CN118337315A

CN118337315A - Method, device, apparatus and storage medium for multipath interference suppression

Info

Publication number: CN118337315A
Application number: CN202310036087.7A
Authority: CN
Inventors: 林颖; 石璟
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2023-01-10
Filing date: 2023-01-10
Publication date: 2024-07-12

Abstract

The embodiment of the application provides a method, equipment, a device and a storage medium for restraining multipath interference, wherein the method comprises the following steps: acquiring a demodulation reference signal for realizing multiport multiplexing through a frequency domain orthogonal cover code OCC and a corresponding frequency domain signal stream; determining one or more peak time windows based on the time domain distribution of the least square estimation result corresponding to the frequency domain signal flow; screening out a time domain signal corresponding to a target channel based on a peak time window; and determining a result after the target channel performs multipath interference suppression based on a fast Fourier transform result of the time domain signal corresponding to the target channel. The application utilizes the characteristic of realizing the separation of the multi-port multiplexing streams in the time domain by using the frequency domain OCC, and after converting the frequency domain signal streams on different multiplexing ports to the time domain, suppresses the different frequency domain signal streams, thereby overcoming the multipath interference, further determining the result after multipath interference suppression, being applicable to the scene that each stream channel has more than one strong path, and having wider application range.

Description

Method, device, apparatus and storage medium for multipath interference suppression

Technical Field

The present application relates to the field of wireless communications technologies, and in particular, to a method, an apparatus, a device, and a storage medium for multipath interference suppression.

Background

In the 5G system, various modulation schemes are supported, such as 16Quadrature amplitude modulation (16Quadrature Amplitude Modulation,16QAM), 64QAM, 256QAM, and Quadrature phase shift keying (Quadrature PHASE SHIFT KEYING, QPSK). In order to increase the transmission rate, the highest code rate needs to be supported to 0.9258 by the high-order modulation in the modulation mode, such as 64QAM or 256 QAM.

These characteristics place higher demands on 5G data demodulation, mainly because higher order modulation (such as 64QAM or 256 QAM) has smaller distance between constellation points than other lower order modulation (such as 16QAM or QPSK, etc.), and small disturbance will interfere with other adjacent constellation points to cause erroneous judgment.

In the prior art, when inter-stream interference suppression is processed, only the situation that one strong path exists is considered, and in an actual scene, a plurality of strong paths appear along with the increase of time delay, at this time, if the interference suppression is carried out on the plurality of strong paths by using the scheme in the related art, the residual term is increased, so that the demodulation performance in a high-order modulation mode is affected.

Disclosure of Invention

Aiming at the problems existing in the prior art, the embodiment of the application provides a method, equipment, a device and a storage medium for restraining multipath interference.

In a first aspect, an embodiment of the present application provides a method for multipath interference suppression, including:

Acquiring a demodulation reference signal realizing multiport multiplexing through a frequency domain orthogonal cover code OCC and a frequency domain signal stream corresponding to the demodulation reference signal;

Determining one or more peak time windows based on the time domain distribution of the least square estimation result corresponding to the frequency domain signal flow;

Screening out a time domain signal corresponding to a target channel based on the peak time window;

and determining a result after the target channel carries out multipath interference suppression based on a fast Fourier transform result of the time domain signal corresponding to the target channel.

Optionally, the determining one or more peak time windows based on the time domain distribution of the least square estimation result corresponding to the frequency domain signal stream includes:

Determining the conjugate multiplication result of the frequency domain signal flow and the local base sequence, and taking the conjugate multiplication result as a least square method estimation result corresponding to the frequency domain signal flow;

and determining one or more peak time windows based on the time domain distribution corresponding to the least square estimation result.

Optionally, the determining one or more peak time windows based on the time domain distribution corresponding to the least square estimation result includes:

Determining a time domain signal corresponding to the least square method estimation result based on inverse fast fourier transform;

One or more peak time windows are determined based on the distribution of the magnitudes in the time-domain signal.

Optionally, the screening the time domain signal corresponding to the target channel based on the peak time window includes:

and screening out the time domain signal in any peak time window as the time domain signal corresponding to the target channel.

Optionally, the determining, based on the fast fourier transform result of the time domain signal corresponding to the target channel, a result of multipath interference suppression of the target channel includes:

Determining a fast Fourier transform result of a time domain signal corresponding to the target channel as a second frequency domain signal;

Replacing the values of the first N frequency points and the values of the last N frequency points in the second frequency domain signal with the values of the least square method estimation result corresponding to the frequency domain signal flow on the same frequency point, and taking the values as the result after the target channel carries out multipath interference suppression; and N is a positive integer.

Optionally, the frequency domain signal stream is a signal stream supporting single user multiple input multiple output SU-MIMO or a signal stream supporting multi user multiple input multiple output MU-MIMO.

In a second aspect, an embodiment of the present application further provides an electronic device, including a memory, a transceiver, and a processor;

A memory for storing a computer program; a transceiver for transceiving data under control of the processor; a processor for reading the computer program in the memory and performing the following operations:

In a third aspect, an embodiment of the present application further provides an apparatus for multipath interference suppression, including:

The acquisition module is used for acquiring a demodulation reference signal for realizing multi-port multiplexing through a frequency domain orthogonal cover code OCC and a frequency domain signal stream corresponding to the demodulation reference signal;

A first determining module, configured to determine one or more peak time windows based on a time domain distribution of a least square estimation result corresponding to the frequency domain signal stream;

The screening module is used for screening out a time domain signal corresponding to the target channel based on the peak time window;

and the second determining module is used for determining a result of the target channel after multipath interference suppression based on a fast Fourier transform result of the time domain signal corresponding to the target channel.

In a fourth aspect, embodiments of the present application further provide a computer-readable storage medium storing a computer program for causing a computer to perform the method for multipath interference suppression as described in the first aspect.

In a fifth aspect, an embodiment of the present application further provides a communication device, where a computer program is stored, where the computer program is configured to cause the communication device to perform the method for multipath interference suppression according to the first aspect as described above.

In a sixth aspect, embodiments of the present application further provide a processor-readable storage medium storing a computer program for causing a processor to perform the method of multipath interference suppression as described in the first aspect above.

In a seventh aspect, embodiments of the present application further provide a chip product, where a computer program is stored, where the computer program is configured to cause the chip product to perform the method for multipath interference suppression according to the first aspect as described above.

The method, the device, the apparatus and the storage medium for multipath interference suppression provided by the embodiment of the application utilize the characteristic that the multi-port multiplexing streams are separated in the time domain by using the frequency domain orthogonal cover code OCC, and after the frequency domain signal streams on different multiplexing ports are converted into the time domain, the different frequency domain signal streams are suppressed, so that the multipath interference is overcome, the result after multipath interference suppression is further determined, the method, the device and the storage medium are suitable for scenes with more than one strong path for each stream channel, the application range is wider, and the corresponding demodulation performance is obviously improved under the condition of more than one strong path.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the related art, the drawings that are required to be used in the embodiments or the related technical descriptions will be briefly described, and it is apparent that the drawings in the following descriptions are some embodiments of the present application, and other drawings may be obtained according to the drawings without inventive effort for those skilled in the art.

Fig. 1 is a flow chart of a method for multipath interference suppression according to an embodiment of the present application;

Fig. 2 is an overall flow chart of a method for multipath interference suppression according to an embodiment of the present application;

FIG. 3 is a schematic diagram of a channel estimation process in the related art;

Fig. 4 is a schematic diagram of a channel estimation process flow provided in the present application;

Fig. 5 is a schematic structural diagram of an electronic device according to an embodiment of the present application;

fig. 6 is a schematic structural diagram of an apparatus for multipath interference suppression according to an embodiment of the present application.

Detailed Description

In the embodiment of the application, the term "and/or" describes the association relation of the association objects, which means that three relations can exist, for example, a and/or B can be expressed as follows: a exists alone, A and B exist together, and B exists alone. The character "/" generally indicates that the context-dependent object is an "or" relationship.

The term "plurality" in embodiments of the present application means two or more, and other adjectives are similar.

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments, but not all embodiments of the present application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

In order to facilitate a clearer understanding of the technical solutions of the embodiments of the present application, some technical contents related to the embodiments of the present application will be first described.

In the fifth generation mobile communication (the 5th generation mobile communication,5G) system, the pilot frequency of the Physical Uplink SHARED CHANNEL, PUSCH is the Demodulation reference signal (Demodulation REFERENCE SIGNAL, DMRS), and since Multiple User Multiple-Input Multiple-Output (MU-MIMO) and Single User Multiple-Input Multiple-Output (SU-MIMO) are required to be supported, these different data signal streams all need to perform corresponding channel estimation to obtain the original transmission information of each data signal stream. If each data signal stream adopts a single DMRS, the network resource overhead is increased, and if a plurality of data signal streams multiplex the same DMRS, the resource overhead can be effectively reduced, and the transmission efficiency is improved. The method for multiplexing DMRS by different data signal streams in the 5G system mainly includes: frequency division, frequency domain orthogonal cover codes (Orthogonal Cover Code, OCC) and time domain OCC. Taking DMRS configuration type 1 as an example, see table 1:

Wherein CDM group (Code Division Multiplexing Group) is a code division multiplexing group. In Table 1, 0/1/4/5 and 2/3/6/7 frequency division multiplexing occupy different frequency domain resources respectively. Between 0/1 and 4/5 and between 2/3 and 6/7, by orthogonalization codes defined by W _t (l'). And between 0/1, 2/3, 4/5 and 6/7 are distinguished by the frequency domain OCC, and are realized by orthogonalization codes defined by W _f (k').

Assuming two data signal streams for the same user are distinguished on the pilot by frequency domain OCCs on port 0 and port 1, respectively. The frequency domain signals of two adjacent sample points received on the pilot symbol are examined and can be expressed as:

Wherein h ₀₀ corresponds to the channel coefficient of port 0 at Resource Element (RE) position k ₀, s ₀₀ corresponds to the signal of port 0 at RE position k ₀, h ₀₁ corresponds to the channel coefficient of port 0 at RE position k ₁, s ₀₁ corresponds to the signal of port 0 at RE position k ₁; h ₁₀ corresponds to the channel coefficient of port 1 at RE position k ₀, s ₁₀ corresponds to the signal of port 1 at RE position k ₀, h ₁₁ corresponds to the channel coefficient of port 1 at RE position k ₁, and s ₁₁ corresponds to the signal of port 1 at RE position k ₁. The channel coefficients represent performance parameters of the channel transceiver.

Again because:

Wherein i s ₀₀|＝|s₀₁ i=1.

When the timing offset (IN REAL TIME, IRT) is zero, h ₀₀≈h₀₁,h₁₀≈h₁₁ can be considered, and then the channel estimation result of data signal stream 0 and data signal stream 1 can be obtained by the following equation:

Whereas if there is a timing deviation of the channel through which the data signal stream 0 and the data signal stream 1 pass, and there is a distinguishable multipath, i.e., irt+.0, the above "h ₀₀≈h₀₁,h₁₀≈h₁₁" is not true, inter-stream interference is introduced if the channel estimation of the data signal stream 0 and the data signal stream 1 is also extracted according to equation (3). Taking h ₀₀ as an example, the error Δh ₀₀ of h ₀₀ can be theoretically expressed as follows:

the current scheme considers timing deviation when eliminating inter-stream interference, but assumes that each stream has only one strong path, and the specific method is as follows:

In case the timing deviation IRT is not equal to 0:

Wherein the plural number Determined by IRT, the formula isIn the above formula (5)Is the phase difference introduced by the data signal stream 0,Is the phase difference introduced by the data signal stream 1. It can be seen that when IRT+.0, inter-flow interference is introduced, i.e. for port 0, the perturbation term from port 1 is increasedFor port 1, the perturbation term from port 0 is added

The inter-stream interference cancellation formula is as follows:

can be directly used And (3) withAnd (5) performing equalization processing.

With the above formula, although interference cannot be completely eliminated, most of interference can be suppressed to a large extent in the case of a small IRT, and the following is taken as an example of the reason for port 0:

The original interference term is:

the residual interference term after interference cancellation is:

the above analysis method only considers the case of a single strong path, when there are multiple strong paths, such as two strong paths for example:

Based on the above relationship, the expressions of r ₀ and r ₁ are obtained as follows:

Above mentioned AndRepresenting the channels of the first root path and the second root path on RE0, respectively, on port 0.AndRepresenting the channels of the first root path and the second root path on RE0, port 1, respectively.AndRepresenting the channels of the first root path and the second root path on RE1, port 0, respectively.AndRepresenting the channels of the first root path and the second root path on RE1, respectively, on port 1. Wherein the root path represents a single point signal of a time domain impulse response formed at a certain moment.

At this time, for port 0, the interference term becomesAt this time, if the inter-stream interference is also eliminated using equation (6), the residual interference term is calculated as follows:

It can be seen that the residual interference term becomes large and that there is a non-square residual term, which can have a significant impact on performance and may not reach peak speed in 256QAM modulation schemes.

Fig. 1 is a flow chart of a method for multipath interference suppression according to an embodiment of the present application, as shown in fig. 1, the method includes:

step 101, obtaining a demodulation reference signal realizing multi-port multiplexing through a frequency domain orthogonal cover code OCC and a frequency domain signal stream corresponding to the demodulation reference signal;

Specifically, the application utilizes the characteristic that the frequency domain signal streams corresponding to the demodulation reference signals multiplexed by multiple ports are realized by adopting the frequency domain orthogonal cover code OCC and the peak areas are distributed separately in the time domain, firstly, the frequency domain signal streams are converted into the time domain, other interference signals are filtered through corresponding time windows by utilizing different areas where the peaks are positioned, and then the time domain signals with the interference signals filtered are converted into the frequency domain, so that the result after multipath interference suppression is obtained.

The method comprises the steps of obtaining a demodulation reference signal which realizes multiport multiplexing through a frequency domain orthogonal cover code OCC and frequency domain signal streams corresponding to the demodulation reference signal, wherein the frequency domain signal streams are continuous, and obtaining discrete frequency domain signal streams corresponding to the continuous frequency domain signal streams in a sampling mode for realizing analysis of the frequency domain signal streams more simply. A continuous signal can be represented entirely by the values or samples of the signal at equal time intervals and the signal can be recovered entirely by the sample values. I.e. the discrete frequency domain signal streams can also characterize the correlation properties of the corresponding continuous frequency domain signal streams. There may be various manners of representing the discrete frequency domain signal stream, for example, in a noise scenario, the discrete frequency domain signal stream Y may be represented as:

Y ＝ H*W_f*S + N (12)

Wherein Y represents a discrete frequency domain signal, H represents a channel matrix corresponding to a channel of signal transmission sent by a terminal, W _f is a frequency domain OCC multiplexing code, S is a local base sequence, and N is a noise signal.

102, Determining one or more peak time windows based on the time domain distribution of the least square estimation result corresponding to the frequency domain signal flow;

According to the discrete frequency domain signal flow Y, determining the time domain distribution of the corresponding least square method estimation result, and possibly, in one or more time periods, there are peaks corresponding to signals, where the peaks mainly represent that the first amplitude exceeds p% (a preset percentage) of the second amplitude, or that the first amplitude exceeds p% of the third amplitude, where the first amplitude is the amplitude of the signal at the current moment, the second amplitude is the average amplitude of the signal in the period of time t ₀ adjacent to the current moment, the third amplitude is the average amplitude of the signal in the period of time t ₀ adjacent to the current moment, where p% represents the preset percentage, an initial value may be configured, and the peak is adjusted according to the subsequent result, typically about 10%, where the period t ₀ is related to the time interval of sampling, and the greater the sampling time interval is, the greater the corresponding period t ₀ is. Of course, the peak value is also understood to mean that there is a distribution of signals in a certain period or a certain periods, and the distribution of signals in other periods is considered to be absent; the distribution of the signal that exists over a certain period or periods of time, i.e. the amplitude of the signal is typically greater than a over the corresponding period of time; for other periods of time, no signal is considered to be distributed, in which case the amplitude of the signal is typically less than B, where the minimum value of a is typically p% or more of B, and both a and B are positive numbers; the p% is a preset percentage, and can take a value of 10%, and can be adjusted according to the actual signal strength. For example, when the signal distribution exists and the corresponding signal amplitude is larger, generally greater than 20, the predetermined percentage may be 5%. The time period includes specific starting time and ending time. In this way, according to the distribution of the signal amplitude, a specific start-stop time corresponding to the peak area corresponding to the signal, namely a time window corresponding to the peak, is determined, and the time window is simply called as a peak time window in the application.

In addition, the peak value corresponding to the signal exists in one or more time periods, and it is also possible to determine a time window width according to a preset rule based on the number of resource blocks occupied by each frequency domain signal stream, determine the offset position of a window based on the number of ports multiplexed by the demodulation reference signal corresponding to the frequency domain signal stream and the number of resource units for scheduling the demodulation reference signal, and determine one or more time windows according to the frequency shift position of the window and the time window width, so as to form the peak value time window.

Step 103, screening out a time domain signal corresponding to a target channel based on the peak time window;

And determining different peak time windows corresponding to different time periods, then determining a target channel to be screened, further screening out time domain signals corresponding to the target channel according to the different peak time windows, and filtering out signals of other channels through removing the peak time windows corresponding to the channels except the target channel. It can be simply understood that the time domain signals corresponding to other peak time windows are zeroed out.

Step 104, determining a result of the target channel after multipath interference suppression based on a fast fourier transform result of the time domain signal corresponding to the target channel.

After the time domain signal corresponding to the target channel is screened out through the steps, a fast Fourier transform (Fast Fourier Transform, FFT) result corresponding to the time domain signal is determined, so that a result after multipath interference suppression of the target channel is obtained.

The method for restraining the multipath interference provided by the embodiment of the application utilizes the characteristic that the multi-port multiplexing streams are separated in the time domain by using the frequency domain orthogonal cover code OCC, and restrains the separated partial time domain signals after the interleaving frequency domain signal streams passing through the multiplexing ports are converted into the time domain, thereby overcoming the multipath interference, further determining the result after restraining the multipath interference, being applicable to the scene that each stream channel has more than one strong path interference, having wider application range and obviously improving the corresponding demodulation performance under the condition of more than one strong path.

Specifically, the discrete signal corresponding to the above-mentioned frequency domain signal stream may be denoted as Y, and when channel estimation is performed on the discrete frequency domain signal stream, first, a Least Square (LS) estimation is performed, and specifically, by conjugate multiplying the discrete frequency domain signal stream with a local base sequence, a Least square estimation result H _LS is obtained as follows:

H_LS＝Y*S^*＝H*W_f*S*S^*+N*S^*＝H*W_f*|S|+N′ (13)

Wherein, |s|=1, N' =n×s ^*, and further determining a time domain distribution corresponding to the least square estimation result H _LS, where the time domain distribution mainly refers to a specific distribution of amplitudes corresponding to signals at different time instants in a time domain, and it is determined that, in a certain time period or a certain time periods, there is a peak value of the signals, where the peak value mainly indicates that the first amplitude exceeds p% of the second amplitude, or the first amplitude exceeds p% of the third amplitude, where the first amplitude is an amplitude of the signal at the current time instant, the second amplitude is an average amplitude of the signal in a time period of t ₀ before the current time instant, and the third amplitude is an average amplitude of the signal in a time period of t ₀ after the current time instant, or the distribution of the signals exists in a certain time period or a certain time period, that is, the amplitude of the signal is generally greater than a in the corresponding time period; if no signal distribution exists in other time periods, the amplitude of the signal is usually smaller than B, the minimum value of A is usually more than or equal to p% of B, and both A and B are positive numbers; the p% is a preset percentage, and can take a value of 10%, and can be adjusted according to the actual signal strength.

Specifically, the time domain distribution corresponding to the least square estimation result is determined by taking the least square estimation result as an input of inverse fast fourier transform (INVERSE FAST Fourier Transform, IFFT) to obtain a time domain signal, determining the distribution of the amplitude in the time domain signal, and determining one or more existing peak time windows.

The time domain signal is obtained by performing IFFT transformation on the frequency domain signal streams corresponding to the demodulation reference signals which are multiplexed by the frequency domain orthogonal cover code OCC, the frequency domain signal streams are interleaved in the frequency domain, and a plurality of frequency domain signal streams of a plurality of users or a plurality of frequency domain signal streams of the same user may exist. The corresponding time domain signal of each frequency domain signal flow has corresponding amplitude distribution in different time periods, and the amplitude is generally larger than B. And under the condition that the frequency domain signal flow does not correspond to the time domain signal, the amplitude of the time domain signal in the corresponding time domain waveform diagram is generally smaller than A. And the minimum value of A is usually greater than or equal to the preset percentage of B, and both A and B are positive numbers; the preset percentage can take a value of 10%, and can be adjusted according to the actual signal strength.

Specifically determining the one or more peak time windows, taking the peak time window width according to the formula based on the number of Resource Blocks (RBs) scheduled by the user: floor (1.5×rb _Num):floor(2.5*RB_Num), the offset position of the window is determined according to "layer_idx×n _sum/2".

The above RBs _Num identify the number of RBs scheduled by the user, floor represents a rounding down, layer_idx represents an index value of the frequency domain signal stream, which includes how many frequency domain signal streams interleaved together, the index value includes how many, or how many ports the demodulation reference signal corresponding to the frequency domain signal stream has, and the index value includes how many. For example, the frequency domain signal stream includes two streams interleaved together, and the value of layer_idx is 0 or 1, n _sum represents the total number of samples, that is, the total number of Resource Elements (REs) of the pilot scheduling corresponding to the frequency domain signal, and generally, the pilot number=rb number of the 5G system is x 6.

In addition, determining the one or more peak time windows may further determine that the amplitude of the current time of the time-domain signal exceeds p% of the amplitude of the signal in the adjacent previous t ₀ time period, or that the amplitude of the signal at the current time exceeds p% of the amplitude of the signal in the adjacent subsequent t ₀ time period, where p% is a preset percentage, an initial value may be configured, and the adjustment is performed according to the subsequent result, typically about 10%, where the time period t ₀ is related to the time interval of sampling, and the greater the sampling time interval, the greater the corresponding time period t ₀. Or the amplitude of the signal is typically greater than a for some period or periods of time; the amplitude of the signal in other time periods is usually smaller than B, the minimum value of A is usually more than or equal to p% of B, and both A and B are positive numbers; the p% is a preset percentage, and can take a value of 10%, and can be adjusted according to the actual signal strength.

Specifically, the discrete frequency domain signal stream Y may be transmitted through a plurality of frequency domain signal stream multiplexing ports corresponding to a plurality of users, or may be transmitted through a plurality of frequency domain signal stream multiplexing ports of the same user. To specifically screen out a certain frequency domain signal stream of a certain user, other frequency domain signal streams transmitted through the multiplexing port need to be separated. The method for restraining multipath interference provided by the application converts the discrete frequency domain signal streams into time domains, and the time domain signals corresponding to each frequency domain signal stream are distributed separately in different time periods, and each peak time window corresponds to the distribution of one time domain signal, so that the time domain signals corresponding to the target frequency domain signal can be screened out directly through a specific peak time window, wherein the specific peak time window has a corresponding relation with the target frequency domain signal. Or setting the time domain signals in other peak time windows to zero through other peak time windows except the specific peak time window, so as to directly screen out the time domain signals corresponding to the specific peak time window. Because different frequency domain signals correspond to different channels, the different channels also represent different frequency domain signals, and the time domain signals corresponding to the target frequency domain signals are screened out and can be understood as the time domain signals corresponding to the target channels.

Specifically, after determining the time domain signal corresponding to the target channel, a fast fourier transform FFT is adopted, when determining the FFT result of the time domain signal corresponding to the target channel, that is, when converting the time domain signal into the frequency domain, there may be a gibbs effect, and in order to reduce this situation, generally, a value of the least square estimation result corresponding to the frequency domain signal stream on the same frequency point is directly adopted at an edge sample point of the FFT result of the time domain signal corresponding to the target channel. Namely, taking the fast Fourier transform result of the time domain signal corresponding to the target channel as a second frequency domain signal; replacing the values of the first N frequency points and the values of the last N frequency points in the second frequency domain signal with the values of the least square method estimation result corresponding to the frequency domain signal flow on the same frequency point, and taking the values as the result after the target channel carries out multipath interference suppression; and N is a positive integer. The value of N may be set or configured to an initial value based on empirical values, and the subsequent execution process is adjusted step by step.

Optionally, the frequency domain signal stream is transmitted by using multi-port multiplexing, and may be a signal stream supporting single-user multiple-input multiple-output SU-MIMO or a signal stream supporting multi-user multiple-input multiple-output MU-MIMO. That is, the multiple frequency domain signal streams of the same user are transmitted after interleaving, or the multiple frequency domain signal streams of multiple users are transmitted after interleaving.

The method for restraining the multipath interference provided by the embodiment of the application utilizes the characteristic that the multi-port multiplexing streams are separated in the time domain by using the frequency domain orthogonal cover code OCC, and restrains different frequency domain signal streams after converting the frequency domain signal streams on different multiplexing ports into the time domain, thereby overcoming the multipath interference, further determining the result after restraining the multipath interference, being applicable to the scene with more than one strong path of each stream channel, having wider application range and obviously improving the corresponding demodulation performance under the condition of more than one strong path.

Fig. 2 is an overall flow chart of a method for multipath interference suppression according to an embodiment of the present application, as shown in fig. 2, specifically including:

Step 201, obtaining a frequency domain signal stream corresponding to a demodulation reference signal for realizing multi-port multiplexing by using a frequency domain orthogonal cover code OCC as a first signal, and performing least square estimation.

Step 202, determining the conjugate product of the first signal and the local base sequence as a corresponding least square estimation result H _LS;

Step 203, determining a result corresponding to the least square estimation result H _LS, that is, the distribution of the time domain signal, based on the inverse fast fourier transform;

Step 204, determining a time window corresponding to the amplitude of the time domain signal which is separately distributed as a peak time window based on the distribution of the time domain signal; filtering the time domain signals according to the peak time window to determine the time domain signals corresponding to the target channels, and also can be understood as screening out the time domain signals corresponding to the single peak time window;

step 205, determining a fast fourier transform result corresponding to the filtered time domain signal, namely a corresponding frequency domain signal, based on the fast fourier transform;

Step 206, capturing points of intermediate frequency point positions of the frequency domain signal and determining which edge frequency points are deleted in order to reduce the influence of the Gibbs effect which may exist when the frequency domain signal obtained in step 205 is converted back to the frequency domain;

Step 207, screening out frequency domain signals corresponding to the edge frequency points deleted in the step 206 from the least square method estimation result in the step 202;

step 208, combining the frequency domain signal corresponding to the point of the middle frequency point position of the frequency domain signal obtained in step 206 and the frequency domain signal corresponding to the edge frequency point in step 207 into a final multipath interference suppressed result.

FIG. 3 is a schematic diagram of a channel estimation process in the related art; the method mainly processes the signal with single-path interference, as shown in fig. 3, and specifically includes:

Step 301, obtaining a demodulation reference signal and a frequency domain signal stream corresponding to the demodulation reference signal, inputting the demodulation reference signal and the frequency domain signal stream into a least square estimation module, and obtaining a corresponding least square estimation result H _LS based on a conjugate multiplication result of the frequency domain signal stream and a local base sequence;

Step 302, solving the orthogonal cover code OCC by the least square method estimation result H _LS obtained in step 301;

step 303, performing interference suppression, namely directly performing interference suppression on the frequency domain signal, which may cause a plurality of residual interference terms;

And 304, performing Minimum Mean Square Error (MMSE) filtering on the interference suppression result to obtain a final interference suppression result.

Fig. 4 is a schematic diagram of a channel estimation process provided in the present application, as shown in fig. 4, specifically including:

Step 401, obtaining a demodulation reference signal and a frequency domain signal stream corresponding to the demodulation reference signal, inputting the frequency domain signal stream and the frequency domain signal stream into a least square estimation module, and obtaining a corresponding least square estimation result H _LS based on a conjugate multiplication result of the frequency domain signal stream and a local base sequence; this step is the same as step 301 in fig. 3.

Step 402, performing multipath interference suppression on the obtained least square method estimation result H _LS; the specific operation steps are the same as steps 202 to 208 in fig. 2; after converting the frequency domain signal into the time domain, filtering the multipath interference through a peak time window, converting the frequency domain signal into the frequency domain, and replacing the frequency domain signal of the same frequency point in the original least square estimation result by the signal of the edge frequency point after converting the time domain signal corresponding to the peak time window into the frequency domain in consideration of the Gibbs effect existing when converting back into the frequency domain.

Step 403, the orthogonal cover code OCC is solved;

And 404, performing minimum mean square error filtering on the interference suppression result to obtain a final interference suppression result.

The application also simulates the multipath interference suppression method provided by the application by a simulation method, mainly simulates the condition that a single user schedules two frequency domain signal streams in a 5G network, the number of scheduled Resource Blocks (RB) is fixed to be 25, channels (Clustered DELAY LINE-typeC models, CDL-C) with non-direct paths are configured, time delay expansion configurations are respectively 500ns and 1000ns, for example, the scheme of fig. 3 and the scheme of fig. 4 simulate demodulation performance when the modulation and coding strategy (Modulation and Coding Scheme, MCS) is 27 steps, so that the signals processed by the scheme of fig. 3 can be seen and cannot be converged to a Block Error Rate (BLER) of 10%, namely, the peak speed cannot be reached. As in the case of the signal processed by the scheme of fig. 4, the convergence characteristics are good, approaching a block error rate BLER of 10%.

Fig. 5 is a schematic structural diagram of an electronic device according to an embodiment of the present application, and as shown in fig. 5, the electronic device includes a memory 520, a transceiver 510, and a processor 500; wherein the processor 500 and the memory 520 may also be physically separate.

A memory 520 for storing a computer program; a transceiver 510 for transceiving data under the control of the processor 500. A processor 500 for reading the computer program in the memory 520 and performing the following operations:

In particular, the transceiver 510 is used to receive and transmit data under the control of the processor 500.

Wherein in fig. 5, a bus architecture may comprise any number of interconnected buses and bridges, and in particular one or more processors represented by processor 500 and various circuits of memory represented by memory 520, linked together. The bus architecture may also link together various other circuits such as peripheral devices, voltage regulators, power management circuits, etc., all as are well known in the art and, therefore, will not be described further herein. The bus interface provides an interface. The transceiver 510 may be a number of elements, including a transmitter and a receiver, providing a means for communicating with various other apparatus over transmission media, including wireless channels, wired channels, optical cables, and the like.

The processor 500 is responsible for managing the bus architecture and general processing, and the memory 520 may store data used by the processor 500 in performing operations.

The processor 500 may be a central processing unit (Central Processing Unit, CPU), application SPECIFIC INTEGRATED Circuit (ASIC), field-Programmable gate array (Field-Programmable GATE ARRAY, FPGA), or complex Programmable logic device (Complex Programmable Logic Device, CPLD), and may also employ a multi-core architecture.

The processor 500 is operable to perform any of the methods provided by embodiments of the present application in accordance with the obtained executable instructions by invoking a computer program stored in the memory 520. The processor and the memory may also be physically separate.

It should be noted that, the electronic device provided in the embodiment of the present application can implement all the method steps implemented in the method embodiment and achieve the same technical effects, and the parts and beneficial effects that are the same as those of the method embodiment in the embodiment are not described in detail herein.

Fig. 6 is a schematic structural diagram of an apparatus for multipath interference suppression according to an embodiment of the present application, as shown in fig. 6, the apparatus includes:

The acquisition module 601 acquires a demodulation reference signal realizing multi-port multiplexing through a frequency domain orthogonal cover code OCC and a frequency domain signal stream corresponding to the demodulation reference signal;

A first determining module 602, configured to determine one or more peak time windows based on a time domain distribution of a least square estimation result corresponding to the frequency domain signal stream;

a screening module 603, configured to screen out a time domain signal corresponding to the target channel based on the peak time window;

a second determining module 604, configured to determine a result of multipath interference suppression performed on the target channel based on a fast fourier transform result of the time domain signal corresponding to the target channel.

Optionally, the first determining module 602 is specifically configured to, in determining one or more peak time windows based on a time domain distribution of the least square estimation result corresponding to the frequency domain signal stream:

Optionally, the first determining module 602 is specifically configured to, in determining one or more peak time windows based on the time domain distribution corresponding to the least square estimation result:

Optionally, the screening module 603 is specifically configured to, during screening out the time domain signal corresponding to the target channel based on the peak time window:

Optionally, the second determining module 604 is specifically configured to, in a process of determining a result of multipath interference suppression of the target channel based on a fast fourier transform result of the time domain signal corresponding to the target channel:

The method and the device provided by the embodiments of the present application are based on the same application conception, and because the principles of solving the problems by the method and the device are similar, the implementation of the device and the method can be referred to each other, and the repetition is not repeated.

It should be noted that, in the embodiment of the present application, the division of the units is schematic, which is merely a logic function division, and other division manners may be implemented in actual practice. In addition, each functional unit in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

The integrated units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a processor-readable storage medium. Based on such understanding, the technical solution of the present application may be embodied in essence or a part contributing to the prior art or all or part of the technical solution in the form of a software product stored in a storage medium, including several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) or a processor (processor) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a random access Memory (Random Access Memory, RAM), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

It should be noted that, the above device provided in the embodiment of the present application can implement all the method steps implemented in the method embodiment and achieve the same technical effects, and detailed descriptions of the same parts and beneficial effects as those in the method embodiment in this embodiment are omitted.

In another aspect, embodiments of the present application further provide a computer-readable storage medium storing a computer program for causing a computer to execute the method for multipath interference suppression provided in the above embodiments.

It should be noted that, the computer readable storage medium provided in the embodiment of the present application can implement all the method steps implemented in the above method embodiment and achieve the same technical effects, and detailed descriptions of the same parts and beneficial effects as those in the method embodiment in this embodiment are omitted.

The computer-readable storage medium can be any available medium or data storage device that can be accessed by a computer, including, but not limited to, magnetic storage (e.g., floppy disks, hard disks, magnetic tape, magneto-optical disks (MOs), etc.), optical storage (e.g., CD, DVD, BD, HVD, etc.), and semiconductor storage (e.g., ROM, EPROM, EEPROM, nonvolatile storage (NAND FLASH), solid State Disk (SSD)), etc.

The technical scheme provided by the embodiment of the application can be suitable for various systems, in particular to a 5G system. For example, applicable systems may be global system for mobile communications (global system of mobile communication, GSM), code division multiple access (code division multiple access, CDMA), wideband code division multiple access (Wideband Code Division Multiple Access, WCDMA) universal packet Radio service (GENERAL PACKET Radio service, GPRS), long term evolution (long term evolution, LTE), LTE frequency division duplex (frequency division duplex, FDD), LTE time division duplex (time division duplex, TDD), long term evolution-advanced (long term evolution advanced, LTE-a), universal mobile system (universal mobile telecommunication system, UMTS), worldwide interoperability for microwave access (worldwide interoperability for microwave access, wiMAX), 5G New air interface (New Radio, NR) systems, and the like. Terminal devices and network devices are included in these various systems. Core network parts such as evolved packet system (Evloved PACKET SYSTEM, EPS), 5G system (5 GS), etc. may also be included in the system.

The access network device (or referred to as network device) according to the embodiments of the present application may be a base station, where the base station may include a plurality of cells for providing services for terminals. A base station may also be called an access point or may be a device in an access network that communicates over the air-interface, through one or more sectors, with wireless terminal devices, or other names, depending on the particular application. The access network device may be configured to exchange received air frames with internet protocol (Internet Protocol, IP) packets as a router between the wireless terminal device and the rest of the access network, which may include an Internet Protocol (IP) communication network. The access network device may also coordinate attribute management for the air interface. For example, the access network device according to the embodiment of the present application may be a network device (Base Transceiver Station, BTS) in a global system for mobile communications (Global System for Mobile communications, GSM) or code division multiple access (Code Division Multiple Access, CDMA), a network device (NodeB) in a wideband code division multiple access (Wide-band Code Division Multiple Access, WCDMA), an evolved network device (evolutional Node B, eNB or e-NodeB) in a long term evolution (long term evolution, LTE) system, a 5G base station (gNB) in a 5G network architecture (next generation system), a home evolved base station (Home evolved Node B, heNB), a relay node (relay node), a home base station (femto), a pico base station (pico), and the like. In some network structures, the access network device may include a centralized unit (centralized unit, CU) node and a Distributed Unit (DU) node, which may also be geographically separated.

It will be appreciated by those skilled in the art that embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, magnetic disk storage, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer-executable instructions. These computer-executable instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These processor-executable instructions may also be stored in a processor-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the processor-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These processor-executable instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

It will be apparent to those skilled in the art that various modifications and variations can be made to the present application without departing from the spirit or scope of the application. Thus, it is intended that the present application also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

Claims

1. A method of multipath interference suppression, comprising:

2. The method of multipath interference suppression according to claim 1, wherein said determining one or more peak time windows based on a time domain distribution of the least squares estimation results for the frequency domain signal streams comprises:

3. The method of multipath interference suppression according to claim 2, wherein said determining one or more peak time windows based on the time domain distribution corresponding to the least squares estimation result comprises:

4. The method of multipath interference suppression according to claim 1, wherein the screening out the time domain signal corresponding to the target channel based on the peak time window includes:

5. The method of multipath interference suppression according to claim 1, wherein the determining the result of multipath interference suppression by the target channel based on the fast fourier transform result of the time domain signal corresponding to the target channel includes:

6. The method of multipath interference suppression according to claim 1, wherein the frequency domain signal stream is a signal stream supporting single user multiple input multiple output SU-MIMO or a signal stream supporting multi-user multiple input multiple output MU-MIMO.

7. An electronic device comprising a memory, a transceiver, and a processor;

8. The electronic device of claim 7, wherein the determining one or more peak time windows based on the time domain distribution of the least squares estimation result for the frequency domain signal stream comprises:

9. The electronic device of claim 8, wherein the determining one or more peak time windows based on the time domain distribution corresponding to the least squares estimation result comprises:

10. The electronic device of claim 7, wherein the screening the time domain signal corresponding to the target channel based on the peak time window comprises:

11. The electronic device of claim 7, wherein the determining the result of the target channel after multipath interference suppression based on the fast fourier transform result of the time domain signal corresponding to the target channel comprises:

12. The electronic device of claim 7, wherein the frequency domain signal stream is a signal stream supporting single user multiple input multiple output SU-MIMO or a signal stream supporting multi-user multiple input multiple output MU-MIMO.

13. An apparatus for multipath interference suppression, comprising:

14. A computer-readable storage medium, characterized in that the computer-readable storage medium stores a computer program for causing a computer to execute the method of multipath interference suppression according to any one of claims 1 to 6.