An effective method to eliminate the bias in focus

In focal underdetermined system solver (FOCUSS), a problem of serious bias in the amplitudes of frequencies is first shown in this paper. And a new method is presented to eliminate the bias effectively. Although a multi-resolution method has already been proposed to achieve greater accuracy than allowed by the grid recently, to eliminate the serious bias in amplitudes it needs much more computation. Therefore a new and simple method is proposed based on a relatively accurate estimation of the locations. The effectiveness of the proposed method is proved by computer simulation.