Ultra-short wave frequency hopping radio interference cancellation device and method

Abstract

The application provides an ultrashort wave frequency hopping radio interference cancellation device and method, and belongs to the technical field of communication anti-interference, wherein the radio frequency switch module is used for transmitting the radio frequency signal of the receiving antenna to the frequency hopping radio through switching based on the first control instruction, or transmitting the initial radio frequency signal to the frequency hopping receiving module, and transmitting the cancellation playback radio frequency signal to the frequency hopping radio; the frequency hopping receiving module is used for performing out-of-band filtering and down-conversion processing on the initial radio frequency signal to obtain a baseband IQ signal; the interference cancellation module is used for suppressing the interference signal of the baseband IQ signal and outputting a residual signal after cancellation processing; and the frequency hopping transmitting module is used for outputting the cancellation playback radio frequency signal to the radio frequency switch module after up-conversion of the residual signal. The application has the characteristics of fast cancellation speed, small delay and strong anti-interference ability.

Description

Technical Field

[0001] The present application belongs to the field of communication anti-interference technology, and more specifically, relates to an ultra-short wave frequency hopping radio interference cancellation device and method. Background Art

[0002] Communication radios often face harsh electromagnetic environments. Under strong interference conditions, the development of frequency hopping technology has enabled radios to avoid targeted jamming on certain frequencies, providing a certain degree of anti-interference capability. However, advances in electronic countermeasures have made full-band, high-intensity blocking jamming a reality. When attackers apply high-intensity, full-band suppression jamming, frequency hopping communications run out of available frequencies, resulting in communication interruption. RF tuning reception and weighted combining interference cancellation are key technologies for addressing this interference problem.

[0003] The basic concept of RF tuned reception technology is to utilize RF tuned filtering based on the operating mechanism of ultra-shortwave frequency-hopping radios. The challenge lies in achieving fast link establishment and high out-of-band rejection in high-hopping modes, while also ensuring hardware design that balances high sensitivity and wide dynamics. Current RF systems have long frequency setup and switching times, failing to meet the requirements for RF link cancellation at thousands of hops. Out-of-band rejection is typically 30-40dB @ frequency offset x 5%. High-power out-of-band interference compresses the RF system's dynamic range, impacting signal reception. Furthermore, high-sensitivity and wide-dynamic RF link design are prerequisites for high-performance interference cancellation.

[0004] The principle of weighted combining interference cancellation technology is to adjust the gain of multi-antenna receiving signals and synthesize them to eliminate the interference signal at the receiving end. According to different implementation methods, current interference cancellation technologies are mainly divided into analog interference cancellation technology and digital interference cancellation technology. Analog interference cancellation technology refers to the use of analog signal processing to complete signal reconstruction in the RF domain. Its advantage is a larger dynamic range, but it has limitations such as difficulty in hardware implementation, high insertion loss, weak adaptive adjustment capability, and slow cancellation speed. Digital domain interference cancellation technology refers to the use of digital signal processing to reconstruct interference signals in the digital domain, avoiding the problems of difficult multi-tap implementation, high insertion loss, difficult adaptive adjustment of combining weights, and slow cancellation speed. However, the existing digital domain interference cancellation technology needs to complete the processing of the received signal and then feed it back to the receiving end, which can easily cause delay in the received signal. Summary of the Invention

[0005] In view of the defects of the prior art, the purpose of this application is to provide an ultra-short wave frequency hopping radio interference cancellation device and method, aiming to solve the problems of poor blocking capability, long convergence time and large delay in interference suppression in the existing anti-blocking reception and digital interference cancellation methods.

[0006] To achieve the above objectives, on the one hand, the present application provides a device for canceling interference of an ultra-short wave frequency hopping radio station, comprising:

[0007] The sampling antenna module is used to output a multi-channel RF signal, which together with the RF signal output by the receiving antenna constitutes an initial RF signal;

[0008] A radio frequency switch module, whose input end is provided with a receiving antenna and a sampling antenna, whose input end is connected to the frequency hopping transmitting module, and whose output end is connected to the radio frequency receiving module and the frequency hopping radio, is used to transmit the radio frequency signal of the receiving antenna to the frequency hopping radio through switch switching based on the first control instruction; or transmit the initial radio frequency signal to the frequency hopping receiving module, and transmit the playback radio frequency signal to the frequency hopping radio;

[0009] A frequency hopping receiving module, whose output end is connected to the interference cancellation module, the interference sensing module and the frequency hopping transmitting module, is used to perform out-of-band filtering and down-conversion processing on the initial RF signal based on the second control instruction to obtain a baseband IQ signal (baseband in-phase and quadrature signal);

[0010] An interference cancellation module, whose output end is connected to the frequency hopping transmission module, is used to suppress the interference signal of the baseband IQ signal based on the third control instruction and output the residual signal after the cancellation processing;

[0011] An interference perception module is configured to output an interference perception indication signal based on a baseband IQ signal;

[0012] A display control module, whose input end is connected to the interference perception module, and whose output end is connected to the RF switch module, the frequency hopping receiving module, the interference cancellation module and the frequency hopping transmitting module, is used to output a first control instruction, a second control instruction, a third control instruction and a fourth control instruction based on the interference perception indication signal and the frequency word information of the frequency hopping radio station, which are used to control the RF switch state, the frequency hopping receiving local oscillator, the interference cancellation algorithm parameters and the frequency hopping transmitting local oscillator respectively;

[0013] The frequency hopping transmission module has an output end connected to the RF switch module and is used to up-convert the residual signal based on the fourth control instruction and then output the cancellation playback RF signal to transmit to the RF switch module.

[0014] It should be pointed out here that the RF switch module switches between the pass-through and access states by switching the switch; the pass-through state is when the interference signal in the RF signal transmitted by the receiving antenna is less than the preset interference threshold, the frequency hopping radio is in the transmitting state, and the frequency hopping radio is directly connected to the receiving antenna by switching the switch, and the RF signal transmitted by the receiving antenna is directly transmitted to the frequency hopping radio; the access state is when the interference signal in the RF signal transmitted by the receiving antenna is greater than or equal to the preset interference threshold, the frequency hopping radio is in the receiving state, and the initial RF signal is cancelled by switching the switch, and the initial RF signal is transmitted to the frequency hopping receiving module, down-converted to a baseband IQ signal, and after cancellation processing, returned to the RF switch module through the frequency hopping transmitting module;

[0015] Further preferably, the radio frequency switch module includes a first mechanical switch, a second mechanical switch, a first three-phase electronic switch, a second three-phase electronic switch and N-1 two-phase electronic switches;

[0016] The input end of the first mechanical switch is connected to the output end of the second mechanical switch and the output end of the first three-phase electronic switch, and is used to output the radio frequency signal of the receiving antenna transmitted by the second mechanical switch to the frequency hopping radio station, or to transmit the cancellation and playback radio frequency signal output by the first three-phase electronic switch to the frequency hopping radio station;

[0017] The other output end of the second mechanical switch is connected to the input end of the second three-phase electronic switch. One output end of the second three-phase electronic switch is connected to the input end of the first three-phase electronic switch, and the other output end is connected to the frequency hopping receiving module. The second mechanical switch is used to transmit the radio frequency signal from the receiving antenna to the first mechanical switch, or to transmit the radio frequency signal from the receiving antenna to the frequency hopping receiving module via the second three-phase electronic switch. The second three-phase electronic switch is used to transmit the cancellation and playback radio frequency signal to the first three-phase electronic switch.

[0018] N-1 two-phase electronic switches are used to receive multi-channel radio frequency signals transmitted by the sampling antenna;

[0019] Where N is the number of channels.

[0020] Further preferably, the frequency hopping receiving module includes: a limiter, a frequency hopping filtering component, a first mixer, a first low-pass filter, a fixed frequency filtering down-conversion component, an ADC and a local oscillator generating module;

[0021] The limiter, the frequency hopping filter component, the first mixer, the first low-pass filter, the fixed-frequency filter down-conversion component and the ADC are connected in sequence;

[0022] The output end of the local oscillator generation module is connected to the first mixer, the fixed frequency filter down-conversion component and the frequency hopping transmission module; the output end of the ADC is connected to the interference cancellation module and the interference perception module;

[0023] The limiter is used to limit the initial RF signal transmitted by the receiving antenna and the sampling antenna module, and output the corresponding RF signal z(t);

[0024] The frequency hopping filter component is used to adaptively filter the radio frequency signal z(t) to remove out-of-band interference of the frequency hopping signal based on the second control instruction, and output the radio frequency signal u(t) after frequency hopping filtering;

[0025] The first mixer is used to mix the radio frequency signal u(t) output after frequency hopping filtering with N frequency hopping local oscillator signals to output a frequency hopping radio frequency signal g(t);

[0026] The first low-pass filter is used to filter out the high-order components generated by mixing in the radio frequency signal g(t) after frequency hopping, and output a low-pass filtered signal v(t);

[0027] The fixed-frequency filtering and down-conversion component is used to filter out the out-of-band interference of the low-pass filtered signal v(t) based on N fixed-frequency local oscillator signals, and output the baseband analog signal b(t) after fixed-frequency filtering and down-conversion;

[0028] The ADC is used to convert the baseband analog signal b(t) into digital form and output the baseband IQ signal.

[0029] The local oscillator generation module is used to generate one frequency hopping local oscillator signal and N frequency hopping local oscillator signals, as well as one fixed-frequency local oscillator signal and N fixed-frequency local oscillator signals.

[0030] Further preferably, the frequency hopping filter assembly includes a low-loss tuned filter, a first three-phase electronic switch, a first low-noise amplifier unit, a high-loss tuned filter, a second three-phase electronic switch, an attenuator, and a second low-noise amplifier unit;

[0031] The output end of the low-loss tuned filter is connected to the input end of the first three-phase electronic switch; one output end of the first three-phase electronic switch is connected to the input end of the first low-noise amplifier unit, and the other output end is connected to the output end of the first low-noise amplifier unit; the output end of the first low-noise amplifier unit is connected to the input end of the high-loss tuned filter; the output end of the high-loss tuned filter is connected to the input end of the second three-phase electronic switch, one output end of the second three-phase electronic switch is connected to the attenuator, and the other output end is connected to the second low-noise amplifier unit;

[0032] The low-loss tuned filter is used to suppress out-of-band interference of the corresponding RF signal z(t) after limiting, and output a low-loss tuned filtered signal z1(t);

[0033] The first three-phase electronic switch is used to select whether the output path of the low-loss tuned filter signal z1(t) is a direct pass or an amplified channel, and output the low-loss tuned filter signal z1(t). The first low-noise amplifier unit is used to perform low-noise amplification processing on the low-loss tuned filter signal z1(t) and output a low-noise amplified signal z2(t).

[0034] The high-loss tuned filter is used to suppress out-of-band interference of the low-noise amplified signal z2(t) or the low-loss tuned filtered signal z1(t), and output the high-loss tuned filtered signal z3(t);

[0035] The second three-phase electronic switch is used to select an output path of the high-loss tuned filtered signal z3(t) as an attenuation channel or an amplification channel, and output the high-loss tuned filtered signal z3(t); the attenuator is used to attenuate the high-loss tuned filtered signal z3(t) and output a radio frequency signal u(t);

[0036] The second low noise amplifier unit is used to perform low noise amplifier processing on the signal z3(t) after high loss tuning and filtering, and output a radio frequency signal u(t).

[0037] Further preferably, the local oscillator generation module includes a high-stability crystal oscillator, a frequency divider, four phase-locked loops, four low-noise amplifier units, four low-pass filters and two splitters;

[0038] A highly stable crystal oscillator is used to generate a local oscillator signal, a frequency divider is used to divide the local oscillator signal into local oscillator signals of different frequencies; a phase-locked loop is used to stabilize the local oscillator signal and optimize its quality; a low-noise amplifier unit is used to perform branch amplitude compensation on the stable local oscillator signal and output the local oscillator signal after low-noise amplification; a low-pass filter is used to perform low-pass filtering on the signal after low-noise amplification; and a splitter is used to divide the low-pass filtered local oscillator signal into multiple local oscillator signals.

[0039] One path of the high-stability crystal oscillator is sequentially connected to the first phase-locked loop, the eleventh low-noise amplifier unit, the eleventh low-pass filter and the first splitter, and outputs N paths of fixed-frequency local oscillator signals;

[0040] The second path of the high-stability crystal oscillator is connected to the second phase-locked loop, the twenty-first low-noise amplifier unit and the twenty-first low-pass filter in sequence, and outputs a fixed-frequency local oscillator signal;

[0041] The three channels of the high-stable crystal oscillator are connected to a frequency divider; the other input end of the frequency divider is connected to a frequency-hopping radio, and its output end is connected to a third phase-locked loop and a fourth phase-locked loop; the third phase-locked loop is connected in sequence to a thirty-first low-noise amplifier unit, a thirty-first low-pass filter, and a second divider, and outputs N frequency-hopping local oscillator signals; the fourth phase-locked loop is connected in sequence to a forty-first low-noise amplifier unit and a forty-first low-pass filter, and outputs one frequency-hopping local oscillator signal.

[0042] Further preferably, the interference cancellation module includes: (N-1)×(K-1) delay units, (N-1)×K weight combining units, two accumulation units and a weight control unit;

[0043] The delay unit is used to perform unit delay on the baseband IQ signal and use pipeline technology to determine the timing matching; the weight combining unit is used to adjust the amplitude and phase of the baseband IQ signal based on the weight signal transmitted by the weight control unit; the accumulation unit is used to perform superposition calculation on the received signal; the weight control unit is used to output each weight signal based on the residual signal;

[0044] The output end of the first accumulator is connected to the frequency hopping transmission module and the weight control unit, and is used to receive the first digital signal in the baseband IQ signal; the first weight combining unit and the first delay unit input the second digital signal in the baseband IQ signal; an input end of the first weight combining unit is connected to the weight control unit, and an output end thereof is connected to the second accumulator; the output end of the first delay unit is connected to the second delay unit and the second weight combining unit; and so on, the input end of the Kth weight combining unit is connected to the K-1th delay unit and the weight control unit, and the output end is connected to the second accumulator;

[0045] By analogy, the (N-1)×(K-1)+1th weight combining unit and the (N-2)×(K-1)+1th delay unit input the Nth digital signal in the baseband IQ signal; the other input end of the (N-1)×(K-1)+1th weight combining unit is connected to the weight control unit, and the output end is connected to the second accumulator unit; the output end of the (N-2)×(K-1)+1th delay unit is connected to the (N-2)×(K-1)+2th delay unit and the (N-1)×(K-1)+2th weight combining unit; similarly, the input end of the (N-1)×K weight combining unit is the (N-1)×(K-1)th delay unit and the weight control unit, and the output end is connected to the second accumulator unit;

[0046] Where K is the number of time domain filter taps.

[0047] On the other hand, the present application provides a method for canceling interference of an ultra-short wave frequency hopping radio station, comprising the following steps:

[0048] Step 1: Based on the first control instruction, the switch is switched to select whether to transmit the RF signal from the receiving antenna to the frequency hopping radio, thereby terminating the current execution; or the initial RF signal is transmitted to the frequency hopping receiving module, thereby proceeding to step 2; wherein the first control instruction is used to control the RF switch state; the initial RF signal includes the multi-channel RF signal output by the sampling antenna module and the RF signal output by the receiving antenna;

[0049] Step 2: Based on the second control instruction, perform out-of-band filtering and down-conversion processing on the initial RF signal to obtain a baseband IQ signal; wherein the second control instruction is used to control the acquisition of the frequency hopping receiving local oscillator;

[0050] Step 3: Based on the third control instruction, perform interference signal suppression on the baseband IQ signal and output a residual signal after interference cancellation processing; wherein the third control instruction is used to control the parameters of the interference cancellation algorithm;

[0051] Step 4: Based on the baseband IQ signal, output an interference perception indication signal, and combine the frequency word information of the frequency hopping radio to obtain the first control instruction, the second control instruction, the third control instruction, and the fourth control instruction;

[0052] Step 5: Based on the fourth control instruction, up-convert the residual signal and output the cancellation playback RF signal to transmit to the RF switch module; wherein the fourth control instruction is used to control the acquisition of the frequency hopping transmission local oscillator;

[0053] Step 6: Transmit the cancellation playback RF signal to the frequency hopping radio through the RF switch module.

[0054] Further preferably, step 2 specifically includes the following steps:

[0055] Step 2.1: Limit the initial RF signal transmitted by the receiving antenna and the sampling antenna module, and output the corresponding RF signal z(t);

[0056] Step 2.2: Based on the second control instruction, adaptively filter the RF signal z(t) to remove out-of-band interference of the frequency hopping signal, and output the RF signal u(t) after the frequency hopping filtering;

[0057] Step 2.3: Mix the RF signal u(t) output after the frequency hopping filter with the N-channel frequency hopping local oscillator signals to output the frequency hopping RF signal g(t);

[0058] Step 2.4: Filter out the high-order components generated by mixing in the RF signal g(t) after frequency hopping, and output the low-pass filtered signal v(t);

[0059] Step 2.5: Based on the N fixed-frequency local oscillator signals, filter out-of-band interference from the low-pass filtered signal v(t) and output the fixed-frequency filtered down-converted baseband analog signal b(t);

[0060] Step 2.6: Perform analog-to-digital conversion on the baseband analog signal b(t) and output a baseband IQ signal.

[0061] Further preferably, the method for obtaining the residual signal by interference cancellation in step 3 includes the following steps:

[0062] Step 3.1: Initialize the weights and establish an interference cancellation model based on pipeline technology;

[0063] Step 3.2: Calculate and update the weights based on the minimum mean square error (MMSE) criterion.

[0064] Step 3.3: Accumulate and calculate the interference extraction signal based on the updated weights;

[0065] Step 3.4: Subtract the interference extraction signal from the RF signal transmitted by the receiving antenna to obtain a residual signal after interference cancellation processing.

[0066] Further preferably, the method for obtaining the interference perception indication signal in step 4 is:

[0067] Step 4.1: Based on the working mechanism of the frequency-hopping radio, the baseband IQ signal stream is segmented, and each segment corresponds to the interference state at the current moment;

[0068] Step 4.2: Extract typical features of the intercepted data to alleviate data stream accumulation; the typical features include time domain information and frequency domain information;

[0069] Step 4.3: Based on the kernel mapping network parameters and boundary parameters, project the representative eigenvalues ​​to the kernel mapping network;

[0070] Step 4.4: Calculate the decision value of the current data segment in the core mapping network space, compare it with the offline learned decision threshold, determine whether interference exists, and obtain the interference perception indication signal.

[0071] Further preferably, the parameter optimization method of the sampling antenna module includes the following steps:

[0072] Obtain the operating frequency band and number of sampling antennas based on the interference scenario of the frequency hopping radio station;

[0073] The blind zone cancellation model is established by taking the different interference directions and working frequency bands that cannot pass after cancellation as the cancellation blind zone;

[0074] Based on the minimum blind spot model, determine the distance between the receiving antenna and the sampling antenna, as well as the gain of the sampling antenna.

[0075] Further preferably, step 1 is specifically as follows:

[0076] Analyze the transmission and reception status of the frequency hopping radio. When the frequency hopping radio is in the transmitting state, the switch of the RF switch module is switched to enable direct communication between the frequency hopping radio and the receiving antenna. When the frequency hopping radio is in the receiving state, the switch of the RF switch module is switched to the cancellation state so that the frequency hopping receiving module can receive the initial RF signal and down-convert it into a baseband signal.

[0077] In general, the above technical solutions conceived by this application have the following beneficial effects compared with the existing technologies:

[0078] The present application provides an ultra-short wave frequency hopping radio interference cancellation device, which fully utilizes the cooperative frequency replacement mechanism of the ultra-short wave frequency hopping radio and adopts a ping-pong switching method to achieve ultra-high-speed frequency switching and link establishment. More specifically, before the frequency switching, the device has prepared the radio frequency link of the next hop signal. When the enable signal arrives, the link can be successfully established within 1us, providing a basis for the robustness of the interference protection performance.

[0079] The present application provides an ultra-short wave frequency hopping radio interference cancellation device, in which a frequency hopping filter component is used to set up a multi-stage radio frequency filter, namely a low-loss tuned filter and a high-loss tuned filter. At the same time, a narrowband filter structure (bandpass filter) is also designed in the fixed-frequency filter downconversion component, which can achieve extremely high out-of-band suppression performance (exceeding 110dB suppression ratio) and avoid the influence of complex electromagnetic environment on interference protection performance.

[0080] The present application provides an ultra-short wave frequency hopping radio interference cancellation device, in which the frequency hopping receiving module adopts multi-stage detection (i.e., the first detection point and the second detection point in the frequency hopping filtering module), and adjusts the signal size through the corresponding electronic switch to ensure the reception of ultra-high and ultra-low in-band signals under large out-of-band interference conditions; at the same time, a hysteresis control method is adopted, that is, a buffer zone of the switch switching threshold can be set, and the switch state is switched only when the radio frequency signal changes greatly. The link transmission remains unchanged within a certain range of fluctuations, and the link automatic gain adjustment is completed to achieve large dynamic and high-sensitivity reception.

[0081] The present application provides a method for canceling interference in an ultra-short wave frequency-hopping radio station, wherein the interference cancellation module combines the working mechanism of the frequency-hopping radio station and the interference cancellation algorithm parameter optimization theory to achieve rapid convergence of the cancellation weights, that is, weight search and rapid convergence are performed before the frequency-hopping signal is transmitted. At this time, only the interference signal remains, and the optimal weight converges fastest; after the frequency-hopping signal is transmitted, the optimal weight is maintained to achieve rapid interference suppression, greatly reducing the impact of interference on the frequency-hopping radio communication.

[0082] The present application provides an ultra-short wave frequency hopping radio interference cancellation device, in which the interference cancellation module, based on the explanation of the influence mechanism of interference multipath on the cancellation performance, makes full use of the differences between the interference signal and the communication signal in the space, time, frequency and other domains, and proposes a multi-domain fusion interference cancellation algorithm to achieve a high cancellation ratio and improve the interference protection capability.

[0083] In the ultra-short wave frequency hopping radio interference cancellation device provided in this application, the interference cancellation module adopts retiming and pipeline technology to shorten the critical path length, optimize the FPGA hardware implementation structure, and achieve a data throughput of up to 200Msps, breaking through the limitation of the longer critical path on the algorithm running speed and strongly supporting the high-speed implementation of the multi-domain fusion interference cancellation algorithm.

[0084] The present application provides a lightweight method for perceiving interference from ultra-short wave frequency-hopping radio stations. Traditional methods detect interference after the frequency-hopping radio station transmits. At this time, signals are mixed in the interference, making detection extremely difficult and complex. The interference perception module in the present application combines the working mechanism of the frequency-hopping radio station to propose a low-complexity interference perception algorithm. Similarly, interference is perceived before the frequency-hopping radio station transmits. At this time, the received signal contains only interference, and simple feature discrimination is sufficient, which greatly reduces the response time of the device to interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0085] Figure 1 Schematic diagram of an ultra-short wave frequency hopping radio interference cancellation device provided in an embodiment of the present application;

[0086] Figure 2 This is an overall schematic diagram of the radio frequency switch module provided in an embodiment of the present application;

[0087] Figure 3 This is a schematic diagram of a frequency hopping receiving module provided in an embodiment of the present application;

[0088] Figure 4 This is a schematic diagram of a frequency hopping filter component provided in an embodiment of the present application;

[0089] Figure 5 This is a schematic diagram of a fixed-frequency filtering down-conversion component provided in an embodiment of the present application;

[0090] Figure 6 Schematic diagram of a local oscillator generating unit provided in an embodiment of the present application;

[0091] Figure 7 Schematic diagram of the interference cancellation module provided in an embodiment of the present application;

[0092] Figure 8 This is a flowchart of the interference perception module processing provided by an embodiment of the present application;

[0093] Figure 9 This is an interference perception classification effect diagram provided by an embodiment of the present application;

[0094] Figure 10 This is a logic flow chart of the display control module provided by an embodiment of the present application;

[0095] Figure 11 This is a schematic diagram of a frequency hopping transmission module provided in an embodiment of the present application;

[0096] FIG12( a ) is a spectrum diagram of a UHF frequency hopping radio station subjected to broadband blocking interference provided by an embodiment of the present application;

[0097] FIG12( b ) is a spectrum diagram of the ultra-short wave frequency hopping radio station after interference protection provided by an embodiment of the present application. DETAILED DESCRIPTION

[0098] In order to make the purpose, technical solution and specific implementation of this application clearer, the specific implementation steps of the present invention are further described in detail below with reference to the accompanying drawings. It should be understood that the specific implementation cases described here are only used to explain the present invention and are not intended to limit this application.

[0099] To address the problems of poor anti-blocking capability, long convergence time, and large delay in interference suppression in existing anti-blocking reception and digital interference cancellation schemes, this application provides a device for ultra-shortwave frequency-hopping radio interference cancellation. This device is characterized by fully integrating the ultra-shortwave frequency-hopping radio communication mechanism to achieve ultra-high-speed frequency switching and link establishment, high out-of-band suppression, and high-sensitivity and large-dynamic RF reception. On this basis, the interference cancellation algorithm structure is optimized to improve the cancellation ratio and convergence speed, resolving the existing problems of poor environmental adaptability and large delay in suppressing various intentional and unintentional interference situations. At the same time, a low-complexity interference perception algorithm significantly reduces the device's response time to interference.

[0100] More specifically, the present application provides an ultra-short wave frequency hopping radio interference cancellation device to solve the problem of interference protection of ultra-short wave frequency hopping radio in an electromagnetic countermeasure environment. First, the out-of-channel interference is filtered out by frequency hopping and fixed-frequency filters. Then, under the action of frequency hopping or fixed-frequency local oscillators, the same-frequency interference and communication signals in the channel are converted into fixed-frequency baseband signals, and then the interference cancellation algorithm is used to suppress the same-frequency interference. When the directions of the interference and communication signals are unknown, the device can use the characteristics of the interference signal to accurately suppress the interference on the antenna array pattern to maintain the integrity of the communication signal. The present application realizes high-suppression out-of-band filtering and large dynamic and high-sensitivity frequency hopping reception in the radio frequency domain, and completes interference cancellation in the digital domain. It has the characteristics of fast cancellation speed, small delay, and strong anti-interference ability. After experimental verification, this interference cancellation device can improve the anti-interference capability of a certain type of ultra-short wave frequency hopping radio by 30dB, and has a good application prospect in radio communication anti-interference.

[0101] like Figure 1 As shown, the present application provides an ultra-short wave frequency hopping radio interference cancellation device, comprising: a radio frequency switch module 01, a frequency hopping receiving module 02, an interference cancellation module 03, an interference sensing module 04, a display control module 05, a frequency hopping transmitting module 06 and a sampling antenna module 07;

[0102] The input end of the RF switch module 01 is provided with a receiving antenna and a sampling antenna module 07, and the input end is connected to the display control module and the frequency hopping transmission module. The output end is connected to the RF receiving module 02 and the RF port of the frequency hopping receiving radio station. The RF switch module 01 is used to receive the RF signal x(t) transmitted by the receiving antenna and the sampling antenna module, the cancellation playback signal y(t) of the frequency hopping transmission module, and the control instruction SW transmitted by the display control module 05, and realizes the switching of the direct or access state by switching the switch. The output end outputs the RF signal x(t) switched by the switch.

[0103] The input end of the frequency hopping receiving module 02 is connected to the RF switch module 01 and the display control module 05 respectively, and the output end is connected to the interference cancellation module, the interference perception module and the frequency hopping transmitting module; it is used to receive the RF signal x(t) after switching by the RF switch module and the control instruction SW of the display control module 05, and obtain the baseband IQ signal x through out-of-band filtering and down-conversion processing. I (n) and x Q (n);

[0104] The input end of the interference cancellation module 03 is connected to the frequency hopping receiving module 02 and the display control module 05, and the output end is connected to the frequency hopping transmitting module 06; it is used to receive the baseband IQ signal x converted by the frequency hopping receiving module 02 I (n) and x Q (n) and the instruction SW output by the display control module, outputting the residual signal e(n) after cancellation processing to achieve the suppression of interference signals;

[0105] The input end of the interference sensing module 04 is connected to the frequency hopping receiving module 02, and the output end is connected to the display control module 05, which is used to receive the baseband IQ signal x converted by the frequency hopping receiving module 02. I (n) and x Q (n), outputs the interference indication flag to realize interference signal perception;

[0106] The input end of the display control module 05 is connected to the interference perception module 04, and the output end is connected to the RF switch module 01, the frequency hopping receiving module 02, the interference cancellation module 03 and the frequency hopping transmitting module 06; it is used to receive the perception indication Flag of the interference perception module 04 and the frequency word information of the ultra-short wave frequency hopping radio station, and output the control instruction SW, which is used to control the RF switch state, the frequency hopping receiving local oscillator, the interference cancellation algorithm parameters and the frequency hopping transmitting local oscillator;

[0107] The input end of the frequency hopping transmission module 06 is connected to the interference cancellation module 03, the display control module 05 and the frequency hopping reception module 02, and the output end is connected to the RF switch module 01; it is used to receive the residual signal e(n) after cancellation by the interference cancellation module 03 and the control instruction SW transmitted by the display control module 05, and output the simulated playback RF signal y(t) after up-conversion to achieve signal playback;

[0108] The output end of the sampling antenna module 07 is connected to the radio frequency switch module 01 for outputting the radio frequency signal x(t) to provide multi-channel signal reception in addition to the receiving antenna.

[0109] More preferably, Figure 2As shown, the RF switch module 01 is composed of a first mechanical switch 011, a second mechanical switch 012, a first three-phase electronic switch 013, a second three-phase electronic switch 014, and N-1 two-phase electronic switches (015, 016, ...); the input end of the first mechanical switch 011 is connected to the second mechanical switch 012 and the first three-phase electronic switch 013, and its input end is the receiving antenna signal x1(t) or the cancellation playback RF signal y(t), and is output to the frequency hopping radio; the input signal of the second mechanical switch 012 is the receiving antenna signal x1(t), and the output end is connected to the first mechanical switch 011 and the second three-phase electronic switch 014, and its output The output is a radio frequency signal x1(t), which is used to control the flow direction of the radio frequency signal; the input end of the first three-phase electronic switch 013 is connected to the frequency hopping transmission module 06 and the second three-phase electronic switch 014, and its output end is connected to the first mechanical switch 011, which inputs the receiving antenna signal x1(t) or the cancellation and playback radio frequency signal y(t), and outputs the switch-selected receiving antenna signal x1(t) or the cancellation and playback radio frequency signal y(t); the input and output of the second three-phase electronic switch 014 are both the receiving antenna signal x1(t), which is used to control the flow direction of the radio frequency signal; the input end of the two-phase electronic switch receives the various receiving signals x2(t) to x3(t) output by the sampling antenna module. N (t), the output end is used to control the incoming and outgoing receiving signals, thereby connecting / cutting off the receiving signal of the sampling antenna module;

[0110] More preferably, Figure 3 As shown, the frequency hopping receiving module 02 includes: a limiter 021, a frequency hopping filter component 022, a first mixer 023, a first low-pass filter 024, a fixed-frequency filter down-conversion component 025, an ADC 026, and a local oscillator generation module 027; the input end of the limiter 021 is connected to the receiving antenna and the sampling antenna, and the output end is connected to the frequency hopping filter component 022; it is used to receive the RF signals x1(t)~x1(t) transmitted by the receiving antenna and the sampling antenna. N(t) outputting the corresponding radio frequency signal z(t) after limiting; the input end of the frequency hopping filter component 022 is connected with the limiter 021 and the local oscillator generation module 027, and the output end is connected with the first frequency mixer 023; the frequency hopping filter component 022 is used for receiving the radio frequency signal z(t) after limiting and the frequency word signal SW, outputting the radio frequency signal u(t) after frequency hopping filtering, so as to realize adaptive filtering of out-of-band interference of the frequency hopping signal; the input end of the first frequency mixer 023 is connected with the frequency hopping filter component and the local oscillator generation module, and the output end is connected with the low-pass filter, which is used for mixing the radio frequency signal u(t) outputted after frequency hopping filtering and the frequency hopping local oscillator signal ft1, outputting the radio frequency signal g(t) after frequency hopping, so as to generate a fixed intermediate frequency signal; the output end of the first low-pass filter is connected with the fixed frequency filtering down-conversion component 025, which is used for filtering the high-order component generated by mixing, and outputting the low-pass filtered signal v(t); the input end of the fixed frequency filtering down-conversion component 025 is connected with the first low-pass filter 024 and the local oscillator generation module 027, and the output end is connected with the ADC 026, which is used for further filtering the low-pass filtered signal v(t) to remove the out-of-band interference of the communication, and outputting the baseband analog signal b(t) after fixed frequency filtering down-conversion; the output end of the ADC 026 is connected with the interference cancellation module 03 and the interference perception module 04, which is used for converting the baseband analog signal b(t) into a digital signal, and outputting the baseband digital signal x I (n), x Q (n); the input end of the local oscillator generation module 027 is connected with the radio frequency word interface, and the output end is connected with the frequency hopping filter component 022, the first frequency mixer 023, the fixed frequency filtering down-conversion component 025 and the radio frequency transmitting module 06; the local oscillator generation module 027 is used for receiving the frequency word signal SW, generating the first frequency hopping local oscillator signal ft1 and the second frequency hopping local oscillator signal ft2, and the first fixed frequency local oscillator signal fc1 and the second fixed frequency local oscillator signal fc2;

[0111] As shown in Figure 4 , the frequency hopping filter component 022 includes a low-loss tuning filter 0221, a first three-phase electronic switch 0222, a first low-noise amplification unit 0223, a high-loss tuning filter 0224, a second three-phase electronic switch 0225, an attenuator 0226 and a second low-noise amplification unit 0227.

[0112] The input end of the low-loss tuning filter 0221 is connected with the limiter 021 and the ultra-short wave frequency hopping radio station, and the output end is connected with the first low-noise amplification unit 0222 and the first detection point 1, which is used for receiving the corresponding radio frequency signal z(t) after limiting and the frequency word signal SW, preliminarily suppressing the out-of-band interference, and outputting the low-loss tuning filter signal z1(t);

[0113] The input end of the first three-phase electronic switch 0222 is connected to the low insertion loss tuned filter 0221, and the output end is connected to the high insertion loss tuned filter 0224 and the first low noise amplifier unit 0223. It is used for gating the signal z1(t) after the low insertion loss tuned filtering, ensuring high reliability of both high and low signal reception. The gated output signal remains unchanged and is still z1(t).

[0114] The output end of the first low noise amplifier unit 0223 is connected to the high-loss tuned filter 0224, which is used to perform low noise amplification on the low-loss tuned filtered signal z1(t) and output the low noise amplified signal z2(t), so as to optimize the link noise system under low signal-to-noise ratio conditions;

[0115] The input end of the high-loss tuned filter 0224 is connected to the first low-noise amplifier unit 0223 and the ultra-short wave frequency hopping radio, and the output end is connected to the first mixer 023 and the second detection point 2. It is used to receive the low-noise amplified signal z2(t) and the frequency word signal SW, further suppress out-of-band interference, and output the high-loss tuned filtered signal z3(t);

[0116] The input end of the second three-phase electronic switch 0225 is connected to the high insertion loss tuned filter 0224, and the output end is connected to the attenuator 0226 and the second low noise amplifier unit 0227. It is used for gating the high insertion loss tuned filtered signal z3(t) to achieve high reliability reception of in-band signals under high out-of-band interference. The gated output signal remains unchanged and is still z3(t).

[0117] The input end of the attenuator 0226 is connected to the second three-phase electronic switch 0225, and the output end is connected to the mixer 023, which is used to attenuate and adjust the high insertion loss tuned filtered signal z3(t) to ensure normal reception of the ultra-high signal-to-noise ratio downlink. The output signal is u(t);

[0118] The input end of the first low-noise amplifier unit 0227 is connected to the second three-phase electronic switch 0225, and the output end is connected to the mixer 023. It is used to perform low-noise amplification processing on the low-loss tuned filter signal z3(t), and the output signal is z2(t), so as to achieve link noise optimization under ultra-low signal-to-noise ratio conditions;

[0119] like Figure 5 As shown, the fixed frequency filtering down-conversion component 025 includes a third low noise amplifier unit 0251, a second mixer 0252 and a bandpass filter 0253;

[0120] The input end of the third low noise amplifier LNA 0251 is connected with the low pass filter 024, and the output end is connected with the second mixer 0252, which is used for noise optimization and loss compensation of the low pass filtered radio frequency signal v(t), and outputs the low noise amplifier output signal v1(t); the input end of the second mixer 0252 is connected with the local oscillator generation module 027 and the third low noise amplifier unit 0251, and the output end is connected with the band pass filter 0253, which is used for down conversion processing of the low noise amplifier output signal v1(t) in combination with the fixed local oscillator signal f c1, and outputs the down conversion signal v2(t); the input end of the band pass filter is connected with the second mixer 0252, and the output end is connected with the ADC 026, which is used for deep suppression of the communication out-of-band interference of the down conversion signal v2(t), and outputs the narrow band filtered signal b(t);

[0121] As shown in Figure 6 , the local oscillator generation module 027 includes a high-stability crystal oscillator 0271, a frequency divider 0272, four phase-locked loops 0273, four low noise amplifier units 0274, four low pass filters 0275, and two shunters 0276;

[0122] One way of the high-stability crystal oscillator 0271 passes through the first phase-locked loop 0273a, the eleventh low noise amplifier unit 0274a, the eleventh low pass filter 0275a, and the first shunter 0276a in turn, and outputs N fixed frequency local oscillator signals f C1 ; the second way of the high-stability crystal oscillator 0271 passes through the second phase-locked loop 0273b, the twenty-first low noise amplifier unit 0274b, and the twenty-first low pass filter 0275b in turn, and outputs one fixed frequency local oscillator signal f C2 ; the third way of the high-stability crystal oscillator 0271 is connected with the frequency divider 0272, the input end of the frequency divider 0272 is connected with the ultra-short wave frequency hopping radio station and the high-temperature crystal oscillator 0271, and the output end is connected with the third phase-locked loop 0273c and the fourth phase-locked loop 0273d; the third phase-locked loop 0273c passes through the thirty-first low noise amplifier unit 0274c, the thirty-first low pass filter 0275c, and the second shunter 0276b, and outputs N frequency hopping local oscillator signals f t1 ; the fourth phase-locked loop 0273d passes through the forty-first low noise amplifier unit 0274d and the forty-first low pass filter 0275d, and outputs one frequency hopping local oscillator signal f t2 ;

[0123] Among them, the high-stability crystal oscillator 0271 is used to generate a local oscillator signal; the frequency divider is used to divide the local oscillator signal into local oscillator signals of different frequencies; the phase-locked loop is used to stabilize the local oscillator signal and optimize the quality of the local oscillator signal; the low noise amplifier unit is used to compensate the amplitude of the stabilized local oscillator signal, and output the low noise amplifier output signal; the low pass filter is used to low pass filter the low noise amplifier output signal; the shunter is used to divide the low pass filtered local oscillator signal into multiple local oscillator signals.

[0124] Further preferably, as Figure 7 As shown, the interference cancellation module 03 includes (N-1)×(K-1) delay units 031, (N-1)×K weight combining units 032, 2 accumulation units 033 and a weight control unit 034;

[0125] The first accumulating unit 033a inputs the first digital signal x1(n), and its output is connected to the frequency hopping transmitting module 06 and the weight control unit 034; the second digital signal x2(n) is input to the first weight combining unit 032a and the first delay unit 031a; the other input of the first weight combining unit 032a is connected to the weight control unit 034, and its output is connected to the second accumulating unit 033b; the output of the first delay unit 031a is connected to the second delay unit 031b and the second weight combining unit 032b; similarly, the output of the K-1th delay unit 031c is connected to the K-th weight combining unit 032d, the input of the K-1th weight combining unit 032d is connected to the K-1th delay unit 031c and the weight control unit 034, and its output is connected to the second accumulating unit 033b; and so on. N (n) is input to the (N-1)×(K-1)+1th weight merging unit 032e and the (N-2)×(K-1)+1th delay unit 031d; the other input end of the (N-1)×(K-1)+1th weight merging unit 032e is connected to the weight control unit 034, and the output end is connected to the second accumulating unit 033b; the output end of the (N-2)×(K-1)+1th delay unit 031d is connected to the (N-2)×(K-1)+1th weight merging unit 032e. -1)+2 delay unit 031e and the (N-1)×(K-1)+2th weight merging unit 032f; similarly, the output end of the (N-1)×(K-1)th delay unit 031f is connected to the (N-1)×Kth weight merging unit 032h, the input end of the weight merging unit 032h is the (N-1)×(K-1)th delay unit 031f and the weight control unit 034, and the output end is connected to the second accumulator unit 033b.

[0126] Among them, the output of the delay unit is the unit delay of the input signal, which is used for timing matching achieved by pipeline technology; the weight merging unit inputs the weight signal transmitted by the weight control unit and the corresponding baseband signal to adjust the amplitude and phase of the baseband signal; the accumulation unit is used to superimpose the input signal; the weight control unit is used to output each control weight signal based on the interference cancellation residual signal e(n).

[0127] Further preferably, the interference cancellation algorithm in the interference cancellation module 03 includes the following steps:

[0128] Step S31: Initialize weight w = [0, ... 0] T,At this time, the output signal e(n)=x1(n), and the interference cancellation model is established based on the pipeline technology;

[0129] Step S32: Based on the minimum mean square error MMSE criterion min{||e(n)|| 2}, the weight control unit 034 in the interference cancellation module 03 completes the weight calculation and update;

[0130] Step S33: Accumulate and calculate the interference extraction signal based on the updated weights: y(n)=w2×x2(n)+…+w N ×x N (n);

[0131] Step S34: Subtract the interference extraction signal from the receiving antenna signal to obtain a useful communication signal (cancellation output signal): e(n)=x1(n)-y(n);

[0132] More preferably, Figure 8 As shown, the interference perception process in the interference perception module 04 includes the following steps:

[0133] Step S41: Combined with the working mechanism of the ultra-short wave frequency hopping radio, the digital baseband signal stream is segmented and intercepted. Each segment corresponds to the interference state at the current moment. The ultra-short wave frequency hopping radio working gap segment x can be selected. d (n);

[0134] Step S42: Through empirical value or modeling analysis, extract typical features of the intercepted data to alleviate data stream accumulation; wherein, typical features include: time domain information, frequency domain information and other features, such as mean E = 1 / D × ∑x d (n), variance V = 1 / D × ∑ (x d (n)-E) 2 etc.; where D is the number of segments;

[0135] Step S43: Project the typical eigenvalues ​​to the kernel mapping network through the kernel mapping network parameters and boundary parameters learned from offline data; specifically, establish the kernel mapping space: Φ: x i →φ(x i ), the distance between samples is: K(x i ,x j )=exp(-||x i -x j || 2 / σ), build a classification model:

[0136] max{∑α i K(x i ,x i )-∑∑α i αj K(x i ,x j )},st∑α i =1

[0137] The model parameters {σ, α, R} are obtained by offline data training, where R is the boundary threshold; φ(x i ) is the kernel mapping function; σ is the Gaussian kernel parameter; α is the Lagrange coefficient;

[0138] Step S44: Calculate the decision value of the current data segment in the core mapping network space, compare it with the offline learned decision threshold, determine whether there is interference, and issue a corresponding control instruction;

[0139] More specifically, according to the discriminant function f(x i )=R 2 -||φ(x i )-φ(x j )|| 2 Determine whether there is interference.

[0140] Figure 9 The diagram shows the characteristic distribution and classification of the segmented data of a certain ultra-short wave frequency hopping radio station. Figure 9 The results are the experimental test results of the ultra-short wave frequency hopping radio interference cancellation device in the confrontation scenario, among which the interference patterns include more than ten patterns such as noise FM, BPSK and single tone. It can be seen that the interference perception method has good robustness in identifying different types of interference.

[0141] Combine Figure 10 As shown, the display control module 05 includes the following steps:

[0142] Step S51: Initialize hardware parameters, start interference perception and judgment, and wait for command input; the hardware parameters include but are not limited to: center frequency, bandwidth, sampling frequency, and intermediate frequency difference;

[0143] Step S52: After receiving the instruction, determine the instruction type. When receiving the parameter setting instruction, if automatic is selected, all parameters of the device are automatically analyzed, and the switch state is automatically switched according to the interference state; if manual is selected, it is necessary to manually set the device's working mode, cancellation method, working frequency and other parameters; set the interference cancellation device parameters, and if a bypass or cancellation instruction is received, switch to the corresponding state through the RF switch module; when receiving an interference or no interference instruction, if there is no interference, the device switches to bypass mode, and if there is interference, it switches to cancellation mode; repeat step S52 until it stops working.

[0144] like Figure 11As shown, the RF transmission module 06 includes a DAC 061, a mixer 062, a low-pass filter 063, a mixer 064 and a tuned filter 065 connected in sequence; the input end of the DAC 061 is connected to the interference cancellation module 03, and the output end is connected to the mixer 062, for performing digital-to-analog conversion on the interference cancellation residual signal e(n) and outputting an analog signal e(t); the other input end of the mixer 062 is connected to the local oscillator generation module 027, and the output end is connected to the low-pass filter 063, for combining the fixed-frequency local oscillator signal f C2 , up-convert the analog signal e(t) and output the up-converted signal q(t); the input end of the low-pass filter 063 is connected to the mixer 062, and the output end is connected to the mixer 064, which is used to filter out the high-frequency components generated by mixing in the up-converted signal q(t), and output the low-pass filtered playback signal l(t); the input end of the mixer 064 is connected to the local oscillator generation module 027 and the low-pass filter 063, and the output end is connected to the tuned filter 065, which is used to combine the frequency hopping local oscillator signal to perform frequency calibration on the filtered playback signal l(t) and output the mixed signal h(t); the input end of the tuned filter 065 is connected to the mixer 064 and the ultra-short wave frequency hopping radio, and the output end is connected to the radio frequency switch module 01, which is used to filter out the out-of-band signal generated by mixing from the mixed signal h(t) based on the frequency word signal SW, and obtain the cancellation playback signal y(t);

[0145] Furthermore, the array parameter optimization method of the sampling antenna module 07 includes the following steps:

[0146] Step S71: obtaining the operating frequency band and number of sampling antennas according to the interference scenario of the ultra-short wave frequency hopping radio station;

[0147] Step S72: establishing a blind spot cancellation model based on the different interference directions and working frequency bands that cannot pass through after cancellation as cancellation blind spots;

[0148] Step S73: Based on the minimum blind area model, determine the distance between the receiving antenna and the sampling antenna, and the gain of the sampling antenna.

[0149] Figures 12(a) and 12(b) show the signal spectrum of a certain ultra-short wave frequency hopping radio after being subjected to broadband suppression interference @JSR=25+dB and the signal spectrum after cancellation; Figures 12(a) and 12(b) are the actual test results of the ultra-short wave frequency hopping radio interference cancellation device in a confrontation scenario. It can be seen that the communication of the ultra-short wave frequency hopping radio is interrupted after being subjected to broadband suppression interference. If the interference protection method proposed in this application is adopted, the interference threshold of the frequency hopping communication system is increased by more than 25dB.

[0150] In summary, compared with the prior art, this application has the following advantages:

[0151] The present application provides an ultra-short wave frequency hopping radio interference cancellation device, which fully utilizes the cooperative frequency replacement mechanism of the ultra-short wave frequency hopping radio and adopts a ping-pong switching method to achieve ultra-high-speed frequency switching and link establishment. More specifically, before the frequency switching, the device has prepared the radio frequency link of the next hop signal. When the enable signal arrives, the link can be successfully established within 1us, providing a basis for the robustness of the interference protection performance.

[0152] The present application provides an ultra-short wave frequency hopping radio interference cancellation device, in which a frequency hopping filter component is used to set up a multi-stage radio frequency filter, namely a low-loss tuned filter and a high-loss tuned filter. At the same time, a narrowband filter structure (bandpass filter) is also designed in the fixed-frequency filter downconversion component, which can achieve extremely high out-of-band suppression performance (exceeding 110dB suppression ratio) and avoid the influence of complex electromagnetic environment on interference protection performance.

[0153] The present application provides an ultra-short wave frequency hopping radio interference cancellation device, in which the frequency hopping receiving module adopts multi-stage detection (i.e., the first detection point and the second detection point in the frequency hopping filtering module), and adjusts the signal size through the corresponding electronic switch to ensure the reception of ultra-high and ultra-low in-band signals under large out-of-band interference conditions; at the same time, a hysteresis control method is adopted, that is, a buffer zone of the switch switching threshold can be set, and the switch state is switched only when the radio frequency signal changes greatly. The link transmission remains unchanged within a certain range of fluctuations, and the link automatic gain adjustment is completed to achieve large dynamic and high-sensitivity reception.

[0154] The present application provides a method for canceling interference in an ultra-short wave frequency-hopping radio station, wherein the interference cancellation module combines the working mechanism of the frequency-hopping radio station and the interference cancellation algorithm parameter optimization theory to achieve rapid convergence of the cancellation weights, that is, weight search and rapid convergence are performed before the frequency-hopping signal is transmitted. At this time, only the interference signal remains, and the optimal weight converges fastest; after the frequency-hopping signal is transmitted, the optimal weight is maintained to achieve rapid interference suppression, greatly reducing the impact of interference on the frequency-hopping radio communication.

[0155] The present application provides an ultra-short wave frequency hopping radio interference cancellation device, in which the interference cancellation module, based on the explanation of the influence mechanism of interference multipath on the cancellation performance, makes full use of the differences between the interference signal and the communication signal in the space, time, frequency and other domains, and proposes a multi-domain fusion interference cancellation algorithm to achieve a high cancellation ratio and improve the interference protection capability.

[0156] In the ultra-short wave frequency hopping radio interference cancellation device provided in this application, the interference cancellation module adopts retiming and pipeline technology to shorten the critical path length, optimize the FPGA hardware implementation structure, and achieve a data throughput of up to 200Msps, breaking through the limitation of the longer critical path on the algorithm running speed and strongly supporting the high-speed implementation of the multi-domain fusion interference cancellation algorithm.

[0157] The present application provides a lightweight method for perceiving interference from ultra-short wave frequency-hopping radio stations. Traditional methods detect interference after the frequency-hopping radio station transmits. At this time, signals are mixed in the interference, making detection extremely difficult and complex. The interference perception module in the present application combines the working mechanism of the frequency-hopping radio station to propose a low-complexity interference perception algorithm. Similarly, interference is perceived before the frequency-hopping radio station transmits. At this time, the received signal contains only interference, and simple feature discrimination is sufficient, which greatly reduces the response time of the device to interference.

[0158] It should be understood that expressions such as “include” and “may include” used in the present application indicate the existence of disclosed functions, operations, or constituent elements, and do not limit one or more additional functions, operations, and constituent elements.

[0159] In the description of the embodiments of the present application, it should be noted that, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium.

[0160] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A device for canceling interference of ultra-short wave frequency hopping radio stations, characterized in that: include: The sampling antenna module is used to output a multi-channel initial RF signal, which together with the simulated initial RF signal output by the receiving antenna constitutes an initial RF signal; A radio frequency switch module, having a receiving antenna and a sampling antenna provided at its input end, its input end connected to the frequency hopping transmitting module, and its output end connected to the radio frequency receiving module and the frequency hopping radio, for transmitting the radio frequency signal from the receiving antenna to the frequency hopping radio through switch switching based on a first control instruction; Or transmit the initial RF signal to the frequency hopping receiving module, and transmit the playback RF signal to the frequency hopping radio; A frequency hopping receiving module, whose output end is connected to the interference cancellation module, the interference sensing module and the frequency hopping transmitting module, is used to perform out-of-band filtering and down-conversion processing on the initial RF signal based on the second control instruction to obtain a baseband IQ signal; An interference cancellation module, whose output end is connected to the frequency hopping transmission module, is used to suppress the interference signal of the baseband IQ signal based on the third control instruction and output the residual signal after the cancellation processing; An interference perception module is configured to output an interference perception indication signal based on a baseband IQ signal; A display control module, whose input end is connected to the interference perception module, and whose output end is connected to the RF switch module, the frequency hopping receiving module, the interference cancellation module and the frequency hopping transmitting module, is used to output a first control instruction, a second control instruction, a third control instruction and a fourth control instruction based on the interference perception indication signal and the frequency word information of the frequency hopping radio station, which are used to control the RF switch state, the frequency hopping receiving local oscillator, the interference cancellation algorithm parameters and the frequency hopping transmitting local oscillator respectively; A frequency hopping transmission module, whose output end is connected to the RF switch module, is used to up-convert the residual signal based on the fourth control instruction and then output the cancellation playback RF signal to transmit to the RF switch module; The frequency hopping receiving module includes: a limiter, a frequency hopping filter component, a first mixer, a first low-pass filter, a fixed frequency filter down-conversion component, an ADC and a local oscillator generation module; The limiter, the frequency hopping filter component, the first mixer, the first low-pass filter, the fixed-frequency filter down-conversion component and the ADC are connected in sequence; The output end of the local oscillator generation module is connected to the first mixer, the fixed frequency filter down-conversion component and the frequency hopping transmission module; the output end of the ADC is connected to the interference cancellation module and the interference perception module; The limiter is used to limit the initial RF signal transmitted by the receiving antenna and the sampling antenna module, and output the corresponding RF signal z ( t ); The frequency hopping filter component is used to filter the radio frequency signal based on the second control instruction. z ( t ) to adaptively filter out the out-of-band interference of the frequency hopping signal, and output the RF signal after frequency hopping filtering u ( t ); The first mixer is used to filter the RF signal output after frequency hopping. u ( t ) is mixed with N-way frequency hopping local oscillator signals to output the RF signal after frequency hopping g ( t ); The first low-pass filter is used to filter out the RF signal after frequency hopping g ( t ) The high-order components generated by mixing, output low-pass filtered signal v ( t ); The fixed frequency filter down-conversion component is used to convert the low-pass filtered signal based on the N-way fixed frequency local oscillator signal. v ( t ) to filter out-of-band interference and output the baseband analog signal after fixed-frequency filtering and down-conversion b ( t ); ADC is used to convert baseband analog signals b ( t ) performs analog-to-digital conversion and outputs baseband IQ signals; The local oscillator generation module is used to generate one frequency hopping local oscillator signal and N frequency hopping local oscillator signals, as well as one fixed frequency local oscillator signal and N fixed frequency local oscillator signals; The frequency hopping filter assembly includes a low-loss tuning filter, a first three-phase electronic switch, a first low-noise amplifier unit, a high-loss tuning filter, a second three-phase electronic switch, an attenuator, and a second low-noise amplifier unit; The output end of the low-loss tuned filter is connected to the input end of the first three-phase electronic switch; one output end of the first three-phase electronic switch is connected to the input end of the first low-noise amplifier unit, and the other output end is connected to the output end of the first low-noise amplifier unit; the output end of the first low-noise amplifier unit is connected to the input end of the high-loss tuned filter; the output end of the high-loss tuned filter is connected to the input end of the second three-phase electronic switch, one output end of the second three-phase electronic switch is connected to the attenuator, and the other output end is connected to the second low-noise amplifier unit; The low loss tuned filter is used to adjust the corresponding RF signal after limiting. z ( t ) to suppress out-of-band interference and output low-loss tuned filter signal z 1 ( t ); The first three-phase electronic switch is used to select the low-loss tuned filter signal z 1 ( t ) output path is a direct or amplified channel, outputting a low-loss tuned filtered signal z 1 ( t ); The first low noise amplifier unit is used for low loss tuning and filtering the signal z 1 ( t ) to perform low noise amplification processing and output the signal after low noise amplification z 2 ( t ); High loss tuned filter is used for low noise amplified signal z 2 ( t ) or low loss tuned filter signal z 1 ( t ) to suppress out-of-band interference and output the signal after high loss tuning and filtering z 3 ( t ); The second three-phase electronic switch is used to select the signal after high loss tuning and filtering z 3 ( t The output path of the amplifier is the attenuation or amplification channel, which outputs the signal after high loss tuning and filtering. z 3 ( t ); The attenuator is used to tune the filtered signal with high loss. z 3 ( t ) to perform attenuation processing and output RF signal u ( t ); The second low noise amplifier unit is used to tune and filter the signal after high loss z 3 ( t ) performs low noise amplification processing and outputs RF signal u ( t ).

2. The ultra-short wave frequency hopping radio station interference cancellation device according to claim 1, characterized in that: The radio frequency switch module includes a first mechanical switch, a second mechanical switch, a first three-phase electronic switch, a second three-phase electronic switch and N-1 two-phase electronic switches; The input end of the first mechanical switch is connected to the output end of the second mechanical switch and the output end of the first three-phase electronic switch, and is used to output the radio frequency signal of the receiving antenna transmitted by the second mechanical switch to the frequency hopping radio station, or to transmit the cancellation and playback radio frequency signal output by the first three-phase electronic switch to the frequency hopping radio station; The other output end of the second mechanical switch is connected to the input end of the second three-phase electronic switch. One output end of the second three-phase electronic switch is connected to the input end of the first three-phase electronic switch, and the other output end of the second three-phase electronic switch is connected to the frequency hopping receiving module. The second mechanical switch is used to transmit the radio frequency signal from the receiving antenna to the first mechanical switch, or to transmit the radio frequency signal from the receiving antenna to the frequency hopping receiving module via the second three-phase electronic switch. The second three-phase electronic switch is used to transmit the cancellation and playback radio frequency signal to the first three-phase electronic switch. N-1 two-phase electronic switches are used to receive multi-channel radio frequency signals transmitted by the sampling antenna; where N is the number of channels.

3. The ultra-short wave frequency hopping radio station interference cancellation device according to claim 1 or 2, characterized in that: The local oscillator generation module includes a high-stable crystal oscillator, a frequency divider, four phase-locked loops, four low-noise amplifier units, four low-pass filters and two splitters; A highly stable crystal oscillator is used to generate a local oscillator signal; a frequency divider is used to divide the local oscillator signal into local oscillator signals of different frequencies; a phase-locked loop is used to stabilize the local oscillator signal and optimize its quality; a low-noise amplifier unit is used to perform branch amplitude compensation on the stable local oscillator signal and output the local oscillator signal after low-noise amplification; a low-pass filter is used to perform low-pass filtering on the signal after low-noise amplification; and a splitter is used to divide the low-pass filtered local oscillator signal into multiple local oscillator signals. One path of the high-stability crystal oscillator is sequentially connected to the first phase-locked loop, the eleventh low-noise amplifier unit, the eleventh low-pass filter and the first splitter, and outputs N paths of fixed-frequency local oscillator signals; The second path of the high-stability crystal oscillator is connected to the second phase-locked loop, the twenty-first low-noise amplifier unit and the twenty-first low-pass filter in sequence, and outputs a fixed-frequency local oscillator signal; The three channels of the high-stable crystal oscillator are connected to a frequency divider, the other input end of the frequency divider is connected to a frequency-hopping radio, and its output end is connected to a third phase-locked loop and a fourth phase-locked loop; the third phase-locked loop is connected to a thirty-first low-noise amplifier unit, a thirty-first low-pass filter and a second divider in sequence, and outputs N frequency-hopping local oscillator signals; the fourth phase-locked loop is connected to a forty-first low-noise amplifier unit and a forty-first low-pass filter in sequence, and outputs one frequency-hopping local oscillator signal.

4. The ultra-short wave frequency hopping radio station interference cancellation device according to claim 1, characterized in that: The interference cancellation module includes: (N-1)×(K-1) delay units, (N-1)×K weight combining units, two accumulation units and weight control unit; The delay unit is used to perform unit delay on the baseband IQ signal and use pipeline technology to determine the timing matching; the weight combining unit is used to adjust the amplitude and phase of the baseband IQ signal based on the weight signal transmitted by the weight control unit; the accumulation unit is used to perform superposition calculation on the received signal; the weight control unit is used to output each weight signal based on the residual signal; The output end of the first accumulator is connected to the frequency hopping transmission module and the weight control unit, and is used to receive the first digital signal in the baseband IQ signal; the first weight combining unit and the first delay unit input the second digital signal in the baseband IQ signal; an input end of the first weight combining unit is connected to the weight control unit, and an output end thereof is connected to the second accumulator; the output end of the first delay unit is connected to the second delay unit and the second weight combining unit; and so on, the input end of the Kth weight combining unit is connected to the K-1th delay unit and the weight control unit, and the output end is connected to the second accumulator; Similarly, the (N-1)×(K-1)+1th weight combining unit and the (N-2)×(K-1)+1th delay unit input the Nth digital signal in the baseband IQ signal; the other input end of the (N-1)×(K-1)+1th weight combining unit is connected to the weight control unit, and the output end is connected to the second accumulator unit; the output end of the (N-2)×(K-1)+1th delay unit is connected to the (N-2)×(K-1)+2th delay unit and the (N-1)×(K-1)+2th weight combining unit; similarly, the input end of the (N-1)×K weight combining unit is the (N-1)×(K-1)th delay unit and the weight control unit, and the output end is connected to the second accumulator unit; Where K is the number of time domain filter taps.

5. A method for canceling frequency hopping radio interference based on the ultra-short wave frequency hopping radio interference cancellation device according to claim 1, characterized in that: The following steps are involved: Step 1: Based on the first control instruction, the switch is switched to select whether to transmit the RF signal from the receiving antenna to the frequency hopping radio, thereby terminating the current execution; or the initial RF signal is transmitted to the frequency hopping receiving module, thereby proceeding to step 2; wherein the first control instruction is used to control the RF switch state; the initial RF signal includes the multi-channel RF signal output by the sampling antenna module and the RF signal output by the receiving antenna; Step 2: Based on the second control instruction, perform out-of-band filtering and down-conversion processing on the initial RF signal to obtain a baseband IQ signal; wherein the second control instruction is used to control the acquisition of the frequency hopping receiving local oscillator; Step 3: Based on the third control instruction, perform interference signal suppression on the baseband IQ signal and output a residual signal after interference cancellation processing; wherein the third control instruction is used to control the parameters of the interference cancellation algorithm; Step 4: Output an interference perception indication signal based on the baseband IQ signal, and obtain a first control instruction, a second control instruction, a third control instruction, and a fourth control instruction in combination with the frequency word signal of the frequency hopping radio; Step 5: Based on the fourth control instruction, up-convert the residual signal and output the cancellation playback RF signal to transmit to the RF switch module; wherein the fourth control instruction is used to control the acquisition of the frequency hopping transmission local oscillator; Step 6: Transmit the cancellation playback RF signal to the frequency hopping radio through the RF switch module.

6. The method for canceling interference of ultra-short wave frequency hopping radio stations according to claim 5, characterized in that: Step 2 specifically includes the following steps: Step 2.1: Limit the initial RF signal transmitted by the receiving antenna and sampling antenna module, and output the corresponding RF signal z ( t ); Step 2.2: Based on the second control instruction, the RF signal z ( t ) to adaptively filter out the out-of-band interference of the frequency hopping signal, and output the RF signal after the frequency hopping filter u ( t ); Step 2.3: Output the RF signal after frequency hopping filtering u ( t ) is mixed with N-way frequency hopping local oscillator signals to output the RF signal after frequency hopping g ( t ); Step 2.4: Filter out the RF signal after frequency hopping g ( t ) due to the high-order components generated by mixing, output low-pass filtered signal v ( t ); Step 2.5: Based on the N-way fixed-frequency local oscillator signal, the low-pass filtered signal v ( t ) to filter out-of-band interference and output the baseband analog signal after fixed-frequency filtering and down-conversion b ( t ); Step 2.6: Convert the baseband analog signal b ( t ) performs analog-to-digital conversion and outputs baseband IQ signals.

7. The method for canceling interference of an ultra-short wave frequency hopping radio station according to claim 5 or 6, characterized in that: The method for obtaining a residual signal by interference cancellation in step 3 includes the following steps: Step 3.1: Initialize the weights and establish an interference cancellation model based on pipeline technology; Step 3.2: Calculate and update the weights based on the minimum mean square error (MMSE) criterion. Step 3.3: Accumulate and calculate the interference extraction signal based on the updated weights; Step 3.4: Subtract the interference extraction signal from the RF signal transmitted by the receiving antenna to obtain a residual signal after interference cancellation processing.

8. The method for canceling interference of ultra-short wave frequency hopping radio stations according to claim 5, characterized in that: The method for obtaining the interference perception indication signal in step 4 is: Step 4.1: Based on the working mechanism of the frequency-hopping radio, the baseband IQ signal stream is segmented, and each segment corresponds to the interference state at the current moment; Step 4.2: Extract typical features of the intercepted data to alleviate data stream accumulation; the typical features include time domain information and frequency domain information; Step 4.3: Based on the kernel mapping network parameters and boundary parameters, project the representative eigenvalues ​​to the kernel mapping network; Step 4.4: Calculate the decision value of the current data segment in the core mapping network space, compare it with the offline learned decision threshold, determine whether interference exists, and obtain the interference perception indication signal.

9. The method for canceling interference of ultra-short wave frequency hopping radio stations according to claim 5, characterized in that: The parameter optimization method of the sampling antenna module includes the following steps: Obtain the operating frequency band and number of sampling antennas based on the interference scenario of the frequency hopping radio station; The blind zone cancellation model is established by taking the different interference directions and working frequency bands that cannot pass after cancellation as the cancellation blind zone; Based on the minimum blind spot model, determine the distance between the receiving antenna and the sampling antenna, as well as the gain of the sampling antenna.

10. The method for canceling interference of ultra-short wave frequency hopping radio stations according to claim 5 or 9, characterized in that: Step 1 is as follows: Analyze the transmission and reception status of the frequency hopping radio. When the frequency hopping radio is in the transmitting state, the switch of the RF switch module is switched to enable direct communication between the frequency hopping radio and the receiving antenna. When the frequency hopping radio is in the receiving state, the switch of the RF switch module is switched to the cancellation state so that the frequency hopping receiving module can receive the initial RF signal and down-convert it into a baseband signal.

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