A LFM-based adaptive wake-up signal detection approach for underwater acoustic communication system

The paper focuses on wake-up mechanism for underwater acoustic communication (UAC) system. Wake-up mechanisms for UAC terminals play an important role in reducing the power consumption and extending the battery life. Compared with terrestrial wireless counterparts, the wake-up receivers for UAC terminals are challenged by the severe underwater acoustic channels, which are characterized by doubly-selective fading and low signal-to-noise ratio (SNR). Furthermore, the wake-up receiver is with weak processing ability. The paper proposes a wake-up mechanism named as channel-adaptive detection and joint decision (ChAD-JD). ChAD-JD uses linear frequency modulation (LFM) as wake-up signals. In order to increase the detection probability and reduce the probability of false alarm, the novel approach applies channel-adaptive detection and joint decision methods, respectively. Simulation and experimental results show that ChAD-JD is more reliable and effective compared with traditional LFM-based detection methods with a fixed threshold.