High-Resolution Dip Estimation Using Plane-Wave Annihilator Filters

A new parametric method for phase velocity estimation with an array of sensor is presented. It does not need a preliminary group velocity calculation and it estimates the function as a whole, providing a continuous and analytic expression. The novelty of the method stands in the velocity model and the initialization of the estimation. The model is based on a spline. This makes the functions smooth enough to guarantee the method's robustness to noise and undesired waves. The search of the best velocity function is initialized with a rough estimate provided by a frequency-wavenumber transform of the data, which highly helps the convergence. This method has been applied to synthetic and real surface wave signals. In both cases the signals corrected with the estimated velocity have a good alignment, in nearly all the spectrum of the wave.