Power line MIMO system receiving end filter coefficient generation method based on subcarrier design

Abstract

The invention provides a power line MIMO system receiving end filtering coefficient generation method. The accuracy of channel estimation is optimized based on subcarrier design. The method comprises the following steps: firstly, selecting a subcarrier index to represent the frequency domain response of a channel to be filtered, and then carrying out sub-band region division on the whole bandwidth to capture the difference and fading characteristics of the frequency domain channel. Then, time-domain characteristic parameters, such as a signal-to-noise ratio and a power delay spectrum, are calculated using the frequency-domain channel response. Finally, a filtering coefficient matrix is generated based on the time-domain characteristic parameters, so that the accuracy of channel estimation is improved. According to the method, differences of channels on different frequencies are considered, so that time domain characteristic parameter estimation is more accurate, a solid technical basis is provided for filter coefficient generation, and the performance of a whole communication system is improved.

Description

Technical Field

[0001] The present invention relates to the field of power line communication, and in particular to a method for generating filter coefficients at a receiving end in a power line multiple-input multiple-output (MIMO) system, and a method for designing frequency domain subcarriers corresponding to the time domain characteristic parameters of a channel estimated by using a frequency domain channel during the filter coefficient generation process. Background Art

[0002] When the communication system receiver performs channel estimation, it is generally necessary to use the minimum mean square error (MMSE) for filtering. MMSE filtering is an optimization calculation used for channel estimation in noisy conditions. It estimates the channel response by minimizing the error between the estimated channel and the actual channel. In the PLC communication system, if the channel conditions change rapidly, the use of MMSE filtering can accurately estimate the channel and reduce the bit error rate. At the same time, it can effectively resist multipath effects and frequency domain selective new fading, and improve the overall performance of the system.

[0003] The MMSE-based channel estimation is based on the least squares (LS) channel estimation. The LS-based channel estimation algorithm needs to be combined with the pilot signal. Without loss of generality, it is assumed that It means that the channel response H = [H1, H2, ..., H M ] is an estimated value, is the expected response value at pilot m. Then the channel estimation based on MMSE is expressed as follows

[0004]

[0005] The filter coefficient matrix W can be written as

[0006]

[0007] Among them, R HH is the autocorrelation matrix of the channel H. In the communication system, the application of MMSE filtering may be designed to the channel estimation, equalization and other modules. Therefore, it is necessary to calculate the MMSE filter coefficient according to the specific parameters and actual application scenario requirements to achieve the best effect.

[0008] For a MIMO PLC multipath channel system, calculate the autocorrelation coefficient matrix R HH It is necessary to know the actual channel response and signal-to-noise ratio, so the propagation characteristics of the multipath channel are needed to estimate the power delay, modulate the channel impulse response in the time domain, and obtain the noise power and effective path energy by analyzing the power attenuation at different times, and then convert them to the frequency domain to obtain the signal-to-noise ratio and autocorrelation coefficient matrix.

[0009] For a multipath channel system, the channel frequency domain channel response modeling at time t is as follows

[0010]

[0011] where τ l is the path l delay, a l (t) is the time domain channel coefficient at time t. Considering that different paths are independent of each other, the channel autocorrelation function is written as

[0012]

[0013] The frequency domain autocorrelation function can be further written as

[0014]

[0015] Where Gl = E(al 2 ) is the average channel gain, that is, the channel energy. It can be seen from formula (5) that the channel frequency domain autocorrelation function is the time domain channel energy, that is, the Fourier transform of the power delay spectrum.

[0016] It can be seen from formula (2) that the frequency domain filter coefficient matrix is ​​also affected by the signal-to-noise ratio.

[0017] To calculate the channel signal-to-noise ratio in the frequency domain in formula (2), we need to calculate the channel response The corresponding time domain channel power delay spectrum and other time domain characteristic parameters are used to estimate the noise power and calculate the signal-to-noise ratio in the time domain, and finally the frequency domain signal-to-noise ratio is obtained by converting the time-frequency domain relationship. Therefore, the estimation of time domain characteristic parameters is very important for the generation of the filter coefficient matrix.

[0018] In the MIMOPLC receiving module, MMSE filtering is widely used in channel estimation and equalization modules, and the generation of the filter coefficient matrix requires the estimation of time domain characteristic parameters. When generating traditional filter coefficients, the channel matrix corresponding to the entire bandwidth subcarrier is selected as the benchmark to calculate the time domain channel response, and then the time domain channel is used to estimate the time domain characteristic parameters. This method does not fully consider the differences in frequency domain channels in different subcarriers and the fading problem of the channel in the frequency domain.

[0019] It should be noted that the information disclosed in the above background technology section is only used for understanding the background of the present application, and therefore may include information that does not constitute prior art known to ordinary technicians in the field. Summary of the invention

[0020] The main purpose of the present invention is to overcome the defects existing in the above-mentioned background technology and provide a method for generating filter coefficients at the receiving end of a power line MIMO system based on subcarrier design.

[0021] To achieve the above object, the present invention adopts the following technical solutions:

[0022] A method for generating filter coefficients at a receiving end of a power line MIMO system based on subcarrier design comprises the following steps:

[0023] S1. Subcarrier index selection: Select a set of subcarrier indices to represent the frequency domain response of the channel to be filtered, each subcarrier index corresponds to a specific frequency point in the power line MIMO system;

[0024] S2. Subband region division: The entire bandwidth of the power line MIMO system is divided into multiple subbands, each of which contains a certain number of subcarriers to consider the differences and fading characteristics of the frequency domain channel on different subcarriers;

[0025] S3. Calculation of time domain characteristic parameters: For each subcarrier index selected in step S1, the corresponding frequency domain channel response is used to calculate the time domain characteristic parameters of the channel, including the signal-to-noise ratio and the power delay spectrum, so as to estimate the propagation characteristics of the channel in time; for each subband divided in step S2, based on the frequency channel response corresponding to all subcarrier indexes in the subband, the time domain channel response, as well as the signal-to-noise ratio and the power delay spectrum are further refined and calculated;

[0026] S4. Generation of filter coefficient matrix: Based on the time domain characteristic parameters calculated in step S3, a filter coefficient matrix is ​​generated for filtering the channel response at the receiving end.

[0027] Furthermore, in the process of generating the filter coefficient matrix, for the frequency domain channel response to be filtered, the subcarrier correspondence between the channel response after filtering is designed according to the MMSE filter order F:

[0028] For the filtered channel subcarrier index q, if Set the starting position f of the subcarrier of the channel to be filtered a =1, the corresponding subcarrier index to be filtered is m∈{1,2,...,F};

[0029] For the filtered channel subcarrier index q, if Set the starting position f of the channel to be filtered a Starting from 1 to M-F+1, the subcarrier index to be filtered is m∈{f a ,f a +1,...,f a +F-1};

[0030] For the filtered channel subcarrier index q, if Set the starting position f of the channel to be filtered a=M-F+1, at this time the subcarrier index to be filtered is m∈{M-F+1,...,M}.

[0031] Furthermore, for the time domain parameter estimation based on the subcarrier index to be filtered, when the subcarrier index q after filtering satisfies When the channel corresponding to the subcarrier index {1,2,...,F} in the matrix to be filtered is used Compute the time domain channel response use Estimate the signal-to-noise ratio and power delay profile and generate filter coefficients.

[0032] Furthermore, for the time domain parameter estimation based on the subcarrier index to be filtered, when the subcarrier index q after filtering satisfies When, channel The starting position f of the subcarrier to be filtered a Starting from 1 to M-F+1, we can use the index {f a ,f a +1,...,f a +F-1} corresponding frequency domain channel Compute the time domain channel response use Estimate the signal-to-noise ratio and power delay profile and generate the filter vector w (F2)+1 ,...,w M-(F2) .

[0033] Furthermore, for the time domain parameter estimation based on the subcarrier index to be filtered, when the subcarrier index q after filtering satisfies When using the frequency domain channel corresponding to the subcarrier index {M-F+1,...,M} Compute the time domain channel response use Estimate the signal-to-noise ratio and power delay profile and generate the filter vector w M-(F2) +1,...,w M .

[0034] Furthermore, for subcarrier design based on subband area division for time domain parameter estimation, the entire bandwidth is divided into J subbands with subcarriers, and the number of subcarriers in each subband is M. j ,j=1,2,...,J, where the subband where the subcarrier of the filtered channel is located is taken as the reference and the subband set where the subcarrier of the channel to be filtered is located is taken as the reference.

[0035] Furthermore, for the estimation of the time domain characteristic parameters based on the subband where the subcarrier of the filtered channel is located, if the filtered channel response The subcarrier index q is located in subband j, then all subcarrier indexes in subband j are used The corresponding channel frequency response Compute the time domain channel response use Estimate the signal-to-noise ratio and power delay spectrum and generate the filter coefficient vector w q .

[0036] Furthermore, for the channel response to be filtered The sub-band where the sub-carrier index m is located is used as the reference for calculating the time domain characteristic parameters, and the time domain characteristic parameters are determined from f a to f a +F-1 all sub-bands where all sub-carriers are located, and all sub-bands are obtained. of Subbands. Using all subcarrier indices in the subband set The corresponding frequency domain channel response Compute the time domain channel response use Estimate the signal-to-noise ratio and power delay spectrum and generate the filter coefficient vector w q .

[0037] A computer-readable storage medium stores a computer program, wherein when the computer program is executed by a processor, the method for generating filter coefficients at a receiving end of a power line MIMO system based on subcarrier design is implemented.

[0038] A computer program product comprises a computer program, wherein when the computer program is executed by a processor, the method for generating filter coefficients at a receiving end of a power line MIMO system based on subcarrier design is implemented.

[0039] The present invention has the following beneficial effects:

[0040] The present invention proposes a method for generating filter coefficients at the receiving end of a power line MIMO system based on subcarrier design, which includes a design method for frequency domain subcarriers when generating filter coefficients. The frequency domain channels corresponding to the subcarriers used to calculate time domain characteristic parameters can be more flexibly selected, and the differences in channels at different frequencies are taken into account, so that the time domain characteristic parameter estimation is more accurate, so as to better lay a technical foundation for subsequent filter coefficient generation, improve the accuracy of channel estimation, and thus improve the performance of the entire system.

[0041] Other beneficial effects of the embodiments of the present invention will be further described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a method flow for designing channel time domain characteristic parameter estimation based on the subcarrier index to be filtered in an embodiment of the present invention.

[0043] Figure 2The invention discloses a design method flow for estimating channel time domain characteristic parameters based on the sub-band where the sub-carrier of the filtered channel response is located.

[0044] Figure 3 The invention discloses a design method flow for estimating channel time domain characteristic parameters based on a subband where a subcarrier of a channel response to be filtered is located.

[0045] Figure 4 It is a subcarrier mapping relationship diagram before and after filtering under the condition that the subcarrier to be filtered is used as the reference in an embodiment of the present invention.

[0046] Figure 5 It is a subcarrier mapping relationship diagram before and after filtering under the condition that the subband where the subcarrier after filtering is located is used as a reference in an embodiment of the present invention.

[0047] Figure 6 It is a subcarrier mapping relationship diagram before and after filtering under the condition that the subband where the subcarrier to be filtered is located is used as a reference in an embodiment of the present invention. DETAILED DESCRIPTION

[0048] The following is a detailed description of the embodiments of the present invention. It should be emphasized that the following description is only exemplary and is not intended to limit the scope and application of the present invention.

[0049] The present invention proposes a method for generating filter coefficients at the receiving end of a power line MIMO system based on subcarrier design, including a design method for frequency domain subcarriers corresponding to the time domain characteristic parameters of a channel estimated using a frequency domain channel when generating filter coefficients at the receiving end of the power line MIMO system. The method flow steps include: taking the subcarrier of the channel to be filtered as a reference and taking the subband area division as a reference, calculating the time domain channel response using the frequency domain channel corresponding to the designed subcarrier, and estimating the time domain characteristic parameters such as the signal-to-noise ratio and the power delay spectrum using the time domain channel response, and further generating a filter coefficient matrix.

[0050] The embodiment of the present invention provides a method for generating filter coefficients at a receiving end of a power line MIMO system based on subcarrier design, comprising the following steps:

[0051] S1. Subcarrier index selection: Select a set of subcarrier indices to represent the frequency domain response of the channel to be filtered, each subcarrier index corresponds to a specific frequency point in the power line MIMO system;

[0052] S2. Subband region division: The entire bandwidth of the power line MIMO system is divided into multiple subbands, each of which contains a certain number of subcarriers to consider the differences and fading characteristics of the frequency domain channel on different subcarriers;

[0053] S3. Calculation of time domain characteristic parameters: For each subcarrier index selected in step S1, the corresponding frequency domain channel response is used to calculate the time domain characteristic parameters of the channel, including the signal-to-noise ratio and the power delay spectrum, so as to estimate the propagation characteristics of the channel in time; for each subband divided in step S2, based on the frequency channel response corresponding to all subcarrier indexes in the subband, the time domain channel response, as well as the signal-to-noise ratio and the power delay spectrum are further refined and calculated;

[0054] S4. Generation of filter coefficient matrix: Based on the time domain characteristic parameters calculated in step S3, a filter coefficient matrix is ​​generated for filtering the channel response at the receiving end.

[0055] The embodiment of the present invention proposes a method for generating filter coefficients at the receiving end of a power line MIMO system based on subcarrier design, including a frequency domain subcarrier design method for generating filter coefficients at the receiving end. The design method includes: calculating channel time domain characteristic parameters based on the subcarrier index to be filtered and calculating time domain parameters based on the subband area division. For the design method for calculating channel time domain characteristic parameters based on the subcarrier index to be filtered: the receiving end estimates the channel time domain characteristic parameters based on the filter order and the frequency domain channel response corresponding to the subcarrier index; for the design method for estimating channel time domain characteristic parameters based on the subband area division, firstly, all subcarriers are divided into several subbands, including two schemes, one is to estimate the channel time domain characteristic parameters based on the subband where the subcarrier of the filtered channel is located, and the other is to estimate the channel time domain characteristic parameters based on the subband set where the subcarrier of the channel to be filtered is located.

[0056] The present invention provides a design method for estimating channel time domain characteristic parameters in a power line MIMO transmission system. Assuming that the receiving port r and the transmitting port p have a channel frequency domain response of pilot subcarrier m and symbol s: Its time domain channel response is

[0058] in is the actual time-domain channel response, is the noise vector, and N is the Fourier transform size. Afterwards, use Calculate channel estimation parameters such as channel signal-to-noise ratio, power delay spectrum, and delay spread. According to formula (5), the frequency domain autocorrelation matrix is ​​calculated by the power delay spectrum, and then the filter coefficient matrix is ​​calculated by formula (2) in conjunction with the signal-to-noise ratio. Specific methods for calculating channel estimation parameters such as channel signal-to-noise ratio, power delay spectrum and delay spread are specified.

[0059] As described above, without loss of generality, assuming that the number of frequency domain pilot subcarriers is M and the filter order is F, the present invention considers a design method for subcarriers used for time domain characteristic parameter estimation when generating filter coefficients.

[0060] make Assuming the receiving port r and the transmitting port p have frequency domain responses in the subcarrier q and symbol s channel, Define the filter coefficient matrix as

[0061]

[0062] Can get

[0063]

[0064] where f a Indicates channel The starting position of the subcarrier to be filtered in w qm is the filter coefficient. It can be seen that in order to obtain the channel response after filtering A total of M filtering operations need to be performed.

[0065] The specific process of the design method for calculating the time domain parameters based on the subcarrier index to be filtered is as follows:

[0066] for Set up the channel The starting position f of the subcarrier to be filtered a =1, the subcarrier index to be filtered is m∈{1,2,...,F}. According to formula (6), the subcarrier index {1,2,...,F} corresponds to Frequency Domain Channel Response Compute the time domain channel response use Estimated Channel The signal-to-noise ratio and power delay spectrum are generated and the filter vectors w1, w2, ... w (F2)-1 .

[0067] for Set up the channel The starting position f of the subcarrier to be filtered a Starting from 1 to M-F+1, the subcarrier index to be filtered is m∈{f a ,f a +1,...,f a +F-1}. According to formula (6), using the index {f a ,f a +1,...,f a +F-1} corresponding to the frequency domain channel response Compute the time domain channel response use Estimate the channel’s signal-to-noise ratio and power delay spectrum and generate the filter vector w F2 ,...,w M-(F2) .

[0068] for Set up the channel The starting position f of the subcarrier to be filtered a =M-F+1. The subcarrier index to be filtered is m∈{M-F+1,...,M}. According to equation (6), the frequency domain channel response corresponding to the index {M-F+1,...,M} is used Compute the time domain channel response use Estimate the channel’s signal-to-noise ratio and power delay spectrum and generate the filter vector w M-(F2)+1 ,...,w M .

[0069] The specific process of designing the time domain characteristic parameter calculation based on the sub-band area division is as follows:

[0070] In general, the entire bandwidth is divided into multiple subbands based on the statistical characteristics of the channel. Without loss of generality, assume that the number of subbands is J and the number of subcarriers in each subband is M j ,j=1,2,...,J, the subcarrier indexes of each subband are In the present invention, the following two design schemes are considered.

[0071] For the time domain parameter calculation based on the subband where the pilot subcarrier of the filtered channel response is located, if the filtered channel response The subcarrier index q is located at subband j. According to formula (6), using the subcarrier index The corresponding frequency domain channel response Compute the time domain channel response use Estimate the signal-to-noise ratio and power delay spectrum of the channel and generate the filter coefficient vector w q For any satisfying For subcarrier q, the obtained autocorrelation matrix is ​​the same.

[0072] For the channel response to be filtered The subband at the location of the subcarrier index m is used as the reference for calculating the time domain characteristic parameters. Since m∈{f a ,f a +1,...,f a +F-1}, the subcarrier index starts from f a to f a +F-1 may belong to different sub-bands. In this case, we need to judge from fa to f a +F-1 The subband positions of all subcarriers. Without loss of generality, assume that the subcarrier index {f a ,f a +1,...,f a +F-1} is located in the subband number They are According to formula (6), using the subcarrier index The corresponding frequency domain channel response Compute the time domain channel response use Estimate the channel’s signal-to-noise ratio and power delay spectrum and generate the filter vector w q .

[0073] Examples

[0074] Without loss of generality, it is assumed that the number of pilot subcarriers for each transmitting port is M=200 and the filtering order is F=12.

[0075] If the time domain parameter calculation is based on the subcarrier index to be filtered, the specific implementation example is as follows:

[0076] For subcarrier index q≤5, set the channel The starting position of the subcarrier to be filtered is 1. At this time, the subcarrier index to be filtered is {1, 2, ..., 12}. Using the frequency domain channel response According to equation (6), the time domain channel response is calculated use Calculate the signal-to-noise ratio and power delay spectrum and generate filter vectors w1, w2, ... w5.

[0077] For subcarrier index 6≤q≤194, set the channel The starting position f of the subcarrier to be filtered a Starting from 1 to 189, the subcarrier index to be filtered is m∈{f a ,f a +1,...,f a +F-1}. For example, when q=7, f a =2, m∈{2,3,...,13}, when q=8, f a =3, m∈{3,4,...,14}, and so on. Using the frequency domain channel response Compute the time domain channel response use Calculate the signal-to-noise ratio and power delay spectrum and generate the filter vector w6,...,w 194 .

[0078] For q>194, set the channel The starting position f of the subcarrier to be filtered a =189, the subcarrier index to be filtered is m∈{189,...,200}. According to equation (6), using the frequency domain channel response Compute the time domain channel response use Calculate the signal-to-noise ratio and power delay spectrum and generate the filter vector w 195 ,...,w 200 .

[0079] The specific implementation example of designing time domain parameter calculation based on sub-band area division is as follows:

[0080] In general, the entire bandwidth is divided into multiple subbands according to the statistical characteristics of the channel. Without loss of generality, assume that the number of subbands is J = 10 and the number of subcarriers in each subband is M. j =20, in the present invention, the following two design schemes are considered.

[0081] The subband where the subcarrier of the filtered channel response is located is used as the reference for time domain parameter calculation. If the filtered channel response The index q=23, then the position is subband j=2, According to equation (6), the frequency domain channel response corresponding to subband 2 is Compute the time domain channel response use Estimate the signal-to-noise ratio and power delay profile and generate the filter vector w 23 .

[0082] For the channel response used for filtering The position of the subcarrier index m is the time domain parameter calculation based on the subband. Similarly, if the channel response after filtering The index q = 23, then according to Subcarrier index based time domain parameter The number calculation method can get m∈{17,16,...,28}, that is, f a =17, The number of subbands where all subcarriers from 17 to 28 are located The subband set is Then the frequency domain channel response corresponding to subband 1 and subband 2 is used According to equation (6), the time domain channel response is calculated use Estimate the signal-to-noise ratio and power delay profile and generate the filter vector w 23 .

[0083] In summary, the present invention proposes a method for generating filter coefficients at the receiving end of a power line MIMO system, which optimizes the accuracy of channel estimation based on subcarrier design. The method first selects a key subcarrier index to represent the frequency domain response of the channel to be filtered, and then divides the entire bandwidth into subband regions to capture the differences and fading characteristics of the frequency domain channel. Next, the frequency domain channel response is used to calculate time domain characteristic parameters, such as signal-to-noise ratio and power delay spectrum. Finally, a filter coefficient matrix is ​​generated based on these time domain characteristic parameters to improve the accuracy of channel estimation. The method takes into account the differences in channels at different frequencies, making the estimation of time domain characteristic parameters more accurate, providing a solid technical foundation for the generation of filter coefficients, and thus improving the performance of the entire communication system.

[0084] An embodiment of the present invention further provides a storage medium for storing a computer program, which at least performs the above method when executed.

[0085] An embodiment of the present invention further provides a control device, comprising a processor and a storage medium for storing a computer program; wherein the processor is configured to execute at least the method described above when executing the computer program.

[0086] An embodiment of the present invention further provides a processor, wherein the processor executes a computer program and at least executes the method described above.

[0087] The storage medium can be implemented by any type of non-volatile storage device, or a combination thereof. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a magnetic random access memory (FRAM), a flash memory, a magnetic surface memory, an optical disc, or a compact disc read-only memory (CD-ROM); the magnetic surface memory can be a disk memory or a tape memory. The storage medium described in the embodiments of the present invention is intended to include, but is not limited to, these and any other suitable types of memory.

[0088] In the several embodiments provided by the present invention, it should be understood that the disclosed systems and methods can be implemented in other ways. The device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as: multiple units or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.

[0089] The units described above as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units; some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0090] In addition, all functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may be separately used as a unit, or two or more units may be integrated into one unit; the above-mentioned integrated units may be implemented in the form of hardware or in the form of hardware plus software functional units.

[0091] Those skilled in the art can understand that: all or part of the steps of implementing the above method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above method embodiments; and the aforementioned storage medium includes: mobile storage devices, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), disks or optical disks, etc. Various media that can store program codes.

[0092] Alternatively, if the above-mentioned integrated unit of the present invention is implemented in the form of a software function module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present invention can be essentially or partly reflected in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as mobile storage devices, ROM, RAM, magnetic disks or optical disks.

[0093] The methods disclosed in the several method embodiments provided by the present invention can be arbitrarily combined without conflict to obtain new method embodiments.

[0094] The features disclosed in several product embodiments provided by the present invention can be arbitrarily combined without conflict to obtain new product embodiments.

[0095] The features disclosed in several method or device embodiments provided by the present invention can be arbitrarily combined without conflict to obtain new method embodiments or device embodiments.

[0096] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art of the present invention, several equivalent substitutions or obvious variations can be made without departing from the concept of the present invention, and the performance or use is the same, which should be regarded as belonging to the protection scope of the present invention.

Claims

1. A method for generating filter coefficients at a receiving end of a power line MIMO system based on subcarrier design, characterized in that: The following steps are involved: S1. Subcarrier index selection: Select a set of subcarrier indices to represent the frequency domain response of the channel to be filtered, each subcarrier index corresponds to a specific frequency point in the power line MIMO system; S2. Subband region division: The entire bandwidth of the power line MIMO system is divided into multiple subbands, each of which contains a certain number of subcarriers to consider the differences and fading characteristics of the frequency domain channel on different subcarriers; S3. Calculation of time domain characteristic parameters: For each subcarrier index selected in step S1, the corresponding frequency domain channel response is used to calculate the time domain characteristic parameters of the channel, including the signal-to-noise ratio and the power delay spectrum, so as to estimate the propagation characteristics of the channel in time; for each subband divided in step S2, based on the frequency channel response corresponding to all subcarrier indexes in the subband, the time domain channel response, as well as the signal-to-noise ratio and the power delay spectrum are further refined and calculated; S4. Generation of filter coefficient matrix: Based on the time domain characteristic parameters calculated in step S3, a filter coefficient matrix is ​​generated for filtering the channel response at the receiving end.

2. The method for generating filter coefficients at the receiving end of a power line MIMO system based on subcarrier design as claimed in claim 1, characterized in that: In the process of generating the filter coefficient matrix, for the frequency domain channel response to be filtered, the subcarrier correspondence between the channel response after filtering is designed according to the MMSE filter order F: For the filtered channel subcarrier index q, if Set the starting position f of the subcarrier of the channel to be filtered a =1, the corresponding subcarrier index to be filtered is m∈{1,2,...,F}; For the filtered channel subcarrier index q, if Set the starting position f of the channel to be filtered a Starting from 1 to M-F+1, the subcarrier index to be filtered is m∈{f a ,f a +1,...,f a +F-1}; For the filtered channel subcarrier index q, if Set the starting position f of the channel to be filtered a =M-F+1, at this time the subcarrier index to be filtered is m∈{M-F+1,...,M}.

3. The method for generating filter coefficients at the receiving end of a power line MIMO system based on subcarrier design according to claim 1 or 2, characterized in that: For the time domain parameter estimation based on the subcarrier index to be filtered, when the subcarrier index q after filtering satisfies When the channel corresponding to the subcarrier index {1,2,...,F} in the matrix to be filtered is used Compute the time domain channel response use Estimate the signal-to-noise ratio and power delay profile and generate filter coefficients.

4. The method for generating filter coefficients at the receiving end of a power line MIMO system based on subcarrier design according to claim 1 or 2, characterized in that: For the time domain parameter estimation based on the subcarrier index to be filtered, when the subcarrier index q after filtering satisfies When, channel The starting position f of the subcarrier to be filtered a Starting from 1 to M-F+1, we can use the index {f a ,f a +1,...,f a +F-1} corresponding frequency domain channel Compute the time domain channel response use Estimate the signal-to-noise ratio and power delay profile and generate the filter vector w (F / 2)+1 ,...,w M-(F / 2) .

5. The method for generating filter coefficients at the receiving end of a power line MIMO system based on subcarrier design according to claim 1 or 2, characterized in that: For the time domain parameter estimation based on the subcarrier index to be filtered, when the subcarrier index q after filtering satisfies When using the frequency domain channel corresponding to the subcarrier index {M-F+1,...,M} Compute the time domain channel response use Estimate the signal-to-noise ratio and power delay profile and generate the filter vector w M-(F2) +1,...,w M .

6. The method for generating filter coefficients at the receiving end of a power line MIMO system based on subcarrier design according to any one of claims 1 to 5, characterized in that: For subcarrier design based on subband area division for time domain parameter estimation, the entire bandwidth is divided into J subbands with subcarriers, and the number of subcarriers in each subband is M. j ,j=1,2,...,J, where the subband where the subcarrier of the filtered channel is located is taken as the reference and the subband set where the subcarrier of the channel to be filtered is located is taken as the reference.

7. The method for generating filter coefficients at the receiving end of a power line MIMO system based on subcarrier design according to any one of claims 1 to 5, characterized in that: For the estimation of time domain characteristic parameters based on the subband where the subcarrier of the filtered channel is located, if the filtered channel response The subcarrier index q is located in subband j, then all subcarrier indexes in subband j are used The corresponding channel frequency response Compute the time domain channel response use Estimate the signal-to-noise ratio and power delay spectrum and generate the filter coefficient vector w q .

8. The method for generating filter coefficients at the receiving end of a power line MIMO system based on subcarrier design as claimed in claim 1, characterized in that: For the channel response to be filtered The sub-band where the sub-carrier index m is located is used as the reference for calculating the time domain characteristic parameters, and the time domain characteristic parameters are determined from f a to f a +F-1 all sub-bands where all sub-carriers are located, and all sub-bands are obtained. of Subbands. Using all subcarrier indices in the subband set The corresponding frequency domain channel response Compute the time domain channel response use Estimate the signal-to-noise ratio and power delay spectrum and generate the filter coefficient vector w q .

9. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method for generating filter coefficients at a receiving end of a power line MIMO system based on subcarrier design as described in any one of claims 1 to 8 is implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the method for generating filter coefficients at a receiving end of a power line MIMO system based on subcarrier design as described in any one of claims 1 to 8 is implemented.

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