A NEW STABILITY TABLE FOR DISCRETE-TIME-SYSTEMS

In this paper a new sequence of symmetric polynomials {S(i)(z)}i=o(n), associated with the characteristic polynomial of the system D(z), is defined which has a simple relationship to the sequence of polynomials used in the well-developed Marden-Jury test. A new stability table which is very similar to the Routh Table for continuous-time systems is then given to construct this sequence. As compared with the Marden-Jury table, the new table requires only about half the number of elements but can be applied with all the existing results of the previous technique. Numerical examples are given to illustrate the new method with comparisons with other existing techniques.