  The sinc function is often used as the basis for the design of discrete
linear-phase FIR filters. However the Fourier transform of the truncated sinc
function exhibits ripple in the pass band due to the Gibbs phenomenon. This
paper introduces an alternative function based on Chebyshev polynomials whose
Fourier transform decreases monotonically in the pass band. Furthermore this
function features an intrinsic window function with an adjustable parameter
influencing the Fourier transform in the transition and stop bands.
