DIGITAL FM DEMODULATOR

摘要

In a preferred embodiment, an FM demodulator includes an I and Q sampler for generating data samples of I and Q signals of an FM signal. A si gnalprocessor derives samples of a modulating waveform o f the FM signal from the I and Q data samples, using a Lagrangian interpolation function of the I and Q data samples. Variables include derivatives of the I and Q signals obtained by differentiation of the Lagrangian function. Preferably, the processor furthe r utilizes a correction factor to correct the modulating waveform samples obtained from theLagrangian-based interpolation, to thereby derive a modulating waveform exhibiting low signal distortion.