Convergence properties of the frequency domain block-LMS Volterra adaptive filter

Summary form only given, as follows. This paper investigates the convergence properties of the constrained frequency-domain block LMS (CFBLMS) algorithm and the unconstrained frequency-domain block LMS (UFBLMS) algorithm when applied to truncated Volterra systems. As shown by previous work, the range of stability for the UFBLMS algorithm for linear systems is 1/2 of that with the CFBLMS algorithm. This work verifies that this relationship between the UFBLMS algorithm and the CFBLMS algorithm is valid for truncated Volterra systems as well. This paper further shows through simulation results that the performance of the UFBLMS algorithm is comparable to the CFBLMS algorithm if the step size is adaptive.