The HSP43216 Halfband Filter addresses a wide variety of applications by combining fS/4 (fS = sample frequency) quadrature up/down convert circuitry with a fixed coefficient halfband filter processor as shown in the block diagram. These elements may be configured to operate in one of the four following modes: decimate by 2 filtering of a real input signal; interpolate by 2 filtering of a real input signal; fS/4 quadrature down conversion of a real input signal followed by decimate-by-2 filtering to produce a complex analytic signal; interpolate-by-2 filtering of a complex analytic signal followed by fS/4 quadrature up conversion to produce a real valued output.