Built-in digital filter apparatus for physical layer of wireless intermediate-range sensing network

The invention relates and discloses an interpolating digital filter device which is applied to a wireless medium range sensor network physical layer, comprising an interpolating digital filter module based on FIR (Finite impulse response filter) and an interpolating digital filter module based on CIC (Cascaded integrator-comb filter). The interpolating digital filter module based on FIR comprises a shift register time delay module, a multiplication module, a coefficient selector module, and an accumulator module. Wherein, the accumulator module comprises a register module and an adder module. The interpolating digital filter module based on CIC comprises a pectinate unit module, an interpolating unit module and an integral unit module. The invention is characterized in occupying less hardware resource, being applied to higher system clock rate, smaller passband ripple, more stopband attenuation and so on. The invention is applicable to a broadband wireless transceiver, in particular to a wireless broadband transmission system based on OFDM (Orthogonal Frequency Division Multiplexing) in the mobile environment.