Channel detection method and device and computer readable storage medium

Abstract

The invention discloses a channel detection method and device and a computer readable storage medium, and is applied to the field of mobile communication, and the method comprises the steps: a transmitting end obtains an AFDM signal containing a detection signal and a guard interval according to the characteristics of a to-be-detected channel, and transmits the AFDM signal to a receiving end through the to-be-detected channel, and a receiving end carries out threshold judgment on the AFDM signal to obtain gain, time delay and Doppler frequency shift, and Monte Carlo statistical analysis is carried out to obtain a power time delay spectrum and a Doppler power spectrum of the to-be-detected channel. According to the method, the AFDM waveform is used for detecting the channel, so that the real-time performance and accuracy of channel detection can be ensured in a high-dynamic scene; the gain, the time delay and the Doppler frequency shift of the channel are directly obtained without additional processing steps, so that the power time delay spectrum and the Doppler power spectrum of the channel are obtained, and the channel detection efficiency is improved; in addition, integration of communication waveforms and detection waveforms is realized, resources are saved, and efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the field of mobile communications, and in particular to a channel detection method, device and computer-readable storage medium. Background Art

[0002] Traditional channel detection schemes are mainly based on pseudo-random (PN) sequence correlation methods. The core principle of this method is that the transmitter uses a pre-known PN sequence to perform correlation operations with the received signal, and judges the state of the channel by analyzing the strength of the correlation output, so as to optimize and improve the communication system. However, in high-dynamic scenarios, such as mobile communications, drone communications, and vehicle networking applications, the channel changes very quickly and may change multiple times within a few milliseconds. In this case, traditional PN sequence correlation methods often find it difficult to meet the requirements of real-time performance and accuracy. Due to the high-speed channel changes, the channel information obtained in the traditional method quickly loses its practical value.

[0003] Considering the limitations of traditional PN sequence detection methods in high dynamic scenarios, it is urgent to study new channel detection methods. Summary of the invention

[0004] In view of this, an object of the present invention is to provide a channel detection method, device and computer-readable storage medium, which solve the problem that the prior art cannot meet the accuracy and real-time performance of channel detection in high dynamic scenarios.

[0005] In order to solve the above technical problems, the present invention provides a channel detection method, comprising:

[0006] Obtaining an AFDM signal including a detection signal and a guard interval according to the characteristics of the channel to be detected;

[0007] The AFDM signal is sent to the receiving end through the channel to be detected so that the receiving end obtains the AFDM signal, and threshold judgment is performed on the AFDM signal to obtain gain, delay and Doppler frequency shift, and Monte Carlo statistical analysis is performed on the gain, delay and Doppler frequency shift to obtain the power delay spectrum and Doppler power spectrum of the channel to be detected.

[0008] Optionally, obtaining an AFDM signal including a detection signal and a guard interval according to the characteristics of the channel to be detected includes:

[0009] Determine the maximum multipath delay, the maximum moving speed and the carrier frequency according to the channel to be detected;

[0010] The maximum Doppler shift is calculated according to the maximum moving speed, the carrier frequency and the speed of light;

[0011] The length, bandwidth and DAFT conversion parameter values ​​of the AFDM signal are determined according to the maximum multipath delay and the maximum Doppler frequency shift, wherein the DAFT conversion parameter values ​​include a first parameter value and the second parameter value ;

[0012] The detection signal is inserted into the AFDM signal with the determined length, bandwidth and parameter value, and the guard interval of the preset length is respectively inserted on both sides of the detection signal to obtain the AFDM signal.

[0013] Optionally, the preset length is greater than or equal to a first length, and the calculation formula of the first length is:

[0014] ;

[0015] in, Indicates the first length, represents the integer part of the maximum multipath delay after normalization of the delay resolution, Represents the integer part of the maximum Doppler shift after normalization of the Doppler shift resolution.

[0016] The present invention also provides another channel detection method, which is applied to a receiving end and includes:

[0017] Receiving an AFDM signal sent by a transmitting end through a channel to be detected, wherein the AFDM signal is the AFDM signal including a detection signal and a guard interval obtained by the transmitting end according to the characteristics of the channel to be detected;

[0018] Threshold decision is performed on the AFDM signal to obtain gain, delay and Doppler frequency shift, and Monte Carlo statistical analysis is performed on the gain, delay and Doppler frequency shift to obtain a power delay spectrum and a Doppler power spectrum of the channel to be detected.

[0019] Optionally, performing threshold judgment on the AFDM signal to obtain gain, delay and Doppler frequency shift, and performing Monte Carlo statistical analysis on the gain, the delay and the Doppler frequency shift to obtain a power delay spectrum and a Doppler power spectrum of the channel to be detected, including:

[0020] Determine a first parameter value of DAFT transformation by using the AFDM signal The positive and negative situation;

[0021] If the first parameter value is a positive number, then the detection signal and the left guard interval of the detection signal are located in the decision area;

[0022] When the first parameter value is a negative number, the detection signal and the location of the right guard interval of the detection signal are the decision area;

[0023] Setting a decision threshold, and traversing each position of the decision area, and taking the position whose energy value is greater than the decision threshold as the position to be analyzed;

[0024] Obtaining the time delay and Doppler frequency shift of the path corresponding to the position to be analyzed;

[0025] Calculating the gain of the path corresponding to the position to be analyzed;

[0026] Monte Carlo statistics are performed multiple times on the time delay, the Doppler frequency shift and the gain to obtain the power delay spectrum and the Doppler power spectrum of the path corresponding to the position to be analyzed.

[0027] Optionally, the first parameter value of the DAFT transformation is determined by the AFDM signal The positive and negative conditions include:

[0028] The first parameter value The calculation formula is:

[0029] ;

[0030] in, represents the integer part of the normalized maximum Doppler shift, Indicates the length of the AFDM sequence.

[0031] The present invention also provides a channel detection device, applied to a transmitting end, comprising:

[0032] An AFDM sequence acquisition module, used for obtaining an AFDM signal including a detection signal and a guard interval according to the characteristics of the channel to be detected;

[0033] The sending module is used to send the AFDM signal to the receiving end through the channel to be detected so that the receiving end obtains the AFDM signal, and performs threshold judgment on the AFDM signal to obtain gain, delay and Doppler frequency shift, and performs Monte Carlo statistical analysis on the gain, the delay and the Doppler frequency shift to obtain the power delay spectrum and Doppler power spectrum of the channel to be detected.

[0034] The present invention also provides another channel detection device, which is applied to a receiving end and includes:

[0035] A receiving module, used for receiving an AFDM signal sent by a transmitting end through a channel to be detected, wherein the AFDM signal is the AFDM signal including a detection signal and a guard interval obtained by the transmitting end according to the characteristics of the channel to be detected;

[0036] The decision analysis module is used to perform threshold decision on the AFDM signal to obtain gain, delay and Doppler frequency shift, and perform Monte Carlo statistical analysis on the gain, delay and Doppler frequency shift to obtain the power delay spectrum and Doppler power spectrum of the channel to be detected.

[0037] Optionally, the judgment analysis module includes:

[0038] A positive and negative determination unit, used to determine the first parameter value of the DAFT transformation through the AFDM signal The positive and negative situation;

[0039] The first decision area determination unit is used to determine the first parameter value if is a positive number, then the detection signal and the left guard interval of the detection signal are located in the decision area;

[0040] The second decision area determination unit is used to determine the first parameter value when is a negative number, the detection signal and the location of the right guard interval of the detection signal are the decision area;

[0041] A decision unit, used to set a decision threshold, and traverse each position of the decision area, and take the position with energy value greater than the decision threshold as the position to be analyzed;

[0042] An acquisition unit, used to acquire the time delay and Doppler frequency shift of the path corresponding to the position to be analyzed;

[0043] A gain calculation unit, used to calculate the gain of the path corresponding to the position to be analyzed;

[0044] A statistical unit is used to perform multiple Monte Carlo statistics on the time delay, the Doppler frequency shift and the gain to obtain the power delay spectrum and the Doppler power spectrum of the path corresponding to the position to be analyzed.

[0045] The present invention also provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are loaded and executed by a processor, the channel detection method as described above is implemented.

[0046] It can be seen that the present invention obtains an AFDM signal including a detection signal and a guard interval inserted into the AFDM signal according to the characteristics of the channel to be detected through the transmitting end; the AFDM signal is sent to the receiving end through the channel to be detected, so that the receiving end obtains the AFDM signal, and the AFDM signal is threshold judged to obtain the gain, delay and Doppler frequency shift, and the gain, delay and Doppler frequency shift are subjected to Monte Carlo statistical analysis to obtain the power delay spectrum and Doppler power spectrum of the channel to be detected. The present method uses the AFDM waveform to detect the channel, so that the real-time and accuracy of the channel detection can be guaranteed in high dynamic scenarios; compared with the traditional PN sequence-based and OFDM-based channel detection methods, the present method can directly obtain the gain, delay and Doppler frequency shift of the channel, and further obtain the power delay spectrum and Doppler power spectrum of the channel without going through additional processing steps, thereby improving the efficiency of channel detection; and the communication waveform is combined with the detection waveform to realize the integration of the two, and communication and detection are realized together, which saves resources and improves efficiency.

[0047] In addition, the present invention also provides a channel detection device, equipment and computer-readable storage medium, which also have the above-mentioned beneficial effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0049] Figure 1 A flow chart of a channel detection method provided by an embodiment of the present invention;

[0050] Figure 2 A flow chart of another channel detection method provided by an embodiment of the present invention;

[0051] Figure 3 An example diagram of an AFDM signal sent by a transmitting end provided in an embodiment of the present invention;

[0052] Figure 4 An example diagram of an AFDM signal received by a receiving end provided in an embodiment of the present invention;

[0053] Figure 5 A comparison diagram of an estimated power delay spectrum and a theoretical power delay spectrum obtained by simulating an smTUx6c1 channel model provided in an embodiment of the present invention;

[0054] Figure 6A comparison diagram of an estimated Doppler power spectrum and a theoretical Doppler power spectrum obtained by simulating an smTUx6c1 channel model provided in an embodiment of the present invention;

[0055] Figure 7 A schematic diagram of the structure of a channel detection device provided by an embodiment of the present invention;

[0056] Figure 8 A schematic diagram of the structure of another channel detection device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0057] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0058] In this embodiment, the position and the symbol have the same meaning; the path and the multipath have the same meaning; The meaning of is the same as P in the figure, both represent detection signals; Indicates the number of paths.

[0059] Please refer to Figure 1 , Figure 1 A flow chart of a channel detection method provided by an embodiment of the present invention. The method is applied at the transmitting end and may include:

[0060] S101: Obtain an AFDM signal including a detection signal and a guard interval according to the characteristics of the channel to be detected.

[0061] This embodiment obtains an AFDM (Affine Frequency Division Multiplexing) signal according to the characteristic design of the channel to be detected. The AFDM waveform uses DAFT (Discrete Affine Fourier Transform) to realize the modulation and demodulation of information symbols, which can overcome the double dispersion problem caused by high-speed movement to the channel, and is one of the most promising candidate waveforms in the future 6G wireless communication network. Based on the channel detection method provided in this embodiment, other new waveforms in the delay Doppler domain can also be used, such as orthogonal time frequency space (OTFS) modulation waveform. Therefore, it can be understood that the AFDM signal generally includes the length of the signal sequence, the bandwidth, and the parameters of the DAFT (Discrete Affine Fourier Transform) transformation. The channel characteristics in this embodiment are generally the maximum multipath delay, maximum moving speed, carrier frequency and speed of light that may occur in the channel. The AFDM signal is a communication waveform, and naturally includes data symbols. In this embodiment, the AFDM signal includes a detection signal to achieve integration of the communication waveform and the detection waveform, and further inserts a protection interval to avoid interference between the detection signal and the data symbols.

[0062] Further, in order to obtain the accuracy of the AFDM signal, the above-mentioned obtaining the AFDM signal including the detection signal and the guard interval according to the characteristics of the channel to be detected may include the following steps:

[0063] Step 21: Determine the maximum multipath delay, maximum moving speed and carrier frequency according to the channel to be detected;

[0064] Step 22: Calculate the maximum Doppler frequency shift according to the maximum moving speed, carrier frequency and light speed;

[0065] Step 23: Determine the length, bandwidth and DAFT transformation parameter values ​​of the AFDM signal according to the maximum multipath delay and the maximum Doppler frequency shift, wherein the DAFT transformation parameter values ​​include the first parameter value and the second parameter value ;

[0066] Step 24: Insert the detection signal into the AFDM signal with determined length, bandwidth and parameter values, and insert guard intervals of preset lengths on both sides of the detection signal to obtain the AFDM signal.

[0067] Steps 21 to 23 are the process of determining the length, bandwidth and DAFT transformation parameter values ​​of the AFDM signal, assuming that the maximum possible multipath delay of the measurement channel is , Maximum speed , the carrier frequency is , the speed of light is ,in is an integer delay normalized with respect to the delay resolution. Find the maximum Doppler shift , the specific calculation formula is:

[0068] ;

[0069] According to the maximum multipath delay and the maximum Doppler shift , set the signal bandwidth of the corresponding AFDM sequence and sequence length Correspondingly, the delay resolution of AFDM is , Doppler resolution , according to the delay resolution , Doppler resolution With signal bandwidth and sequence length The relationship between the two requires setting a suitable signal bandwidth. and sequence length The resolution is sufficient to distinguish the maximum multipath delay of the channel and the maximum Doppler shift .according to Calculate the integer part of the normalized maximum Doppler shift , the first parameter value of DAFT transformation is obtained according to the normalized maximum Doppler frequency shift , get the second parameter value according to the sequence length Or you can use the Doppler frequency shift calculation formula Calculate the Doppler frequency shift corresponding to each path, and then take the maximum value as the maximum Doppler frequency shift. represents the true Doppler shift of the ith path, Represents the relative moving speed of the i-th path. The formula normalizes the Doppler shift of each path, where represents the normalized Doppler shift of the ith path, is its integer part, is satisfied The decimal part of Represents the integer part of the normalized maximum Doppler frequency shift. Further obtain the first parameter value of DAFT transformation and the second parameter value .

[0070] Step 24 is a process of determining the symbol position in the AFDM signal. Specifically, in the AFDM sequence of length N, the first position is inserted with the detection signal , in the detection signal The purpose of inserting guard intervals at both ends of the detection signal is to better protect the detection signal from interference from other signals from both sides, and any code element can be inserted in the remaining position. This embodiment does not limit the length of the guard interval. The energy can be based on The formula is calculated, where represents the noise power of the channel to be detected, Represents the signal-to-noise ratio of the detection signal, which is set based on experience. Represents the energy of the detection signal.

[0071] Further, for the communication efficiency of the AFDM signal, the preset length is greater than or equal to the first length, and the calculation formula of the first length is:

[0072] ;

[0073] in, Indicates the first length, represents the integer part of the maximum multipath delay after normalization of the delay resolution, Represents the integer part of the maximum Doppler shift after normalization of the Doppler shift resolution.

[0074] In this embodiment, a guard interval of a preset length is obtained according to a calculation formula of the first length. Generally, the preset length is generally set to the first length.

[0075] S102: Send the AFDM signal to the receiving end through the channel to be detected so that the receiving end obtains the AFDM signal, and performs threshold judgment on the AFDM signal to obtain gain, delay and Doppler frequency shift, and performs Monte Carlo statistical analysis on the gain, delay and Doppler frequency shift to obtain the power delay spectrum and Doppler power spectrum of the channel to be detected.

[0076] When S101 is completed, the AFDM signal can be sent to the receiving end through the channel to be detected, so that the receiving end can perform threshold judgment and statistical analysis based on the received signal to obtain the power delay spectrum and Doppler power spectrum of the detection signal.

[0077] The channel detection method applied to the transmitting end provided by the embodiment of the present invention is applied to obtain an AFDM signal including a detection signal and a protection interval according to the characteristics of the channel to be detected; the AFDM signal is sent to the receiving end through the channel to be detected so that the receiving end obtains the AFDM signal, and the AFDM signal is threshold judged to obtain the gain, delay and Doppler frequency shift, and the gain, delay and Doppler frequency shift are subjected to Monte Carlo statistical analysis to obtain the power delay spectrum and Doppler power spectrum of the channel to be detected. The method uses the AFDM waveform to detect the channel, so that the real-time and accuracy of the channel detection can be guaranteed in high dynamic scenarios; compared with the traditional PN sequence-based and OFDM-based channel detection methods, the method can directly obtain the gain, delay and Doppler frequency shift of the channel, and further obtain the power delay spectrum and Doppler power spectrum of the channel without going through additional processing steps, thereby improving the efficiency of channel detection; and the communication waveform is combined with the detection waveform to realize the integration of the two, and communication and detection are realized together, which saves resources and improves efficiency.

[0078] Please refer to Figure 2 , Figure 2 A flow chart of another channel detection method provided by an embodiment of the present invention. The method is applied at the receiving end and may include:

[0079] S201: receiving an AFDM signal sent by a transmitter through a channel to be detected, where the AFDM signal is an AFDM signal including a detection signal and a guard interval obtained by the transmitter according to characteristics of the channel to be detected.

[0080] In this embodiment, the receiving end receives the AFDM signal sent by the transmitting end through the channel to be detected. The AFDM signal is obtained according to the characteristics of the signal to be detected, and the signal includes a detection signal and a guard interval. Therefore, the AFDM signal between the transmitting end and the receiving end passes through the channel to be detected, and there are a series of operations in the middle, such as signal modulation and channel influence, so it is possible that the signal received by the receiving end is different from the signal sent by the transmitting end.

[0081] S202: Perform threshold judgment on the AFDM signal to obtain gain, delay and Doppler frequency shift, and perform Monte Carlo statistical analysis on the gain, delay and Doppler frequency shift to obtain a power delay spectrum and a Doppler power spectrum of the channel to be detected.

[0082] The receiving end performs threshold judgment on the received signal to determine the gain, delay and Doppler frequency shift of the influencing position; and performs Monte Carlo statistical analysis on the gain, delay and Doppler frequency shift of the influencing position to determine the power delay spectrum and Doppler power spectrum of the channel to be detected.

[0083] Further, for the accuracy of channel detection, the above threshold judgment of the AFDM signal is performed to obtain the gain, delay and Doppler frequency shift, and the Monte Carlo statistical analysis of the gain, delay and Doppler frequency shift is performed to obtain the power delay spectrum and Doppler power spectrum of the channel to be detected, which may include the following steps:

[0084] Step 31: Determine the first parameter value of DAFT transformation using the AFDM signal The positive and negative situation;

[0085] Step 32: If the first parameter value If it is a positive number, the detection signal and the guard interval on the left side of the detection signal are located in the decision area;

[0086] Step 33: When the first parameter value If it is a negative number, the detection signal and the guard interval on the right side of the detection signal are located in the decision area;

[0087] Step 34: Set a decision threshold, and traverse each position in the decision area, and take the position with energy value greater than the decision threshold as the position to be analyzed;

[0088] Step 35: Obtain the time delay and Doppler frequency shift of the path corresponding to the position to be analyzed;

[0089] Step 36: Calculate the gain of the path corresponding to the position to be analyzed;

[0090] Step 37: Perform multiple Monte Carlo statistics on the delay, Doppler frequency shift and gain to obtain the power delay spectrum and Doppler power spectrum of the path corresponding to the position to be analyzed.

[0091] The detection signal will only affect the protection interval on one side. The positive or negative situation of the first parameter determines the affected protection interval, thereby determining the decision area. For the detection signal with protection intervals on both sides, according to the first parameter value The positive or negative condition of determines the protection interval impact side. Specifically, the first parameter value The calculation formula is:

[0092] ;

[0093] in, represents the integer part of the normalized maximum Doppler shift, Indicates the length of the AFDM sequence.

[0094] Since AFDM multiplexes information symbols in the DAFT domain, and there is a one-to-one correspondence between the DAFT domain and the delay-Doppler domain, the decision threshold is set , traverse this decision area, if the energy value is greater than the decision threshold It is considered that there is a path to the location, and the time delay and Doppler shift of the location are obtained.

[0095] The above calculation of the gain of the path corresponding to the position to be analyzed can be derived from the input-output relationship of AFDM to obtain the calculation formula of the gain, where the formula of the input-output relationship of AFDM is:

[0096] ;

[0097] ;

[0098] ;

[0099] Therefore, the calculation formula of gain is derived as follows:

[0100] ;

[0101] Indicates the number of paths; Indicates a detection signal; is a complex factor, ; i is the index of the path, the i-th path; Represents the AFDM signal sent by the transmitter. Indicates the AFDM signal received by the receiving end, represents additive white Gaussian noise, represents the gain of the i-th path, and Both represent custom intermediate variables. represents the path delay of the i-th path.

[0102] When the gains, delays and Doppler frequency shifts corresponding to all positions to be analyzed are obtained, Monte Carlo is used to perform multiple statistics to obtain the power delay spectrum and Doppler power spectrum of the channel to be detected.

[0103] The channel detection method applied to the receiving end provided by the embodiment of the present invention is applied to receive the AFDM signal sent by the transmitting end through the channel to be detected, and the AFDM signal is an AFDM signal including the detection signal and the protection interval obtained by the transmitting end according to the characteristics of the channel to be detected; the AFDM signal is threshold judged to obtain the gain, delay and Doppler frequency shift, and the gain, delay and Doppler frequency shift are subjected to Monte Carlo statistical analysis to obtain the power delay spectrum and Doppler power spectrum of the channel to be detected. The method uses the AFDM waveform to detect the channel, so that the real-time and accuracy of the channel detection can be guaranteed in high dynamic scenarios; compared with the traditional PN sequence-based and OFDM-based channel detection methods, the method can directly obtain the gain, delay and Doppler frequency shift of the channel, and further obtain the power delay spectrum and Doppler power spectrum of the channel without going through additional processing steps, thereby improving the efficiency of channel detection; and the communication waveform is combined with the detection waveform to realize the integration of the two, and realize communication and detection together, saving resources and improving efficiency.

[0104] In order to make the present invention easier to understand, examples are as follows:

[0105] Step 1: Based on the maximum multipath delay and maximum mobile speed of the measured channel, the length and bandwidth of the AFDM sequence and the two parameters of the AFDM basic transform DAFT are designed. and Specifically, this example uses the gsmTUx6c1 channel model, and the parameters are shown in Table 1. From Table 1, it can be obtained that the maximum multipath delay is 5 , set the maximum moving speed to 30m / s, and design the AFDM sequence length , the signal bandwidth is . Assume the carrier frequency , ; then the maximum Doppler shift , the Doppler resolution of the AFDM sequence , then the integer part of the maximum normalized Doppler shift , delay resolution , that is, the maximum normalized delay ,but ,Pick .

[0106] Table 1 gsmTUx6c1 channel model parameters

[0107]

[0108] Step 2: At the transmitting end, a detection signal and a guard interval of corresponding length are inserted into the AFDM sequence to avoid interference between other symbols and the detection signal.

[0109] Step 2.1: The protection interval is ;

[0110] Step 2.2: Design the AFDM sequence, such as Figure 3 , P is the inserted detection signal, and the two sides is the guard interval. In addition to the guard interval In addition, other data will not affect the detection signal P, and any symbol can be inserted, that is, any code element can be inserted in the middle area. Since this example only discusses the channel detection performance, the transmission data is not considered, that is, all filled with 0;

[0111] Step 3: Make a threshold decision on the position related to the received symbol;

[0112] Step 3.1: Figure 4 is the signal received by the receiving end, as shown in Figure 4 It can be seen that the judgment area includes symbols, and each symbol corresponds to 1 time delay and 1 Doppler frequency shift;

[0113] Step 3.2: Set the signal-to-noise ratio of the detection signal P to 40, according to The formula can be used to obtain the inserted detection signal energy The value of Set as , traverse symbols, and judge whether the energy value of each symbol is greater than the threshold If it is greater than, it means there is a path here. The delay and Doppler of the path are determined by this position, and the gain is given by the formula To obtain.

[0114] Step 4: Perform statistical analysis on all symbols greater than the threshold by running Monte Carlo 50,000 times. The power delay spectrum and Doppler power spectrum of the detection channel can be directly obtained. In this example, the power threshold is set to -20dB. Only when the multipath power is greater than -20dB, the path is considered to be a valid path. Then, the Doppler power spectra of all valid paths are counted.

[0115] The following experiment verifies this method. Figure 5 and Figure 6 ,Depend on Figure 5It can be clearly seen that the estimated power delay spectrum is basically consistent with the theoretical expected power delay spectrum, with the horizontal axis representing the delay and the vertical axis representing APDP (average power delay profile). It is worth noting that in the simulation, since the delay is normalized and rounded, although the rounded delay is accurately estimated, there is an inevitable error due to the delay resolution. At the same time, it can be observed that the power of each path is basically consistent with the theoretical value, which shows that this method obtains a relatively accurate power delay spectrum for the gsmTUx6c1 channel. Figure 6 The six paths in the estimated power delay spectrum, the Doppler power spectrum of each path and the theoretical Doppler power spectrum are displayed. According to the channel model parameters, it can be found that these six paths all conform to the Jakes distribution. By directly estimating the Doppler frequency shift of each path in the delay Doppler domain without any additional conversion, the Doppler power spectrum estimated by this method is highly consistent with the theoretical Jakes spectrum. Therefore, judging from the results of the power delay spectrum and the Doppler power spectrum, the channel detection method provided by the present invention performs well and achieves excellent detection effects.

[0116] The following is an introduction to a channel detection device provided in an embodiment of the present invention. The channel detection device described below and the channel detection method described above can be referred to each other.

[0117] Please refer to Figure 7 , Figure 7 A schematic structural diagram of a channel detection device provided in an embodiment of the present invention, which is applied to a transmitting end, may include:

[0118] The AFDM sequence acquisition module 100 is used to obtain an AFDM signal including a detection signal and a guard interval according to the characteristics of the channel to be detected;

[0119] The sending module 200 is used to send the AFDM signal to the receiving end through the channel to be detected so that the receiving end obtains the AFDM signal, and performs threshold judgment on the AFDM signal to obtain gain, delay and Doppler frequency shift, and performs Monte Carlo statistical analysis on the gain, the delay and the Doppler frequency shift to obtain the power delay spectrum and Doppler power spectrum of the channel to be detected.

[0120] Based on the above embodiment, the AFDM sequence obtaining module 100 may include:

[0121] A data determination unit, configured to determine a maximum multipath delay, a maximum moving speed and a carrier frequency according to the channel to be detected;

[0122] A calculation unit, configured to calculate a maximum Doppler frequency shift according to the maximum moving speed, the carrier frequency and the speed of light;

[0123] A sequence determination unit, configured to determine the length and bandwidth of the AFDM sequence and a parameter value of DAFT transformation according to the maximum multipath delay and the maximum Doppler frequency shift, wherein the parameter value of DAFT transformation includes a first parameter value and the second parameter value ;

[0124] The inserting unit is used to insert the detection signal into the AFDM signal with the determined length, bandwidth and parameter value, and insert the guard interval of the preset length on both sides of the detection signal to obtain the AFDM signal.

[0125] Based on the above embodiment, the insertion unit includes:

[0126] The length calculation subunit is used to preset a length greater than or equal to a first length, and the calculation formula of the first length is: ;in, Indicates the first length, represents the integer part of the maximum multipath delay after normalization of the delay resolution, Represents the integer part of the maximum Doppler shift after normalization of the Doppler shift resolution.

[0127] The channel detection device provided by the embodiment of the present invention is applied to the transmitting end, and the AFDM sequence acquisition module 100 is used to obtain the AFDM signal including the detection signal and the protection interval according to the characteristics of the channel to be detected; the sending module 200 is used to send the AFDM signal to the receiving end through the channel to be detected, so that the receiving end obtains the AFDM signal, and threshold judgment is performed on the AFDM signal to obtain the gain, delay and Doppler frequency shift, and the gain, delay and Doppler frequency shift are subjected to Monte Carlo statistical analysis to obtain the power delay spectrum and Doppler power spectrum of the channel to be detected. The method uses the AFDM waveform to detect the channel, so that the real-time and accuracy of the channel detection can be guaranteed in high dynamic scenarios; compared with the traditional PN sequence-based and OFDM-based channel detection methods, the method can directly obtain the gain, delay and Doppler frequency shift of the channel, and further obtain the power delay spectrum and Doppler power spectrum of the channel without going through additional processing steps, thereby improving the efficiency of channel detection; and the communication waveform is combined with the detection waveform to realize the integration of the two, and communication and detection are realized together, which saves resources and improves efficiency.

[0128] Another channel detection device provided by an embodiment of the present invention is introduced below. The channel detection device described below and the channel detection method described above can be referred to each other.

[0129] Please refer to Figure 8 , Figure 8 A schematic structural diagram of another channel detection device provided by an embodiment of the present invention, which is applied to a receiving end, may include:

[0130] The receiving module 300 is used to receive an AFDM signal sent by a transmitting end through a channel to be detected, wherein the AFDM signal is the AFDM signal including a detection signal and a guard interval obtained by the transmitting end according to the characteristics of the channel to be detected;

[0131] The decision analysis module 400 is used to perform threshold decision on the AFDM signal to obtain gain, delay and Doppler frequency shift, and perform Monte Carlo statistical analysis on the gain, delay and Doppler frequency shift to obtain the power delay spectrum and Doppler power spectrum of the channel to be detected.

[0132] Based on the above embodiment, the decision analysis module 400 may include:

[0133] A positive and negative determination unit, used to determine the first parameter value of the DAFT transformation through the AFDM signal The positive and negative situation;

[0134] The first decision area determination unit is used to determine the first parameter value if is a positive number, then the detection signal and the left guard interval of the detection signal are located in the decision area;

[0135] The second decision area determination unit is used to determine the first parameter value when is a negative number, the detection signal and the location of the right guard interval of the detection signal are the decision area;

[0136] A decision unit, used to set a decision threshold, and traverse each position of the decision area, and take the position with energy value greater than the decision threshold as the position to be analyzed;

[0137] An acquisition unit, used to acquire the time delay and Doppler frequency shift of the path corresponding to the position to be analyzed;

[0138] A gain calculation unit, used to calculate the gain of the path corresponding to the position to be analyzed;

[0139] A statistical unit is used to perform multiple Monte Carlo statistics on the time delay, the Doppler frequency shift and the gain to obtain the power delay spectrum and the Doppler power spectrum of the path corresponding to the position to be analyzed.

[0140] Based on the above embodiment, the first parameter value in the positive and negative determination unit The calculation formula is: ;in, represents the integer part of the normalized maximum Doppler shift, Indicates the length of the AFDM sequence.

[0141] The channel detection device provided by the embodiment of the present invention is applied to the receiving end, and is used to receive the AFDM signal sent by the transmitting end through the channel to be detected through the receiving module 300, and the AFDM signal is an AFDM signal including the detection signal and the protection interval obtained by the transmitting end according to the characteristics of the channel to be detected; the decision analysis module 400 is used to perform threshold decision on the AFDM signal to obtain the gain, delay and Doppler frequency shift, and perform Monte Carlo statistical analysis on the gain, delay and Doppler frequency shift to obtain the power delay spectrum and Doppler power spectrum of the channel to be detected. The method uses the AFDM waveform to detect the channel, so that the real-time and accuracy of the channel detection can be guaranteed in high dynamic scenarios; compared with the traditional PN sequence-based and OFDM-based channel detection methods, the method can directly obtain the gain, delay and Doppler frequency shift of the channel, and further obtain the power delay spectrum and Doppler power spectrum of the channel without going through additional processing steps, thereby improving the efficiency of channel detection; and the communication waveform is combined with the detection waveform to realize the integration of the two, and realize communication and detection together, saving resources and improving efficiency.

[0142] The computer-readable storage medium provided in an embodiment of the present invention is introduced below. The computer-readable storage medium described below and the channel detection method described above can be referred to each other.

[0143] The present invention also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned channel detection method are implemented.

[0144] The computer-readable storage medium may include: a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and other media that can store program codes.

[0145] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0146] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0147] Finally, it should be noted that, in this article, relationships such as first and second, etc. are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variations are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0148] The above is a detailed introduction to a channel detection method, device and computer-readable storage medium provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A channel detection method, characterized in that: Applied to the sending end, including: Obtaining an AFDM signal including a detection signal and a guard interval according to the characteristics of the channel to be detected; The AFDM signal is sent to the receiving end through the channel to be detected so that the receiving end obtains the AFDM signal, and threshold judgment is performed on the AFDM signal to obtain gain, delay and Doppler frequency shift, and Monte Carlo statistical analysis is performed on the gain, delay and Doppler frequency shift to obtain the power delay spectrum and Doppler power spectrum of the channel to be detected.

2. The channel detection method according to claim 1, characterized in that: The step of obtaining an AFDM signal including a detection signal and a guard interval according to the characteristics of the channel to be detected includes: Determine the maximum multipath delay, the maximum moving speed and the carrier frequency according to the channel to be detected; The maximum Doppler shift is calculated according to the maximum moving speed, the carrier frequency and the speed of light; The length, bandwidth and DAFT conversion parameter values ​​of the AFDM signal are determined according to the maximum multipath delay and the maximum Doppler frequency shift, wherein the DAFT conversion parameter values ​​include a first parameter value and the second parameter value ; The detection signal is inserted into the AFDM signal with the determined length, bandwidth and parameter value, and the guard interval of the preset length is respectively inserted on both sides of the detection signal to obtain the AFDM signal.

3. The channel detection method according to claim 2, characterized in that: The preset length is greater than or equal to the first length, and the calculation formula of the first length is: ； in, Indicates the first length, represents the integer part of the maximum multipath delay after normalization of the delay resolution, Represents the integer part of the maximum Doppler shift after normalization of the Doppler shift resolution.

4. A channel detection method, characterized in that: Applied to the receiving end, including: Receiving an AFDM signal sent by a transmitting end through a channel to be detected, wherein the AFDM signal is the AFDM signal including a detection signal and a guard interval obtained by the transmitting end according to the characteristics of the channel to be detected; Threshold decision is performed on the AFDM signal to obtain gain, delay and Doppler frequency shift, and Monte Carlo statistical analysis is performed on the gain, delay and Doppler frequency shift to obtain a power delay spectrum and a Doppler power spectrum of the channel to be detected.

5. The channel detection method according to claim 4, characterized in that: The step of performing threshold judgment on the AFDM signal to obtain gain, delay and Doppler frequency shift, and performing Monte Carlo statistical analysis on the gain, delay and Doppler frequency shift to obtain a power delay spectrum and a Doppler power spectrum of the channel to be detected includes: Determine a first parameter value of DAFT transformation by using the AFDM signal The positive and negative situation; If the first parameter value is a positive number, then the detection signal and the left guard interval of the detection signal are located in the decision area; When the first parameter value is a negative number, the detection signal and the location of the right guard interval of the detection signal are the decision area; Setting a decision threshold, and traversing each position of the decision area, and taking the position whose energy value is greater than the decision threshold as the position to be analyzed; Obtaining the time delay and Doppler frequency shift of the path corresponding to the position to be analyzed; Calculating the gain of the path corresponding to the position to be analyzed; Monte Carlo statistics are performed multiple times on the time delay, the Doppler frequency shift and the gain to obtain the power delay spectrum and the Doppler power spectrum of the path corresponding to the position to be analyzed.

6. The channel detection method according to claim 5, characterized in that: Determining a first parameter value of DAFT transformation by using the AFDM signal The positive and negative conditions include: The first parameter value The calculation formula is: ； in, represents the integer part of the normalized maximum Doppler shift, Indicates the length of the AFDM sequence.

7. A channel detection device, characterized in that: Applied to the sending end, including: An AFDM sequence acquisition module, used for obtaining an AFDM signal including a detection signal and a guard interval according to the characteristics of the channel to be detected; The sending module is used to send the AFDM signal to the receiving end through the channel to be detected so that the receiving end obtains the AFDM signal, and performs threshold judgment on the AFDM signal to obtain gain, delay and Doppler frequency shift, and performs Monte Carlo statistical analysis on the gain, the delay and the Doppler frequency shift to obtain the power delay spectrum and Doppler power spectrum of the channel to be detected.

8. A channel detection device, characterized in that: Applied to the receiving end, including: A receiving module, used for receiving an AFDM signal sent by a transmitting end through a channel to be detected, wherein the AFDM signal is the AFDM signal including a detection signal and a guard interval obtained by the transmitting end according to the characteristics of the channel to be detected; The decision analysis module is used to perform threshold decision on the AFDM signal to obtain gain, delay and Doppler frequency shift, and perform Monte Carlo statistical analysis on the gain, delay and Doppler frequency shift to obtain the power delay spectrum and Doppler power spectrum of the channel to be detected.

9. The channel detection device according to claim 8, characterized in that: The judgment analysis module comprises: A positive and negative determination unit, used to determine the first parameter value of the DAFT transformation through the AFDM signal The positive and negative situation; The first decision area determination unit is used to determine the first parameter value if is a positive number, then the detection signal and the left guard interval of the detection signal are located in the decision area; The second decision area determination unit is used to determine the first parameter value when is a negative number, the detection signal and the location of the right guard interval of the detection signal are the decision area; A decision unit, used to set a decision threshold, and traverse each position of the decision area, and take the position with energy value greater than the decision threshold as the position to be analyzed; An acquisition unit, used to acquire the time delay and Doppler frequency shift of the path corresponding to the position to be analyzed; A gain calculation unit, used to calculate the gain of the path corresponding to the position to be analyzed; A statistical unit is used to perform multiple Monte Carlo statistics on the time delay, the Doppler frequency shift and the gain to obtain the power delay spectrum and the Doppler power spectrum of the path corresponding to the position to be analyzed.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, and when the computer-executable instructions are loaded and executed by a processor, the channel detection method according to any one of claims 1 to 6 is implemented.

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