A NEW APPROACH TO THE DESIGN OF CRITICALLY SAMPLED M-CHANNEL UNIFORM-BAND PERFECT-RECONSTRUCTION LINEAR-PHASE FIR FILTER BANKS

A new approach is presented for the design of uniform-band M-channel p erfect-reconstruction (PR) FIR filter banks employing linear-phase ana lysis and synthesis filters. The technique designs on the impulse resp onses of the analysis filters directly. The design problem is formulat ed as an optimization program. The filter bank's PR feature can either be implicitly enforced through a set of mathematical relationships am ong the analysis filters' coefficients or through a set of constraints in the optimization program. The former approach results in a filter bank whose PR feature's dependency on hardware and software is elimina ted or, at least, minimized. The synthesis filters are then obtained b y a set of relationships that describe each synthesis filter as a func tion of the analysis filters, The criterion for optimality is ''least- squares,'' where the square of the difference between the ideal and ac tual frequency responses is integrated over the appropriate frequency bands for all M analysis filters and minimized.