Hyper Chaotic Logistic Phase Coded Signal and Its Sidelobe Suppression

A novel hyperchaotic coding scheme and corresponding optimal selection method are proposed to obtain the hyper chaotic logistic phase code (HCLPC) signal, which exhibits great electronic counter-counter measure (ECCM) performance in the presence of digital radio frequency memory (DRFM) repeat jammers and netted radar systems. Similar to the random noise signal, the HCLPC signal has an ideal average ambiguity function and cross ambiguity function. However, the HCLPC signal can overcome the difficulties of reference signal storage and transmitter-receiver isolation for random signals. High range sidelobe would exist for finite length of transmit signal in practice. The Tikhonov regularization constrained total least squares algorithm (TRCTLSA) is first proposed to range sidelobe suppression of the HCLPC signal when data inaccuracy and white Gaussian noise is taken into account, and a global optimal solution to this algorithm is given. Simulation shows that it has a better sidelobe suppression effect than other ways. When Gaussian-noise variance is less than 0.01, the sidelobe level can decrease to the order of -55 dB, but the signal-to-noise ratio (SNR) loss is less than 0.05 dB. As a digital sidelobe suppression filter procedure, it can be widely used in noise reduction environments, image enhancements, and easily ported to sidelobe suppression applications of other signals as well.