Design of Orthogonal Polyphase Code Set Based on Multi Pulse Joint Processing

The orthogonality of multiple-input multiple-output (MIMO) radar transmission signals can be improved without changing the operating parameters of the radar through multipulse joint processing. An efficient echo processing algorithm and optimization criteria for a phase-coded set suitable for multi-pulse joint processing are introduced in this paper. The characteristics of both the normalized auto-ambiguity function and the crossambiguity function of the signals are considered in the optimization objective. In order to effectively improve the efficiency of generating phase-coded sets while ensuring signal orthogonality, an accelerated optimization algorithm based on global search combined with local search is proposed in this paper. More specifically, computational complexity is reduced by avoiding a large number of unnecessary calculations during the updating of the ambiguity functions after the code set is perturbed. The orthogonality gain brought by the optimization algorithm proposed in this article, as well as the time advantage of the accelerated optimization algorithm, is verified by simulation results.