Space adaptive anti-jamming control method and device for TDMA broadband missile-borne frequency hopping data link

Abstract

The application relates to a TDMA wideband missile-borne frequency hopping data link space adaptive anti-interference control method and device, which comprises the following steps: converting N radio frequency wideband time-varying signals of a TDMA wideband frequency hopping data link into N intermediate frequency signals through down-conversion processing after the N radio frequency wideband time-varying signals are de-hopped; carrying out envelope detection processing on the N intermediate frequency signals to obtain N envelope voltage signals, and calibrating the N envelope voltage signals to eliminate the differences of receiving channels; judging whether there is interference in the receiving signal according to the N envelope voltage signals after calibration; when there is no interference signal in the receiving signal, calculating the antenna beam pointing according to the position and attitude information of a missile platform and antenna pointing wave control data, carrying out beam synthesis processing, synthesizing 1 receiving signal in the digital domain from the N intermediate frequency signals; otherwise, an adaptive nulling algorithm is adopted to generate adaptive nulling weights, the adaptive nulling weights are superimposed with non-interference beam control weights, beam synthesis processing is carried out, 1 receiving signal in the digital domain is synthesized from the N intermediate frequency signals, and space domain anti-interference receiving is realized.

Description

Technical Field

[0001] This invention relates to a TDMA wideband frequency hopping data link spatial adaptive anti-jamming control method and device, belonging to the field of military communication technology, and further to space-time joint anti-jamming communication technology. Background Technology

[0002] The communication access mechanism of the TDMA broadband frequency-hopping data link networking terminal is TDMA. To achieve anti-interference of the communication link, the signal adopts a frequency-hopping mechanism with a frequency-hopping bandwidth of 1 GHz. Frequency-hopping systems are divided into slow frequency-hopping systems and fast frequency-hopping systems. Frequency-hopping communication reduces the continuous overlap between communication signals and interference signals in the time and frequency domains by randomly hopping the radio frequency signal within a wide frequency band, thereby achieving the goal of minimizing or eliminating interference. Fast frequency-hopping systems have better anti-interception and anti-tracking interference performance and are generally used.

[0003] To improve the system's anti-interference capability, phased array antennas employ spatial adaptive nulling technology. Spatial adaptive nulling reduces the energy of interference signals from different directions entering the communication system by creating a gain null on the antenna beam in the direction of the interference signal's arrival, thereby improving the signal-to-interference ratio (SIR). Spatial adaptive nulling algorithms are divided into open-loop and closed-loop algorithms. For fast frequency hopping systems, it is necessary to quickly detect whether interference exists at each hop frequency. However, the convergence speed of the adaptive weighted vector in the closed-loop adaptive algorithm depends on the discreteness of the eigenvalues ​​of the input signal correlation matrix, resulting in unstable convergence speed and failing to meet the requirements of fast frequency hopping systems.

[0004] Commonly used adaptive zeroing optimal criteria include: Maximum Signal-to-Interference-Ratio (MSINR) criterion, Minimum Mean Square Error (MMSE) criterion, Linearly Constrained Minimum Variance (LCMV) criterion, and Maximum Likelihood (ML) criterion. The MSI criterion uses array assignment to generate null responses in the direction of interference arrival, ensuring minimal reception of the interference signal. The MMSE criterion uses a reference signal to cancel out unrelated interference signals. The ML criterion's core principle is to use known statistical characteristics of the interference signal to filter out interference components in the received signal, ensuring normal reception of the desired signal. The ML criterion's core principle is to use a reference channel signal to cancel out interference noise to ensure maximum suppression. Because it is difficult to obtain a set of reference signals highly correlated with the desired signal under practical conditions, and the characteristics of the interference signal cannot be predicted, the more universal MSI criterion is more commonly used in engineering applications.

[0005] The spatial adaptive zeroing algorithm faces two scenarios during operation: the presence of interference signals in the communication signal and the absence of interference signals. When there are no interference signals, the optimal approach is to skip spatial zeroing and directly transmit the interference-free signal to the backend signal processing circuit. Therefore, before using the spatial adaptive zeroing algorithm, interference detection should be performed on the communication frequency band to ensure the circuit operates in its optimal mode. Implementing interference detection and spatial adaptive zeroing algorithm control within the communication frequency band is a crucial step in achieving optimal adaptive anti-interference output for TDMA wideband frequency hopping data links.

[0006] However, with the depletion of low-frequency communication spectrum resources and the need for anti-interference, communication frequency bands are constantly being upgraded, gradually moving from L and S bands to Ku and Ka bands and even higher. According to spread spectrum communication theory, the spread / frequency hopping communication bandwidth selected by the communication system is much larger than the modulation bandwidth of the communication signal. Real-time interference spectrum detection in high-frequency bands and large bandwidths faces challenges such as high sampling frequency, wide sampling bandwidth, and large amount of sampled data processing, making technical implementation extremely difficult. Summary of the Invention

[0007] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide a TDMA wideband frequency hopping data link spatial adaptive anti-interference control method and device, which detects interference signals in the frequency hopping system and uses an adaptive zeroing algorithm in a timely manner to achieve spatial anti-interference.

[0008] The technical solution adopted in this invention is: a TDMA wideband missile-borne frequency hopping data link spatial domain adaptive anti-jamming control method, which includes the following steps:

[0009] The N radio frequency broadband time-varying signals of the TDMA broadband frequency hopping data link are de-hopped and then down-converted to N intermediate frequency signals, where N is the number of receiving channels of the TDMA broadband frequency hopping data link.

[0010] Envelope detection processing is performed on the N intermediate frequency signals to obtain N detector voltage signals, and the N detector voltage signals are calibrated to eliminate differences in the receiving channels;

[0011] Based on the calibrated N-channel detector voltage signals, determine whether there is interference in the received signal;

[0012] When there is no interference signal in the received signal, the antenna beam pointing is calculated based on the position and attitude information of the missile platform and the position information of the communication object. Then, the beam control data of each receiving channel is calculated. After the beam control data is used to perform amplitude and phase weighting processing on the N intermediate frequency signals, the N intermediate frequency signals are combined into 1 received signal in the digital domain.

[0013] When interference signals are present in the received signal, the zero-adjustment wave control value generated by the adaptive zero-adjustment algorithm is used to re-weight the received data of each channel that has already undergone antenna pointing weighting. Then, the N intermediate frequency signals are combined into one received signal in the digital domain to achieve spatial anti-interference reception.

[0014] Preferably, the method for calibrating the detection voltage is as follows: based on the detection voltage signal, retrieve the pre-stored detection voltage detection value-calibration factor lookup table for the corresponding channel to obtain the calibration factor, and subtract the calibration factor from the detection voltage signal to obtain the nominal detection voltage value;

[0015] Preferably, the calibration factor is determined by the following method:

[0016] In the laboratory, N receiving channels are calibrated in advance. By inputting signal levels of different strengths to the N receiving channels respectively, the measured values ​​of the detector voltage corresponding to different input signal strengths of each receiving channel are obtained. The difference between the measured value and the nominal value is used as the calibration factor.

[0017] Preferably, the method for determining whether interference exists in the received signal is as follows:

[0018] Determine if interference signals exist in each receiving channel:

[0019] When the detection voltage is higher than the "interference" threshold, it can be determined that there is an interference signal in the receiving channel.

[0020] When the detection voltage is lower than the "no interference" threshold, it can be determined that there is no interference signal in the receiving channel;

[0021] The system counts whether interference signals exist in N receiving channels. If interference signals are present in more than 2 / 3 of the receiving channels, the received signal is considered to have interference signals. If interference signals are not present in more than 2 / 3 of the receiving channels, the received signal is considered to have no interference signals. If the judgment result is between the presence of interference and the absence of interference, the previous judgment state is maintained.

[0022] Preferably, the "no interference" threshold is the upper limit of the detection voltage of the intermediate frequency signal, and the "interference" threshold is twice the "no interference" threshold.

[0023] Preferably, when the detection voltage is between the "no interference" threshold and the "interference" threshold, the presence or absence of interference signals in the receiving channel remains unchanged.

[0024] Another technical solution of the present invention is: a TDMA broadband frequency hopping data link spatial adaptive anti-interference control device, which includes a phased array antenna module, a transceiver array module, an antenna nulling processing module, a data processing module, and a network control module;

[0025] The phased array antenna module uses N unit antennas to simultaneously receive TDMA broadband frequency hopping data link signals. After down-conversion, filtering, and amplification, N channels of RF broadband time-varying signals are obtained and sent to the transceiver array module. It receives one channel of transmit RF signal from the transceiver array module, divides it into N channels, performs phase shifting and amplification on each channel, and then sends them to N antenna elements to radiate into space.

[0026] The transceiver array module de-bounces N channels of broadband time-varying RF signals, performs down-conversion processing to convert them into N channels of intermediate frequency (IF) signals, and sends the IF signals to the antenna nulling module. It performs envelope detection processing on each IF signal to obtain a detection voltage signal, which is then sent to the data processing circuit. The module amplifies and up-converts the 1-channel transmit signal from the data processing module and sends it to the phased array antenna module.

[0027] The data processing module calibrates the N envelope detection voltage signals sent by the transceiver array module. Based on the calibrated N detection voltage signals, it determines whether there is interference in the received signal and outputs the result to the antenna nulling processing module. The module then acquires, tracks, despreads, and demodulates one synthesized signal output from the antenna nulling processing module to obtain the received data, which is then sent to the network control module. Finally, the module frames, encodes, modulates, and converts the data to be transmitted by the missile platform to obtain the transmit signal, which is then sent to the transceiver array module.

[0028] When there is no interference in the received signal, the antenna nulling processing module calculates the antenna beam pointing based on the missile platform's position and attitude information, as well as the position information of the communication target. It then calculates the beam control data for each receiving channel. After amplitude and phase weighting of the intermediate frequency (IF) signal using the beam control data, the N IF signals are synthesized into one received signal in the digital domain. When interference exists in the received signal, the nulling beam control weights generated by the adaptive nulling algorithm are used to re-weight the received data from each channel that has already undergone antenna pointing weighting. The N IF signals are then synthesized into one received signal in the digital domain, achieving anti-interference reception in the spatial domain. The single received signal output by the antenna nulling processing module is sent to the data processing module for demodulation, decoding, and other processing.

[0029] The network control module sends the missile platform's position and attitude information to the antenna nulling processing module; sends the data that the missile platform needs to transmit to the data processing module; outputs the received data processed by the data processing module to the missile platform; and is responsible for generating transmit and receive time slot flags and sending the transmit and receive time slot flags to the data processing module and the phased array antenna module in real time, thereby controlling the transmit and receive status of the data processing module and the phased array antenna module.

[0030] Preferably, the method for calibrating the detection voltage is as follows: based on the detection voltage signal, retrieve the pre-stored detection voltage detection value-calibration factor lookup table for the corresponding channel to obtain the calibration factor, and subtract the calibration factor from the detection voltage signal to obtain the nominal detection voltage value;

[0031] Preferably, the calibration factor is determined by the following method:

[0032] In the laboratory, N receiving channels are calibrated in advance. By inputting signal levels of different strengths to the N receiving channels respectively, the measured values ​​of the detector voltage corresponding to different input signal strengths of each receiving channel are obtained. The difference between the measured value and the nominal value is used as the calibration factor.

[0033] Preferably, the method for determining whether interference exists in the received signal is as follows:

[0034] Determine if there are interference signals in each receiving channel;

[0035] When the detection voltage is higher than the "interference" threshold, it can be determined that there is an interference signal in the receiving channel.

[0036] When the detection voltage is lower than the "no interference" threshold, it can be determined that there is no interference signal in the receiving channel;

[0037] The system counts whether interference signals exist in N receiving channels. If interference signals are present in more than 2 / 3 of the receiving channels, the received signal is considered to have interference signals. If interference signals are not present in more than 2 / 3 of the receiving channels, the received signal is considered to have no interference signals. If the judgment result is between the presence of interference and the absence of interference, the previous judgment state is maintained.

[0038] The beneficial effects of this invention compared to the prior art are as follows:

[0039] (1) This invention maps high-frequency broadband frequency-hopping signals to intermediate frequency narrowband signals, making interference detection within a large bandwidth of high frequency possible. Moreover, it avoids the complicated process of high-frequency radio frequency sampling and analysis when the intermediate frequency channel is detected and mapped to the radio frequency channel and is subject to interference.

[0040] (2) In this invention, the detection signal is conditioned, and the interference decision threshold can be adjusted according to the different receiving sensitivities of receivers in different systems, which has strong system applicability.

[0041] (3) The present invention uses the medium frequency detection method, which has the characteristics of low cost. Attached Figure Description

[0042] Figure 1 This is a block diagram of the network terminal composition of a TDMA broadband frequency hopping data link spatial adaptive anti-interference control method according to the present invention;

[0043] Figure 2 This is a functional block diagram of a network terminal for a TDMA broadband frequency hopping data link spatial adaptive anti-interference control method according to the present invention.

[0044] Figure 3 This is the workflow of a TDMA wideband frequency hopping data link spatial domain adaptive anti-interference control method according to the present invention. Detailed Implementation

[0045] The implementation and effects of the present invention will be described in further detail below.

[0046] The spatial adaptive nulling algorithm faces two scenarios during operation: the presence of interference signals in the communication signal and the absence of interference signals. When there are no interference signals, the optimal approach is to skip spatial nulling and directly transmit the interference-free signal to the backend signal processing circuitry. Therefore, before using the spatial adaptive nulling algorithm, interference detection should be performed on the communication frequency band to ensure the spatial adaptive nulling circuit operates in its optimal mode. Implementing interference detection and spatial adaptive nulling algorithm control within the communication frequency band is a crucial step in the adaptive anti-interference mechanism of TDMA wideband frequency-hopping data links.

[0047] Based on the above design concept, this invention provides a TDMA wideband airborne frequency hopping data link spatial domain adaptive anti-jamming control method, which includes the following steps:

[0048] The N radio frequency broadband time-varying signals of the TDMA broadband frequency hopping data link are de-hopped and then down-converted to N intermediate frequency signals, where N is the number of receiving channels of the TDMA broadband frequency hopping data link.

[0049] Envelope detection processing is performed on the N intermediate frequency signals to obtain N detector voltage signals, and the N detector voltage signals are calibrated to eliminate differences in the receiving channels;

[0050] Based on the calibrated N-channel detector voltage signals, determine whether there is interference in the received signal;

[0051] When there is no interference signal in the received signal, the antenna beam pointing is calculated based on the position and attitude information of the missile platform and the position information of the communication object. Then, the beam control data of each receiving channel is calculated. After the intermediate frequency signal is processed by amplitude and phase weighting using the beam control data, the N intermediate frequency signals are combined into 1 receiving signal in the digital domain.

[0052] When interference signals are present in the received signal, the zero-adjustment wave control value generated by the adaptive zero-adjustment algorithm is used to re-weight the received data of each channel that has already undergone antenna pointing weighting. Then, the N intermediate frequency signals are combined into one received signal in the digital domain to achieve spatial anti-interference reception.

[0053] For the same received signal input level, after N-channel receiving frequency conversion and amplification, the detection voltage of the N intermediate frequency signals should be consistent. The reasons for inconsistency include inconsistent gains of the N-channel receiving frequency conversion channels and inconsistent linearity of the N-channel detection circuits.

[0054] The nominal output voltage of the detector is expressed in V. DO :

[0055] V DO =β v ×(P in +G n (1)

[0056] Where: β v --Nominal voltage sensitivity of the detector

[0057] P in --Receiver channel input signal level

[0058] G n --Nominal gain of the receiving channel

[0059] The actual output voltage of the detector is expressed as V. DT :

[0060] V DT =β vT ×(P in +G T (2)

[0061] Where: β vT -- Actual voltage sensitivity of the detector

[0062] G T --Measured gain of the receiving channel

[0063] Detector voltage calibration value ΔV a for:

[0064] ΔV a =V DT -V DO (3)

[0065] The method for calibrating the detection voltage is as follows: based on the detection voltage signal, retrieve the pre-stored detection voltage detection value-calibration factor lookup table for the corresponding channel to obtain the calibration factor, and subtract the calibration factor from the detection voltage signal to obtain the nominal detection voltage value.

[0066] The calibration factor was determined by the following method:

[0067] In the laboratory, N receiving channels are calibrated in advance. By inputting signal levels of different strengths to the N receiving channels respectively, the measured values ​​of the detector voltage corresponding to different input signal strengths of each receiving channel are obtained. The difference between the measured value and the nominal value is used as the calibration factor.

[0068] As a preferred option, the nominal value corresponding to the measured value can also be saved directly. When indexing, the nominal voltage value of the detector can be obtained directly from the measured value.

[0069] The method for determining whether there is interference in the received signal is as follows:

[0070] Determine if interference signals exist in each receiving channel:

[0071] When the detection voltage is higher than the "interference" threshold, it can be determined that there is an interference signal in the receiving channel.

[0072] When the detection voltage is lower than the "no interference" threshold, it can be determined that there is no interference signal in the receiving channel;

[0073] The system counts whether interference signals exist in N receiving channels. If interference signals are present in more than 2 / 3 of the receiving channels, the system considers that interference signals exist in the received signals; otherwise, the system considers that interference signals do not exist in the received signals.

[0074] The "no interference" threshold is the upper limit of the detection voltage of the intermediate frequency signal, and the "interference" threshold is twice the "no interference" threshold.

[0075] When the detection voltage is between the "no interference" threshold and the "interference" threshold, the presence or absence of interference signals in the receiving channel remains unchanged.

[0076] The TDMA broadband frequency hopping data link spatial adaptive anti-interference control device includes a phased array antenna module, a transceiver array module, an antenna nulling processing module, a data processing module, and a network control module.

[0077] The phased array antenna module uses N element antennas to simultaneously receive TDMA broadband frequency hopping data link signals. After down-conversion, filtering, and amplification, N broadband time-varying RF signals are obtained and sent to the transceiver array module. It receives RF signals from the transceiver array module, amplifies the signals, and radiates them into space. It receives beam control and power control commands from the network control module to achieve antenna beam pointing control and power control. It feeds back status information such as beam pointing angle, power, and beam status to the network control module.

[0078] The transceiver array module includes a high-stability frequency source, frequency synthesis circuit, frequency multiplier chain, up-conversion, down-conversion, and envelope detection functions. It de-bounces N channels of broadband time-varying RF signals, performs down-conversion processing to convert them into N channels of intermediate frequency (IF) signals, and sends these IF signals to the antenna nulling module. Each IF signal undergoes envelope detection processing to obtain a detection voltage signal, which is then sent to the data processing circuit. Finally, it amplifies and up-converts one transmit signal from the data processing module before sending it to the phased array antenna module.

[0079] The data processing module calibrates the N envelope detection voltage signals sent by the transceiver array module. Based on the calibrated N detection voltage signals, it determines whether there is interference in the received signal and outputs the result to the antenna nulling processing module. The module then acquires, tracks, despreads, and demodulates one synthesized signal output from the antenna nulling processing module to obtain the received data, which is then sent to the network control module. Finally, the module frames, encodes, modulates, and converts the data to be transmitted by the missile platform to obtain the transmit signal, which is then sent to the transceiver array module.

[0080] The antenna nulling processing module, when there is no interference in the received signal, calculates the antenna signal AD data based on the missile platform's position and attitude information, as well as the communication target's position information. After amplitude and phase weighting processing, it synthesizes the N intermediate frequency signals into one received signal in the digital domain. When interference exists in the received signal, the nulling wave control value generated by the adaptive nulling algorithm is used to re-weight the received data of each channel that has already undergone antenna pointing weighting processing. Then, the N intermediate frequency signals are synthesized into one received signal in the digital domain, achieving airspace anti-interference reception. The single received signal output by the antenna nulling processing module is sent to the data processing module for demodulation, decoding, and other processing.

[0081] The network control module sends the missile platform's position and attitude information to the phased array antenna module; sends the data that the missile platform needs to transmit to the data processing module; outputs the received data processed by the data processing module; and is responsible for generating transmit and receive time slot flags and sending the transmit and receive time slot flags to the data processing module and the phased array antenna module in real time, thereby controlling the transmit and receive status of the data processing module and the phased array antenna module.

[0082] Example:

[0083] In a specific embodiment of this invention, the communication networking subsystem of the intelligent collaborative strike system mainly completes the networking, information distribution, and information sharing of flight platforms. The system consists of a network formed by the collaborative operation of networking terminals from multiple flight platforms. Each terminal comprises one networking terminal and three phased array antennas. The networking terminal's transceiver array module amplifies and down-converts the received signal from the antennas while simultaneously de-hopping the frequency-hopping signal, converting the system's broadband signal into a narrowband signal. For each RF hop, the down-converted / de-hopped signal becomes a fixed intermediate frequency (IF). Detection of the IF signal allows for the determination of its power. In the presence of interference, the detection output voltage is significantly higher than in the absence of interference. Conditioning the detected signal reveals that the output voltage is less than 1V in the absence of interference, and greater than 2V indicates interference in the received signal. The transceiver array module detects all 16 demodulated IF signals and sends the detection results to the zero-adjustment processing module, which then determines whether to operate in anti-interference mode.

[0084] This embodiment is based on a TDMA wideband frequency-hopping data link system. The target application of this system is the communication networking subsystem of an intelligent collaborative strike system, which mainly completes networking, information distribution, and information sharing among flight platforms. The system consists of a network formed by the collaborative operation of networking terminals from multiple flight platforms. Each terminal consists of one networking terminal and three phased array antennas, such as... Figure 1 As shown.

[0085] The main functions of the networking terminal include:

[0086] 1) Receive information from the flight control computer, and perform encoding, modulation, up-conversion, and radio frequency output to the phased array antenna for radiation into space;

[0087] 2) The phased array antenna receives the radio frequency signals in space and sends them to the network terminal, which performs down-conversion, demodulation, decoding and other signal processing, and sends the restored information to the flight control computer.

[0088] 3) Based on the platform position and attitude data sent by the flight control computer, select the phased array antenna and calculate the antenna beam pointing angle to control the antenna beam to point towards the communication target;

[0089] 4) Enables switching between transmit and receive modes, wide beam and narrow beam modes, full power transmit and low power transmit modes, and switching between different communication rates in narrow beam mode;

[0090] 5) The multiple received signals output by the phased array antenna are suppressed by the spatial anti-interference adaptive nulling algorithm in the network terminal.

[0091] 6) Implement communication protocol control when multiple nodes are networked.

[0092] The functional block diagram of the networking terminal is as follows: Figure 2 As shown.

[0093] The adaptive nulling algorithm needs to distinguish between an interference-prone and interference-free signal. When interference is present, the nulling processing module operates in anti-interference mode, generating adaptive nulling weights. When there is no interference in the received signal, the nulling processing module operates in non-anti-interference mode, generating corresponding DBF weights to maintain the antenna's main beam unchanged.

[0094] Whether the frequency-hopping signal is subject to interference needs to be detected before the signal is sent to the zeroing processing module. Figure 2 It is known that the transceiver array module needs to determine whether the received signal is superimposed with interference.

[0095] After channel de-hopping, the network terminal outputs an intermediate frequency (IF) signal, transforming broadband interference detection within the frequency hopping bandwidth into narrowband interference detection within the signal bandwidth. An energy detection method is used to detect the energy in the received channel. The detection result is compared with preset judgment conditions to determine whether interference exists in the channel. The adaptive interference detection control process of this invention is as follows: Figure 3 As shown, the specific steps are as follows:

[0096] Step S1: Convert the system's RF broadband time-varying signal into a fixed intermediate frequency narrowband signal: The network terminal transceiver array module amplifies the 16 received signals with a bandwidth of 1GHz sent by the antenna, downconverts the frequency, and de-hops the frequency hopping signal to output an intermediate frequency signal with a bandwidth of 20MHz.

[0097] Step S2: Detect the 16 intermediate frequency signals respectively: output the 16 detection voltages as the source data for interference decision, and the detection voltage range is 0V~5V.

[0098] Step S3: Conditioning the Detected Signals: Due to the inconsistency in the gain of the 16 receiving channels and the inconsistency in the linearity of the detection circuit, the accuracy of the 16 detected signals has a certain deviation. During the product manufacturing process, the gain of the 16 receiving channels and the linearity of the detection circuit are measured, and the measurement results are stored as detection voltage calibration data in the data processing module. In actual use, the data processing module samples, quantizes, and calibrates the 16 detected signals to eliminate the data dispersion caused by the differences in the receiving channels, obtaining a relatively accurate detected value of the signal strength in the channel.

[0099] Step S4: Output Channel Detection Results: Set the detection voltage of the maximum value of the received intermediate frequency (IF) signal during normal communication between network nodes to 1V. The detection voltage range for the received IF signal during communication between network nodes is 0V to 1V. When the detection voltage is higher than 1V, it can be determined that there is interference in the receiving channel. When the interference signal reaches a certain strength, the zero-adjustment processing module needs to be activated. Transmission errors caused by weak interference signals can be corrected using channel coding. Perform amplitude statistics on the 16 conditioned detection voltages. When 12 detection voltages are less than 1V, it is determined that there is no interference in the receiving channel, and a value of "0" is assigned to the zero-adjustment processing module. When 12 detection voltages are greater than 2V, it is determined that there is interference in the receiving channel, and a value of "1" is assigned to the zero-adjustment processing module. To avoid the ping-pong effect, when the detection voltage is between 1V and 2V, the value assigned to the zero-adjustment processing module remains unchanged from the previous assignment.

[0100] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. A TDMA wideband airborne frequency hopping data link spatial domain adaptive anti-jamming control method, characterized in that... Includes the following steps: The N radio frequency broadband time-varying signals of the TDMA broadband frequency hopping data link are de-hopped and then down-converted to N intermediate frequency signals, where N is the number of receiving channels of the TDMA broadband frequency hopping data link. Envelope detection processing is performed on the N intermediate frequency signals to obtain N detector voltage signals, and the N detector voltage signals are calibrated to eliminate differences in the receiving channels; Based on the calibrated N-channel detector voltage signals, determine whether there is interference in the received signal; When there is no interference signal in the received signal, the antenna beam pointing is calculated based on the position and attitude information of the missile platform and the position information of the communication object. Then, the beam control data of each receiving channel is calculated. After the beam control data is used to perform amplitude and phase weighting processing on the N intermediate frequency signals, the N intermediate frequency signals are combined into 1 received signal in the digital domain. When interference signals are present in the received signal, the nulling wave control value generated by the adaptive nulling algorithm is used to re-weight the received data of each channel that has already undergone antenna pointing weighting. Then, the N intermediate frequency signals are combined into one received signal in the digital domain to achieve spatial anti-interference reception. The method for calibrating the detection voltage is as follows: based on the detection voltage signal, retrieve the pre-stored detection voltage detection value-calibration factor lookup table for the corresponding channel to obtain the calibration factor, and subtract the calibration factor from the detection voltage signal to obtain the nominal detection voltage value; The calibration factor was determined by the following method: In the laboratory, N receiving channels are calibrated in advance. By inputting signal levels of different strengths to the N receiving channels respectively, the measured values ​​of the detector voltage corresponding to different input signal strengths of each receiving channel are obtained. The difference between the measured value and the nominal value is used as the calibration factor. The method for determining whether there is interference in the received signal is as follows: Determine if interference signals exist in each receiving channel: When the detection voltage is higher than the "interference" threshold, it can be determined that there is an interference signal in the receiving channel. When the detection voltage is lower than the "no interference" threshold, it can be determined that there is no interference signal in the receiving channel; The system counts whether interference signals exist in N receiving channels. If interference signals are present in more than 2 / 3 of the receiving channels, the received signal is considered to have interference signals. If interference signals are not present in more than 2 / 3 of the receiving channels, the received signal is considered to have no interference signals. If the judgment result is between the presence of interference and the absence of interference, the previous judgment state is maintained.

2. The TDMA wideband airborne frequency hopping data link spatial domain adaptive anti-jamming control method according to claim 1, characterized in that... The "no interference" threshold is the upper limit of the detection voltage of the intermediate frequency signal, and the "interference" threshold is twice the "no interference" threshold.

3. The TDMA wideband airborne frequency hopping data link spatial domain adaptive anti-jamming control method according to claim 1, characterized in that... When the detection voltage is between the "no interference" threshold and the "interference" threshold, the presence or absence of interference signals in the receiving channel remains unchanged.

4. A TDMA broadband frequency hopping data link spatial adaptive anti-interference control device, characterized in that... It includes a phased array antenna module, a transceiver array module, an antenna nulling processing module, a data processing module, and a network control module; The phased array antenna module uses N unit antennas to simultaneously receive TDMA broadband frequency hopping data link signals. After down-conversion, filtering, and amplification, N radio frequency broadband time-varying signals are obtained and sent to the transceiver array module. It receives one transmit RF signal from the transceiver array module, divides the power into N channels, performs phase-shift amplification on each channel, and then sends them to N antenna elements to radiate into space. The transceiver array module de-bounces N channels of broadband time-varying RF signals, performs down-conversion processing to convert them into N channels of intermediate frequency (IF) signals, sends the IF signals to the antenna nulling module, performs envelope detection processing on each IF signal, and sends the obtained detection voltage signal to the data processing circuit. The one-channel transmit signal from the data processing module is amplified, up-converted, and then sent to the phased array antenna module. The data processing module calibrates the N envelope detection voltage signals sent by the transceiver array module, determines whether there is interference in the received signal based on the calibrated N detection voltage signals, and outputs the judgment result to the antenna nulling processing module. The synthesized signal output from the antenna nulling processing module is acquired, tracked, despread, and demodulated to obtain received data, which is then sent to the network control module. The data that the missile platform needs to transmit is framed, encoded, modulated, and converted from digital to analog to obtain the transmit signal, which is then sent to the transceiver array module. When there is no interference in the received signal, the antenna nulling processing module calculates the antenna beam pointing based on the missile platform's position and attitude information, as well as the position information of the communication target. It then calculates the beam control data for each receiving channel. After amplitude and phase weighting of the intermediate frequency (IF) signal using the beam control data, the N IF signals are synthesized into one received signal in the digital domain. When interference exists in the received signal, the adaptive nulling algorithm generates nulling beam control weights, which are then used to re-weight the received data from each channel that has already undergone antenna pointing weighting. The N IF signals are then synthesized into one received signal in the digital domain, achieving anti-interference reception in the spatial domain. The single received signal output by the antenna nulling processing module is sent to the data processing module for demodulation and decoding. The network control module sends the missile platform's position and attitude information to the antenna nulling processing module; sends the data that the missile platform needs to transmit to the data processing module; outputs the received data processed by the data processing module to the missile platform; and is responsible for generating transmit and receive time slot flags and sending the transmit and receive time slot flags to the data processing module and the phased array antenna module in real time, thereby controlling the transmit and receive status of the data processing module and the phased array antenna module. The method for calibrating the detection voltage is as follows: based on the detection voltage signal, retrieve the pre-stored detection voltage detection value-calibration factor lookup table for the corresponding channel to obtain the calibration factor, and subtract the calibration factor from the detection voltage signal to obtain the nominal detection voltage value. The calibration factor was determined by the following method: In the laboratory, N receiving channels are calibrated in advance. By inputting signal levels of different strengths to the N receiving channels respectively, the measured values ​​of the detector voltage corresponding to different input signal strengths of each receiving channel are obtained. The difference between the measured value and the nominal value is used as the calibration factor. The method for determining whether there is interference in the received signal is as follows: Determine if there are interference signals in each receiving channel; When the detection voltage is higher than the "interference" threshold, it can be determined that there is an interference signal in the receiving channel. When the detection voltage is lower than the "no interference" threshold, it can be determined that there is no interference signal in the receiving channel; The system counts whether interference signals exist in N receiving channels. If interference signals are present in more than 2 / 3 of the receiving channels, the received signal is considered to have interference signals. If interference signals are not present in more than 2 / 3 of the receiving channels, the received signal is considered to have no interference signals. If the judgment result is between the presence of interference and the absence of interference, the previous judgment state is maintained.

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