Mimicking Ship-Radiated Noise With Chaos Signal for Covert Underwater Acoustic Communication

Shuhua Huang,Yuewei Dai,Guangjie Liu,Xiaogeng Hou,Wen Tian,Weiwei Liu

doi:10.1109/access.2020.3027022

Abstract

With the increasingly fierce competition for marine resources, underwater acoustic communication as the main form of underwater communication, its security has received more and more attention. The traditional underwater acoustic communication technology with fixed frequency and modulation may cause information leakage and location exposure of the communicating platform. The communication based on ocean noise is helpful to improve the communication security. This article proposes a new covert underwater acoustic communication scheme based on ship-radiated noise and chaos signal. Firstly, the characteristics of chaos signal is studied, which is generated by the Chebyshev sequence, and the reconstruction process of ship-radiated noise is analyzed. Secondly, we generate mimic ship-radiated noise containing the secret message based on the time and frequency feature of the chaos signal and ship-radiated noise. Finally, resampling technology is used to equalize the Doppler frequency shift, and time inversion mirror technology is used to perform multipath channel equalization. Simulation and sea experiment verify the effectiveness and feasibility of this scheme. In the sea experiments, the proposed scheme can reliably transimit over 40 per second when the communication distance is about 10km.

Highlights

With the exploitation and utilization of marine resources, such as marine environmental monitoring, natural disaster warning [1], [2], higher requirements are put forward for underwater transmission of information
COVERT UNDERWATER ACOUSTIC COMMUNICATION we briefly describe several proposed covert underwater acoustic communication schemes based on acoustic camouflage and chaos signal
PROPOSED METHOD Based on the correlation characteristics of the chaos signal, this article proposes the covert underwater acoustic communication scheme based on mimic ship-radiated noise(CUACS)

Summary

Introduction

With the exploitation and utilization of marine resources, such as marine environmental monitoring, natural disaster warning [1], [2], higher requirements are put forward for underwater transmission of information. As one of the important methods, underwater acoustic communication (UAC) has attracted extensive research in recent years. The covert underwater acoustic communication (CUAC) can ensure the secure transmission of the secret message and. The traditional CUAC mainly realizes the concealment of underwater acoustic communication from two aspects. The first method is to conceal communication signal by making the enemy unable to receive the communication signal. At present, this kind of CUAC method is realized through transmission control and signal modulation.It can form the transmitting signal with certain directivity by using appropriate transducer structure, array design and occlusion technology. It is difficult to obtain the orientation and distance of the communication party in advance, and the transmission module is quite difficult to design. The application of spread spectrum technology is combined with acoustic carrier communication to maintain a low signal to noise ratio (SNR)

Methods

Results

Conclusion