Design of orthogonal waveforms based on continuous chaos frequency modulation

摘要

In view of the problem that the orthogonality of MIMO radar waveform decreased with the increase of number of waveforms, using the pseudo-random and initial value sensitivity of continuous chaotic system, this paper presents a design method of orthogonal waveform based on the continuous chaotic frequency modulation. Firstly, the mathematical expression of orthogonal continuous chaos frequency modulation signal (OCCFMS) is given, autocorrelation and quasi-orthogonal property is analyzed, and proposes a progressive chaotic particle swarm optimization algorithm to optimize the chaos initial value. Performance analysis and simulation results show that OCCFMS presents quite good performances in ambiguity function???autocorrelation and pseudoorthogonal property, the performance of the waveform is affected by the chaos initial value. Using the suggested method to optimize the initial value, can get any number of orthogonal waveforms, the precision of optimization is higher, can further reduce the autocorrelation sidelobe peak and cross-correlation peak of OCCFMS, and the autocorrelation sidelobe peak and cross-correlation peak of each orthogonal signal of the waveform set are very close, and can be applied as a kind of promising MIMO radar signals.