IFIR Filters with Improved Efficiency for Filter Banks and Trans Multiplexers

In this paper, a new approach to design multiplier-free interpolated finite impulse response digital filter is presented. The approach is based on two step procedure, coefficient rounding and sharpening with no recursion equation. Interpolated finite impulse response approach is a very efficient method for designing sharp transition band filters. With this approach, filter with reduced number of multiplier coefficients is designed that permits efficient hardware implementation. The hardware complexity of the filter can be further reduced by employing rounding and sharpening technique. The prototype filter is formulated as a rounded and sharpened interpolated finite impulse response (R&S IFIR) filter. The prototype filter is then used to design the filter bank. Examples show that without introducing additional delay, the proposed approach provides better performance with reduced computational cost.