Quadrature and inphase FIR filter design for arbitrary delay compensation

A method is presented for generating a pair of filters to separate the inphase and quadrature components of a signal and to compensate for an arbitrary delay. Given a delay, the coefficients of the corresponding pairs of filters are appropriately selected from the coefficients of a common FIR filter. This filter is designed to include the coefficients of filter pairs for a set of delays. For other delays, interpolation is used to obtain the coefficients. It is shown that it is possible to limit interpolation effects to negligible range. Unlike previous approaches, this method has the advantage of requiring the design of only a single filter (the common filter) for all delays