A New Method of Multi-Component Source Signal Coding

The usage of system bandwidth is restricted when coding multi-component linear frequency modulation (LFM) source signals that used in multi-beam systems, and the multicomponent echo signal will exist serious time-frequency superposition if the frequency bands of the signal components are overlapped. For solving these problems, a new multi-component LFM source signal coding technique based on fractional Fourier transform (FrFT) is analyzed in this paper. Using the predominant performance of FrFT when processing LFM signals, the theoretical position that LFM signal distributed in the fractional Fourier domain (u domain) and the coding theory of multi-component LFM source signals is proposed, so the utilization ratio of the system band is improved and we can extract or separate the signal components by band-pass filter in the u domain easily. The noise immunity of FrFT is also presented along with the simulation results. The method proposed in this paper provides a new and effective path to code multi-component LFM source signals.