Research On Wide Band Chirp Signal Based On DRFM

Linear frequency modulation (LFM or Chirp) signal has the excellent time-frequency resolution, and is easy to obtain much higher pulse compression ratio, and could get large detecte range. It is a usable signal in modern radar. Based on digital radio frequency memory(DRFM), the double linear Chirp transformation is brought up to the linear frequency modulation signal, it will be using a narrow band of DRFM to reconstruct a wide band Chirp signal in some certain conditions. Chirp signal time domain waveform has been simulated and also simulated the signal waveform before and after the double linear Chirp transformation. It has provided some reconstructed signal waveform for unmatched Chirp signal and non-Chirp signal by pass the double linear Chirp transformation simultaneously.DRFM can store the signal to digital memory from certian band width, and could reconstruct the signal output to using. DRFM is a radar jamming technology which generate jamming signal by using the rules of received radar transmite signal and echo modulation, especialy decoy deceived jamming signal. According to the band relationship between the Chirp signal and the DRFM, it could be divided into the two conditions, width band Chirp transformation and narrow band one.Except for the input linear frequency modulation signal, because of the complexbility of electronic warfare signal circurstance, it has considered the input signal for general radiao frequency pulse and phase encode pulse, it has researched the signal reconstruction for those signal pass the double linear Chirp transformation.