Study on ultra short baseline positioning system based on improved quad array and extended Kalman filter

Ultra-short baseline equipment has been widely used in underwater positioning because of its small size and flexible use. In order to eliminate the phase ambiguity in the long distance measurement of ultra-short baseline system, an improved four-element array is proposed, which solves the above-mentioned problem effectively and improves the positioning accuracy. At the same time, in order to improve the precision of the phase difference between the measured elements, the acoustic signal is denoised by using the extended Kalman filter. The simulation results show that comparing with the traditional matrix, the improved four-element matrix improves the positioning accuracy by nearly one order of magnitude, and effectively reduces the number of primitives comparing with the improved eight-element matrix.