A method to improve the frequency measurement accuracy of Doppler velocity log

Doppler Velocity Log (DVL) is the mainstream equipment for measuring the velocity of surface or underwater platform. In this paper, the RANSAC (Random Sample Consensus) algorithm is used to estimate the Doppler frequency shift, so that the velocity measurement has higher stability. The main step of DVL's signal processing is to measure the Doppler frequency shift according to the principle that the phase of complex correlation is a liner function of the Doppler frequency shift. Then, the speed of the platform is calculated and the measurement accuracy is improved by using RANSAC algorithm. In order to verify the effectiveness of the method, the simulation is made in which the signal form of CW (Continuous Wave) pulse pairs is used. The results show that the stability using the proposed method is obviously improved.