Fast affine projection adaptation algorithms featuring stable symmetric positive-definite linear system solvers

This paper proposes two patent-pending stable approaches to solve a symmetric positive-definite linear system associated with the fast affine projection (FAP) adaptation algorithm. The first approach can provide an exact solution at a relatively high complexity. The second, based on a novel reciprocating recursion algorithm, gives a reasonable approximate solution at a very low complexity. Simulations show that FAP algorithms incorporating these approaches are stable and well-performing, and therefore are practical.