A test of the stability of the twodimensional recursive digital filter
Abstract
An algorithm for testing the stability of a twodimensional recursive digital filter is developed. The method tests a twovariable Hurwitz polynomial by using the theory of positive real functions. The stability conditions of a discrete system and a continuous system connected by a bilinear transformation for two variables are investigated. It is shown that the test of a twovariable Hurwitz polynomial reduces to a test of a Hurwitz polynomial of a lower order with respect to one variable and to a sign test of a real twovariable polynomial. The sign test is performed by Sturm's test extended for twovariables.
 Publication:

Electronics Communications of Japan
 Pub Date:
 July 1985
 Bibcode:
 1985JElCo..68....1M
 Keywords:

 Algorithms;
 Digital Filters;
 Image Processing;
 Recursive Functions;
 Stability Tests;
 Linear Transformations;
 Polynomials;
 Real Variables;
 Electronics and Electrical Engineering