The relationship between sea-bottom reverberation spatial-temporal correlation function of correlation sonar for velocity measurement with pitch of vessels

As the attitude of the vessel keeps changing, if the attitude is not considered in the theoretical correlation function, it will have a bad influence on the accuracy of the velocity measurement. By considering the changes of the irradiation area of the signal on the bottom of the sea induced by the tilt of the vessel and inducing multi-order Bessel functions into the theoretical correlation function, the improved theoretical correlation function can be obtained.Meanwhile, the results of simulation, which is based on the model of FOM that is chosen based on the parameter of correlation sonar, shows that the improved theoretical correlation function reduces the error of the correlation sonar to less than 1%. Pitch of vessels can influence spatial-temporal correlation function. The theoretical correlation function considering pitch of vessels is closer to the real circumstance,and has good agreement with the correlation coefficients of the simulation results, so it can be used to realize the velocity measurement with higher accuracy.