Novel joint estimation method of underwater multi-target bearings, frequencies, and time-delays

A new 3-dimensional joint estimation method is presented. With a single echo wave, bearings, frequencies, and time-delays of multiple reflectors are estimated jointly. We construct 2 sub-arrays like ESPRIT, and then make a generalized eigen-decomposition on their auto-correlation matrix and cross-correlation matrix. Bearing parameters can be estimated from eigenvalues, while frequency parameters can be obtained from corresponding eigenvectors. Having modified the time-delay vectors of enveloping with estimated frequencies, we can get the time-delay parameters simultaneously. Computer simulations show that the proposed method can carry out the 3-dimensional joint estimation without additional pairing algorithm in the case of lower SNR. Preferable results are also obtained in water tank experiments, indicating the method is robust for sensor array errors, and showing good potential in applications.