A complex electromagnetic environment simulation method based on digital domain synthesis and channel multiplexing

Abstract

The complex electromagnetic environment simulation method based on digital domain synthesis and channel multiplexing includes the following aspects: a co-platform multi-radiation source signal digital domain synthesis generation technology, an antenna array multi-radiation source synthesis signal feed control technology, and a co-platform multi-radiation source synthesis signal generation channel and independent platform radiation source signal generation channel multiplexing technology; under the premise that the number of simulation system channels remains unchanged, the number of signal pulses simulated by the system is significantly increased, the radiation source pulse loss rate is reduced, the complexity of the electromagnetic environment is improved, and the quality of the test results is improved; the technical advantages of the traditional technical scheme are combined; when there is no situation of multiple radiation sources on the same platform, the complex electromagnetic environment can be constructed through pulse sequencing and channel multiplexing in accordance with the implementation idea of the traditional radio frequency simulation system; under the premise that the complex electromagnetic environment simulation requirement remains unchanged, the number of simulation system channels required can be reduced, the hardware scale and technical complexity of the simulation system are reduced, the development cost of the simulation system is reduced, and the test efficiency-cost ratio is improved.

Description

Technical Field

[0001] This invention belongs to the field of electronic information technology, and mainly relates to a method for simulating complex electromagnetic environments based on digital domain synthesis and channel multiplexing. Background Technology

[0002] The ability to adapt to complex electromagnetic environments is one of the important performance requirements for radar countermeasures and reconnaissance equipment, and it is also a key test item in equipment performance testing. Testing requires providing a dynamic, high-density complex electromagnetic signal environment.

[0003] The simulation method is used to test the adaptability of radar countermeasure and reconnaissance equipment to complex electromagnetic environments. This requires the radio frequency (RF) simulation system to realistically simulate various radiation source signals in actual space, constructing a comprehensive, dynamic, and high-density complex electromagnetic signal environment. The RF simulation system typically consists of a microwave anechoic chamber, a signal simulator, and an antenna array. The microwave anechoic chamber provides a space for free propagation of electromagnetic waves, the signal simulator generates various radar radiation source signals, and the antenna array radiates the radar radiation source signals generated by the signal simulator into the microwave anechoic chamber, thus constructing a complex electromagnetic signal environment within the anechoic chamber that varies across multiple domains, including time, space, frequency, energy, and polarization.

[0004] Traditional approaches to constructing complex electromagnetic environments for radio frequency (RF) simulations mainly fall into two categories: one is to use a multi-channel signal simulator combined with a multi-channel antenna array. Each channel of the signal simulator and antenna array simulates a fixed radiation source signal. Increasing the number of channels increases the complexity of the environmental simulation. However, since the signal simulator and antenna array channels consist of a large number of expensive RF components, adding more channels leads to a large system size, high cost, and limited application. The other approach is to queue all signals in chronological order. Signals that exceed the number of system channels and overlap in time are selected according to a certain priority rule, achieving dynamic allocation of signals among channels, improving the signal pulse output rate, and enhancing the ability to simulate complex environments. However, this approach still relies on the number of channels. Insufficient channels can lead to a high signal loss rate, affecting the sorting and identification by the radar under test and the reconnaissance equipment, resulting in unreasonable test results.

[0005] In real-world environments, radar countermeasures and reconnaissance equipment face numerous radiation sources and diverse platform types. Furthermore, a single platform can carry multiple radiation sources with different functions, purposes, or signal patterns. Therefore, during simulation testing, a pressing issue arises: how can the radio frequency simulation system utilize limited hardware resources to simultaneously simulate the signals of multiple radiation sources in space? Summary of the Invention

[0006] To overcome the above-mentioned shortcomings, this invention provides a method for simulating complex electromagnetic environments based on digital domain synthesis and channel multiplexing.

[0007] The technical solution adopted by this invention to solve its technical problem is as follows:

[0008] A method for simulating complex electromagnetic environments based on digital domain synthesis and channel multiplexing includes the following steps:

[0009] 1) Based on the test scenario, radiation sources are divided into two categories: one is multiple radiation sources mounted on the same platform, called common platform radiation sources; the other is radiation sources on other independent platforms, called independent platform radiation sources.

[0010] 2) For a common platform radiation source, a channel of the signal simulator is selected as a dedicated channel. The signals of each radiation source are sorted according to the order in which they arrive at the radar under test for countermeasures and reconnaissance. The pulse signal sequence is obtained. The signal simulator generates the baseband digital signal sequence of each radiation source signal. The center frequency corresponding to one of the radiation source signals is selected as the reference frequency. Based on the arrival time difference, center frequency difference, amplitude and phase difference required for signal polarization simulation, and amplitude and phase difference of the antenna array feed channel caused by the difference in signal center frequency, the baseband digital signals are time-delayed, amplitude and phase modulated. Then, the baseband digital signals are digitally synthesized to obtain the baseband digital synthesized signal.

[0011] 3) The baseband digital synthesized signal in step 2) is converted into an RF synthesized signal by D / A and up-conversion, and then sent to the corresponding feed channel of the antenna array. The antenna array feed channel radiates the signal into the microwave anechoic chamber after completing the unified amplitude control and coarse position control of the signal based on the radiation source signal corresponding to the reference frequency, simulating the power density and spatial angle position of each radiation source signal reaching the radar countermeasure reconnaissance equipment under test.

[0012] 4) For independent platform radiation sources, after sorting the signals according to their arrival time, pulse selection is performed based on the remaining number of channels and the predetermined priority criteria. The dynamic allocation of each signal among the channels is achieved through channel multiplexing. The signal is generated by the signal simulator and output through the corresponding channel. After the antenna array completes coarse position control, fine position control, amplitude and polarization simulation control, it is radiated into the microwave anechoic chamber.

[0013] 5) When the shared platform radiation source situation disappears, the corresponding signal simulator channel and antenna array RF feed channel automatically switch to independent platform radiation source simulation mode, and its function is the same as the channel function described in step 4) above.

[0014] The present invention provides a method for simulating complex electromagnetic environments based on digital domain synthesis and channel multiplexing, which has the following advantages:

[0015] First, under the premise that the number of channels in the simulation system remains unchanged, the number of simulated signal pulses in the system can be significantly increased, the pulse loss rate of radiation sources can be reduced, the complexity of the electromagnetic environment can be increased, and the quality of test results can be improved.

[0016] Secondly, it combines the technical advantages of traditional solutions. When there is no situation where multiple radiation sources are mounted on the same platform, a complex electromagnetic environment can be constructed by pulse sequencing and channel multiplexing, following the traditional radio frequency simulation system implementation approach.

[0017] Third, under the premise that the requirements for simulating complex electromagnetic environments remain unchanged, the number of channels required for the simulation system can be reduced, the hardware scale and technical complexity of the simulation system can be reduced, the development cost of the simulation system can be reduced, and the cost-effectiveness of testing can be improved. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0019] A method for simulating complex electromagnetic environments based on digital domain synthesis and channel multiplexing includes the following steps:

[0020] 1) Based on the test scenario, radiation sources are divided into two categories: one is multiple radiation sources mounted on the same platform (vehicle, aircraft or ship), called common platform radiation sources; the other is radiation sources on other independent platforms, called independent platform radiation sources.

[0021] 2) For a common platform radiation source, a channel of the signal simulator is selected as a dedicated channel. The signals of each radiation source are sorted according to the order in which they arrive at the radar under test for countermeasures and reconnaissance. The pulse signal sequence is obtained. The signal simulator generates the baseband digital signal sequence of each radiation source signal. The center frequency corresponding to one of the radiation source signals is selected as the reference frequency. Based on the arrival time difference, center frequency difference, amplitude and phase difference required for signal polarization simulation, and amplitude and phase difference of the antenna array feed channel caused by the difference in signal center frequency, the baseband digital signals are time-delayed, amplitude and phase modulated. Then, the baseband digital signals are digitally synthesized to obtain the baseband digital synthesized signal.

[0022] 3) The baseband digital synthesized signal in step 2) is converted into an RF synthesized signal by D / A and up-conversion, and then sent to the corresponding feed channel of the antenna array. The antenna array feed channel radiates the signal into the microwave anechoic chamber after completing the unified amplitude control and coarse position control of the signal based on the radiation source signal corresponding to the reference frequency, simulating the power density and spatial angle position of each radiation source signal reaching the radar countermeasure reconnaissance equipment under test.

[0023] 4) For independent platform radiation sources, after sorting the signals according to their arrival time, pulse selection is performed based on the remaining number of channels and the predetermined priority criteria. The dynamic allocation of each signal among the channels is achieved through channel multiplexing. The signal is generated by the signal simulator and output through the corresponding channel. After the antenna array completes coarse position control, fine position control, amplitude and polarization simulation control, it is radiated into the microwave anechoic chamber.

[0024] 5) When the shared platform radiation source situation disappears, the corresponding signal simulator channel and antenna array RF feed channel automatically switch to independent platform radiation source simulation mode, and its function is the same as the channel function described in step 4) above.

[0025] This invention includes a shared-platform multi-radiation-source signal digital domain synthesis generation technology, an antenna array multi-radiation-source synthesis signal feed control technology, and a shared-platform multi-radiation-source synthesis signal generation channel and an independent platform radiation-source signal generation channel multiplexing technology. It features advanced concepts, economical solutions, strong versatility, and good applicability. Under the premise of unchanged channel count in the simulation system, it can significantly increase the number of simulated signal pulses, reduce the radiation-source pulse loss rate, improve electromagnetic environment complexity, and enhance the quality of test results. It also incorporates the advantages of traditional technologies. When there are no multiple radiation sources on the same platform, complex electromagnetic environments can be constructed using pulse sequencing and channel multiplexing, following the traditional RF simulation system implementation approach. Under the premise of unchanged complex electromagnetic environment simulation requirements, it can reduce the number of channels required in the simulation system, reduce the hardware scale and technical complexity of the simulation system, lower the development cost of the simulation system, and improve the cost-effectiveness of testing.

[0026] The parts not detailed above are existing technologies and therefore have not been described in detail.

Claims

1. A method for simulating complex electromagnetic environments based on digital domain synthesis and channel multiplexing, characterized in that: Includes the following steps: (1) According to the test scenario, the radiation sources are divided into two categories: one is multiple radiation sources mounted on the same platform, which are called common platform radiation sources; the other is radiation sources on other independent platforms, which are called independent platform radiation sources. (2) For a common platform radiation source, a certain channel of the signal simulator is selected as a dedicated channel. The signals of each radiation source are sorted according to the order of arrival time of the radar countermeasure reconnaissance equipment under test to obtain a pulse signal sequence. The signal simulator generates the baseband digital signal sequence of each radiation source signal respectively. The center frequency corresponding to one of the radiation source signals is selected as the reference frequency. Based on the arrival time difference, center frequency difference, amplitude and phase difference required for signal polarization simulation, and the amplitude and phase difference of the antenna array feed channel caused by the difference in signal center frequency, the baseband digital signals are delayed, amplitude and phase modulated. Then, the baseband digital signals are digitally synthesized to obtain the baseband digital synthesized signal. (3) The baseband digital synthesis signal in step (2) is converted into a radio frequency synthesis signal by D / A and up-conversion, and then sent to the corresponding feed channel of the antenna array. The antenna array feed channel is based on the radiation source signal corresponding to the reference frequency, and after completing the unified amplitude control and coarse position control of the signal, it radiates to the microwave anechoic chamber to simulate the power density and spatial angle position of each radiation source signal reaching the radar countermeasure reconnaissance equipment under test. (4) For independent platform radiation sources, after sorting according to the arrival time of each radiation source signal, pulse selection is performed according to the remaining number of channels and the predetermined priority criteria. The dynamic allocation of each signal between channels is achieved through channel multiplexing. The signal is generated by the signal simulator and output through the corresponding channel. After the antenna array completes coarse position control, fine position control, amplitude and polarization simulation control, it is radiated into the microwave anechoic chamber. (5) When the common platform radiation source situation disappears, the corresponding signal simulator channel and antenna array RF feed channel automatically switch to independent platform radiation source simulation mode, and its function is the same as the channel function described in step (4) above.