Using multirate architectures in realizing quadratic Volterra kernels

Multirate architectures have been used for realizing linear FIR digital filters with reduced computational complexity. The Volterra kernel can be represented as a generalized convolution. It would thus be expected that multirate architectures could be used to advantage in realizing Volterra kernels as well. The quadratic Volterra kernel may be realized in the form of an "LDL structure." The LDL structure includes a set of FIR filters of increasing length, which may be realized in a computationally efficient manner using multirate architectures.