A design method for half-band FIR filters
Alan N. Willson, H. J. Orchard · IEEE Transactions on Circuits and Systems I Fundamental Theory and Applications · 1999
Present methods for designing half-band filters use iterative approaches such as the well-known Parks-McClellan algorithm or some variant of linear programming. Here we give a direct method using Chebyshev polynomials, which provides a reduction in design time over previous methods by about a factor of ten. For all practical purposes the response of the resulting filter is equal-ripple in both passband and stopband. A listing of a Fortran program for carrying out the design is included.