Design of real and complex linear phase IIR filter banks

This paper presents a new direct method for the design of real and complex orthogonal IIR filter banks. The design is based on two complex allpass filters. The resulting filters have flat magnitude response in both, passband and stopband. The parameters of the design are the stopband frequency /spl omega//sub S/, and the stopband attenuation A/sub S/. Closed form equations for calculation of poles and zeros of the analysis filter bank are derived.