Chebyshev IIR filter sharpening implemented on FPGA
Vladimir M. Poučki, M.D. Lutovac · 2008
Filter design technique called filter sharpening (a new filter created from an existing filter in which the passband ripple is reduced and the stopband attenuation is increased) is presented. The proposed method is applied on the Chebyshev infinite impulse response (IIR) filter whereas in the past the 30 year old technique had been applied only to FIR filters with constant group delay. Using a small area of field programmable gate array chips for placing only two fourth-order IIR filters, and the hardware folding techniques, a number of different filter specifications can be fulfilled. The method is attractive for filter designs without extensive analysis of nonlinear effects and for the fixed point implementations.