h k ( n ) = C p 0 ( n ) cos [ ?? 2 T ( 2 k + 1 ) ( n - N - 1 2 ) + ?? k ] , ( 19 ) where k=0, 1, . . . , T???1, N is the length of the lowpass prototype filter po(n), C is a constant and ??k is a phase-angle that ensues alias cancellation between adjacent channels.