H. Fan et Xq. Liu, DELTA LEVINSON AND SCHUR-TYPE RLS ALGORITHMS FOR ADAPTIVE SIGNAL-PROCESSING, IEEE transactions on signal processing, 42(7), 1994, pp. 1629-1639
In this paper, we develop delta operator based Levinson and Schur type
on-tine RLS algorithms. Such algorithms have the potential of improve
d numerical behavior for ill-conditioned input data. These new algorit
hms are obtained by a unified transformation on the existing q operato
r based ones. We first show that the conventional lattice structure ca
n be naturally derived when the backward delta operator is used. With
this operator, Levinson and Schur algorithms for the stationary stocha
stic model in q-domain can easily be transformed into the delta domain
. Then, same transformation will be applied to the q-domain on-line Le
vinson and Schur type RLS algorithms to obtain the delta-domain counte
rparts. Their normalized versions as well as a systolic array architec
ture implementing the new delta Schur RLS algorithm are proposed. Exte
nsion to the equal length multichannel case is also given. Computer si
mulations show the expected numerical advantages of the delta-based al
gorithms for fast-sampled data in real time, over the q-domain ones un
der finite precision implementation.