Three-dimensional positioning based on TOA combining acoustic signal and optical signal

Abstract

 In recent decades, the massive depletion of the earth's terrestrial resources has turned people's attention to the ocean, so many underwater technologies have emerged and developed rapidly with the comprehensive progress of human science. Since the TOA positioning algorithm only needs a synchronous time source, the application of the TOA positioning algorithm by the traditional underwater wireless sensor system network is very common. Underwater positioning technology uses underwater sensor network (UWSN) to locate unknown nodes, which can be divided into underwater acoustic communication positioning and water optical communication positioning according to different transmission channels. The characteristics of underwater acoustic communication and water optical communication determine that the former has better accuracy in long-distance transmission, and the latter has better accuracy in short-range positioning. In this paper, the weight coefficients of sound and light are set separately to obtain the distance cut-off values of sound and light channels. The distance demarcation value can be changed according to the actual environment and needs. We will set the threshold of the impact factor of the underwater environment to ensure that the accuracy error caused by environmental losses is minimized. The reasonable arrangement of UWSN's anchor nodes will maximize energy savings. Simulation results show that the proposed method makes reasonable use of the advantages of acoustic signal and optical signal, and obtains more accurate positioning results after setting the threshold.