Precise Localization of Autonomous Underwater Vehicles based on Backscattered Acoustic Communication

Autonomous Underwater Vehicles (AUVs) need accurate positioning when performing tasks, however, electromagnetic wave attenuation is serious underwater, which can only realize short-distance high-speed communication, greatly limiting the application scenarios of AUVs. Traditional end-to-end hydroacoustic communication can realize long-distance communication, but it has high power consumption and high maintenance cost, which is not suitable for long-term navigation and positioning of AUVs performing small tasks in local waters. This paper provides a new solution for accurate localization of AUVs when performing small tasks by introducing the underwater backscatter communication technique. The Acoustic Identification Tags made by this technology is deployed on the seabed, which can transmit the accurate position information of the tag to the AUVs within the communication range of the tag. By improving the traditional six-element cross array of the acoustic intensity vector method to a five-element cross array to improve the localization accuracy of the acoustic intensity vector method, and then calculating the position of the AUVs with respect to the tag with this method, high accuracy positioning of the AUVs can be realized. This method is used to calculate the position of the navigator relative to the tag, which can realize the high-precision positioning of the navigator. When calculating the position of the navigator relative to the tag, it is found that the improved array has a better positioning effect, which can meet the high-precision positioning of the underwater navigator within the communication range of the AID Tags.