CIRCUIT FOR DEMODULATING FSK SIGNALS

摘要

A circuit and method of demodulating an FSK signal uses digital circuitry to convert the received signal into count values. For each reception an adaptive reference count value is determined by averaging the duration of received pulses during the preamble of the transmission. The adaptive reference count corresponds to a demodulated logic "1" or logic level "0". The counts from the coded portion of the transmission are compared to the adaptive reference count. If the count is within predetermined windows from the reference count, the count value is converted to the corresponding digital signal.