Digital filtering of band-pass signals with phase-quadrature mixing

摘要

The in-phase and quadrature channels are mixed (IQM1) with a quarter of the sampling rate of the input signal. A single interpolator (IP1) calculates the sample values of the Q channel. The samples from both channels are balanced prior to half-band filtering (HBF1) and decimation (DZ1). An I-Q re-mixer (IQR1) then combines the two partial signals into a single output, at a sampling rate which is only half of the decimated sampling rate in the separate channels.