Abstract: A narrow band digital decimation filter that can be implemented on a single integrated circuit has a high order decimation filter that receives input digital data at P sampling rate and produces output digital data at Q sampling rate, where P>Q. The high order decimation filter can be a Hogenauer filter. A finite impulse response (FIR) filter, containing only a single multiplier and only a single accumulator, receives the output from the high order decimation filter at the now lowered sampling rate, and cleans up the frequency response of the high order decimation filter to provide narrow band filtering.