Spectrally compatible aperiodic sequence set design with low cross- and auto-correlation PSL

It is known that unimodular sequence set with low cross- and auto-correlation peak sidelobe level (C/A-PSL) can improve the detection ability of the signal-of-interest in the presence of multipath propagation and/or clutters, while that with specified spectral power null/notch in certain frequency bands can prevent mutual interference of the systems that are operating in the same frequency bands. However, it is exceedingly difficult to design such a unimodular sequence set because nonsmooth quadratic objective function as well as nonlinear unimodular and spectral constraints are involved. In this paper, under the unimodular and spectral constraints, we formulate the sequence set design problem based on minimum C/A-PSL. Then, we apply block successive upper-bound minimization to solve the corresponding NP-hard problem and use the relation of the sequence auto-correlation and its fast Fourier transform (FFT) and inverse FFT to devise an efficient algorithm. Numerical examples show that the proposed method can effectively produce spectrally constrained sequence set with low C/A-PSL.