In this paper, we describe a new algebraic structure called V-vector algebr
a, which is a formal basis for the development of Volterra-adaptive filter
algorithms as an extension of linear-adaptive techniques. In this way, fast
and numerically stable adaptive Volterra filtering algorithms can be easil
y derived from the known linear theory. V-vector algebra can also be applie
d to deal with linear multichannel filters with channels of different memor
y lengths, A reformulation of the Lee-Mathews fast recursive least squares
(RLS) algorithm and a nem fast and stable Givens rotation-based square root
RLS algorithm, both derived using V-vector algebra, are finally presented.