Under-ice Underwater Acoustic communication based on direct sequence spread spectrum system with parametric emission

With the development of Arctic Underwater Acoustic, the under-ice underwater acoustic communication has gradually become an important indicator. It requires the system has low complex multipath structure and low interference between users to keep the autonomous underwater vehicles (AUV) work stably. This paper presents the technique of under-ice underwater acoustic communication based on parametric transmitter and direct sequence spread spectrum system. The differential signal of parametric array has a narrow directivity similar to the original signal, which can reduce the multipath effect, and improve the reuse rate of underwater acoustic channel at the same time. Spread spectrum underwater acoustic communication technology is capable of communicating under the condition of low signal to noise ratio (SNR), and confidentiality of the pseudo-random sequence can meet the requirements of remote communication. The theoretical research and outfield trial verify the feasibility and effectiveness of the proposed under-ice underwater acoustic communication method.