Active sonar performance improving using Costas-P4 hybrid waveform

Abstract

Costas frequency-hopped waveform is a class of pulse compression waveforms with thumbtack ambiguity function. It can provide higher precision on range and speed estimation for a target when used as a transmit waveform in an active sonar system. To improve active sonar performance, Costas-P4 hybrid waveform for active sonar based on Costas frequency modulation and P4 polyphase modulation is proposed in this article. Simulation results show that this design achieves better resolutions and detection performance without increasing the size of the code. Furthermore, Costas-P4 waveform's rangeDoppler coupling is closer to zero than Costas waveform with same frequency codes length. It is also found that Costas-P4 waveform yields similar performance to LFM in a reverberation-limited environment.