Design of linear phase FIR filters with flat passband and flat or equiripple stopband magnitude response

Linear phase FIR filters with a magnitude response that is flat in the passband are desired in some applications. In this paper we present two solutions to the problem of designing linear phase FIR filters with a flat passband and specified bandwidth. First, by deriving conditions to attain desired degrees of flatness (or tangency) at ω=0 and/or ω=π, we obtain an analytical solution. We then present an iterative design procedure to obtain simultaneously a magnitude response that is flat in the passband and equiripple in the stopband