Design of narrow-band Laguerre filters using a min-max criterion

As an alternative to conventional FIR filters, IIR filter architecture based on orthonormal Laguerre functions is proposed for applications in narrow-band filtering. A Laguerre IIR filter design methodology is presented via a frequency transformation in the digital domain. The Laguerre filter can then be efficiently designed using a min-max criterion via a modified Parks-McClellan (1972) FIR filter design algorithm. The proposed Laguerre IIR filter architecture is easy to implement because it needs only a small number of components and therefore well suited for VLSI circuits. The impact of the selection of filter pole on the filter stability and phase linearity is discussed in the paper. The robustness issue of the narrow-band Laguerre IIR filter is also addressed.