Multiplex communications – Wide area network – Packet switching
Patent
1986-11-06
1987-10-27
Olms, Douglas W.
Multiplex communications
Wide area network
Packet switching
375 88, H04J 102
Patent
active
047034769
ABSTRACT:
An audio program is encoded with a subaudible binary code. A first value bit (mark) is a first frequency signal and a second value bit (space) is a second frequency signal. The coded message includes an initialization period constituted by a signal having the mark frequency. In decoding, the mark and space signals are detected through first and second band pass filters specific to the mark and space signal frequencies. The mark and space frequencies are sufficiently different to permit separate filtering. The time duration for each bit of the code is substantial. The decoder through a phase locked loop and integrator reads the bit on the basis of the average value of the bit over the duration of the bit. A synchronization signal provides for synchronous reading of the code. This signal that initiates the decoding operation is generated only in response to the coincident detection of the initialization signal, the notch and a mark response at the phase locked loop.
REFERENCES:
patent: 3586781 (1971-06-01), Jones
patent: 3845391 (1974-10-01), Crosby
patent: 3885098 (1975-05-01), Dowling
patent: 3938156 (1976-02-01), Lunden
patent: 3947769 (1976-03-01), Rousos et al.
patent: 4311964 (1982-01-01), Boykin
patent: 4476577 (1984-10-01), Matzold et al.
Audicom Corporation
Bidco Inc.
Olms Douglas W.
LandOfFree
Encoding of transmitted program material does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Encoding of transmitted program material, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Encoding of transmitted program material will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1276485