Stability testing of two dimensional NSHP filters using simplified mapping methods

Stability testing of Non symmetric half plane (NSHP) two dimensional (2-D) recursive digital filters can be carried out using either algebraic or mapping methods. The mapping methods, in general need infinitely large number of steps to determine the stability of given recursive digital filters. Out of the mapping methods, Jury´s row and column algorithms have been considered as highly efficient, even though they still run short of accuracy due to the undefined length of the FFT used. The best mapping method is not yet available and even now, researchers have been working on this problem. In this paper, a mapping method based on row and column concatenation method is being proposed which is made conceptually simple, easy and fast. An optimum value of L is decided to find the stability of the given filters. In this way, the main drawback of the mapping methods, namely the infinitely large number of steps involved in it is reduced to a great extent. Index TermsStability, Mapping methods, Quarter Plane filters (QP),Non-symmetric half plane filters(NSHP).