Steiglitz McBride's method for designing IIR filter
[B,A] = stmcb(H,NB,NA) [B,A] = stmcb(H,NB,NA,N) [B,A] = stmcb(H,NB,NA,N,Ai) [B,A] = STMCB(Y,X,NB,NA,N,Ai)
Impulse response of filter.
Order of the numerator polynomial.
Order of the denominator polynomial.
Number of iterations.
Initial numerator polynomial.
Output sequence.
Input sequence.
Numerator polynomial of order NB+1 of the designed filter.
Denominator polynomial of order NA+1 of the designed filter.
Computes the numerator and denominator polynomials in z-1 of order NB+1 and NA+1 which closely approximate a given impulse response H. The close approximation is done by updating the numerator and denominator polynomial iteratively N times. If N is not specified in the input, the value of N is 5 by default. Also, if the initial numerator polynomial Ai is not specified in the input, it is computed internally using prony function with value NB=0.
If instead of H, the output sequence Y and input sequence X are given, it computes the numerator polynomial B and denominator polynomial A of a system which would give Y when X is passed through it. Note here that the lengths of Y and X must be the same. This function is a clone of MATLAB's function and hence gives similar results.
// any arbitrary impulse response H=[1 2 3 4 5 4 3 2 1]; // numerator and denominator polynomials of order 4 representing h [B,A]=stmcb(H, 4,4) // input sequence X=[1 -1 3 -1 1 0 1 0]; //output sequence Y=[1 1 1 1 1 1 1 1]; // B and A which represent the numerator and denominator polynomial of a system relating Y to X after 15 iterations are given by [B,A]=stmcb(Y,X,4,4,15) |  |  |