Constant envelope multiple trellis-coded MSK for phase coded waveforms in complementary sequences sensor pulse compression

摘要

Complementary coded pulse compression waveforms implementation is introduced in many publications based on using the quadrature phase shift keying modulation (QPSK). The abrupt phase changes in QPSK can lead to fluctuations in the signal waveform amplitude and make it susceptible to system nonlinearities. This can lead to sidelobes non-cancellation because of imbalance correlation in compressing the two coded pulses. This paper proposed complementary sequences pulse compression waveforms based on using multiple trellis-coding with minimum shift keying (MSK) modulation for each sequence. A special design of trellis encoders is proposed to maintain a constant envelope waveform to be robust to nonlinearities and getting a high error rate performance in detecting the complementary sequences in noise effect. Therefore, results explored a perfect zero sidelobe levels in pulse compression.