High speed frequency-shift keying decoder

摘要

A frequency-shift keying (FSK) signal detector splits an FSK signal into two paths. In one path, a phase-altering circuit having a variable frequency characteristic between the two encoding frequencies of the FSK signal provides either a phase lead or a phase lag depending upon the instantaneous frequency of the FSK signal. The phase-altered signal is sampled in response to the signal in the second path to decode a digital signal.