An receiver receives, amplifies, filters, and downconverts an RF signal to obtain an FM signal. The FM signal is then limited by a limiter and sampled by an ADC. The FM samples from the ADC are provided to an edge detector which detects transitions in the FM samples. The transitions correspond to zero...http://www.google.com/patents/US5910752?utm_source=gb-gplus-sharePatent US5910752 - Frequency demodulator with resampled output
