A new double filters algorithm for hyperbolic location tracking

A double filters algorithm is presented to solve the instability problem of tracking in 3D 4-station hyperbolic location systems. The conception of ghost target was defined and introduced to the hyperbolic location tracking. The ghost target, especially when close to the true target, would result in two solutions (ambiguity) or non-solution of hyperbolic location, and divergence of filter. Double filters algorithm was constituted by two filters, one for tracking the true target, the other for tracking the ghost target. Simulations are employed to evaluate the performance of the proposed algorithm.