Research On DRFM Interference Suppression Algorithm

Modern radar is facing increasingly complex electromagnetic environment,along with the development of Digital Radio Frequency Frequency Memory,serious challenges are just around the corner.In view of the LFM pulse compression radar,the interference suppression algorithm based on the technology of DRFM is researched and simulated in this paper.Specific contents as follows:1.This paper introduces the characteristics of LFM pulse compression radar signal and DRFM,builds the mathematical model of LFM signal.Combined with the workings of a jammer the kinds and styles of DRFM interference are illustrated,emphatically the working process of the drawing-out interference from wave door.2.Using the delay characteristics of DRFM interference,a kind of launch waveform based on first-phase modulation is designed.The design train of thought is expounded by deriving formula in this paper.The value of coefficient has an influence on the signal in the FRFT domain,a lot of simulation is done to analyze the impact.The paper also verify the effectiveness of multi-channel matched filtering to estimate the number of the delay of the interference.And it realizes the algorithm against the distance deception jamming as well as the distance-velocity deception jamming.This paper also compares three kinds of algorithms and simply introduces hardware implementation of FRFT.3.Adopting the idea of pulse diversity and using the delay characteristics of interference pulse,design a kind of launch waveform based on quantization coding within the pulse is designed to suppress the interference.During the process of matched filtering after decoding,the amplitude of the interference is mismatched,the energy of interference is inhibited.The algorithm is proved effective through simulation.4.The improvement measures are put forward based on last algorithm.Select a set of relevant minimum of coding instead of random quantization coding.It has been verified by simulation that the new algorithm has improved the performance than before.Following this concept,a kind of launch waveform based on pseudo random coding between pulse amplitude modulation is designed to make up the defects of the last algorithm,such as not easy to operate in the actual situation,then it is simply simulated.