Error estimation of pulse pair correlation differential phase estimator of sonar array

Beamforming techniques are the key technique of multibeam bathymetry systems. In this paper, the authors discuss the technique of pulse pair correlation differential phase estimator (PPCDPE) for a sonar array, which is suitable for multibeam bathymetry. In PPCDPE, the noise can be reduced, so the error characteristics are better than that of both techniques widely used at present, i.e., the delay-weight-summing technique and the differential phase estimator (DPE), in the direction other than the near-specular direction. The mean and standard deviation of PPCDPE and their dependence on the parameters of the sonar and the sea bottom are discussed in detail. The figure for the estimation uncertainty of the phase difference is presented and the results are obtained for the simulated data. The standard deviation of σ PPCDPE increases slowly with the decreased grazing angle. It is useful especially for the outer beams. If the authors choose reasonable parameters and S/N, the standard deviation σ may be in the range of (0.3-0.5)%