A Multi-channel Time-Frequency Accumulation Processing Method for Instantaneous Broadband Multi-frequency Composite Radar Signal

Abstract

The invention discloses a multi-channel time-frequency accumulation processing method for instantaneous broadband multi-frequency composite radar signals, which includes: target scattered echoes are sent to a band-pass filter group to filter out each of the transmitted multi-frequency signals after passing through a low-noise radio frequency receiving link Carrier modulation spectrum; each carrier modulation spectrum is down-converted to the baseband with the corresponding carrier signal, and the pulse pressure processing is performed through a module matching the constant envelope modulation signal; each frequency channel is sent to the Doppler correction processing module after pulse pressure, Solve the problem of echo crossing Doppler units on different carrier frequency channels; the corrected channel signals are sent to the logic selection synthesis module to identify the interference of each frequency channel, select the undisturbed channel, and use non-coherent synthesis The method completes the accumulation of echo energy on the range-Doppler two-dimensional map. The invention can solve the Doppler frequency shift and the corresponding inter-unit problem, and improve the anti-jamming and anti-interception performance of the radar.

Description

technical field [0001] The invention belongs to the technical field of radar signal processing, and relates to wideband signal demodulation, wideband signal filtering, pulse pressure, Doppler frequency shift correction, cross-range unit correction and synthesis accumulation, and is used for radar electronic warfare and anti-jamming. Background technique [0002] With the development of modern military science and technology, especially with the progress of related disciplines such as microelectronics technology and signal information processing technology, radar-related electronic interference and anti-jamming have become one of the focuses of future battlefield competition, causing radar's The application environment is deteriorating day by day, and it is very vulnerable to the reconnaissance of enemy reconnaissance equipment and the subsequent interference, or even direct attack. Based on the current situation of complex environment in all aspects of the battlefield, the c...

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Problems solved by technology

[0004] However, many theoretical foundations of wideband radar are not yet fully mature, and many key technologies, such as the reduction in the number of accumulated pulses caused by the movement of cross-distance units within the coherent processing interval (Coherent Processing Interval: CPI) that exists in wideband detection, are still in the theoretical research process. Among them; in addition, the broadband signal is restricted by hardware resources such as ultra-high-speed AD sampling, large-capacity data transmission network and high-speed digital signal processor in engineering implementation, and some conventional methods are difficult to implement on the actual hardware platform

As far as the current state is concerned, conventional radars still use narrowband (several megahertz) signals, but the modulation form of linear frequency modulation is too simple to be used as an effective anti-intercept signal

In addition, instantaneous broadband can also be achieved through simultaneous multi-frequency, but the Doppler frequency shift of moving targets and the corresponding cross-unit problems that may be generated by simultaneous multi-frequency will seriously affect the detection of targets. At present, this aspect, especially for engineering applications There is no relevant report on the practical and practical solution

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