A WEIGHTED LEAST-SQUARES METHOD FOR THE DESIGN OF STABLE 1-D AND 2-D IIR DIGITAL-FILTERS

In this paper, we present a new approach to the least-squares design o f stable infinite impulse response (IIR) digital filters, The design i s accomplished by using an iterative scheme in which the denominator p olynomial obtained from the preceding iteration is treated as a part o f the weighting function, and each iteration is carried out by solving a standard quadratic programming problem that yields a stable rationa l function, When the iteration converges, a stable and truly least-squ ares solution is obtained. The method is then extended to address the least-squares design of stable IIR two-dimensional (2-D) filters, Exam ples are included to illustrate the proposed design techniques.