TW201818703A - Modulation mode detection method and device - Google Patents

Abstract

Disclosed are a modulation mode detection method and device. Embodiments of the present invention provide a modulation mode detection method and device, for use in solving the problem of difficulty in productization due to high complexity of an existing modulation mode blink detection scheme. The method comprises: performing joint detection on a receive signal vector according to a channel matrix for each candidate modulation mode to obtain accumulated branch metric vectors corresponding to each RE; performing summation on a minimum value in the accumulated branch metric vectors corresponding to each RE to obtain a minimum accumulated branch metric corresponding to the candidate modulation mode; and determining a minimum value from the minimum accumulated branch metrics corresponding to all the candidate modulation modes and determining the modulation mode corresponding to the determined minimum value as the modulation mode used by an interference cell.

Description

   Method and device for detecting modulation mode   

The present invention belongs to the field of communication technology, and particularly relates to a method and a device for detecting a modulation mode.

In the Long Term Evolution-Advanced (LTE-A) Release 12 (Rel 12) system, in order to improve the system throughput in an interference scenario, the network side will send relevant information about the interfering cell to the user through signaling. Equipment (UE), making it possible for the UE to perform network assisted interference cancellation and suppression (NAICS) capable of suppressing or deleting the physical downlink shared channel (PDSCH) interference of the interfering cell Detection. This is a joint reception scheme for the serving cell and the interfering cell. This receiver is called a NAICS receiver.

However, in the LTE / LTE-A network, some transmission parameters are dynamic parameters. If these parameters are kept unchanged during the signaling period and sent to the UE, the network side will lose flexibility. Therefore, the network side does not issue these dynamic parameters, and the UE needs to perform blind detection on these dynamic parameters. The modulation method used for the PDSCH transmission of the interfering cell is a key parameter for the UE to jointly detect the signal of the serving cell and the interfering cell. The parameter is also a dynamic parameter, and the network side does not issue the parameter to the UE. Therefore, the UE needs to perform blind detection on this parameter.

At present, NAICS receivers generally adopt the structure shown in Figure 1. A functional module for blind detection is required between the channel estimation module and the joint detection module. Does this module interfere with PDSCH, and the transmission mode and code? Parameters such as local, layer number, and modulation method are blindly detected. At present, the blind detection scheme of the modulation method is based on the available information, and the three types of modulation are Quadrature Phase Shift Keyihg (QPSK) \ 16 Quadrature Amplitude Modulation (16QAM) \ 64QAM The modulation method with the highest probability is selected from the methods.

The above scheme is a method for determining the maximum likelihood modulation method based on the likelihood information (Full Maximum Likelihood), which calculates the probability of different modulation modes for the interfering cell and selects the modulation method with the highest probability. Since it is necessary to calculate the probability that the interference cell is three modulation modes of QPSK / 16QAM / 64QAM, it is equivalent to doing three maximum likelihood detections, and the calculation amount is roughly three times that of the maximum likelihood detection. The complexity of maximum likelihood detection itself is very high. If a traditional receiver uses a maximum complexity maximum likelihood detection algorithm, adding a functional module for blind detection of modulation will make the receiver The overall complexity of the machine is extremely high.

In summary, the complexity of the existing blind detection schemes of modulation methods is high and it is difficult to achieve commercialization.

The embodiments of the present invention provide a modulation method detection method and device, which are used to solve the problem that the existing blind detection scheme of the modulation method has a high complexity and is difficult to achieve commercialization.

In a first aspect, a modulation method detection method is provided, which includes: for each candidate modulation method, joint detection of a received signal vector according to a channel matrix to obtain a cumulative branch metric vector corresponding to each resource element (RE) Sum the minimum values in the cumulative branch metric vector corresponding to each RE to obtain the minimum cumulative branch metric value corresponding to the candidate modulation method; determine the minimum value from the minimum cumulative branch metric value corresponding to each candidate modulation method And determine the modulation method corresponding to the determined minimum value as the modulation method used by the interfering cell.

In a possible implementation manner, for each candidate modulation method, the received signal vectors are jointly detected according to the channel matrix to obtain a cumulative branch metric vector corresponding to each RE, including: A tree search is performed on the signals to obtain the branch metric vector corresponding to each RE in the serving cell. According to the obtained branch metric vector, for each candidate modulation method, a tree search is performed on the signal transmitted at each layer of the interfering cell to obtain each Cumulative branch metric vector corresponding to RE; where the tree search represents the process of selecting the smallest M reserved branches layer by layer, and this branch represents the combination of candidate constellation symbols corresponding to each layer of the serving cell and each layer of the interfering cell.

In a possible implementation manner, if there are at least two interfering cells, according to the obtained branch metric vector, for each candidate modulation method, a tree search is performed on the signals transmitted at each layer of the interfering cell to obtain the accumulation corresponding to each RE. The branch metric vector includes: according to the obtained branch metric vector, for each candidate modulation mode, the signals transmitted at each layer of each interfering cell are sequentially processed in accordance with the signal receiving power of each interfering cell in order from large to small. Tree search to get the cumulative branch metric vector corresponding to each RE.

In a possible implementation manner, for each candidate modulation method, joint detection is performed on the received signal vector according to the channel matrix to obtain a cumulative branch metric vector corresponding to each RE, further including: for each candidate modulation method, according to the channel matrix , Performing joint detection on the received signal vector to obtain the reserved branch corresponding to each RE, wherein the reserved branch corresponding to each RE corresponds to the cumulative branch metric vector corresponding to the RE one to one; and the modulation method corresponding to the determined minimum value After determining the modulation mode used by the interfering cell, the method further includes: calculating and outputting a soft bit according to the modulation mode used by the interfering cell and a reserved branch corresponding to the determined minimum value.

In a possible implementation manner, the candidate modulation modes include: QPSK and 64QAM.

In a second aspect, a computer-readable storage medium is provided, in which executable program code is stored, which is used to implement the method described in the first aspect.

A third-party vendor provides a modulation mode detection device, which includes: a minimum cumulative branch metric determination module for joint detection of the received signal vector according to the channel matrix for each candidate modulation mode to obtain the accumulation corresponding to each RE. Branch metric vector; sum the minimum value of the cumulative branch metric vector corresponding to each RE to obtain the minimum cumulative branch metric value corresponding to the candidate modulation method; the modulation mode determination module is used to modulate from each candidate modulation A minimum value is determined from a minimum cumulative branch metric value corresponding to the mode, and a modulation mode corresponding to the determined minimum value is determined as a modulation mode used by the interfering cell.

In a possible implementation manner, the minimum cumulative branch metric determination module is specifically configured to: for each candidate modulation method, perform a tree search on the signals transmitted at each layer of the serving cell according to the channel matrix to obtain each RE under the serving cell. Corresponding branch metric vector; according to the obtained branch metric vector, for each candidate modulation method, a tree search is performed on the signals transmitted by the layers of the interfering cell to obtain the cumulative branch metric vector corresponding to each RE; Tree search represents the process of selecting the smallest M reserved branches layer by layer, and this branch represents the combination of candidate constellation symbols corresponding to each layer of the serving cell and each layer of the interfering cell.

In a possible implementation manner, if there are at least two interfering cells, the minimum cumulative branch metric determination module is specifically configured to: according to the obtained branch metric vector, for each candidate modulation mode, according to the signal of each interfering cell The received power is in descending order, and a tree search is performed on the signals transmitted at each layer of each interfering cell in order to obtain the cumulative branch metric vector corresponding to each RE.

In a possible implementation manner, the minimum cumulative branch metric determination module is further configured to: for each candidate modulation method, perform joint detection on the received signal vector according to the channel matrix to obtain the reserved branch corresponding to each RE, where each The reserved branch corresponding to each RE corresponds to the cumulative branch metric vector corresponding to the RE; the modulation mode determination module is further configured to calculate according to the modulation mode used by the interfering cell and the reserved branch corresponding to the determined minimum value. Soft bits are output.

In a possible implementation manner, the candidate modulation modes include: QPSK and 64QAM.

According to a fourth aspect, a modulation mode detection device is provided, including at least one processor, a receiver, and a memory, wherein the at least one processor is configured to read a program in the memory and execute the following process: for each Candidate modulation method: According to the channel matrix, the receiver signal vector received by the receiver is jointly detected to obtain the cumulative branch metric vector corresponding to each RE; and the minimum value of the cumulative branch metric vector corresponding to each RE is summed up. Operation to obtain the minimum cumulative branch metric value corresponding to the candidate modulation method; determine the minimum value from the minimum cumulative branch metric value corresponding to each candidate modulation method, and determine the modulation method corresponding to the determined minimum value as used by the interfering cell Modulation mode; the receiver is configured to receive data under the control of the at least one processor.

In a possible implementation manner, the at least one processor is configured to read a program in the memory and execute the following process: for each candidate modulation mode, perform a tree search on the signals transmitted by each layer of the serving cell according to the channel matrix, A branch metric vector corresponding to each RE in the serving cell is obtained; according to the obtained branch metric vector, for each candidate modulation method, a tree search is performed on signals transmitted at each layer of the interfering cell to obtain a cumulative branch metric corresponding to each RE. Value vector; where the tree search represents the process of selecting the smallest M reserved branches layer by layer, which represents the combination of candidate constellation symbols corresponding to each layer of the serving cell and each layer of the interfering cell.

In a possible implementation manner, if there are at least two interfering cells, the at least one processor is configured to read a program in the memory and execute the following process: according to the obtained branch metric vector, for each candidate modulation mode, According to the signal receiving power of each interfering cell in descending order, a tree search is performed on the signals transmitted at each layer of each interfering cell in order to obtain a cumulative branch metric vector corresponding to each RE.

In a possible implementation manner, the at least one processor is further configured to read a program in the memory and execute the following process: for each candidate modulation mode, according to a channel matrix, joint detection is performed on a received signal vector to obtain each RE Corresponding reserved branch, wherein each RE corresponds to the reserved branch corresponding to the cumulative branch metric vector corresponding to the RE; the soft bit is calculated according to the modulation method used by the interfering cell and the reserved branch corresponding to the determined minimum value And output.

In a possible implementation manner, the candidate modulation modes include: QPSK and 64QAM.

In the method and device provided by the embodiments of the present invention, during the joint detection, all candidate modulation modes are input to determine the modulation mode used by the interfering cell. Since the blind detection of the modulation mode is not required during the blind parameter detection, the blind modulation mode is avoided. The repeated calculations between inspection and joint detection reduce the processing complexity of the receiver and make it easy to achieve commercialization.

S31-S32‧‧‧step

51‧‧‧Minimum cumulative branch metric determination module

52‧‧‧Modulation mode determination module

600‧‧‧ processor

610‧‧‧ Receiver

620‧‧‧Memory

1 is a schematic diagram of a model of a NAICS receiver in the related art; FIG. 2 is a schematic diagram of a model of a NAICS receiver provided by an embodiment of the present invention; FIG. 3 is a schematic diagram of a modulation method detection method provided by an embodiment of the present invention; A schematic diagram of a tree search provided by an embodiment of the present invention; FIG. 5 is a schematic diagram of a modulation mode detection device provided by an embodiment of the present invention; and FIG. 6 is a schematic diagram of another modulation mode detection device provided by an embodiment of the present invention.

In order to make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of the embodiments of the present invention, but not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without making creative work fall into the protection scope of the present invention.

The model of the NAICS receiver provided by the embodiment of the present invention is shown in FIG. 2 and includes a channel estimation module, a blind detection module, and a joint detection module. Among the blind detection modules, only PDSCH interference exists and interference transmission The parameters such as mode, codebook, and layer number are blindly detected. The modulation method of the interfering cell is not blindly detected. In the joint detection module, all possible modulation methods (ie, candidate modulation methods) of the interfering cell are input, and the joint detection is performed separately. Thus, the modulation mode used by the interfering cell is determined, and the soft bit is calculated and output according to the cumulative branch metric vector and the reserved branch corresponding to the modulation mode used by the interfering cell, thereby completing the receiver function.

The embodiments of the present invention are described in further detail below with reference to the accompanying drawings. It should be understood that the embodiments described herein are only used to illustrate and explain the present invention, and are not intended to limit the present invention.

In the embodiment shown in FIG. 3, a modulation method detection method is provided. The method includes:

S31. For each candidate modulation method, according to the channel matrix, joint detection is performed on the received signal vector to obtain the cumulative branch metric vector corresponding to each RE; and the minimum value in the cumulative branch metric vector corresponding to each RE is summed up. To obtain the minimum cumulative branch metric value corresponding to the candidate modulation mode.

In a possible implementation manner, when performing joint detection, a Reduced-Maximum Likelihood (R-ML) detection algorithm may be used, such as QR-Decomposition-based M (QRD- M) Detection algorithm.

Among them, the basic idea of the QRD-M detection algorithm is: traverse the search tree (also known as the signal tree) layer by layer, and select the M branches that are most likely to be correct at present (that is, the most likely constellations in each layer of the serving cell and each layer in the interference cell). Combination of symbols), the selection is based on the selection of the branch with a smaller cumulative metric value, and after all layers are searched, the cumulative branch metric vector BM (1 × M dimension) and the corresponding reserved branch X _left ( N _L × M dimension), N _L represents the number of layers of the search tree. The number of layers in the search tree represents the number of symbols sent on the same time-frequency resource, and the value is the sum of the number of layers in the serving cell and the number of layers in the interfering cell, where M is a preset value. The branches of the search tree represent combinations of candidate constellation symbols corresponding to each layer of the serving cell and each layer of the interfering cell. The candidate constellation symbols are all possible constellation symbols in a modulation mode.

S32. Determine a minimum value from a minimum cumulative branch metric value corresponding to each candidate modulation method, and determine a modulation method corresponding to the determined minimum value as a modulation method used by the interfering cell.

In the embodiment of the present invention, during the joint detection, all candidate modulation modes are input to determine the modulation mode used by the interfering cell. Since the blind detection of the modulation mode is not required during the blind parameter inspection, the blind detection of the modulation mode and the joint detection are avoided The repeated calculations between them reduce the processing complexity of the receiver and make it easy to achieve commercialization.

In a possible implementation manner, for each candidate modulation method in S31, the received signal vectors are jointly detected according to the channel matrix to obtain a cumulative branch metric vector corresponding to each RE, including: first, according to the channel matrix, A tree search is performed on the signals transmitted at each layer to obtain the branch metric vector corresponding to each RE in the serving cell; and according to the obtained branch metric vector, for each candidate modulation method, a tree is formed for the signal transmitted at each layer of the interfering cell. Search to get the cumulative branch metric vector corresponding to each RE. The tree search indicates a process of selecting the smallest M reserved branches layer by layer, and the branch represents a combination of candidate constellation symbols corresponding to each layer of the serving cell and each layer of the interfering cell.

The above tree search process is shown in FIG. 4. Starting from the root node, the search is performed layer by layer, that is, the tree search is performed from layer N _L (Layer N _L ) to layer 1, in which layer N _L and layer N _{L -1} For the layers of the serving cell, layer 1 is the layer for the interfering cell.

In the joint detection process, the detection performance of the first searched layer has the most important impact on the overall performance. Since the modulation method of the serving cell is known, the tree search is performed on the signals transmitted by the layers of the serving cell. Does not affect overall performance.

In a possible implementation manner, if there are at least two interfering cells, according to the obtained branch metric vector, for each candidate modulation method, a tree search is performed on the signals transmitted at each layer of the interfering cell to obtain the accumulation corresponding to each RE. The branch metric vector includes: according to the obtained branch metric vector, for each candidate modulation mode, the signals transmitted at each layer of each interfering cell are sequentially processed in accordance with the signal receiving power of each interfering cell in order from large to small. Tree search to get the cumulative branch metric vector corresponding to each RE.

In the joint detection process, the detection performance of the layer that is searched first has the most important impact on the overall performance. A tree search of the signals transmitted by the layers of the interfering cell with high signal reception power can reduce the impact on the overall performance. .

Based on any of the above embodiments, for each candidate modulation method in S31, the received signal vector is jointly detected according to the channel matrix to obtain a cumulative branch metric vector corresponding to each RE, and further includes: for each candidate modulation method, according to The channel matrix performs joint detection on the received signal vector to obtain the reserved branches corresponding to each RE. Among them, the reserved branch corresponding to each RE corresponds to the cumulative branch metric vector corresponding to the RE one by one. Correspondingly, after S32, it also includes : Calculate and output soft bits according to the modulation method used by the interfering cell and the reserved branch corresponding to the determined minimum value, thereby completing the receiver function.

In the embodiment of the present invention, the candidate modulation modes include, but are not limited to, QPSK, 16QAM, and 64QAM.

In the joint detection, since the modulation mode of the interfering cell is 16QAM, and the actual detection is incorrectly determined to be 64QAM, there will be no significant performance loss. An optimization solution is to traverse only QPSK and 64QAM modulation modes during joint detection, that is, to optimize the candidate modulation mode to include only QPSK and 64QAM.

Based on any of the above embodiments, assuming that there are two interfering cells, the combination of the three candidate modulation modes is 9, namely {QPSK, QPSK}, {QPSK, 16QAM}, {QPSK, 64QAM}, {16QAM, 16QAM}, { 16QAM, QPSK}, {16QAM, 64QAM}, {64QAM, QPSK}, {64QAM, 16QAM}, {64QAM, 64QAM}, traverse the combination of all the above modulation methods, and determine the smallest branch metric value corresponding to the modulation method The combination is the modulation method of the two interfering cells.

The following uses the QRD-M detection algorithm as an example to describe the function of a receiver implemented based on a modulation method detection method provided by an embodiment of the present invention.

Step 0: Sort the channel matrix H _cmb so that the columns of the serving cell are on the right side of the matrix and the columns of the interfering cell are on the left side of the matrix. If the serving cell has multiple layers, the signal receiving power in the corresponding columns of the serving cell is relatively The large column is located on the right side of the matrix. Similarly, if the interfering cell has multiple layers, the column with the higher power among the columns corresponding to the interfering cell is located on the relatively right side. The reordered matrix is .

_{Wherein, H cmb = (H S,} eq H, eq) represents the H _{S, eq} and H _{I, eq} combined virtual multiple input multiple output transmission channel (Multiple-Input Multiple-Output, MIMO) system, dimension N _R × N _L , H _{S , eq} represents an equivalent channel estimate between the serving cell and the UE, H _{I , eq} represents an equivalent channel estimate between the interfering cell and the UE, and N _R represents the number of receiving antennas.

N _L = N _S + N _I , N _S represents the number of layers of the serving cell, and N _I represents the number of layers of the interfering cell.

Step 1: Pair the channel matrix QR decomposition is performed, where the Q matrix is a unitary matrix and the R matrix is an upper triangular matrix. Initialize X _{left , l} is an empty matrix of N _L × M , BM _l is a vector of 1 × M , l {1, ... L } represents the lth RE.

Step 2: Multiply the received signal vector r by Q ^H to get the equivalent received vector. . Among them, r represents an N _R × 1-dimensional received signal vector, and N _R represents the number of receiving antennas.

Step 3: On the l th REs, the signal transmitted N _L layers from the first layer to the N _L N _L - N _S +1 layers (layers serving cell) layer by layer search tree, initialization X _{left, l} Is the N _L × M all-zeros matrix.

One possible embodiment, a calculation using a formula increment branch metrics (Branch Metric) layer of the current search for the layer (i.e., the first layer serving cell search) searches a first calculation times required Q _s, Q _s is the number of constellation points in the currently input candidate modulation mode, that is, Q _s constellation points are brought into formula one for calculation: among them, Representation vector The N _Lth element in s _q (1 q Q _s ) represents the signal hypothesis transmitted by the current search layer, ( q ) represents the metric value corresponding to the q th constellation point of the N _L layer calculated according to Formula One; through the above calculation, a total of Q _s ( q ), choose the smallest M ( M Q _s ) metric values are stored in BM _l , and s _q corresponding to the selected M metric values is written into the N _Lth row of X _{left , l} , and the remaining branches are discarded.

If the number of layers of the serving cell is greater than one layer, then each layer (ie, layers N _L -1 to N _L - N _S +1) performs the calculation of the branch metric value increment of M × Q _s according to formula 2: Where i { N _L -1,…, N _L - N _S +1}, m {1, ..., M }.

For the i { N _L -1,…, N _L - N _S +1} layer searched signal, according to formula three, calculate the cumulative branch metric value: BM _tmp (( m -1) × Q _s + q ) = BM _l ( m ) + bm _i (( m -1) × Q _s + q ) Formula three; keep the smallest M values of BM _tmp among the M × Q _s cumulative branch metric values and store them in BM _l The subscripts of the smallest M values are z ₁ , z ₂ , ... z _M. According to Equation 4, replace the elements in line i + 1 to line N _L in X _{left , l} . Let For N _L × M all-zero matrix: Among them, the corresponding s _{q is} written into the ith row of X _{left , l} , and the remaining branches are discarded.

Step 4: On the lth RE, a layer-by-layer tree search is performed on the signal transmitted by the N _L layer from the N _L - N _S layer to the first layer (that is, each layer of the interfering cell) and initialized. For X _{left , l} , K {4,16,64} respectively indicate the branches corresponding to the three modulation modes and the initialization Is BM _l , K {4,16,64} represents the cumulative branch metric values of the branches corresponding to the three modulation modes respectively; for each layer of the interfering cell ( i { N _L - N _S ,…, 1}) According to formula 5, perform M × K branch metric value increment operation: Where s _q (1 q K), corresponding to a signal indicating the current search layer constellation symbols transmitted hypothesis; for the i { N _L - N _S ,…, 1} layer searched signals, according to formula 6, calculate the cumulative branch metric value: Keep the smallest M values in BM _tmp among the M × K cumulative branch metrics Suppose that the subscripts of the smallest M values in ascending order are z ₁ , z ₂ , ... z _M , and replace them according to the following formula 7. I-th element of the N _L + 1 rows, so For N _L × M all-zero matrix: Corresponding s _q write Line i , the remaining branches are discarded; the output after the search at layer 1 is completed Contains M branches, Is the corresponding cumulative branch metric.

The process of step 4 is performed for all K hypotheses.

Step 5: On L REs Sum the first value in (that is, the smallest cumulative branch metric), that is, ; Then, determine the modulation method corresponding to the smallest value in metric _m , that is, .

Step 6: Based on the modulation method determined in step 5 with Calculate the soft bits according to Equation 8, and output: among them The modulation method is When the corresponding modulation scheme for the l th branch left RE of the first layer q n _l a branch bit set to 0, It represents a left branch of the first layer n _l q bits set to branch 1, n _l {1,…, N _S }, q {1, ..., Q _s }, where Q _s represents the modulation order.

The following describes in detail a modulation method detection method provided by an embodiment of the present invention through two specific embodiments.

Embodiment 1: In this embodiment, it is assumed that in the LTE-A system, the system bandwidth is 10 MHz, and the serving cell is a layer 1 closed-loop transmission of Transmission Mode 4 (TM4). The occupied physical resource block (Physical Resource Block) BLock (PRB) is PRB0-PRB4; the interfering cell is also a layer 1 closed-loop transmission of TM4, and the occupied PRB is PRB0-PRB4. The receiver accurately completes the channel estimation of the serving cell and the interfering cell, and accurately completes the blind detection of parameters such as the existence of interference, transmission mode, codebook, and number of layers of interference on each PRB, and outputs it to the detection module. . In this embodiment, the detection module is a QRD-M detector as an example. The QRD-M detector performs the following process: firstly performs a tree search of the serving cell 1 layer, and then based on the assumption of different modulation modes of the interfering cell { QPSK, 16QAM, 64QAM} to perform a tree-level search of the interfering cell and output the cumulative branch metric vector BM _{l , m} and the reserved branch X _{left , l , m} corresponding to each modulation scheme assumption on each RE; After completing the tree search under each modulation scheme hypothesis of all REs on 5 PRBs, sum the smallest cumulative branch metric values corresponding to all REs under each modulation scheme hypothesis to calculate the metric corresponding to each modulation scheme Value metric _m to find the smallest metric value To determine the corresponding modulation method; finally, based on the determined modulation method, with Calculate the soft bits and output.

This embodiment is also applicable to a case where the transmission mode and / or the number of layers of the serving cell are different from the transmission mode and / or the number of layers of the interfering cell. The specific process is similar, and no further examples are given here.

Embodiment 2: In this embodiment, it is assumed that in the LTE-A system, the system bandwidth is 10 MHz, the serving cell is TM3 open-loop layer 2 spatial multiplexing transmission, and the occupied PRB is PRB0-PRB4; the interfering cell is also TM3 open-loop. Layer 2 spatial multiplexing transmission, the PRB occupied is PRB0-PRB4. The receiver accurately completes the channel estimation of the serving cell and the interfering cell, and accurately completes the blind detection of parameters such as the presence of interference, transmission mode, and number of layers of interference on each PRB, and outputs it to the detection module. In this embodiment, the detection module is a QRD-M detector as an example. The QRD-M detector performs the following process: first performs a tree search at the serving cell layer 2, and then uses two different modulation methods based on the interfering cell. Assume {QPSK, 64QAM}, perform a tree search at layer 2 of the interfering cell, and output the cumulative branch metric vectors BM _{l , m} and reserved branches X _{left , l , m} corresponding to each RE under the assumption of two modulation modes; After completing the tree search under the assumptions of the two modulation modes of all REs on the five PRBs, the minimum cumulative branch metric values corresponding to all REs under the two modulation modes are summed to calculate the metric corresponding to the two modulation modes. Value metric _m to find smaller metric values To determine the corresponding modulation method; finally, based on the determined modulation method, with Calculate the soft bits and output.

This embodiment is also applicable to a case where the transmission mode and / or the number of layers of the serving cell are different from the transmission mode and / or the number of layers of the interfering cell. The specific process is similar, and no further examples are given here.

It should be noted that the QRD-M algorithm is used as an example in the embodiments of the present invention, but the embodiments of the present invention are not limited to the QRD-M algorithm. Other R-ML algorithms are also applicable. Similarly, no further examples are given here.

The above method processing flow can be implemented by a software program, which can be stored in a storage medium, and when the stored software program is called, the above method steps are executed.

Based on the same inventive concept, an embodiment of the present invention further provides a modulation mode detection device. Since the principle of solving the problem of the device is similar to the method in the embodiment shown in FIG. 3 described above, the implementation of the device can refer to the method implementation. Duplicates are not repeated here.

In the embodiment shown in FIG. 5, a modulation mode detection device is provided. The device includes a minimum cumulative branch metric determination module 51 for jointly detecting a received signal vector according to a channel matrix for each candidate modulation mode. To obtain the cumulative branch metric vector corresponding to each RE; sum the minimum values in the cumulative branch metric vector corresponding to each RE to obtain the minimum cumulative branch metric value corresponding to the candidate modulation method; modulation mode determination module 52 , Used to determine the minimum value from the minimum cumulative branch metric value corresponding to each candidate modulation method, and determine the modulation method corresponding to the determined minimum value as the modulation method used by the interfering cell.

In a possible implementation manner, the minimum cumulative branch metric determination module 51 is specifically configured to: for each candidate modulation method, first perform a tree search on the signals transmitted at each layer of the serving cell according to the channel matrix, and obtain A branch metric vector corresponding to each RE; and according to the obtained branch metric vector, for each candidate modulation mode, a tree search is performed on signals transmitted at each layer of the interfering cell to obtain a cumulative branch metric vector corresponding to each RE; The tree search represents a process of selecting the smallest M reserved branches layer by layer, and the branch represents a combination of candidate constellation symbols corresponding to each layer of the serving cell and each layer of the interfering cell.

In a possible implementation manner, if there are at least two interfering cells, the minimum cumulative branch metric determination module 51 is specifically configured to: according to the obtained branch metric vector, for each candidate modulation method, according to the interference cell's In order of the received signal power, the tree-shaped search is performed on the signals transmitted at each layer of each interfering cell in order, to obtain the cumulative branch metric vector corresponding to each RE.

In a possible implementation manner, the minimum cumulative branch metric determination module 51 is further configured to: for each candidate modulation method, perform joint detection on the received signal vector according to the channel matrix to obtain a reserved branch corresponding to each RE, where: The reserved branch corresponding to each RE corresponds to the cumulative branch metric vector corresponding to the RE one by one; the modulation method determining module 52 is further configured to: according to the modulation method used by the interfering cell and the reserved branch corresponding to the determined minimum value , Calculates the soft bits and outputs.

In a possible implementation manner, the candidate modulation modes include: QPSK and 64QAM.

In the embodiment shown in FIG. 6, another modulation mode detection device is provided, including at least one processor 600, a receiver 610, and a memory 620, where the at least one processor 600 is configured to read the information in the memory 620. The program executes the following process: for each candidate modulation method, according to the channel matrix, the received signal vector received by the receiver 610 is jointly detected to obtain the cumulative branch metric vector corresponding to each RE; and the cumulative branch metric corresponding to each RE The minimum value in the value vector is summed to obtain the minimum cumulative branch metric value corresponding to the candidate modulation mode; the minimum value is determined from the minimum cumulative branch metric value corresponding to each candidate modulation mode, and the determined minimum value is corresponding to The modulation mode is determined as the modulation mode used by the interfering cell; the receiver 610 is configured to receive data under the control of the at least one processor 600.

In FIG. 6, the bus architecture may include any number of interconnected buses and bridges. Specifically, one or more processors represented by the processor 600 and various circuits of the memory represented by the memory 620 are connected together. The bus architecture can also link various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art, and therefore, they will not be further described herein. The bus interface provides an interface. The receiver 610 provides a unit for communicating with various other devices on a transmission medium. The processor 600 is responsible for managing the bus architecture and general processing, and can also provide various functions, including timing, peripheral interfaces, voltage regulation, power management, and other control functions. The memory 620 may store data used by the processor 600 when performing operations.

In a possible implementation manner, the processor 600 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), and a field-programmable gate array (FPGA). ) Or Complex Programmable Logic Device (CPLD).

In a possible implementation manner, the at least one processor 600 reads a program in the memory 620 and executes the method in the embodiment shown in FIG. 3.

In the embodiment of the present invention, the device shown in FIG. 5 and FIG. 6 may be set in a terminal; it may also be set in a network device, such as a base station.

Those skilled in the art should understand that the embodiments of the present invention may be provided as a method, a system, or a computer program product. Therefore, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk memory, CD-ROM, optical memory, etc.) containing computer-usable code therein. .

The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, and a combination of the process and / or block in the flowchart and / or block diagram may be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing device to generate a machine for instructions executed by the processor of the computer or other programmable data processing device Means are generated for implementing the functions specified in one or more of the flowcharts and / or one or more of the block diagrams.

These computer program instructions can also be stored in computer readable memory that can guide a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce a manufactured article including a command device The instruction device implements the functions specified in a flowchart or a plurality of processes and / or a block or a plurality of blocks in the block diagram.

These computer program instructions can also be loaded on a computer or other programmable data processing equipment, so that a series of operating steps can be performed on the computer or other programmable equipment to generate computer-implemented processing, and thus on the computer or other programmable equipment The instructions executed on the steps provide steps for implementing the functions specified in one or more of the flowcharts and / or one or more of the block diagrams.

Although the preferred embodiments of the present invention have been described, those skilled in the art can make other changes and modifications to these embodiments once they know the basic inventive concepts. Therefore, the scope of the appended patent applications is intended to be construed to include the preferred embodiments and all changes and modifications that fall within the scope of the invention.

Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. In this way, if these modifications and variations of the present invention fall within the scope of the patent application for the present invention and the scope of the equivalent technology, the present invention also intends to include these modifications and variations.

Claims (14)

    A modulation method detection method, characterized in that the method includes: for each candidate modulation method, joint detection of a received signal vector according to a channel matrix to obtain a cumulative branch metric vector corresponding to each resource unit RE; and corresponding each RE Sum the minimum values in the cumulative branch metric vector to obtain the minimum cumulative branch metric value corresponding to the candidate modulation mode; determine the minimum value from the minimum cumulative branch metric value corresponding to each candidate modulation mode, and determine the minimum The modulation method corresponding to the minimum value is determined as the modulation method used by the interfering cell.         The modulation method detection method according to claim 1, wherein, for each candidate modulation method, the received signal vector is jointly detected according to the channel matrix to obtain a cumulative branch metric vector corresponding to each RE, including: according to the channel matrix, Perform tree search on the signals transmitted at each layer of the serving cell to obtain the branch metric vector corresponding to each RE in the serving cell; according to the obtained branch metric vector, for each candidate modulation method, the signals transmitted at each layer of the interfering cell A tree search is performed to obtain the cumulative branch metric vector corresponding to each RE; where the tree search represents the process of selecting the smallest M reserved branches layer by layer, and this branch represents the candidate constellation symbols corresponding to each layer of the serving cell and each layer of the interfering cell The combination.         The modulation method detection method according to claim 2, wherein, according to the obtained branch metric value vector, for each candidate modulation method, a tree search is performed on signals transmitted at each layer of the interfering cell to obtain a cumulative branch corresponding to each RE. A metric value vector includes: if there are at least two interfering cells, according to the obtained branch metric value vector, for each candidate modulation mode, in accordance with the signal receiving power of each interfering cell in order from large to small, for each candidate A tree search is performed on the signals transmitted by the layers of the interfering cell to obtain a cumulative branch metric vector corresponding to each RE.         The modulation method detection method according to claim 1, further comprising: for each candidate modulation method, performing joint detection on the received signal vector according to the channel matrix to obtain a reserved branch corresponding to each RE, where each RE corresponds to The reserved branches correspond to the cumulative branch metric vector corresponding to the RE one by one; after determining the modulation method corresponding to the determined minimum value as the modulation method used by the interfering cell, the method further includes: The reserved branch corresponding to the determined minimum value, the soft bits are calculated and output.         The modulation method detection method according to claim 1, wherein the candidate modulation methods include: quadrature phase shift keying QPSK and 64 quadrature amplitude modulation QAM.         A modulation mode detection device, characterized in that the device includes: a minimum cumulative branch metric determination module, which is used to jointly detect a received signal vector according to a channel matrix for each candidate modulation mode, and obtain a corresponding RE of each resource unit. Cumulative branch metric vector; sum the minimum value of the cumulative branch metric vector corresponding to each RE to get the minimum cumulative branch metric value corresponding to the candidate modulation method; the modulation mode determination module is used to A minimum value is determined from a minimum cumulative branch metric value corresponding to the candidate modulation method, and a modulation method corresponding to the determined minimum value is determined as a modulation method used by the interfering cell.         The modulation method detection device according to claim 6, wherein the minimum cumulative branch metric determination module is specifically configured to: for each candidate modulation method, perform a tree search on the signals transmitted by each layer of the serving cell according to the channel matrix To obtain the branch metric vector corresponding to each RE in the serving cell; according to the obtained branch metric vector, for each candidate modulation method, perform a tree search on the signals transmitted at each layer of the interfering cell to obtain the cumulative branch corresponding to each RE Metric vector; where the tree search represents the process of selecting the smallest M reserved branches layer by layer, and the branch represents the combination of candidate constellation symbols corresponding to each layer of the serving cell and each layer of the interfering cell.         The modulation mode detection device according to claim 6, wherein the minimum cumulative branch metric determination module is further configured to: for each candidate modulation mode, perform joint detection on the received signal vector according to the channel matrix to obtain correspondences of each RE The reserved branch corresponding to each RE corresponds to the cumulative branch metric vector corresponding to the RE one-to-one; the modulation mode determination module is further configured to determine the modulation mode corresponding to the determined minimum value as interference After the modulation method used by the cell, the soft bits are calculated and output according to the modulation method used by the interfering cell and the reserved branch corresponding to the determined minimum value.         A modulation mode detection device, comprising: at least one processor, a receiver, and a memory; the at least one processor is configured to read a program in the memory and execute the following process: for each candidate modulation mode , According to the channel matrix, jointly detect the received signal vector received by the receiver to obtain a cumulative branch metric vector corresponding to each resource unit RE; and perform a sum operation on the minimum value of the cumulative branch metric vector corresponding to each RE To obtain the minimum cumulative branch metric value corresponding to the candidate modulation method; determine the minimum value from the minimum cumulative branch metric value corresponding to each candidate modulation method, and determine the modulation method corresponding to the determined minimum value as the modulation used by the interfering cell Manner; the receiver is configured to receive data under the control of the at least one processor.         The modulation mode detection device according to claim 9, wherein the at least one processor is configured to read a program in the memory and execute the following process: for each candidate modulation mode, according to the channel matrix, the A tree search is performed on the signals transmitted at each layer to obtain the branch metric vector corresponding to each RE in the serving cell; according to the obtained branch metric vector, a tree search is performed for the signals transmitted at each layer of the interfering cell for each candidate modulation mode. To obtain a cumulative branch metric vector corresponding to each RE; wherein the tree search represents a process of selecting the smallest M reserved branches layer by layer, and the branch represents a combination of candidate constellation symbols corresponding to each layer of the serving cell and each layer of the interfering cell.         The modulation method detection device according to claim 10, wherein the at least one processor is configured to read a program in the memory and execute the following process: if there are at least two interference cells, according to the obtained branch metrics Value vector. For each candidate modulation method, according to the signal receiving power of each interfering cell in descending order, a tree search is performed on the signals transmitted at each layer of each interfering cell in order to obtain the cumulative branch metric value corresponding to each RE. vector.         The modulation mode detection device according to claim 9, wherein the at least one processor is further configured to read a program in the memory and execute the following process: For each candidate modulation mode, according to the channel matrix, the received signal is The joint detection of the vectors is performed to obtain the reserved branches corresponding to each RE, wherein the reserved branch corresponding to each RE corresponds to the cumulative branch metric vector corresponding to the RE one to one; the at least one processor is further configured to read the memory In the program in, the following process is performed: after the modulation method corresponding to the determined minimum value is determined as the modulation method used by the interfering cell, the soft bit is calculated according to the modulation method used by the interference cell and the reserved branch corresponding to the determined minimum value. And output.         The modulation method detection device according to any one of claims 9 to 12, wherein the candidate modulation methods include: quadrature phase shift keying QPSK and 64 quadrature amplitude modulation QAM.         A computer storage medium, characterized in that the computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to cause the computer to execute the method according to any one of claims 1 to 5.