Lowpass minimum phase filter design using IFIR filters

A design procedure for minimum-phase FIR filters using an interpolated FIR (IFIR) filter is proposed. The IFIR technique allows two linear-phase filters of much lower order to be designed thereby making it easier to apply mipizing than is possible in high order FIR prototype filters. In this way, the problem of finding the roots of high order polynomials is overcome     

A new method for the design of IIR filters with flat magnitude response

This paper presents a new direct design of infinite-impulse response (IIR) filters with a flat magnitude response in both passband and stopband (Butterworth filters). The design specifications are passband and stopband frequencies and passband droop and stopband attenuation. The approach is based on an allpass filter with flatness at frequency points /spl omega/=0 and /spl omega/=/spl pi/. Depending on the parity of the IIR filter order, the allpass filter is either real or complex. However, in both cases, the resulting IIR filter is real.     

A new two-stage sharpened comb decimator

This paper presents a new sharpened comb decimator structure consisting of a cascade of a comb-filter based decimator and a sharpened comb decimator. The proposed realization scheme allows the sharpened section to operate at a lower rate that depends on the decimation factor of the first section. Using a polyphase decomposition, the subfilters of the first section can also be operated at this lower rate.     

One structure for fractional delay filter with small number ofmultipliers

A wide-bandwidth, high-resolution fractional delay filter (FDF) structure with a small number of multipliers per output sample and a short coefficient computing time is presented. The proposal is based on the use of a frequency FDF design method up to only half of the Nyquist frequency, in a multirate structure     

Low sensitivity second-order bandpass digital filter structure

A new low sensitivity second-order bandpass digital filter structure is presented. The proposed structure has the smallest absolute angle, sensitivity and a moderate radius sensitivity for the pole angle &thetas; in the range 0.38π ⩽ |&thetas;| ⩽ 0.44π and 0.56π ⩽ |&thetas;| ⩽ 0.62π and for the radius in the range 0.5 ⩽ r < 1