Multi-antenna channel calibration and monitoring method of crossed interconnection double-array-plane structure

Abstract

The invention relates to a multi-antenna channel calibration and monitoring method for a cross-interconnected double-array-plane structure, which comprises the following steps of: calibrating and monitoring antenna array planes of the cross-interconnected double-array-plane structure and transmitting or receiving channels of a signal processing unit; the method for calibrating the transmitting channel comprises the following steps of: transmitting a transmitting channel local calibration sequence to an antenna channel of which an antenna array surface is connected with a signal processing unit, and transmitting the transmitting channel local calibration sequence to a calibration channel of the signal processing unit to obtain a transmitting channel calibration receiving sequence; the signal processing unit calculates a transmitting channel calibration coefficient and a monitoring coefficient according to the transmitting channel calibration receiving sequence and the local calibration sequence; the signal processing unit transmits the calibration coefficient and the monitoring coefficient of the transmitting channel, connected with other signal processing units, of the antenna array plane to the other signal processing units through the data transmission line; and the signal processing unit reports and indicates the channel fault problem according to the monitoring coefficient, and compensates the transmitted data according to the calibration coefficient of the transmitting channel, connected with the signal processing unit, of the antenna array plane.

Description

Technical Field

[0001] The present invention relates to the field of communication technologies, and more specifically, to a method for calibrating and monitoring multi-antenna channels with a cross-connected dual-array structure. Background Art

[0002] In high-reliability application scenarios, in order to improve the reliability of communication systems and solve the problem of communication interruption caused by equipment failures, multi-antenna devices with a cross-connected dual-array structure have been applied in many fields. For example, communication base stations used for railway train dispatching adopt a cross-connected dual-array structure, that is, two antenna arrays and two signal processing units are used. The transceiver channels of each antenna array are divided into two parts and are respectively connected to the two signal processing units. When a certain antenna array or signal processing unit fails, the other antenna array or signal processing unit can still continue to complete communication, thereby reducing the probability of communication interruption caused by equipment failures.

[0003] In a multi-antenna device with a cross-connected dual-array structure, when the number of antenna channels of each antenna array is large, it is often necessary to calibrate the amplitude, phase, and time delay of the receiving and transmitting channels of the two antenna arrays respectively, so that the receiving and transmitting channels of the two antenna arrays have the same amplitude, phase, and time delay characteristics, thereby avoiding the problem of reducing communication performance due to random differences in the characteristics of each channel. In addition, calibrating the amplitude, phase, and time delay of the transceiver channels of the two antenna arrays respectively can enable each antenna array to support advanced signal processing algorithms such as beamforming and improve the information transmission rate of the communication system.

[0004] The limitations of existing antenna array channel calibration methods mainly include the following points: First, existing antenna array channel calibration methods mainly focus on the calibration between multiple antenna channels on a single antenna array, and rarely consider the calibration problem of multi-antenna channels with a cross-connected dual-array structure; Second, existing antenna array channel calibration methods often focus on the amplitude and phase characteristics of antenna channels, and rarely consider calibrating the time delay characteristics of each channel; Third, existing antenna array channel calibration methods often only consider the calibration implementation of channel characteristics alone, or only consider the monitoring of channel failures alone, and rarely consider using calibration sequences to simultaneously achieve the calibration of channel characteristics and the monitoring of channel failures. Summary of the Invention

[0005] The present invention aims to overcome at least one defect (shortcoming) of the above-mentioned prior art, and provides a method for calibrating and monitoring multi-antenna channels with a cross-connected dual-array structure, which is used to realize the monitoring and calibration of the multi-antenna transceiver channels with a cross-connected dual-array structure.

[0006] The technical solution adopted by the present invention is a method for calibrating and monitoring multiple antenna channels with a cross-connected dual-array structure. The method includes: calibrating and monitoring the transmission channels of several antenna arrays and several signal processing units with a cross-connected dual-array structure. The steps are as follows:

[0007] S11: Transmit the local calibration sequence of the transmission channel to the antenna channels connected to different signal processing units of the antenna array respectively, and transmit it to the calibration channel of one of the signal processing units to obtain the calibration received sequence of the transmission channel;

[0008] S12: The one signal processing unit calculates the calibration coefficient and monitoring coefficient of the transmission channels connected to each signal processing unit of the antenna array according to the calibration received sequence of the transmission channel and the local calibration sequence of the transmission channel;

[0009] S13: The one signal processing unit transmits the calibration coefficient and monitoring coefficient of the transmission channels connected to other signal processing units of the antenna array to other signal processing units through a data transmission line;

[0010] S14: Each signal processing unit reports and indicates channel fault problems according to the monitoring coefficient, and compensates the transmitted data according to the calibration coefficient of the transmission channels connected to each signal processing unit of the antenna array;

[0011] The method further includes: calibrating and monitoring the receiving channels of several antenna arrays and several signal processing units with a cross-connected dual-array structure. The steps are as follows:

[0012] S21: The signal processing unit sends the local calibration sequence of the receiving channel through the calibration channel. After passing through the coupler in the antenna array, the signal processing unit obtains the calibration received sequence of the receiving channel connected to the antenna array and the signal processing unit;

[0013] S22: The signal processing unit calculates the calibration coefficient and monitoring coefficient of the receiving channel connected to the antenna array and the signal processing unit according to the calibration received sequence of the receiving channel connected to the antenna array and the signal processing unit and the local calibration sequence of the receiving channel;

[0014] S23: The signal processing unit reports and indicates channel fault problems according to the monitoring coefficient, and compensates the received data according to the calibration coefficient of the receiving channel connected to the corresponding signal processing unit of the antenna array.

[0015] In the present invention, by using a calibration sequence to calculate the calibration coefficients of each antenna channel in each antenna array in the cross-connected dual-array structure, and compensating the received and transmitted data according to the calibration coefficients, the multi-antenna channel calibration problem of the cross-connected dual-array structure is effectively solved; moreover, a monitoring coefficient is calculated by using the calibration sequence to monitor the antenna channel, so as to realize reporting and indicating the channel fault problem according to the monitoring coefficient, and real-time monitoring, fault detection and feedback of the wireless communication channel can be achieved, thereby improving the reliability and transmission performance of the communication system.

[0016] Preferably, the local calibration sequence of the transmit channel is obtained by performing OFDM (Orthogonal Frequency Division Multiplexing) modulation on a pseudo-random sequence after constellation mapping in a frequency-division multiplexing manner to generate an OFDM symbol with a cyclic prefix; or by using time-division multiplexing, or by using time / frequency-division multiplexing to perform OFDM modulation to generate multiple OFDM symbols with cyclic prefixes.

[0017] Preferably, the local calibration sequence of the receive channel is obtained by performing OFDM modulation on a pseudo-random sequence after constellation mapping to generate an OFDM symbol with a cyclic prefix.

[0018] Preferably, the channel calibration coefficient includes a delay calibration coefficient, and the delay calibration coefficient includes a transmit-channel delay calibration coefficient and a receive-channel delay calibration coefficient; wherein,

[0019] The calculation method of the transmit-channel delay calibration coefficient includes the following steps:

[0020] S311: Remove the cyclic prefix from the calibration receive sequence and perform a fast Fourier transform to obtain a frequency-domain receive sequence, and estimate the frequency-domain channel according to the frequency-domain receive sequence and the local frequency-domain sequence;

[0021] S312: Calculate the transmit-channel correlation value according to the frequency-domain channel, and calculate the initial delay coefficient of each transmit channel according to the calculated transmit-channel correlation value;

[0022] S313: Determine the maximum delay value according to the initial delay coefficients of each transmit channel, then set the maximum delay to zero, and calculate the transmit-channel delay calibration coefficient;

[0023] The calculation method of the receive-channel delay calibration coefficient includes the following steps:

[0024] S321: Remove the cyclic prefix from the calibrated received sequence and perform a fast Fourier transform to obtain the frequency-domain received sequence, and estimate the frequency-domain channel based on the frequency-domain received sequence and the local frequency-domain sequence;

[0025] S322: Calculate the received channel correlation value based on the frequency-domain channel, and calculate the initial delay coefficient of each receiving channel based on the calculated received channel correlation value. The initial delay coefficient of each channel is the received channel delay calibration coefficient.

[0026] In this application, first, by removing the cyclic prefix and performing a fast Fourier transform, the received signal is converted to the frequency domain, which can effectively eliminate the time-domain interference of the signal and make the frequency-domain signal easier to process and analyze; then, the frequency-domain channel is estimated, and the correlation value is calculated by using the frequency-domain channel correlation information, providing a preliminary delay estimate for delay calibration. This preliminary estimation result can help the cross-interconnected dual-array structure determine the initial delay coefficient of each transmitting and receiving channel; finally, for the transmitting channel, the maximum delay value is determined according to the initial delay coefficient of each channel and set to zero, thereby obtaining the delay calibration coefficient of each transmitting channel; for the receiving channel, the initial delay coefficient of each channel is the delay calibration coefficient. This process can achieve precise delay calibration and ensure the synchronization and accuracy of the signals of each channel during transmission.

[0027] Preferably, in the step S312, the calculation formula for the transmitted channel correlation value is:

[0028]

[0029] Where represents the correlation value of the transmitting channel i, I i represents the index set mapped by the local frequency-domain calibration sequence of the transmitting channel i in the OFDM subcarriers. The elements of I i are arranged in ascending order to form an arithmetic sequence with a common difference of K1. I i (j) represents the j-th element of the set I i , is the frequency-domain channel related to the transmitting channel i, represents the subcarrier index I i (j) at the frequency-domain channel, conj(x) represents taking the conjugate of the complex number x, N L is the number of subcarriers mapped by the local frequency-domain calibration sequence of the transmitting channel in the OFDM subcarriers, that is, the number of elements of the set I i ;

[0030] The calculation formula for the initial delay coefficient of the transmitting channel is:

[0031]

[0032] Among them, represents the initial delay coefficient of each transmission channel, angle(x) represents taking the phase of x, and N FFT represents the total number of subcarriers of the OFDM signal.

[0033] Preferably, in the step S322, the calculation formula of the correlation value of the receiving channel is:

[0034]

[0035] Among them, represents the correlation value of the receiving channel i, is the frequency-domain channel related to the receiving channel i, represents the frequency-domain channel at the subcarrier index j, H L is the number of elements of, and K2 is a preset positive integer.

[0036] The calculation formula of the initial delay coefficient of the receiving channel is:

[0037]

[0038] Among them, represents the initial delay coefficient of each receiving channel; angle(x) represents taking the phase of x, and N FFT represents the total number of subcarriers of the OFDM signal.

[0039] Preferably, the calibration coefficient further includes a phase calibration coefficient, and the phase calibration coefficient includes a transmission channel phase calibration coefficient and a receiving channel phase calibration coefficient; among them,

[0040] The calculation method of the transmission channel phase calibration coefficient includes the following steps:

[0041] S411: Calculate the initial phase of the transmission channel, and calculate the initial phase of the transmission channel according to the frequency-domain channel related to the transmission channel i

[0042] S412: Adjust the initial phase of the transmission channel, and adjust the initial phase of the transmission channel to Among them is the delay calibration coefficient of the transmission channel i;

[0043] S413: Process each element after adjusting the initial phase of the transmission channel. If then Among them is The j-th element of;

[0044] S414: For the result obtained by processing in step S413 Take the average value of all elements of to obtain the phase calibration coefficient of the transmission channel;

[0045] The calculation method of the phase calibration coefficient of the receiving channel includes the following steps:

[0046] S421: Calculate the initial phase of the receiving channel, and calculate the initial phase of the receiving channel according to the frequency-domain channel related to receiving channel i Calculate the initial phase of the receiving channel

[0047] S422: Adjust the initial phase, and adjust the initial phase of the receiving channel to Where Is the delay calibration coefficient of receiving channel i, and I is a positive integer ranging from 1 to H L ;

[0048] S423: Process each element after adjusting the initial phase of the receiving channel. If Then Where Is The j-th element of;

[0049] S424: Take the average value of all elements of the result obtained by processing in step S423 to obtain the phase calibration coefficient of the receiving channel. ;

[0050] In this application, by calculating the initial phase of the frequency-domain channel, the system can obtain key parameters related to the phase change in the signal propagation process. Phase is an important factor affecting signal quality and transmission. Accurate phase estimation can significantly improve the signal demodulation effect. By performing related operations such as taking the modulus, adjusting, and taking the average value on the initial phase, the phase deviation can be effectively corrected and a stable phase calibration coefficient can be obtained, thereby eliminating the influence caused by phase mismatch, improving communication quality, and reducing the bit error rate.

[0051] Preferably, the calibration coefficient further includes an amplitude calibration coefficient, and the calculation method of the amplitude calibration coefficient is: calculate the average power of the frequency-domain received sequence, and perform normalization and square-root processing on the average power of each channel with respect to the average power of the first channel, so as to obtain the amplitude calibration coefficient.

[0052] By obtaining the amplitude calibration coefficient through the above steps, the amplitude mismatch caused by channel hardware differences is effectively corrected, thereby optimizing the amplitude of the received signal and reducing the errors and distortions caused by amplitude mismatch.

[0053] Preferably, the calculation method of the monitoring coefficient includes: calculating the channel average amplitude according to the estimated frequency-domain channel, then constructing an initial frequency-domain channel based on the channel average amplitude, and then calculating the monitoring coefficient according to the initial frequency-domain channel.

[0054] In this application, in addition to calculating the calibration coefficient and using the calibration coefficient to calibrate the transmitting channel and the receiving channel, a monitoring coefficient is also calculated to monitor and feedback the channel quality characteristics in real time. This not only improves the signal quality of the wireless communication system, but also enhances the system's adaptability to the dynamic changes of the channel affected by factors such as temperature, ensuring the efficiency and stability in the communication process, and effectively reducing the bit error rate and packet loss rate.

[0055] Preferably, the calculation formula for calculating the monitoring coefficient according to the initial frequency-domain channel is:

[0056]

[0057] where s i represents the monitoring coefficient of the i-th transmitting or receiving channel; represents the initial frequency-domain channel of the i-th transmitting or receiving channel constructed; H i represents the estimated frequency-domain channel of the i-th transmitting or receiving channel.

[0058] Preferably, within a given time period, the channel is measured by transmitting the local calibration sequence multiple times, and the average values of the calibration coefficients and monitoring coefficients obtained from multiple measurements are taken respectively. The calibration coefficients include the delay calibration coefficient, the phase calibration coefficient, and the amplitude calibration coefficient, so as to obtain the final calibration coefficient and monitoring coefficient.

[0059] In this application, by adopting the method of estimating the delay calibration coefficient, the phase calibration coefficient, the amplitude calibration coefficient, and the monitoring coefficient multiple times and taking the average value of the multiple estimation results, the influence of factors such as channel noise is reduced, and the estimation accuracy of the calibration coefficient is improved, thereby enhancing the reliability and transmission performance of the communication system.

[0060] Compared with the prior art, the beneficial effects of the present invention are:

[0061] This application focuses on the calibration problem of multi-antenna channels with a cross-connected dual-array structure, and provides a method for calibrating and monitoring multi-antenna channels with a cross-connected dual-array structure. By using the calibration channels to receive and transmit calibration sequences, the amplitude, phase, and time delay of the antenna channels of each of the two antenna arrays are estimated, and the received and transmitted data are compensated to achieve the calibration of the antenna channels of each of the two antenna arrays. Moreover, the parameters for calibrating the antenna transceiver channels in the present invention are more comprehensive (including amplitude, phase, time delay, etc.), which can reduce the distortion of the transmitted and received signals and enable the antenna array to support higher-order signal processing schemes, such as beamforming, etc. In addition, based on the calibration signal, the present invention can also achieve the monitoring of the antenna transceiver channels. By estimating the signal-to-noise ratio of the antenna channels as the channel monitoring coefficient, it is used to report and indicate channel fault problems. In summary, in the field of calibrating and monitoring multi-antenna channels with a cross-connected dual-array structure, the present invention is expected to have high application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 FIG. is a schematic flow chart for calibrating and monitoring the transmission channels of several antenna arrays and several signal processing units with a cross-connected dual-array structure provided by the present invention.

[0063] Figure 2 FIG. is a schematic flow chart for calibrating and monitoring the reception channels of several antenna arrays and several signal processing units with a cross-connected dual-array structure provided by the present invention.

[0064] Figure 3 FIG. is a schematic diagram of a cross-connected dual-array structure provided by the present invention.

[0065] Figure 4 FIG. is a schematic flow chart for calibrating and monitoring the transmission channels connected between the first antenna array, the first signal processing unit, and the second signal processing unit provided by the present invention.

[0066] Figure 5 FIG. is a schematic diagram of three ways to generate the local calibration sequence of the transmission channel provided by the present invention.

[0067] Figure 6 FIG. is a schematic flow chart for calibrating and monitoring the reception channels connected between the first antenna array, the first signal processing unit, and the second signal processing unit provided by the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0068] The drawings of the present invention are only for illustrative purposes and should not be construed as a limitation of the present invention. To better illustrate the following embodiments, some components in the drawings will be omitted, enlarged, or reduced, and do not represent the dimensions of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0069] Embodiment 1

[0070] This embodiment provides a method for calibrating and monitoring multi-antenna channels with a cross-connected dual-array structure. The method includes: calibrating and monitoring the transmission channels of several antenna arrays and several signal processing units with a cross-connected dual-array structure, as Figure 1 shown, and its steps are as follows:

[0071] S11: Transmit local calibration sequences for the transmission channels of the antenna arrays connected to different signal processing units respectively, and transmit them to the calibration channel of one of the signal processing units to obtain the transmission channel calibration received sequences;

[0072] S12: The one signal processing unit calculates the calibration coefficients and monitoring coefficients of the transmission channels of this antenna array connected to each signal processing unit according to the transmission channel calibration received sequences and the local calibration sequences of the transmission channels;

[0073] S13: The one signal processing unit transmits the calibration coefficients and monitoring coefficients of the transmission channels of this antenna array connected to other signal processing units to other signal processing units through a data transmission line;

[0074] S14: Each signal processing unit reports and indicates channel fault problems according to the monitoring coefficients, and compensates the transmitted data according to the calibration coefficients of the transmission channels of this antenna array connected to each signal processing unit;

[0075] The method further includes: calibrating and monitoring the receiving channels of several antenna arrays and several signal processing units with a cross-connected dual-array structure, as Figure 2 shown, and its steps are as follows:

[0076] S21: The signal processing unit sends the local calibration sequence for the receiving channel through the calibration channel. After passing through the coupler in the antenna array, the signal processing unit obtains the receiving channel calibration received sequence of the antenna array connected to this signal processing unit;

[0077] S22: The signal processing unit calculates the calibration coefficients and monitoring coefficients of the receiving channel of the antenna array connected to this signal processing unit according to the receiving channel calibration received sequence of the antenna array connected to this signal processing unit and the local calibration sequence of the receiving channel;

[0078] S23: The signal processing unit reports and indicates channel fault problems according to the monitoring coefficients, and compensates the received data according to the calibration coefficients of the receiving channels of the antenna array connected to the corresponding signal processing unit.

[0079] Specifically, as Figure 3As shown, in this embodiment, a cross-connected dual array structure is provided, and its structure includes: a first antenna array, a second antenna array, a first signal processing unit, and a second signal processing unit; where

[0080] The M channels A1, A2, …, A of the first antenna array M are connected to the first signal processing unit, and the other N - M channels B of the first antenna array M+1 , B M+2 , …, B N are connected to the second signal processing unit;

[0081] The M channels B1, B2, …, B of the second antenna array M are connected to the second signal processing unit, and the other N - M channels A of the second antenna array M+1 , A M+2 , …, A N are connected to the first signal processing unit; where N represents the total number of channels of the antenna array;

[0082] The antenna calibration channel A of the first antenna array c is connected to the first signal processing unit; the antenna calibration channel B of the second antenna array c is connected to the second signal processing unit;

[0083] The first signal processing unit is connected to the second signal processing unit through a data transmission line.

[0084] Preferably, based on the above-mentioned cross-connected dual array structure, this embodiment provides a multi-antenna channel calibration and monitoring method for the cross-connected dual array structure, and implements the following calibration and monitoring tasks:

[0085] Task ① Calibration and monitoring of the transmission channels connected between the first antenna array and the first signal processing unit and the second signal processing unit;

[0086] Task ② Calibration and monitoring of the receiving channels connected between the first antenna array and the first signal processing unit and the second signal processing unit;

[0087] Task ③ Calibration and monitoring of the transmission channels connected between the second antenna array and the first signal processing unit and the second signal processing unit;

[0088] Task ④ Calibration and monitoring of the receiving channels connected between the second antenna array and the first signal processing unit and the second signal processing unit.

[0089] Preferably, for Task ①, its process schematic diagram is as Figure 4 shown, and it includes the following steps:

[0090] Step S101: The channels A1, A2, …, A M and B M+1 , B M+2 , …, B N connected between the first antenna array and the first signal processing unit and the second signal processing unit respectively send the local calibration sequences of the transmitting channels and After passing through the couplers and combiners in the first antenna array, they are transmitted to the calibration channels of the first signal processing unit to obtain the calibration received sequences of the transmitting channels and

[0091] Step S102: The first signal processing unit calculates the calibration coefficients of the channels A1, A2, …, A connected between the first antenna array and the first signal processing unit according to the calibration received sequences of the transmitting channels and the local calibration sequences of the transmitting channels, including: phase calibration coefficients M , delay calibration coefficients , amplitude calibration coefficients and monitoring coefficients

[0092] The first signal processing unit calculates the calibration coefficients of the channels B connected between the first antenna array and the second signal processing unit according to the calibration received sequences of the transmitting channels and the local calibration sequences of the transmitting channels, including: phase calibration coefficients M+1 , B, B M+2 , …, B N , delay calibration coefficients , amplitude calibration coefficients and monitoring coefficients

[0093] Step S103: The first signal processing unit transmits the calibration coefficients of the transmitting channels connected between the first antenna array and the second signal processing unit and the monitoring coefficients to the second signal processing unit through the data transmission line;

[0094] Step S104: The first signal processing unit compensates the data transmitted through the channels A1, A2, …, A connected between the first antenna array and the first signal processing unit respectively according to the calibration coefficients of the transmitting channels; and monitors and feeds back the characteristics of the transmitting channels according to the monitoring coefficients M , A

[0095] ​​The second signal processing unit compensates the transmitted data according to the transmission channel calibration coefficients of the first antenna array surface connected to the second signal processing unit for channels B M+1 , B M+2 , …, B N respectively; and monitors and feeds back the characteristics of the transmission channel according to the monitoring coefficients .

[0096] Preferably, in the step S101, the generation methods of the local calibration sequences and of the transmission channels optionally include the following three, but are not limited to the following three generation methods:

[0097] Method 1: Generate the local calibration sequences and

[0098] by using the frequency division multiplexing method. Let the total number of subcarriers of the OFDM (Orthogonal Frequency Division Multiplexing) signal be N FFT , and the length of the CP (Cyclic Prefix) be N CP . First, generate the frequency-domain sequences and of the local calibration sequences and Since the frequency division multiplexing method is used, let N L be the number of subcarriers mapped by the local frequency-domain calibration sequence of the transmission channel in the OFDM subcarriers. Therefore, there is where represents taking the integer part of N FFT / N. The subcarrier indices occupied by the non-zero elements of the frequency-domain sequence are The subcarrier indices occupied by the non-zero elements of the frequency-domain sequence are After determining the subcarrier indices of the non-zero elements of the frequency-domain sequence, the non-zero elements are generated by modulating a pseudo-random sequence through BPSK (Binary Phase Shift Keying), and then the frequency-domain sequences and

[0099] The frequency-domain sequences and are respectively subjected to N FFT -point IFFT transformation to obtain time-domain sequences. After adding CP to each time-domain sequence, the local calibration sequences and

[0100] As shown in Figure 5 (a), a schematic diagram of generating the local calibration sequence of the transmit channel by using frequency division multiplexing is shown. When N FFT = 16, M = 2, and N = 4, the non-zero element indices of the frequency-domain sequence are The non-zero element indices of the frequency-domain sequence are The non-zero element indices of the frequency-domain sequence are The non-zero element indices of the frequency-domain sequence are

[0101] Method 2: Generating the local calibration sequence by using time division multiplexing and

[0102] First, generate the frequency-domain sequences and of and Since the time division multiplexing method is adopted, that is, the local frequency-domain calibration sequence of the transmit channel is mapped to each subcarrier. Therefore, the number of non-zero elements of each frequency-domain sequence, that is, the total number of subcarriers of the OFDM signal is N FFT , and the subcarrier indices of the non-zero elements of the frequency-domain sequence are all where i = 1, 2,..., M, j = M + 1, M + 2,..., N; after determining the subcarrier indices of the non-zero elements of the frequency-domain sequence, its non-zero elements are generated by modulating a pseudo-random sequence through BPSK, and then the frequency-domain sequences and

[0103] The frequency-domain sequences and are respectively subjected to N FFT -point IFFT transformation to obtain time-domain sequences. After adding CP to each time-domain sequence, the local calibration sequences and

[0104] As shown in Figure 5 (b), a schematic diagram of generating the local calibration sequence of the transmit channel by using time division multiplexing is shown. When N FFT = 16, M = 2, and N = 4, the non-zero element indices of the frequency-domain sequence are all {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}.

[0105] Method 3: Generating local calibration sequences using time-frequency division multiplexing and

[0106] First, generate local calibration sequences and in the frequency domain and Since time-frequency division multiplexing is adopted, let the frequency-domain sequence occupy OFDM symbol 1, and frequency division multiplexing is used. Therefore, the number of non-zero elements of each frequency-domain sequence is The subcarrier indices occupied by the non-zero elements of the frequency-domain sequence are Let the frequency-domain sequence occupy OFDM symbol 2, and frequency division multiplexing is used. Therefore, the number of non-zero elements of each frequency-domain sequence is The subcarrier indices occupied by the non-zero elements of the frequency-domain sequence are After determining the subcarrier indices of the non-zero elements of the frequency-domain sequence, its non-zero elements are generated by modulating a pseudo-random sequence through BPSK. Optionally, it can also be generated by modulating a pseudo-random sequence + QPSK, or by constructing other sequences + a certain QAM modulation, so as to obtain the frequency-domain sequences and

[0107] The frequency-domain sequences and are respectively subjected to an N FFT point IFFT transform to obtain time-domain sequences. After adding CP to each time-domain sequence, local calibration sequences and

[0108] As shown in Figure 5 (c), it shows a schematic diagram of generating the local calibration sequence of the transmit channel using time division multiplexing, where when N FFT = 16, M = 2, N = 4, the non-zero element indices of the frequency-domain sequence are The non-zero element indices of the frequency-domain sequence are

[0109] Preferably, in the step S102, if the local calibration sequence of the transmit channel is generated using frequency division multiplexing according to Method 1, the calculation method of the calibration coefficient is as follows:

[0110] For the delay calibration coefficient, in this embodiment, taking the delay calibration coefficient of channel A1 For example, its calculation method includes the following steps:

[0111] S311: Calibrate the received sequence for the transmission channel Remove the cyclic prefix and perform FFT (Fast Fourier Transform) to obtain the frequency-domain received sequence of the transmission channel And based on the frequency-domain received sequence of the transmission channel And the local frequency-domain sequence of the transmission channel Estimate the frequency-domain channel, where the frequency-domain channel formula is:

[0112]

[0113] Wherein, represents the frequency-domain channel of the transmission channel; represents the frequency-domain received sequence of the transmission channel; represents the local frequency-domain sequence of the transmission channel; represents taking the conjugate of each element of

[0114] S312: Calculate the correlation value of the transmission channel according to the frequency-domain channel of the transmission channel, and calculate the initial delay coefficient according to the calculated correlation value; wherein, the calculation formula of the correlation value of the transmission channel is:

[0115]

[0116] The calculation formula of the initial delay coefficient is:

[0117]

[0118] Wherein, represents the correlation value of channel A1, represents the index set mapped by the local frequency-domain calibration sequence of channel A1 in the OFDM subcarriers, the elements of which form an arithmetic sequence with a common difference of K1 arranged from small to large, represents the set the j-th element of, is the frequency-domain channel estimated in step S31 related to channel A1, represents the subcarrier index the frequency-domain channel at, conj(x) represents taking the conjugate of the complex number x, N L is the number of subcarriers mapped by the local frequency-domain calibration sequence of the transmission channel in the OFDM subcarriers, that is, the number of elements of the set angle(x) represents taking the phase of x, N FFT represents the total number of subcarriers of the OFDM signal.

[0119] ​S313: Determine the maximum time delay value based on the calculated initial time delay coefficients of each transmission channel. Then set the maximum time delay to zero and calculate the time delay calibration coefficients of the transmission channels. Among them, the formula for the time delay calibration coefficient of channel A1 is:

[0120]

[0121] Where represents the time delay calibration coefficient of channel A1; t max represents the maximum time delay value; represents the initial time delay coefficient of channel A1.

[0122] Similarly, the above calculation method can be used to calculate the initial time delay coefficients of other channels and and the maximum time delay value t max ; set the maximum time delay to zero and calculate the time delay calibration coefficients of each channel, where i = 1, 2, …, M, j = M + 1, M + 2, …, N.

[0123] For the phase calibration coefficient, in this embodiment, taking the phase calibration coefficient of channel A1 as an example, its calculation method is as follows:

[0124] S411: Calculate the initial phase. Specifically, for channel A1, calculate the initial phase according to the frequency domain channel Calculate the initial phase

[0125] S412: Adjust the initial phase. Specifically, adjust the initial phase of transmission channel i to Where is the time delay calibration coefficient of channel A1;

[0126] S413: Process each element after the initial phase adjustment. Specifically, process for each element of, if then Where is the j-th element of;

[0127] S414: Take the mean of all elements of the adjusted phase to obtain the phase calibration coefficient of channel A1.

[0128] For other phase calibration coefficients and the calculation of is similar to the calculation of and will not be elaborated here.

[0129] For the amplitude calibration coefficient, its calculation method is as follows:

[0130] First, for the received sequence in the frequency domain of the transmitting channel and calculate the average power of the transmitting channel respectively to obtain and where the function mean(x) represents calculating the mean value of the vector x; each obtained channel power value is normalized with respect to and then take the square root to obtain the amplitude calibration coefficient of the transmitting channel

[0131] For the monitoring coefficient, the monitoring coefficient is the measured value of the channel signal-to-noise ratio. In this embodiment, taking the monitoring coefficient of channel A1 as an example, its calculation method is as follows:

[0132] First, calculate the average amplitude of the channel according to the estimated frequency-domain channel of the transmitting channel The calculation formula is:

[0133]

[0134] Then, construct the initial frequency-domain channel of the transmitting channel according to the average amplitude of the channel. The calculation formula is:

[0135]

[0136] where represents the initial frequency-domain channel of channel A1; represents the average amplitude of the channel of channel A1; represents the delay calibration coefficient of channel A1; represents the index set mapped by the local frequency-domain calibration sequence of channel A1 in the OFDM subcarriers;

[0137] Finally, calculate the monitoring coefficient of the transmitting channel according to the initial frequency-domain channel of the transmitting channel

[0138]

[0139] In the formula represents the monitoring coefficient of channel A1; represents the constructed initial frequency-domain channel of channel A1; represents the estimated frequency-domain channel of channel A1.

[0140] For other monitoring coefficients and their calculation is similar to that of and will not be elaborated here.

[0141] Thus, according to the above steps, the calibration coefficients of channels A1, A2, …, A connected between the first antenna array and the first signal processing unit are calculated, including: phase calibration coefficients M delay calibration coefficients amplitude calibration coefficients and monitoring coefficients And the calibration coefficients of the transmission channels B, B, …, B connected between the first antenna array and the second signal processing unit are calculated, including: phase calibration coefficients delay calibration coefficients M+1 , B M+2 , …, B N amplitude calibration coefficients and monitoring coefficients

[0142] Preferably, the first signal processing unit transmits the calibration coefficients of the transmission channels connecting the first antenna array and the second signal processing unit and the monitoring coefficients to the second signal processing unit through a data transmission line.

[0143] Finally, the first signal processing unit compensates the transmitted data according to the calibration coefficients of the transmission channels connecting the first antenna array and the first signal processing unit and monitors and feeds back the channel characteristics according to the monitoring coefficients.

[0144] The second signal processing unit compensates the transmitted data according to the calibration coefficients of the transmission channels connecting the first antenna array and the second signal processing unit and monitors and feeds back the channel characteristics according to the monitoring coefficients.

[0145] Specifically, for the delay calibration coefficient of channel A1 Compensation method: Let the transmitted data of channel A1 be x1, then x1 is transmitted after being delayed by a sampling clock.

[0146] For the phase calibration coefficient of channel A1 Compensation method: Let the transmitted data of channel A1 be x1, then the phase compensation result of x1 is

[0147] For the amplitude calibration coefficient of channel A1 Compensation method: Let the transmitted data of channel A1 be x1, then the amplitude compensation result of x1 is

[0148] Thus, the calibration and monitoring of the transmission channels connected between the first antenna array and the first signal processing unit and the second signal processing unit are realized.

[0149] Preferably, for task ②, its process schematic diagram is as Figure 6 shown, including the following steps:

[0150] S201: The first signal processing unit sends the local calibration sequence of the receiving channel through calibration channel A c The local calibration sequence passes through the coupler in the first antenna array, and the first signal processing unit obtains the calibration received sequences of channels A1, A2,..., A connected between the first antenna array and the first signal processing unit M The second signal processing unit obtains the calibration received sequences of channels B connected between the first antenna array and the second signal processing unit M+1 , B M+2 , …, B N

[0151] S202: The first signal processing unit calculates the calibration coefficients and monitoring coefficients of channels A1, A2,..., A connected between the first antenna array and the first signal processing unit according to the calibration received sequence of the receiving channel connected between the first antenna array and the first signal processing unit and the local calibration sequence of the receiving channel, including: phase calibration coefficient M delay calibration coefficient amplitude calibration coefficient and monitoring coefficient

[0152] The second signal processing unit calculates the calibration coefficients and monitoring coefficients of channels B connected between the first antenna array and the second signal processing unit according to the calibration received sequence of the receiving channel connected between the first antenna array and the second signal processing unit and the local calibration sequence of the receiving channel, including: phase calibration coefficient M+1 , B M+2 , …, B N delay calibration coefficient amplitude calibration coefficient and monitoring coefficient

[0153] S203: The first signal processing unit compensates the received data of the receiving channels connected between the first antenna array and the first signal processing unit according to the calibration coefficients of the receiving channels connected between the first antenna array and the first signal processing unit;

[0154] The second signal processing unit compensates the received data of the receiving channel connected between the first antenna array and the second signal processing unit according to the receiving channel calibration coefficient. Compensate the received data of the receiving channel connected between the first antenna array and the second signal processing unit.

[0155] Preferably, in the step S201, the generation method of the local calibration sequence of the receiving channel is as follows:

[0156] First, generate the receiving channel frequency domain sequence Use a pseudo-random sequence to generate the local frequency domain sequence of the receiving channel through BPSK (Binary Phase Shift Keying) modulation The local frequency domain sequence of the receiving channel is mapped to each sub-carrier of OFDM. Therefore its length is N FFT . The local frequency domain sequence of the receiving channel goes through an IFFT transformation of N FFT points to obtain the time domain sequence. After adding CP to each time domain sequence, the local calibration sequence of the receiving channel is obtained

[0157] Preferably, in the step S202,

[0158] For the delay calibration coefficient, in this embodiment, taking the delay calibration coefficient of channel A1 as an example, its calculation method includes the following steps:

[0159] S321: Remove the cyclic prefix CP from the calibration received sequence of the receiving channel and perform a fast Fourier transform FFT to obtain the frequency domain received sequence of the receiving channel and estimate the frequency domain channel of the receiving channel according to the frequency domain received sequence of the receiving channel and the local frequency domain sequence of the receiving channel

[0160] S322: Calculate the correlation value of the receiving channel according to the frequency domain channel, and calculate the initial delay coefficient of each receiving channel according to the calculated correlation value of the receiving channel. The initial delay coefficient of each channel is the delay calibration coefficient of the receiving channel; specifically:

[0161] Calculate the correlation value of the receiving channel according to the frequency domain channel of the receiving channel The calculation formula is:

[0162]

[0163] ​The calculation formula for the initial delay coefficient of the receiving channel is as follows:

[0164]

[0165] Wherein, represents the channel at the i-th subcarrier of the receiving channel, H L represents the number of elements of, and K2 is a set positive integer;

[0166] For the receiving channel, the receiving channel delay calibration coefficient

[0167] other delay calibration coefficients and The calculation of is similar to that of and will not be elaborated here.

[0168] For the phase calibration coefficient, in this embodiment, taking the phase calibration coefficient of channel A1 as an example, its calculation method includes the following steps:

[0169] S421: Calculate the initial phase. Specifically, for channel A1, according to the frequency-domain channel calculate the initial phase

[0170] S422: Adjust the initial phase. Specifically, adjust the initial phase of channel A1 to Wherein is the delay calibration coefficient of channel A1, and I is a positive integer taking values from 1 to H L ;

[0171] S423: Process each element after the initial phase adjustment. Specifically, for each element of, if then Wherein is the j-th element of;

[0172] S424: Take the mean value of all elements of the adjusted phase to obtain the phase calibration coefficient of channel A1.

[0173] Other phase calibration coefficients and The calculation of is similar to that of and will not be elaborated here.

[0174] For the amplitude calibration coefficient, its calculation method is as follows:

[0175] For the frequency-domain received sequence of the receiving channel and calculate the average power of the receiving channel respectively to obtain and According to the obtained power values of each channel, normalize and take the square root to obtain the amplitude calibration coefficient of the receiving channel

[0176] For the monitoring coefficient, in this embodiment, take the monitoring coefficient of channel A1 as an example, and its calculation method is as follows:

[0177] First, calculate the average amplitude of the receiving channel channel according to the estimated frequency-domain channel of the receiving channel Its calculation formula is:

[0178]

[0179]

[0179] Then, construct the initial frequency-domain channel of the receiving channel according to the average amplitude of the receiving channel channel Its calculation formula is:

[0180]

[0181] Finally, calculate the monitoring coefficient of the receiving channel according to the initial frequency-domain channel of the receiving channel

[0182]

[0183] The calculation of other monitoring coefficients and is similar to the calculation of and will not be elaborated here.

[0184] Thus, according to the above steps, calculate the calibration coefficients and monitoring coefficients of channels A1, A2,..., A M connected to the first signal processing unit of the first antenna array, including: phase calibration coefficient delay calibration coefficient amplitude calibration coefficient and monitoring coefficient

[0185] and calculate the calibration coefficients and monitoring coefficients of channels B M+1 , B M+2 ,..., B N connected to the second signal processing unit of the first antenna array, including: phase calibration coefficient delay calibration coefficient amplitude calibration coefficient and monitoring coefficients

[0186] Preferably, the last-mentioned first signal processing unit compensates the received data of the receiving channels connected between the first antenna array and the first signal processing unit according to the calibration coefficients of the receiving channels connected between the first antenna array and the first signal processing unit;

[0187] The second signal processing unit compensates the received data of the receiving channels connected between the first antenna array and the second signal processing unit according to the calibration coefficients of the receiving channels connected between the first antenna array and the second signal processing unit.

[0188] Specifically, the compensation method for the phase calibration coefficients of the receiving channels is as follows: Let the received data of channel A1 be x1, then the phase compensation result for x1 is

[0189] The compensation method for the delay calibration coefficients of the receiving channels is as follows: Let the received data of channel A1 be x1, then delay x1 by a sampling clock for reception.

[0190] The compensation method for the amplitude calibration coefficients of the receiving channels is as follows: Let the received data of channel A1 be x1, then the amplitude compensation result for x1 is

[0191] Preferably, for task ③, the calibration and monitoring of the transmitting channels connected between the second antenna array and the first signal processing unit and the second signal processing unit include the following steps:

[0192] S111: The antenna channels connected between the second antenna array and the first signal processing unit and the second signal processing unit respectively send the local calibration sequences of the transmitting channels, pass through the couplers and combiners in the second antenna array, and are transmitted to the calibration channels of the second signal processing unit to obtain the calibration received sequences of the transmitting channels;

[0193] S112: The second signal processing unit calculates the calibration coefficients and monitoring coefficients of the transmitting channels connected between the second antenna array and the first signal processing unit and the second signal processing unit according to the calibration received sequences of the transmitting channels and the local calibration sequences of the transmitting channels connected to the second antenna array;

[0194] S113: The second signal processing unit transmits the calibration coefficients and monitoring coefficients of the transmitting channels connected between the second antenna array and the first signal processing unit to the first signal processing unit through the data transmission line;

[0195] S114: The second signal processing unit compensates the transmitted data according to the transmission channel calibration coefficient of the second antenna array surface connected to the second signal processing unit; the first signal processing unit compensates the transmitted data according to the transmission channel calibration coefficient of the second antenna array surface connected to the first signal processing unit.

[0196] Preferably, for step S111, the generation method of the local calibration sequence is the same as that in step S101 of task ① for generating the local calibration sequence, which will not be elaborated here.

[0197] Preferably, for step S112, the calculation methods of the transmission channel calibration coefficient and the monitoring coefficient are the same as those in step S102 of task ① for the transmission channel calibration coefficient and the monitoring coefficient, which will not be elaborated here.

[0198] Preferably, for step S114, the method of compensating the transmitted data is the same as that in step S104 of task ① for compensating the transmitted data, which will not be elaborated here.

[0199] Preferably, for the reception channel calibration and monitoring of the second antenna array surface connected to the first signal processing unit and the second signal processing unit in task ④, it includes the following steps:

[0200] S211: The second signal processing unit sends the local calibration sequence of the reception channel through the calibration channel; the calibration sequence passes through the coupler in the second antenna array surface, and the second signal processing unit obtains the calibrated reception sequence of the reception channel of the second antenna array surface connected to the second signal processing unit; the first signal processing unit obtains the calibrated reception sequence of the reception channel of the second antenna array surface connected to the first signal processing unit;

[0201] S212: The second signal processing unit calculates the calibration coefficient and the monitoring coefficient of the reception channel of the second antenna array surface connected to the second signal processing unit according to the calibrated reception sequence of the reception channel of the second antenna array surface connected to the second signal processing unit and the local calibration sequence of the reception channel; the first signal processing unit calculates the calibration coefficient and the monitoring coefficient of the reception channel of the second antenna array surface connected to the first signal processing unit according to the calibrated reception sequence of the reception channel of the second antenna array surface connected to the first signal processing unit and the local calibration sequence of the reception channel;

[0202] S213: The second signal processing unit compensates the received data of the reception channel of the second antenna array surface connected to the second signal processing unit according to the calibration coefficient of the reception channel of the second antenna array surface connected to the second signal processing unit; the first signal processing unit compensates the received data of the reception channel of the second antenna array surface connected to the first signal processing unit according to the calibration coefficient of the reception channel of the second antenna array surface connected to the first signal processing unit.

[0203] Preferably, in the step S211, the method for generating the local calibration sequence is the same as that in the step S201 of Task ②, and will not be elaborated here.

[0204] Preferably, in the step S212, the calculation methods of the receiving channel calibration coefficient and the monitoring coefficient are the same as those in the step S202 of Task ②, and will not be elaborated here.

[0205] Preferably, in the step S213, the method for compensating the received data is the same as that in the step S203 of Task ②, and will not be elaborated here.

[0206] Further preferably, according to this embodiment, a multi-antenna channel calibration and monitoring method with a cross-connected dual-array structure is provided. When performing the multi-antenna channel calibration and monitoring of the cross-connected dual-array structure, the calibration and monitoring Task ① and ③ are executed simultaneously; the calibration and monitoring Task ② and ④ are executed simultaneously; or the calibration and monitoring Tasks ①②③④ are serially executed in any set order.

[0207] Further preferably, according to this embodiment, a multi-antenna channel calibration and monitoring method with a cross-connected dual-array structure is provided:

[0208] The calculation steps S101 to S103 of the calibration coefficient and the monitoring coefficient can be repeatedly executed multiple times to calculate the mean values of the corresponding calibration coefficients and monitoring coefficients, and are used for data compensation in step S104;

[0209] The calculation steps S201 to S202 of the calibration coefficient and the monitoring coefficient can be repeatedly executed multiple times to calculate the mean values of the corresponding calibration coefficients and monitoring coefficients, and are used for data compensation in step S203;

[0210] The calculation steps S111 to S113 of the calibration coefficient and the monitoring coefficient can be repeatedly executed multiple times to calculate the mean values of the corresponding calibration coefficients and monitoring coefficients, and are used for data compensation in step S114;

[0211] The calculation steps S211 to S212 of the calibration coefficient and the monitoring coefficient can be repeatedly executed multiple times to calculate the mean values of the corresponding calibration coefficients and monitoring coefficients, and are used for data compensation in step S213.

[0212] Further preferably, some minor modifications can be made to the method for generating the calibration signal. For example, in the solution of this embodiment, the calibration signal is generated by using a pseudo-random sequence + BPSK modulation, or it can also be generated by using a pseudo-random sequence + QPSK (Quadrature Phase Shift Keying) modulation, or other sequences are constructed + a certain QAM (Quadrature Amplitude Modulation) modulation is used for generation.

[0213] Further preferably, the calibration signal sent by the antenna to the transmission channel and the calibration channel may not be generated in real time when performing calibration and monitoring tasks. Instead, the calibration signal can be pre-generated and stored in the first signal processing unit and the second signal processing unit. When performing signal calibration, the signal can be directly called from the first signal processing unit and the second signal processing unit to calibrate the signal, thereby further improving the calibration efficiency of the antenna array.

[0214] Further preferably, not all of the calibration coefficients (amplitude calibration coefficient, phase calibration coefficient, delay calibration coefficient) need to be used for signal calibration. Specifically, in some actual application scenarios, for example, when the amplitude influence or change is small, only the phase calibration coefficient and the delay calibration coefficient can be selected to compensate for the phase and delay, so as to achieve signal calibration.

[0215] Obviously, the above embodiments of the present invention are merely examples for clearly explaining the technical solutions of the present invention, rather than limitations on the specific implementation manners of the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the claims of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A multi-antenna channel calibration and monitoring method with a cross-connected dual-array structure, characterized in that The method includes: calibrating and monitoring the transmission channels of several antenna arrays and several signal processing units with a cross-connected dual-array structure, and the steps are as follows: S11: Transmit the local calibration sequence of the transmission channel to the antenna channels respectively connected to different signal processing units of the antenna array, and transmit it to the calibration channel of one of the signal processing units to obtain the calibration received sequence of the transmission channel; S12: The one signal processing unit calculates the calibration coefficient and monitoring coefficient of the transmission channels connected to each signal processing unit of the antenna array according to the calibration received sequence of the transmission channel and the local calibration sequence of the transmission channel; S13: The one signal processing unit transmits the calibration coefficient and monitoring coefficient of the transmission channels connected to other signal processing units of the antenna array to other signal processing units through a data transmission line; S14: Each signal processing unit reports and indicates channel fault problems according to the monitoring coefficient, and compensates the transmitted data according to the calibration coefficient of the transmission channels connected to each signal processing unit of the antenna array; The method further includes: calibrating and monitoring the receiving channels of several antenna arrays and several signal processing units with a cross-connected dual-array structure, and the steps are as follows: S21: The signal processing unit transmits the local calibration sequence of the receiving channel through the calibration channel. After passing through the coupler in the antenna array, the signal processing unit obtains the calibration received sequence of the receiving channel connected to the antenna array and the signal processing unit; S22: The signal processing unit calculates the calibration coefficient and monitoring coefficient of the receiving channel connected to the antenna array and the signal processing unit according to the calibration received sequence of the receiving channel connected to the antenna array and the signal processing unit and the local calibration sequence of the receiving channel; S23: The signal processing unit reports and indicates channel fault problems according to the monitoring coefficient, and compensates the received data according to the calibration coefficient of the receiving channel connected to the corresponding signal processing unit of the antenna array.

2. The multi-antenna channel calibration and monitoring method with a cross-connected dual-array structure according to claim 1, wherein The local calibration sequence of the transmission channel is obtained by performing OFDM modulation on a pseudo-random sequence after constellation mapping in a frequency-division multiplexing manner to generate an OFDM symbol with a cyclic prefix; or by time-division multiplexing, or by performing OFDM modulation in a time / frequency-division multiplexing manner to generate multiple OFDM symbols with cyclic prefixes; The local calibration sequence of the receiving channel is obtained by performing OFDM modulation on a pseudo-random sequence after constellation mapping to generate an OFDM symbol with a cyclic prefix.

3. A multi-antenna channel calibration and monitoring method for a cross-connected dual-array structure according to claim 1, characterized in that, The calibration coefficient includes a delay calibration coefficient, and the delay calibration coefficient includes a transmission channel delay calibration coefficient and a receiving channel delay calibration coefficient; where The calculation method of the transmission channel delay calibration coefficient includes the following steps: S311: Remove the cyclic prefix from the calibration received sequence and perform a fast Fourier transform to obtain the frequency-domain received sequence, and estimate the frequency-domain channel according to the frequency-domain received sequence and the local frequency-domain sequence; S312: Calculate the transmission channel correlation value according to the frequency-domain channel, and calculate the initial delay coefficient of each transmission channel according to the calculated transmission channel correlation value; S313: Determine the maximum delay value according to the initial delay coefficients of each transmission channel, then reset the maximum delay to zero, and calculate the transmission channel delay calibration coefficient; The calculation method of the receiving channel delay calibration coefficient includes the following steps: S321: Remove the cyclic prefix from the calibrated received sequence and perform fast Fourier transform to obtain the frequency-domain received sequence, and estimate the frequency-domain channel based on the frequency-domain received sequence and the local frequency-domain sequence; S322: Calculate the receiving channel correlation value according to the frequency-domain channel, and calculate the initial delay coefficients of each receiving channel based on the calculated receiving channel correlation value. The initial delay coefficients of each channel are the receiving channel delay calibration coefficients.

4. A multi-antenna channel calibration and monitoring method for a cross-connected dual-array structure according to claim 3, characterized in that, In the step S312, the calculation formula of the transmission channel correlation value is: Among them, represents the relevant value of transmission channel i, i i represents the set of indices where the local frequency-domain calibration sequence of transmission channel i is mapped in the OFDM subcarriers, i i The elements of are arranged in ascending order to form an arithmetic sequence with a common difference of K1, i i (j) represents the set i i The j-th element of, is the frequency-domain channel related to transmission channel i, represents the subcarrier index i i The frequency-domain channel at (j), conj(x) represents the conjugate of the complex number x, N L is the number of subcarriers where the local frequency-domain calibration sequence of the transmission channel is mapped in the OFDM subcarriers, that is, the number of elements in the set i i ; The calculation formula of the initial delay coefficient of the transmission channel is: Among them, represents the initial delay coefficient of each transmission channel, angle(x) represents taking the phase of x, and N FFT represents the total number of subcarriers of the OFDM signal.

5. A multi-antenna channel calibration and monitoring method for a cross-connected dual-array structure according to claim 3, characterized in that In the step S322, the calculation formula of the receiving channel correlation value is: Among them, represents the relevant value of the receiving channel i, is the frequency-domain channel related to the receiving channel i, represents the frequency-domain channel at subcarrier index j, H L is the number of elements of, and K2 is a preset positive integer. The calculation formula of the initial delay coefficient of the receiving channel is: Among them, represents the initial delay coefficient of each receiving channel; angle(x) represents taking the phase of x, and N FFT represents the total number of subcarriers of the OFDM signal.

6. A multi-antenna channel calibration and monitoring method for a cross-connected dual-array structure according to any one of claims 4 or 5, characterized in that The calibration coefficient further includes a phase calibration coefficient, and the phase calibration coefficient includes a transmission channel phase calibration coefficient and a receiving channel phase calibration coefficient; where The calculation method of the transmission channel phase calibration coefficient includes the following steps: S411: Calculate the initial phase of the transmission channel, and calculate the initial phase of the transmission channel according to the frequency-domain channel related to transmission channel i to calculate the initial phase of the transmission channel S412: Adjust the initial phase of the transmission channel and adjust the initial phase of the transmission channel to where is the delay calibration coefficient of transmission channel i; S413: Process each element after the initial phase adjustment of the transmission channel. If then where is the j-th element of S414: Take the mean value of all elements of obtained in step S413 to obtain the phase calibration coefficient of the emission channel; The calculation method of the receiving channel phase calibration coefficient includes the following steps: S421: Calculate the initial phase of the receiving channel, based on the frequency-domain channel related to receiving channel i Calculate the initial phase of the receiving channel S422: Adjust the initial phase and adjust the initial phase of the receiving channel to where is the time delay calibration coefficient of the receiving channel, and I is a positive integer ranging from 1 to H L ; S423: Process each element after the initial phase adjustment of the receiving channel. If then where is the j-th element of S424: Take the mean of all elements of obtained in step S423 to get the receiving channel phase calibration coefficient.

7. A multi-antenna channel calibration and monitoring method for a cross-connected dual-array structure according to claim 3, characterized in that The calibration coefficient further includes an amplitude calibration coefficient, and the calculation method of the amplitude calibration coefficient is: calculate the average power of the frequency-domain received sequence, and perform normalization and square root processing on the average power of each channel with respect to the average power of the first channel, so as to obtain the amplitude calibration coefficient.

8. A multi-antenna channel calibration and monitoring method for a cross-connected dual-array structure according to claim 3, characterized in that The calculation method of the monitoring coefficient includes: calculate the channel average amplitude according to the estimated frequency-domain channel, then construct an initial frequency-domain channel based on the channel average amplitude, and then calculate the monitoring coefficient according to the initial frequency-domain channel.

9. A multi-antenna channel calibration and monitoring method with a cross-connected dual-array structure according to claim 8, characterized in that The calculation formula for calculating the monitoring coefficient according to the initial frequency-domain channel is: Among them, s i represents the monitoring coefficient of the i-th transmitting or receiving channel; represents the initial frequency-domain channel of the i-th transmitting or receiving channel constructed; H i represents the estimated frequency-domain channel of the i-th transmitting or receiving channel.

10. A multi-antenna channel calibration and monitoring method for a cross-connected dual-array structure according to any one of claims 1-9, characterized in that, Within a given time period, measure the channels by transmitting the local calibration sequence multiple times, and take the average values of the calibration coefficients and the monitoring coefficients obtained from multiple measurements respectively to obtain the final calibration coefficients and monitoring coefficients.

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