiments, in the case where the terminal device has multiple sub-receivers, the network device can precode based on the channel state information corresponding to one receiver of the multiple sub-receivers (which can also be referred to as independent precoding), or precode based on the channel state information corresponding to the multiple sub-receivers (which can also be referred to as joint precoding).

[0273] Taking an example of the terminal device including two sub-receivers, at the receiving side, the terminal device can receive the downlink signal through the first sub-receiver, can receive the downlink signal through the second sub-receiver, and can jointly receive the downlink signal through the first sub-receiver and the second sub-receiver.

[0274] In a case where the network device performs precoding based on the channel state information corresponding to the first sub-receiver (that is, the first channel state information is the channel state information corresponding to the first sub-receiver), if the terminal device receives the downlink signal by using the second sub-receiver, the downlink reception performance is poor. Similarly, in a case where the network device performs precoding based on the channel state information corresponding to the second sub-receiver, if the terminal device receives the downlink signal by using the first sub-receiver, the downlink reception performance is poor.

[0275] That is, in a case where the network device performs precoding by using the first channel state information, the terminal device receives the downlink signal by using the sub-receiver corresponding to the first channel information, and better downlink reception performance can be obtained.

[0276] Based on this, in the embodiments of the present application, the network device can indicate the code word associated with the first channel state information (that is, the first information) to the terminal device, which helps the terminal device to determine the code word used in the process of receiving the downlink information, or in other words, helps the terminal device to determine the sub-receiver for receiving the downlink information. In this way, the terminal device can receive the downlink signal by using the sub-receiver corresponding to the first channel state information, which helps to improve the downlink reception performance.

[0277] Still taking an example of the multiple transmission layers including a first transmission layer and a second transmission layer, the code word corresponding to the first transmission layer is a first code word, and the code word corresponding to the second transmission layer is a second code word.

[0278] In some embodiments, the first information can be used to indicate one or more of the following: the code word associated with the first channel state information is the first code word (that is, independent precoding); the code word associated with the first channel state information is the second code word (that is, independent precoding); or the code word associated with the first channel state information includes the first code word and the second code word (that is, joint precoding).

[0279] In other words, the first information can be used to indicate one or more of the following: the receiver associated with the first channel state information is the first receiver (i.e., the network device performs precoding based on the antenna group of the first receiver); the receiver associated with the first channel state information is the second receiver (i.e., the network device performs precoding based on the antenna group of the second receiver); or the receiver associated with the first channel state information includes the first receiver and the second receiver (i.e., the network device performs precoding based on all antenna groups of the first receiver and the second receiver). The first transmission layer corresponds to the first sub-receiver, and the second transmission layer corresponds to the second sub-receiver.

[0280] For example, the first information can include an identification of a codeword associated with the first channel state information, or the first information can include an identification of a sub-receiver associated with the first channel state information, or the first information can include an identification of a transmission layer associated with the first channel state information.

[0281] In some embodiments, the first information can include a precoding index, and different index values can be used to indicate different precoding schemes adopted by the network device, such as a codeword or a sub-receiver associated with the first channel state information, as shown in Table 8.

[0282] Table 8

[0283] For example, the first information can be implemented by a plurality of bits (or a bit sequence). For example, each bit of the plurality of bits corresponds to a precoding scheme. For another example, different values of the bit sequence indicate different precoding schemes, such as the values of the bit sequence can include the index values in Table 8.

[0284] In some embodiments, the first information can be used to indicate independent precoding or joint precoding. In the case where the first information indicates that the network device adopts independent precoding, the first information can also be used to indicate a codeword associated with the first channel information. In other words, the first information can include two parts of content, the first part can be used to indicate that the precoding scheme is independent precoding or joint precoding, and the second part can be used to indicate a codeword associated with the first channel information. It should be understood that the second part of the first information can be valid in the case where the first part indicates that the precoding scheme is independent precoding.

[0285] In some embodiments, a default precoding scheme can be predefined or preconfigured, such as the default precoding scheme is joint precoding or independent precoding. In the case where the network device adopts the default precoding scheme, the first information can not be indicated to save the indication overhead. In the case where the network device adopts a non-default precoding scheme, the first information can be used to indicate the precoding scheme adopted by the network device.

[0286] Since joint precoding helps to improve the reliability of downlink reception, using joint precoding as the default precoding scheme helps to improve the performance of downlink reception.

[0287] The method of receiving downlink information based on the first information is described below.

[0288] Based on the first information, the code word or sub-receiver used to receive the downlink information can be determined, so that the sub-receiver is used to receive the downlink information.

[0289] If the first information indicates that the code word associated with the first channel state information is the first code word, the terminal device uses the sub-receiver corresponding to the first code word to receive the downlink information.

[0290] If the first information indicates that the code word associated with the first channel state information is the second code word, the terminal device uses the sub-receiver corresponding to the second code word to receive the downlink information.

[0291] If the first information indicates that the code word associated with the first channel state information includes the first code word and the second code word, the terminal device uses the sub-receiver corresponding to the first code word and the sub-receiver corresponding to the second code word to receive the downlink information, that is, uses multiple sub-receivers for joint reception.

[0292] In some embodiments, in the case where the terminal device uses multiple sub-receivers for joint reception, the first information (or other information) can be used to indicate the aforementioned interference cancellation method.

[0293] In some embodiments, the first information can reuse the fields in the existing signaling, without the need to define new signaling or fields, thereby helping to reduce the degree of change of the protocol provided by the embodiments of the present application, and helping to reduce signaling overhead, so as to facilitate implementation.

[0294] Exemplarily, the first information can include a transport block field, or in other words, the first information can reuse the transport block field. The transport block field mentioned here can include a first transport block sub-block and / or a second transport block field.

[0295] The transport block field can include three sub-fields, namely an MCS field, an RV field, and an NDI field. The first sub-field can be any of the above fields.

[0296] There are various methods to indicate that the transport block is disabled (or referred to as transport block disabled). Exemplarily, the size of the transport block can be set to 0 to indicate that the transport block is disabled. Exemplarily, the MCS field in the transport block field can be set to a reserved value to indicate that the transport block is disabled. Exemplarily, the MCS field and the RV field in the transport block field can be combined to indicate that the transport block is disabled.

[0297] There are multiple methods for indicating the precoding scheme through the combination of the transmission block disabling and the first subfield. An example is given below, in which the first subfield is the NDI field.

[0298] For example, if the first transmission block field indicates that the first transmission block is disabled, and the first subfield of the first transmission block field takes the first value, the code word associated with the first channel state information is the second code word; if the second transmission block field indicates that the second transmission block is disabled, and the first subfield of the second transmission block field takes the first value, the code word associated with the first channel state information is the first code word.

[0299] For another example, if the first transmission block field indicates that the first transmission block is disabled, and the first subfield in the first transmission block field takes the second value, the code word associated with the first channel state information includes the first code word and the second code word; if the second transmission block field indicates that the second transmission block is disabled, and the first subfield in the second transmission block field takes the second value, the code word associated with the first channel state information includes the first code word and the second code word.

[0300] It should be understood that the first value can be 0 and the second value can be 1, or the first value can be 1 and the second value can be 0, which is not limited in the present application.

[0301] In this way, through the interaction of the first information, the terminal device can not only obtain the precoding scheme of the network device, but also obtain the indication information related to the transmission block, thereby helping to reduce the signaling overhead.

[0302] Before sending the first information, the network device can determine the precoding scheme, such as determining the precoding scheme based on the capability of the terminal device. For example, based on the capability of the terminal device, it can be determined which code word associated channel information is used for precoding.

[0303] In the case where the terminal device supports joint reception by multiple sub-receivers, such as supporting multiple sub-receivers to receive part or all of the same signal and supporting joint processing of the signal at the receiving end, the network device can use joint precoding or independent precoding. Alternatively, in this case, the network device can use joint precoding, which helps to improve the reliability of downlink reception and thus improve the performance of downlink reception.

[0304] In the case where the terminal device does not support joint reception, the network device can use the channel state information corresponding to the first code word for precoding, or use the channel state information corresponding to the second code word for precoding. For example, the network device can determine which code word corresponding channel state information is used for precoding according to the quality of the channel corresponding to the different code words.

[0305] In the case that the terminal device does not support joint reception, if the terminal device only supports independent reception by the receiver corresponding to the first codeword, the network device can perform precoding by using the channel state information associated with the first codeword; if the terminal device only supports independent reception by the receiver corresponding to the second codeword, the network device can perform precoding by using the channel state information associated with the second codeword.

[0306] In some embodiments, the precoding weight corresponding to the transmission layer, or the precoding weight corresponding to the sub-receiver, can be determined according to the precoding scheme of the network device (i.e., the first information). For example, the precoding weight corresponding to the antenna can be determined according to the precoding scheme of the network device. By adjusting the precoding weight, the direction of the beam transmitted by the network device can be adjusted, thereby helping to improve the downlink reception performance.

[0307] For example, if the first channel information is associated with the first codeword, the network device can adjust the precoding weight so that the main direction of the downlink beam (or the main beam of the downlink signal) is towards the first sub-receiver. If the first channel information is associated with the second codeword, the network device can adjust the precoding weight so that the main direction of the downlink beam (or the main beam of the downlink signal) is towards the second sub-receiver.

[0308] In the embodiments of the present application, the first information can be carried in RRC signaling or DCI.

[0309] For example, the index of the precoding scheme (i.e., the first information) shown in Table 8 can be carried in RRC. In this way, after the precoding scheme is configured to the terminal device by RRC, the network device can perform precoding according to the precoding scheme.

[0310] For example, the first information is carried in DCI, and the precoding scheme can be dynamically adjusted according to the channel change, for example, different precoding schemes can be used at different times, thereby helping to improve the flexibility of precoding and downlink reception. For example, the first transport block field and / or the second transport block field can be carried in DCI.

[0311] In some embodiments, the first information can be used to indicate whether the network device eliminates the interference between the multiple transmission layers, and the first information can be used to indicate the codeword associated with the first channel state information. For example, in the case that the network device performs joint precoding, the first information can be used to indicate whether the network device eliminates the interference between the multiple transmission layers, and the first information can be used to indicate the codeword associated with the first channel state information.

[0312] In some embodiments, the first information can be used to indicate whether the network device cancels the interference between the multiple transmission layers, or the interference between the multiple receivers of the terminal device, when the first condition is met; and the first information can be used to indicate the codeword associated with the first channel state information when the first condition is not met.

[0313] For example, the first condition can be related to the number of transmission layers, or the rank, or the number of antennas of the multiple sub-receivers of the terminal device.

[0314] For example, the first condition can be that the number of transmission layers is greater than A, or the first condition can be that the number of transmission layers is greater than or equal to A. That is, when the number of transmission layers between the network device and the terminal device is greater than A, the first information can be used to indicate whether the network device cancels the interference between the multiple transmission layers; when the number of transmission layers between the network device and the terminal device is less than or equal to A, the first information can be used to indicate the codeword associated with the first channel state information. Wherein A is a positive integer.

[0315] The number of transmission layers corresponding to the first codeword is n, and the number of transmission layers corresponding to the second codeword is m. Or, the number of antennas of the first sub-receiver is n, and the number of antennas of the second sub-receiver is m.

[0316] For example, A can be m or n. For example, the terminal device supports independent reception of the first sub-receiver, but does not support independent reception of the second sub-receiver, and A can be n. For example, the terminal device supports independent reception of the second sub-receiver, but does not support independent reception of the first sub-receiver, and A can be m.

[0317] For another example, A can be the maximum of m and n, or max(m, n). For example, the terminal device supports independent reception of the first sub-receiver and supports independent reception of the second sub-receiver, and A can be the maximum of m and n. For example, the terminal device includes two sub-receivers (2R+4R), that is, m is 2 and n is 4, and A can be 4.

[0318] It should be noted that the network device mentioned in the embodiments of the present application cancels the first interference and / or the second interference, which can mean that the network device has taken measures to cancel the first interference and / or the second interference, such as using a precoding matrix to cancel the first interference and / or the second interference. It should be understood that the network device cancels the first interference, which does not mean that the downlink signal does not absolutely include the first interference. In some cases, the downlink signal can still include part of the first interference.

[0319] The method embodiments provided in the present application are described above, and the device embodiments provided in the present application will be described below. It should be understood that the description of the device embodiments corresponds to the description of the method embodiments, and therefore, the content not described in detail can be referred to the method embodiments described above, which will not be repeated here for brevity.

[0320] FIG. 5 is a schematic block diagram of a communication device provided in an embodiment of the present application. As shown in FIG. 5, the communication device 500 can include a transceiver unit 510 and / or a processing unit 520. The transceiver unit 510 can implement corresponding communication functions, and the processing unit 520 is configured to perform data processing. The transceiver unit 510 can also be referred to as a communication interface or a communication unit. Optionally, the device 500 can further include a storage unit, which can be configured to store instructions and / or data, and the processing unit 520 can read the instructions and / or data in the storage unit to enable the device to implement the foregoing method embodiments.

[0321] In a possible design, the device 500 can be a terminal device in the method embodiments described above, or can be a chip, processor or chip system for implementing the functions of the terminal device. The device 500 can be configured to perform the steps or procedures performed by the terminal device in any of the method embodiments described above.

[0322] Specifically, the transceiver unit 510 can be configured to receive first information, the first information being used to indicate whether a network device cancels interference between a plurality of transmission layers, the plurality of transmission layers corresponding to different codewords, or the first information being used to indicate a codeword associated with first channel state information, the first channel state information being used to precode downlink information. The transceiver unit 510 can be configured to receive the downlink information based on the first information.

[0323] In some embodiments, the plurality of transmission layers includes a first transmission layer and a second transmission layer, the first transmission layer has a first interference to the second transmission layer, the second transmission layer has a second interference to the first transmission layer, and the first information is used to indicate one or more of the following: the network device does not cancel the first interference and the second interference; the network device cancels the first interference; the network device cancels the second interference; or the network device cancels both the first interference and the second interference.

[0324] In some embodiments, the first information includes a demodulation reference signal (DMRS) port index, and the DMRS port index is used to indicate whether the network device cancels the interference between the plurality of transmission layers.

[0325] In some embodiments, one DMRS port group includes a plurality of DMRS ports, one DMRS port group corresponds to a plurality of DMRS port indexes, and the plurality of DMRS port indexes correspond to a plurality of interference cancellation manners one by one, the interference cancellation manner being a manner in which the network device cancels interference between the plurality of transmission layers.

[0326] In some embodiments, before the first information is received, the transceiver 510 can be configured to: send capability information of the terminal device, the capability information being used to indicate a capability of the terminal device to cancel interference between the plurality of transmission layers.

[0327] In some embodiments, the plurality of transmission layers includes a first transmission layer and a second transmission layer, the first transmission layer corresponds to a first codeword, and the second transmission layer corresponds to a second codeword, and the first information is used to indicate one or more of the following: the codeword associated with the first channel state information is the first codeword; the codeword associated with the first channel state information is the second codeword; or the codeword associated with the first channel state information includes the first codeword and the second codeword.

[0328] In some embodiments, the first information includes a first transport block field and / or a second transport block field, if the first transport block field indicates that a first transport block is disabled and a first subfield of the first transport block field takes a first value, the codeword associated with the first channel state information is the second codeword; if the second transport block field indicates that a second transport block is disabled and a first subfield of the second transport block field takes a first value, the codeword associated with the first channel state information is the first codeword; if the first transport block field indicates that the first transport block is disabled and the first subfield in the first transport block field takes a second value, the codeword associated with the first channel state information includes the first codeword and the second codeword; and if the second transport block field indicates that the second transport block is disabled and the first subfield in the second transport block field takes a second value, the codeword associated with the first channel state information includes the first codeword and the second codeword.

[0329] In some embodiments, the first subfield is a new data indicator (NDI) field.

[0330] In some embodiments, when the number of transmission layers between the network device and the terminal device is greater than A, the first information is used to indicate whether the network device cancels interference between the plurality of transmission layers; and / or when the number of transmission layers between the network device and the terminal device is less than or equal to A, the first information is used to indicate the codeword associated with the first channel state information; wherein A is a positive integer.

[0331] In some embodiments, the number of transmission layers corresponding to the first codeword is n, the number of transmission layers corresponding to the second codeword is m, and the A is the maximum of m and n.

[0332] In some embodiments, the first information is carried in radio resource control (RRC) signaling or downlink control information (DCI).

[0333] In one possible design, the apparatus 500 can be a network device in the above method embodiments, or can be a chip, processor or chip system that implements the network device functions. The apparatus 500 can be configured to perform the steps or procedures executed by the network device in any of the above method embodiments.

[0334] In particular, the processing unit 520 can be configured to determine first information, the first information being used to indicate whether the network device cancels interference between multiple transmission layers of a terminal device or the first information being used to indicate a codeword associated with first channel state information, wherein the first channel state information is used to precode downlink information. The transceiver unit 510 can be configured to transmit the first information.

[0335] In some embodiments, the multiple transmission layers include a first transmission layer and a second transmission layer, the first transmission layer has a first interference to the second transmission layer, the second transmission layer has a second interference to the first transmission layer, and the first information is used to indicate one or more of the following: the network device does not cancel the first interference and the second interference; the network device cancels the first interference; the network device cancels the second interference; or the network device cancels both the first interference and the second interference.

[0336] In some embodiments, the first information includes a demodulation reference signal (DMRS) port index, and the DMRS port index is used to indicate whether the network device cancels interference between the multiple transmission layers.

[0337] In some embodiments, one DMRS port group includes multiple DMRS ports, one DMRS port group corresponds to multiple DMRS port indexes, and the multiple DMRS port indexes correspond to multiple interference cancellation manners one-to-one, and the interference cancellation manner is a manner in which the network device cancels interference between the multiple transmission layers.

[0338] In some embodiments, the determining the first information includes receiving capability information of the terminal device, the capability information being used to indicate a capability of the terminal device to cancel interference between the multiple transmission layers, and determining the first information based on the capability information.

[0339] In some embodiments, the interference between the plurality of transmission layers comprises a third interference, and the determining the first information based on the capability information comprises: in a case that the capability information indicates that the terminal device has the capability of canceling the third interference, the first information is used to indicate that the network device cancels other interference in the interference between the plurality of transmission layers except the third interference.

[0340] In some embodiments, the plurality of transmission layers comprises a first transmission layer and a second transmission layer, the first transmission layer corresponds to a first codeword, and the second transmission layer corresponds to a second codeword, and the first information is used to indicate one or more of the following: the codeword associated with the first channel state information is the first codeword; the codeword associated with the first channel state information is the second codeword; or the codeword associated with the first channel state information comprises the first codeword and the second codeword.

[0341] In some embodiments, the first information comprises a first transport block field and / or a second transport block field, if the first transport block field indicates that a first transport block is disabled, and a first subfield of the first transport block field takes a first value, then the codeword associated with the first channel state information is the second codeword; if the second transport block field indicates that a second transport block is disabled, and a first subfield of the second transport block field takes the first value, then the codeword associated with the first channel state information is the first codeword; if the first transport block field indicates that the first transport block is disabled, and the first subfield in the first transport block field takes a second value, then the codeword associated with the first channel state information comprises the first codeword and the second codeword; if the second transport block field indicates that the second transport block is disabled, and the first subfield in the second transport block field takes the second value, then the codeword associated with the first channel state information comprises the first codeword and the second codeword.

[0342] In some embodiments, the first subfield is a new data indicator (NDI) field.

[0343] In some embodiments, the processing unit 520 is configured to determine a precoding weight corresponding to a transmission layer based on the first information.

[0344] In some embodiments, in a case that a number of transmission layers between the network device and the terminal device is greater than A, the first information is used to indicate whether the network device cancels the interference between the plurality of transmission layers; and / or in a case that the number of transmission layers between the network device and the terminal device is less than or equal to A, the first information is used to indicate the codeword associated with the first channel state information; wherein A is a positive integer.

[0345] In some embodiments, the number of transmission layers corresponding to the first codeword is n, the number of transmission layers corresponding to the second codeword is m, and the A is the maximum of m and n.

[0346] In some embodiments, the first information is carried in radio resource control (RRC) signaling or downlink control information (DCI).

[0347] It should be understood that the "units" in the apparatus 500 can be implemented by hardware, or by software, or by hardware executing corresponding software. For example, the "units" can refer to application specific integrated circuits (ASIC), electronic circuits, processors (for example, shared processors, dedicated processors, or group processors, etc.) and memories for executing one or more software or firmware programs, integrated logic circuits, and / or other suitable components for supporting the described functions. For another example, the transceiving unit 510 can be replaced by a transceiver circuit (for example, which can include a receiving circuit and a transmitting circuit), and the processing unit 520 can be replaced by a processor or a processing circuit.

[0348] FIG. 6 is a schematic block diagram of another communication apparatus provided by embodiments of the present application. The communication apparatus 600 can be a terminal device / network device, or a chip, chip system, or processor, etc. implemented in a terminal device / network device for implementing the above-described methods. The apparatus can be used to implement the methods described in the above-described method embodiments, and specific implementation can be referred to the descriptions in the above-described method embodiments.

[0349] The communication apparatus 600 can include one or more processors 610, which can also be referred to as processing units, and can implement certain control functions. The processor 610 can be a general purpose processor or a special purpose processor, etc. For example, it can be a baseband processor or a central processing unit. The baseband processor can be used to process communication protocols and communication data, and the central processing unit can be used to control the communication apparatus, execute software programs, and process data of the software programs.

[0350] In an alternative design, the processor 610 can also store instructions and / or data, which can be executed by the processor 610, so that the communication apparatus 600 performs the methods described in the above-described method embodiments.

[0351] In another alternative design, the communication device 600 can include a communication interface 620 for implementing the receiving and transmitting functions. For example, the communication interface 620 can be a transceiver circuit, an interface, an interface circuit, or a transceiver, etc. The transceiver circuit, the interface, the interface circuit, or the transceiver for implementing the receiving and transmitting functions can be separate or integrated together. The transceiver circuit, the interface, the interface circuit, or the transceiver described above can be used for reading and writing of codes / data, or the transceiver circuit, the interface, the interface circuit, or the transceiver described above can be used for transmission or transfer of signals.

[0352] Optionally, the communication device 600 can include one or more memories 630, which can store instructions executable by the processor 610 to cause the communication device 600 to perform the methods described in the above method embodiments. Optionally, the memory 630 can also store data. Optionally, the processor 610 can also store instructions and / or data. The processor 610 and the memory 630 can be separately arranged or integrated together.

[0353] It should be understood that, in a possible design, each step in the method embodiments provided by the embodiments of the present application can be completed by integrated logic circuits of hardware in the processor or 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 completed by a hardware processor, or completed by a combination of hardware and software modules in the processor. The software module can be located in a random access memory, a flash memory, a read-only memory, a programmable read-only memory, an electrically erasable programmable memory, a register, or other mature storage mediums in the art. The storage medium is located in the memory, and the processor reads information in the memory and combines the hardware to complete the steps of the above method. To avoid repetition, it will not be described in detail here.

[0354] It should be noted that the processor in the embodiments of the present application can be an integrated circuit chip with a signal processing capability. In the implementation process, the steps of the above method embodiments can be completed by an integrated logic circuit or an instruction in the form of software in the processor. The processor described above can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. The disclosed methods, steps and logic block diagrams in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor or the like. The steps of the method disclosed in conjunction with the embodiments of the present application can be directly embodied as a hardware code processor for execution, or a combination of hardware and software modules in the code processor for execution. The software module can be located in a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register or other mature storage medium in the art. The storage medium is located in the storage, and the processor reads the information in the storage, and combines the hardware to complete the steps of the above method.

[0355] It can be understood that the memory in the embodiments of the present application can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memories. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically EPROM (EEPROM) or a flash memory. The volatile memory can be a random access memory (RAM) used as an external cache. By way of example but not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchlink DRAM (SLDRAM) and direct rambus RAM (DR RAM). It should be noted that the memory of the system and method described herein is intended to include but not limited to these and any other suitable types of memory.

[0356] The embodiments of the present application further provide a computer program product, which comprises computer program codes, and when the computer program codes are run on a computer, the computer is enabled to perform each step or procedure performed by the terminal device / network device in any of the above method embodiments.

[0357] The embodiments of the present application further provide a computer readable storage medium, which stores program codes, and when the program codes are run on a computer, the computer is enabled to perform each step or procedure performed by the terminal device / network device in any of the above method embodiments.

[0358] The embodiments of the present application further provide a communication apparatus, which comprises a processor and an interface for sending and / or receiving signals, so that the processor performs each step or procedure performed by the terminal device / network device in any of the above method embodiments.

[0359] The above apparatus embodiments and method embodiments correspond completely, and the corresponding steps are performed by the corresponding modules or units, for example, the steps of receiving or sending in the method embodiments are performed by the communication unit or the communication interface, and the other steps except for sending and receiving can be performed by the processing unit or the processor.

[0360] In the embodiments of the present application, each term and English abbreviation is an exemplary example given for convenience of description, and should not constitute any limitation to the present application. The embodiments of the present application do not exclude the possibility of defining other terms capable of realizing the same or similar functions in the existing or future protocols.

[0361] The terms "component", "module", "system", and the like used in the present specification are used to represent computer-related entities, hardware, combinations of hardware and software, software, or software in execution. For example, a component can be, but is not limited to, a process running on a processor, a processor, an object, an executable, a thread of execution, a program, and / or a computer. By way of illustration, both an application running on a computing device and the computing device can be a component. One or more components can reside within a process and / or thread of execution, and a component can be localized on one computer and / or distributed between two or more computers. In addition, these components can execute from various computer readable media having various data structures stored thereon. The components can communicate by way of local and / or remote processes such as in accordance with a signal having one or more data packets (e.g., data from one component interacting with another component in a local system, distributed system, and / or across a network such as the Internet with other systems via the signal), by way of the data packets, and / or by way of other signals in the various embodiments.

[0362] Those of skill in the art would understand that the various illustrative logical blocks and steps described in connection with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or combinations of both. The disclosure is not limited to implementations set forth herein for the sake of providing an overall understanding of architectures, suitability, and alternatives thereof. Those of skill would further understand that the functionality of various illustrative logical blocks and steps can be carried out by one or more electrical circuits, microprocessors, or gate arrays designed with source or object code, by a programmed computer, or by a combination thereof. Such functionality can be carried out in various ways, depending inter alia on the particular application for which the disclosure is employed, the design choices, and available technology. Skilled artisans can employ a variety of different approaches to implement the described functionality, and all combinations of these approaches are contemplated.

[0363] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described system, device and unit can be based on the corresponding processes in the foregoing method embodiments, which will not be repeated here.

[0364] In several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other ways. For example, the above-described device embodiments are merely illustrative, for example, the division of the units is only a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some interface, device or unit, and can be electrical, mechanical or other forms.

[0365] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, that is, they can be located in one place, or can be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0366] In addition, each functional unit in each embodiment of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit.

[0367] In the above embodiments, the functions of the various functional units can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, the software can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions (programs). When the computer program instructions (programs) are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are wholly or partially generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another, for example, the computer instructions can be transferred from one website, computer, server or data center to another via wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) manner. The computer-readable storage medium can be any available medium accessible by a computer or a data storage device such as a server, data center, etc. integrated with one or more available media. The available media can be magnetic media (for example, floppy disk, hard disk, magnetic tape), optical media (for example, DVD), or semiconductor media (for example, solid state disk (SSD)) and the like.

[0368] When the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of the embodiments of the present application essentially or the parts that make contributions to the prior art or parts of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various media that can store program codes.

[0369] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A communication method characterized by comprising: Comprising: receiving first information, the first information being used for indicating whether a network device cancels interference between multiple transmission layers, the multiple transmission layers corresponding to different codewords, or the first information being used for indicating a codeword associated with first channel state information, the first channel state information being used for precoding downlink information; receiving the downlink information based on the first information.

2. The method of claim 1, wherein, The multiple transmission layers include a first transmission layer and a second transmission layer, interference of the first transmission layer to the second transmission layer is a first interference, and interference of the second transmission layer to the first transmission layer is a second interference, The first information is used for indicating one or more of: The network device does not cancel the first interference and the second interference; The network device cancels the first interference; The network device cancels the second interference; Or The network device cancels the first interference and the second interference.

3. The method according to claim 1 or 2, characterized in that, The first information includes a demodulation reference signal (DMRS) port index, the DMRS port index being used for indicating whether the network device cancels interference between the multiple transmission layers.

4. The method of claim 3, wherein, One DMRS port group includes multiple DMRS ports, one DMRS port group corresponds to multiple DMRS port indexes, and multiple DMRS port indexes correspond to multiple interference cancellation manners one by one, the interference cancellation manner being a manner in which the network device cancels interference between the multiple transmission layers.

5. The method according to any one of claims 1-4, characterized in that, Before the receiving first information, the method further includes: sending capability information of a terminal device, the capability information being used for indicating a capability of the terminal device in cancelling interference between the multiple transmission layers.

6. The method of claim 1, wherein, The multiple transmission layers include a first transmission layer and a second transmission layer, a codeword corresponding to the first transmission layer is a first codeword, and a codeword corresponding to the second transmission layer is a second codeword, the first information being used for indicating one or more of: The codeword associated with the first channel state information is the first codeword; The codeword associated with the first channel state information is the second codeword; or The codeword associated with the first channel state information includes the first codeword and the second codeword.

7. The method of claim 6, wherein, The first information includes a first transport block field and / or a second transport block field, If the first transport block field indicates that a first transport block is disabled, and a first subfield of the first transport block field takes a first value, the codeword associated with the first channel state information is the second codeword; If the second transport block field indicates that a second transport block is disabled, and a first subfield of the second transport block field takes a first value, the codeword associated with the first channel state information is the first codeword; If the first transport block field indicates that the first transport block is disabled, and a first subfield in the first transport block field takes a second value, the codeword associated with the first channel state information includes the first codeword and the second codeword; If the second transport block field indicates that the second transport block is disabled, and a first subfield in the second transport block field has a second value, a code word associated with the first channel state information includes the first code word and the second code word.

8. The method of claim 7, wherein, The first subfield is a new data indicator (NDI) field.

9. The method of any of claims 1-8, wherein, in a case that a number of transmission layers between the network device and the terminal device is greater than A, the first information is used to indicate whether the network device cancels interference between the plurality of transmission layers; and / or in a case that the number of transmission layers between the network device and the terminal device is less than or equal to A, the first information is used to indicate a code word associated with the first channel state information; wherein A is a positive integer.

10. The method of claim 9, wherein, a number of transmission layers corresponding to the first code word is n, a number of transmission layers corresponding to the second code word is m, and the A is a maximum value of m and n.

11. The method according to any one of claims 1-10, characterized in that, The first information is carried in radio resource control (RRC) signaling or downlink control information (DCI).

12. A communication method characterized by comprising: including: determining first information, the first information being used to indicate whether a network device cancels interference between a plurality of transmission layers of a terminal device, or the first information being used to indicate a code word associated with first channel state information, wherein the first channel state information is used to precode downlink information; transmitting the first information.

13. The method of claim 12, wherein, The plurality of transmission layers includes a first transmission layer and a second transmission layer, interference of the first transmission layer to the second transmission layer is first interference, and interference of the second transmission layer to the first transmission layer is second interference, The first information is used to indicate one or more of: the network device does not cancel the first interference and the second interference; the network device cancels the first interference; the network device cancels the second interference; or the network device cancels the first interference and the second interference.

14. The method according to claim 12 or 13, characterized in that, The first information includes a demodulation reference signal (DMRS) port index, and the DMRS port index is used to indicate whether the network device cancels interference between the plurality of transmission layers.

15. The method of claim 14, wherein, One DMRS port group includes a plurality of DMRS ports, one DMRS port group corresponds to a plurality of DMRS port indexes, the plurality of DMRS port indexes correspond to a plurality of interference cancellation modes one by one, and the interference cancellation mode is a mode in which the network device cancels interference between the plurality of transmission layers.

16. The method according to any one of claims 12-15, characterized in that, The determination of the first information includes: receiving capability information of the terminal device, the capability information being used to indicate a capability of the terminal device to cancel interference between the plurality of transmission layers; determining the first information based on the capability information.

17. The method of claim 16, wherein, The interference between the plurality of transmission layers includes third interference, and the determination of the first information based on the capability information includes: in a case that the capability information indicates that the terminal device has a capability to cancel the third interference, the first information is used to indicate that the network device cancels interference other than the third interference between the plurality of transmission layers.

18. The method of claim 12, wherein, The multiple transmission layers include a first transmission layer and a second transmission layer, the first transmission layer corresponds to a first codeword, and the second transmission layer corresponds to a second codeword; the first information is used to indicate one or more of the following: The codeword associated with the first channel state information is the first codeword; The codeword associated with the first channel state information is the second codeword; or The codeword associated with the first channel state information includes the first codeword and the second codeword.

19. The method of claim 18, wherein, The first information includes a first transport block field and / or a second transport block field, If the first transport block field indicates that the first transport block is disabled, and a first subfield of the first transport block field takes a first value, the codeword associated with the first channel state information is the second codeword; If the second transport block field indicates that the second transport block is disabled, and a first subfield of the second transport block field takes a first value, the codeword associated with the first channel state information is the first codeword; If the first transport block field indicates that the first transport block is disabled, and a first subfield of the first transport block field takes a second value, the codeword associated with the first channel state information includes the first codeword and the second codeword; If the second transport block field indicates that the second transport block is disabled, and a first subfield of the second transport block field takes a second value, the codeword associated with the first channel state information includes the first codeword and the second codeword.

20. The method of claim 19, wherein, The first subfield is a new data indicator (NDI) field.

21. The method of any one of claims 18-20, wherein, The method further includes: Determining a precoding weight corresponding to a transmission layer based on the first information.

22. The method of any of claims 12-21, wherein, In a case where a number of transmission layers between the network device and the terminal device is greater than A, the first information is used to indicate whether the network device cancels interference between the multiple transmission layers; and / or In a case where the number of transmission layers between the network device and the terminal device is less than or equal to A, the first information is used to indicate a codeword associated with the first channel state information; where A is a positive integer. A number of transmission layers corresponding to the first codeword is n, a number of transmission layers corresponding to the second codeword is m, and the A is a maximum value of m and n.

23. The method of claim 22, wherein, The first information is carried in radio resource control (RRC) signaling or downlink control information (DCI).

24. The method of any one of claims 12-23, wherein, The apparatus includes units configured to perform respective steps of the method of any of claims 1-11, or units configured to perform respective steps of the method of any of claims 12-24.

25. A communications device, characterized by The apparatus includes a processor coupled to a memory, the memory storing a program or instructions that, when executed by the processor, cause the apparatus to perform the method of any of claims 1-11 or 12-24.

26. A communications device, characterized by The apparatus includes a processor and an interface configured to transmit and / or receive signals, such that the processor performs the method of any of claims 1-11 or 12-24.

27. A communications device, characterized by ​ 28. A readable storage medium, on which a computer program or instructions are stored, characterized in that, The computer program or instructions, when executed, cause the computer to perform the method of any one of claims 1-11 or any one of claims 12-24.

29. A computer program product, characterised in that, comprise computer program instructions to cause the computer to perform the method of any one of claims 1-11 or any one of claims 12-24.

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