A method and device for configuring a demodulation reference signal

Abstract

The present invention discloses a method and apparatus for configuring demodulation reference signals. The method includes: when it is determined that the precoding matrix used for a user in the current subframe has not been updated relative to the precoding matrix used for the user in the previous subframe of the current subframe, configuring a resource mapping pattern including M demodulation reference signals on the unit time-frequency resource block of the current subframe; where M < N, both M and N are positive integers, and N is the number of demodulation reference signals configured on the unit time-frequency resource block of the current subframe when the precoding matrix of the current subframe is updated. The present invention can effectively reduce the resource overhead of DMRS, improve the data transmission efficiency and system capacity, and solve the problems of the prior art.

Description

Technical Field

[0001] The present invention relates to the field of multi-carrier wireless communication, and particularly to a method and apparatus for configuring demodulation reference signals. Background Art

[0002] Long Term Evolution (LTE) technology is the fourth-generation (4G) wireless cellular communication technology. The LTE system introduces Demodulation Reference Signals (DMRS) for channel estimation at the receiving end. Moreover, it continues to be used in the fifth-generation (5G) wireless cellular communication technology.

[0003] The transmission of DMRS requires certain resource overheads, and the number of DMRS configured on a unit time-frequency resource block is fixed. In some application scenarios with good channel conditions, such as stationary, slow speed, and the presence of multiple direct line-of-sight paths, the same number of DMRS as in the general scenario is still used for channel estimation, wasting system resources. Summary of the Invention

[0004] Embodiments of the present invention provide a method and apparatus for configuring demodulation reference signals to solve the following problems in the prior art: in some application scenarios with good channel conditions, the same number of DMRS as in the general scenario is still used for channel estimation, wasting system resources.

[0005] On the one hand, embodiments of the present invention provide a method for configuring demodulation reference signals, including: when it is determined that the precoding matrix used for a user in the current subframe has not been updated relative to the precoding matrix used for the user in the previous subframe of the current subframe, configuring a resource mapping pattern including M demodulation reference signals on the unit time-frequency resource block of the current subframe; where M < N, both M and N are positive integers, and N is the number of demodulation reference signals configured on the unit time-frequency resource block of the current subframe when the precoding matrix of the current subframe is updated.

[0006] On the other hand, embodiments of the present invention also provide a storage medium storing a computer program, and when the computer program is executed by a processor, the steps of the above method for configuring demodulation reference signals are implemented.

[0007] On the other hand, an embodiment of the present invention further provides a device for configuring demodulation reference signals, including: a first configuration module, configured to configure a resource mapping pattern including M demodulation reference signals on a unit time-frequency resource block of the current subframe when it is determined that the precoding matrix used for a user in the current subframe has not been updated relative to the precoding matrix used for the user in the previous subframe of the current subframe; where M < N, both M and N are positive integers, and N is the number of demodulation reference signals configured on the unit time-frequency resource block of the current subframe when the precoding matrix of the current subframe is updated.

[0008] On the other hand, an embodiment of the present invention further provides a transmitting device, including the above device for configuring demodulation reference signals.

[0009] In the embodiment of the present invention, the precoding matrix used for a user in the current subframe is compared with the precoding matrix used for the user in the previous subframe. When the precoding matrix has not been updated, a resource mapping pattern of demodulation reference signals with the number of demodulation reference signals less than that when the precoding matrix is updated is configured. However, in the prior art, regardless of whether the precoding matrix is updated, the same number of DMRSs are used for channel estimation without any adjustment to the number of DMRSs. By applying the embodiment of the present invention, the resource overhead of DMRS can be effectively reduced, the data transmission efficiency and system capacity can be improved, and the following problem of the prior art is solved: in some application scenarios with good channel conditions, the same number of DMRSs as in the general scenario are still used for channel estimation, wasting system resources. Description of the Drawings

[0010] Figure 1 is a flowchart of a method for configuring demodulation reference signals in the first embodiment of the present invention;

[0011] Figure 2 is a schematic structural diagram of a device for configuring demodulation reference signals in the second embodiment of the present invention;

[0012] Figure 3 is a schematic diagram of a resource mapping pattern including 12 DMRSs in the third embodiment of the present invention;

[0013] Figure 4 is a schematic diagram of a resource mapping pattern including 4 DMRSs in the third embodiment of the present invention;

[0014] Figure 5 is a schematic diagram of a resource mapping pattern including 8 DMRSs in the third embodiment of the present invention. Detailed Embodiments

[0015] To solve the following problems of the prior art: in some application scenarios with good channel conditions, the same number of DMRSs as in the general scenario are still used for channel estimation, wasting system resources; the present invention provides a method and device for configuring demodulation reference signals. The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not limit the present invention.

[0016] The first embodiment of the present invention provides a method for configuring demodulation reference signals. The flow of the method is as Figure 1 shown, including steps S102 to S104:

[0017] S102, determining whether the precoding matrix used for the user in the current subframe is updated relative to the precoding matrix used for the user in the previous subframe of the current subframe;

[0018] S104, when the precoding matrix of the current subframe is not updated, configuring a resource mapping pattern including M demodulation reference signals on the unit time-frequency resource block of the current subframe;

[0019] wherein, M < N, both M and N are positive integers, and N is the number of demodulation reference signals configured on the unit time-frequency resource block of the current subframe when the precoding matrix of the current subframe is updated.

[0020] During implementation, when the precoding matrix of the current subframe is updated, a resource mapping pattern including N demodulation reference signals is configured on the unit time-frequency resource block of the current subframe.

[0021] For the case where the precoding matrix is not updated, considering saving system resources, the number of demodulation reference signals can be reduced. Therefore, the number M of demodulation reference signals in the case where the precoding matrix is not updated in this embodiment is less than the number N of demodulation reference signals in the case where the precoding matrix is updated.

[0022] The embodiment of the present invention compares the precoding matrix used for the user in the current subframe with the precoding matrix used for the user in the previous subframe. When the precoding matrix is not updated, the number of configured demodulation reference signals is less than the number of demodulation reference signals when the precoding matrix is updated. However, in the prior art, regardless of whether the precoding matrix is updated, the same number of DMRSs are used for channel estimation without any adjustment to the number of DMRSs.

[0023] By applying this embodiment, the resource overhead of DMRS can be effectively reduced, data transmission efficiency and system capacity can be improved, and the following problems in the prior art are solved: in some application scenarios with good channel conditions, the same number of DMRS as in general scenarios is still used for channel estimation, wasting system resources.

[0024] During configuration, the number of demodulation reference signals M contained in the resource mapping pattern can be set to a lower limit, that is, M is greater than or equal to K. In specific implementation, K represents the number of data transmission layers of the current subframe, and K is a positive integer. The purpose of this process is to ensure that the channel estimation of the K-layer transmission data can be carried out normally, and to avoid the situation where the channel estimation cannot be performed due to too few demodulation reference signals.

[0025] In the case of a multi-user spatial multiplexing transmission mode, the process of determining whether an update occurs is for all current users. Therefore, when determining whether a precoding matrix used for a user in a current subframe is updated relative to a precoding matrix used for a user in a subframe previous to the current subframe, it is specifically determined whether a precoding matrix used by all users of multi-user spatial multiplexing in the current subframe is updated relative to a precoding matrix used by all users in a previous subframe.

[0026] If the precoding matrix of one or more users is updated, it is confirmed that the precoding matrix of the current subframe is updated relative to the previous subframe. If the precoding matrix of each user is not updated, it is confirmed that the precoding matrix of the current subframe is not updated relative to the previous subframe. After confirming whether an update has occurred, the corresponding operation can be performed according to the update situation.

[0027] During the implementation process, between the current precoding matrix being updated and the next precoding matrix being updated, resource mapping patterns of demodulation reference signals of the same number are configured on unit time-frequency resource blocks of all subframes in which precoding has not been updated; or, between the current precoding matrix being updated and the next precoding matrix being updated, resource mapping patterns of demodulation reference signals of different numbers are configured on unit time-frequency resource blocks of all subframes in which precoding has not been updated.

[0028] On the unit time-frequency resource blocks of subframes where all precoding does not change, when configuring resource mapping patterns of demodulation reference signals with different numbers, it is possible to configure the number of demodulation reference signals included in the resource mapping pattern of the demodulation reference signal to increase or decrease as the subframe number increases. For example, configure resource mapping patterns containing 2, 4, 6, 8, and 10 DMRSs for the 2nd to 6th subframes where the precoding matrix does not change respectively. Another example, configure resource mapping patterns containing 2, 3, 4, 5, and 6 DMRSs for the 2nd to 6th subframes where the precoding matrix does not change respectively; or, configure the number of demodulation reference signals included in the resource mapping pattern of the demodulation reference signal to increase or decrease cyclically by a predetermined number within a predetermined number of subframes. For example, configure resource mapping patterns containing 2, 4, 6, 2, 4, and 6 DMRSs for the 2nd to 7th subframes where the precoding matrix does not change respectively. Another example, configure resource mapping patterns containing 6, 4, 2, 6, 4, and 2 DMRSs for the 2nd to 7th subframes where the precoding matrix does not change respectively.

[0029] The second embodiment of the present invention provides a device for configuring demodulation reference signals. The structural schematic of the device is as Figure 2 shown, including:

[0030] A determination module 10, configured to determine whether the precoding matrix used for the user in the current subframe is updated relative to the precoding matrix used for the user in the previous subframe of the current subframe; a first configuration module 11, coupled to the determination module 10, configured to, when the precoding matrix of the current subframe is not updated, configure a resource mapping pattern containing M demodulation reference signals on the unit time-frequency resource block of the current subframe; where M < N, both M and N are positive integers, and N is the number of demodulation reference signals configured on the unit time-frequency resource block of the current subframe when the precoding matrix of the current subframe is updated.

[0031] The above device may further include a second configuration module, also coupled to the determination module, configured to, when the precoding matrix of the current subframe is updated, configure a resource mapping pattern containing N demodulation reference signals on the unit time-frequency resource block of the current subframe.

[0032] In the embodiment of the present invention, the precoding matrix used for the user in the current subframe is compared with the precoding matrix used for the user in the previous subframe to determine whether the precoding matrix is updated. When the precoding matrix is not updated, a resource mapping pattern of demodulation reference signals with the number of demodulation reference signals less than that when the precoding matrix is updated is configured.

[0033] Among them, the number M of demodulation reference signals included in the resource mapping pattern configured by the first configuration module is greater than or equal to K, where K indicates that the data transmission in the current subframe is K-layer data transmission, and K is a positive integer.

[0034] In the case of a multi-user spatial multiplexing transmission mode, the process of determining whether an update occurs is for all current users. The above-mentioned determination module is specifically used to detect whether the precoding matrix used by all users of multi-user spatial multiplexing in the current subframe is updated relative to the precoding matrix used by all users in the previous subframe when the user is in a multi-user spatial multiplexing transmission mode.

[0035] If the precoding matrix of one or more users is updated, it is confirmed that the precoding matrix of the current subframe is updated relative to the previous subframe. If the precoding matrix of each user is not updated, it is confirmed that the precoding matrix of the current subframe is not updated relative to the previous subframe. After confirming whether the update occurs, the first configuration module or the second configuration module can be triggered to work according to the update situation.

[0036] The above-mentioned device may also include: a third configuration module, which is used to configure the same number of resource mapping patterns of demodulation reference signals on the unit time-frequency resource blocks of all subframes in which the precoding has not been updated between the current precoding matrix being updated and the next precoding being updated; and a fourth configuration module, which is used to configure different numbers of resource mapping patterns of demodulation reference signals on the unit time-frequency resource blocks of all subframes in which the precoding has not been updated between the current precoding matrix being updated and the next precoding being updated.

[0037] In specific implementation, the fourth configuration module is specifically used to configure the number of demodulation reference signals contained in the resource mapping pattern of the demodulation reference signal to increase or decrease as the subframe number increases, or to configure the number of demodulation reference signals contained in the resource mapping pattern of the demodulation reference signal to cyclically increase or cyclically decrease according to a predetermined number in a predetermined number of subframes. For example, the resource mapping patterns containing 2, 4, 6, and 8 DMRS are configured for the 2nd to 5th subframes in which the precoding matrix is ​​not updated, respectively; for another example, the resource mapping patterns containing 5, 4, 3, and 2 DMRS are configured for the 2nd to 5th subframes in which the precoding matrix is ​​not updated, respectively; for another example, the resource mapping patterns containing 2, 4, 6, 2, 4, and 6 DMRS are configured for the 2nd to 7th subframes in which the precoding matrix is ​​not updated, respectively, etc.

[0038] The device provided by the embodiment of the present invention can effectively reduce the resource overhead of DMRS, thereby ensuring good channel estimation performance, improving data transmission efficiency and system capacity, and solving the following problems of the prior art: in some application scenarios with better channel conditions, the same number of DMRS is still used for channel estimation as in application scenarios with poorer channel conditions, wasting system resources.

[0039] The LTE system introduces DMRS for channel estimation at the receiving end. The transmission of DMRS requires a certain amount of resource overhead, and the number of DMRS configured per unit time-frequency resource block is fixed. However, for some application scenarios with very good channel conditions, such as static or slow speed, and the presence of multiple direct lines of sight, a small amount of DMRS can still guarantee the performance of channel estimation.

[0040] To this end, the third example of the present invention proposes a DMRS configuration method for reducing resource overhead. The method can effectively reduce DMRS overhead and improve data transmission efficiency.

[0041] The implementation process of the present invention is described in detail below through several specific examples.

[0042] In a first example of the present invention, a DMRS configuration method is provided, which can be applied to a transmitting node, and the transmitting node can be but is not limited to: a base station, a terminal, a relay, a transmitting point, etc. The method comprises the following steps:

[0043] Step S1, determining whether a precoding matrix used for a user in a subframe is updated relative to a precoding matrix used for the user in a previous subframe.

[0044] In the example of the present invention, whether the precoding matrix is ​​updated refers to whether the precoding matrix is ​​changed, that is, whether the precoding matrix used by the user in the subframe is changed relative to the precoding matrix used by the user in the previous subframe.

[0045] In the embodiment of the present invention, the user includes a single user or multiple users. Specifically, when the user is single user multiple input multiple output spatial multiplexing (SU-MIMO), the user refers to a single user; when the user is multiple users multiple input multiple output spatial multiplexing (MU-MIMO), the user refers to multiple users multiplexed by MU-MIMO.

[0046] The number of time-frequency resource blocks contained in the above-mentioned single subframe is equal to the number of time-frequency resource blocks occupied by the user.

[0047] In the example of the present invention, the duration of a single subframe is a unit time length, which can be the duration of a subframe in the LTE system, or the transmission time interval (TTI) of a data block, or another time concept defined by the system.

[0048] Step S2: For a subframe in which the precoding matrix is updated, configure a resource mapping pattern including N DMRSs on the unit time-frequency resource block of the subframe; for a subframe in which the precoding matrix is not updated, configure a resource mapping pattern including M DMRSs on the unit time-frequency resource block of the subframe. Herein, M < N, and M and N are positive integers.

[0049] In an example of the present invention, the unit time-frequency resource block represents a single time-frequency resource block (RB, Resource Block). The width of the unit time-frequency resource block in the time domain is t, and the number of subcarriers included in the frequency domain is n. t is a time length greater than 0, and n is an integer greater than 1. In the LTE system, t = 1 millisecond and n = 12.

[0050] In this example, in the case of multi-user spatial multiplexing transmission mode, determine whether the precoding matrix used by all users in multi-user spatial multiplexing within a subframe is updated relative to the precoding matrix used by all users in the previous subframe; for a subframe in which the precoding matrix used by all users is not updated, configure a resource mapping pattern including M DMRSs on the unit time-frequency resource block of the subframe.

[0051] Specifically, when the user is MU-MIMO, the user represents all users multiplexed by MU-MIMO. If the precoding matrix used by any user in MU-MIMO is updated in a subframe, then configure a resource mapping pattern including N DMRSs on the unit time-frequency resource block of the subframe; if the precoding matrix used by all users in MU-MIMO is not updated in the subframe, then configure a resource mapping pattern including M DMRSs on the unit time-frequency resource block of the subframe.

[0052] In an example of the present invention, for a subframe in which the precoding matrix is not updated, when the subframe is for K-layer data transmission, the number of DMRSs included in the resource mapping pattern including M DMRSs is greater than or equal to K, that is, K ≤ M < N. Herein, K is a positive integer.

[0053] Specifically, for a subframe in which the precoding matrix is not updated, if the subframe is for single-layer data transmission, the number of DMRSs included in the resource mapping pattern of the unit time-frequency resource block is greater than or equal to 1; if the subframe is for double-layer data transmission, the number of DMRSs included in the resource mapping pattern of the unit time-frequency resource block is greater than or equal to 2; if the subframe is for three-layer data transmission, the number of DMRSs included in the resource mapping pattern of the unit time-frequency resource block is greater than or equal to 3. Similarly, and so on in sequence.

[0054] In a specific example of the present invention, N = 12 or 24.

[0055] In an embodiment of the present invention, between the update of the precoding matrix and the next update of the precoding matrix, for all consecutive subframes in which the precoding matrix does not change, the same DMRS resource mapping pattern is configured on the unit time-frequency resource block of the subframe.

[0056] For example, if the user updates the precoding matrix for single-layer transmission data in subframe 1, and the next update of the precoding matrix is in subframe 6, and the precoding matrix does not change in subframes 2, 3, 4, and 5, then the same resource mapping pattern including 2 DMRSs can be configured on subframes 2, 3, 4, and 5.

[0057] Optionally, in an embodiment of the present invention, between the update of the precoding matrix and the next update of the precoding matrix, for all consecutive subframes in which the precoding matrix does not change, different DMRS resource mapping patterns are configured on the unit time-frequency resource block of the subframe. Further, the number of DMRSs included in the DMRS resource mapping pattern increases or decreases cyclically as the subframe changes.

[0058] For example, if the user updates the precoding matrix for single-layer transmission data in subframe 1, and the next update of the precoding matrix is in subframe 11, and the precoding matrix does not change in subframes 2 to 10, then the resource mapping patterns including 2, 4, 6, 2, 4, 6, 2, 4, and 6 DMRSs can be configured on subframes 2 to 10 respectively, or the resource mapping patterns including 6, 4, 2, 6, 4, 2, 6, 4, and 2 DMRSs can be configured on subframes 2 to 10 respectively.

[0059] In summary, in the method of the embodiment of the present invention, a resource mapping pattern including N DMRSs is configured on the unit time-frequency resource block of the subframe in which the precoding matrix is updated; a resource mapping pattern including M DMRSs is configured on the unit time-frequency resource block of the subframe in which the precoding matrix does not change. Among them, M < N, and M and N are positive integers. In this way, the resource overhead of DMRS can be effectively reduced. At the same time, the receiving algorithm can use methods such as joint channel estimation between subframes to ensure good channel estimation performance, thereby improving data transmission efficiency and system capacity.

[0060] In a second embodiment of the present invention, a method for configuring DMRS is also provided. This embodiment is a specific implementation of the method of the first embodiment. Specifically, the method includes the following steps:

[0061] Step S1, determine whether the precoding matrix used for the user in the subframe in the downlink transmission is updated relative to the precoding matrix used for the user in the previous subframe.

[0062] Step S2: for a subframe where the precoding matrix is ​​updated, a resource mapping pattern including 12 DMRSs is configured on the unit time-frequency resource block of the subframe; for a subframe where the precoding matrix is ​​not updated, a resource mapping pattern including 4 DMRSs is configured on the unit time-frequency resource block of the subframe.

[0063] In the example of the present invention, a resource mapping pattern including 4 DMRSs is configured on a subframe where the precoding matrix is ​​not updated, which can support a maximum of 4 layers of data transmission.

[0064] In a specific example of the present invention, a resource mapping pattern including 12 DMRS is as follows: Figure 3 As shown; the resource mapping pattern including 4 DMRS is as follows Figure 4 shown.

[0065] In a specific example of the present invention, the user's precoding matrix is ​​updated in subframes 12 and 17. Then, the unit time-frequency resource blocks of subframes 12 and 17 are configured. Figure 3 The DMRS pattern shown is configured on the unit time-frequency resource blocks of subframes 13, 14, 15, and 16. Figure 4 The DMRS pattern shown.

[0066] Furthermore, the receiving algorithm can use a joint channel estimation method of up to three subframes to ensure good channel estimation performance. Specifically, for subframes 12, 13, 14, 15, and 16, the number of DMRS on their unit time-frequency resource blocks is 12, 4, 4, 4, and 4, respectively. Subframes 12 and 17 are subframes where the precoding matrix is ​​updated, and all subframes where the precoding matrix is ​​updated use separate subframe channel estimation; further, subframe 13 is combined with subframe 12 to perform a joint channel estimation of two subframes, subframe 14 is combined with subframes 12 and 13 to perform a joint channel estimation of three subframes, subframe 15 is combined with subframes 13 and 14 to perform a joint channel estimation of three subframes, and subframe 16 is combined with subframes 14 and 15 to perform a joint channel estimation of three subframes. In this way, each channel estimation has at least 12 DMRS joint channel estimates, which ensures the ability of the channel estimation to resist noise, while reducing the time-frequency resource overhead and improving data transmission efficiency.

[0067] In the third example of the present invention, a DMRS configuration method is also provided, which is a specific implementation of the method of the first example. Specifically, the method includes the following steps:

[0068] Step S1, determining whether a precoding matrix used for two-user MU-MIMO in a subframe during downlink transmission is updated relative to a precoding matrix used for two-user MU-MIMO in a previous subframe.

[0069] In the example of the present invention, two-user MU-MIMO is spatial multiplexing of two users. When determining whether the precoding matrix is ​​updated, it is necessary to determine whether the precoding matrix of each user is updated.

[0070] Step S2, for the subframe where the precoding matrix is ​​updated, a resource mapping pattern including 12 DMRS is configured on the unit time-frequency resource block of the subframe; for the subframe where the precoding matrix is ​​not updated, a resource mapping pattern including 8 DMRS or a resource mapping pattern including 4 DMRS is configured on the unit time-frequency resource block of the subframe.

[0071] In a specific example of the present invention, a resource mapping pattern including 12 DMRS is as follows: Figure 3 As shown; the resource mapping pattern including 4 DMRS is as follows Figure 4 As shown; the resource mapping pattern including 8 DMRS is as follows Figure 5 shown.

[0072] In an example of the present invention, if the precoding matrix of any of the two users of MU-MIMO in a subframe is updated, a pattern including 12 DMRS is configured on the unit time-frequency resource block of the subframe; if the precoding matrices of both users in the subframe are not updated, a pattern including 8 DMRS or a pattern including 4 DMRS is configured on the unit time-frequency resource block of the subframe.

[0073] In a specific example of the present invention, between the update of the precoding matrix and the next update of the precoding matrix, for all consecutive subframes in which the precoding matrix is ​​not updated, the subframes are alternately configured in sequence. Figure 4 The DMRSpattern and Figure 5 The DMRS pattern is shown.

[0074] Specifically, assume that the precoding matrix of user 1 is updated in subframes 8 and 18, and the precoding matrix of user 2 is updated in subframes 8 and 14. Then, configure the unit time-frequency resource blocks of subframes 8, 14, and 18 Figure 3 DMRS pattern shown; configured on the unit time-frequency resource blocks of subframes 9, 11, 13, 15, and 17 Figure 4 DMRS pattern shown; configured on the unit time-frequency resource blocks of subframes 10, 12, and 16 Figure 5 The DMRS pattern is shown.

[0075] Furthermore, the receiving algorithm can use a joint channel estimation method of up to two subframes to ensure good channel estimation performance. Specifically, the precoding matrix is ​​updated in subframe 8, the next precoding matrix is ​​updated in subframe 14, and the next precoding matrix is ​​updated in subframe 18. Then, for subframes 8, 9, 10, 11, 12, and 13, the number of DMRS on their unit time-frequency resource blocks is 12, 4, 8, 4, 8, and 4 respectively, and for subframes 14, 15, 16, and 17, the number of DMRS on their unit time-frequency resource blocks is 12, 4, 8, and 4 respectively. Among them, subframes 8, 14, and 18 are subframes where the precoding matrix is ​​updated, and all subframes where the precoding matrix is ​​updated use separate subframe channel estimation; further, subframe 9 is combined with subframe 8, subframe 10 is combined with subframe 9, subframe 11 is combined with subframe 10, subframe 12 is combined with subframe 11, and subframe 13 is combined with subframe 12 to perform joint channel estimation of two subframes, respectively; further, subframe 15 is combined with subframe 14, subframe 16 is combined with subframe 15, and subframe 17 is combined with subframe 16 to perform joint channel estimation of two subframes, respectively. In this way, each channel estimation has at least 12 DMRS joint channel estimates, which ensures the ability of the channel estimation to resist noise, while reducing the time-frequency resource overhead and improving the data transmission efficiency.

[0076] Through the description of the above implementation methods, those skilled in the art can clearly understand that the method according to the above example can be implemented by means of software plus a necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for a terminal device (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods of each example of the present invention.

[0077] Although preferred examples of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, and thus, the scope of the present invention should not be limited to the above examples.

Claims

1. A method for configuring a demodulation reference signal, characterized in that: Comprising: When it is determined that the precoding matrix used for the user in the current subframe has not been updated relative to the precoding matrix used for the user in the previous subframe of the current subframe, configuring a resource mapping pattern including M demodulation reference signals on the unit time-frequency resource block of the current subframe; Wherein, M < N, both M and N are positive integers, and N is the number of demodulation reference signals configured on the unit time-frequency resource block of the current subframe when the precoding matrix of the current subframe is updated; Wherein, whether the precoding matrix is updated means whether the precoding matrix has changed.

2. The configuration method according to claim 1, characterized in that: When it is determined that the precoding matrix used for the user in the current subframe has been updated relative to the precoding matrix used for the user in the previous subframe of the current subframe, configuring a resource mapping pattern including N demodulation reference signals on the unit time-frequency resource block of the current subframe.

3. The configuration method according to claim 1, characterized in that: The number M of demodulation reference signals included in the resource mapping pattern is greater than or equal to K, where K represents the number of data transmission layers in the current subframe, and K is a positive integer.

4. The configuration method according to claim 1, characterized in that: Configuring a resource mapping pattern including M demodulation reference signals on the unit time-frequency resource block of the current subframe further includes: When the user is a user in the multi-user spatial multiplexing transmission mode, determining whether the precoding matrices used by all users in the multi-user spatial multiplexing in the current subframe have been updated relative to the precoding matrices used by all users in the previous subframe.

5. The configuration method according to any one of claims 1 to 4, characterized in that: The method further includes: Between the current precoding matrix update and the next precoding matrix update, configuring resource mapping patterns with the same number of demodulation reference signals on the unit time-frequency resource blocks of all subframes where the precoding has not been updated; or, Between the current precoding matrix update and the next precoding matrix update, configuring resource mapping patterns with different numbers of demodulation reference signals on the unit time-frequency resource blocks of all subframes where the precoding has not been updated.

6. The configuration method according to claim 5, characterized in that: Configuring resource mapping patterns with different numbers of demodulation reference signals on the unit time-frequency resource blocks of all subframes where the precoding has not been updated includes: Configuring the number of demodulation reference signals included in the resource mapping pattern of the demodulation reference signals to increase as the subframe number increases or decrease as the subframe number increases, or configuring the number of demodulation reference signals included in the resource mapping pattern of the demodulation reference signals to increase or decrease cyclically according to a predetermined number in a predetermined number of subframes.

7. A configuration device for a demodulation reference signal, characterized in that: Comprising: A first configuration module, configured to, when it is determined that the precoding matrix used for the user in the current subframe has not been updated relative to the precoding matrix used for the user in the previous subframe of the current subframe, configure a resource mapping pattern including M demodulation reference signals on the unit time-frequency resource block of the current subframe; Wherein, M < N, both M and N are positive integers, and N is the number of demodulation reference signals configured on the unit time-frequency resource block of the current subframe when the precoding matrix of the current subframe is updated; Wherein, whether the precoding matrix is updated means whether the precoding matrix has changed.

8. The configuration device according to claim 7, characterized in that Further comprising: The second configuration module is used to configure a resource mapping pattern including N demodulation reference signals on a unit time-frequency resource block of the current subframe when it is determined that the precoding matrix used for the user in the current subframe is updated relative to the precoding matrix used for the user in the subframe before the current subframe.

9. The configuration device according to claim 7, characterized in that: The number M of demodulation reference signals included in the resource mapping pattern configured by the first configuration module is greater than or equal to K, where K represents the number of data transmission layers of the current subframe, and K is a positive integer.

10. The configuration device according to claim 7, characterized in that The device also includes: The determination module is used to determine, in the case of a multi-user spatial multiplexing transmission mode, whether the precoding matrix used by all users of the multi-user spatial multiplexing in the current subframe is updated relative to the precoding matrix used by all users in the previous subframe.

11. The configuration device according to any one of claims 7 to 10, characterized in that: The device also includes: A third configuration module is used to configure the same number of resource mapping patterns of demodulation reference signals on unit time-frequency resource blocks of all subframes in which precoding has not been updated between the current precoding matrix being updated and the next precoding matrix being updated; The fourth configuration module is used to configure resource mapping patterns of demodulation reference signals of different numbers on unit time-frequency resource blocks of all subframes in which precoding has not been updated between the current precoding matrix being updated and the next precoding matrix being updated.

12. The configuration device according to claim 11, characterized in that The fourth configuration module is specifically used to configure the number of demodulation reference signals included in the resource mapping pattern of the demodulation reference signal to increase or decrease with the increase of the subframe number, or to configure the number of demodulation reference signals included in the resource mapping pattern of the demodulation reference signal to cyclically increase or cyclically decrease according to a predetermined number in a predetermined number of subframes.

13. A transmitting device, characterized in that: include: The configuration device of the demodulation reference signal according to any one of claims 7 to 12.

14. A storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method for configuring a demodulation reference signal according to any one of claims 1 to 6 are implemented.

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