Chaotic modulation detection for underwater acoustic communications via instantaneous features

Modulation detection is important for underwater military communications and warfare applications. Chaotic modulations based on chaotic sequences are proposed to protect confidential underwater communications. In this paper, we develop a detection algorithm employing instantaneous phase and frequency for underwater acoustic communications. The key features derived from instantaneous phase and frequency are used to detect two chaotic modulations. They are chaotic M-ary phase shift keying (CMPSK) and chaotic M-ary frequency shift keying (CMFSK), which are designed to provide confidential underwater communications. Simulation and experimental results confirm the effectiveness of our proposed algorithm for chaotic modulation detection.