Telegraphy – Systems – Printing
Patent
1976-02-13
1977-03-08
Richardson, Robert L.
Telegraphy
Systems
Printing
325 56, 325 59, 178 691, 179 15BS, H04J 100, H04L 700, H04L 2710
Patent
active
040115119
ABSTRACT:
In a digital data link system which transmits and receives frequency-shift keyed digital data over mark/space frequency channels, the invention enhances system performance in the presence of noise. The method utilizes two synchronization channels, selecting the better one to synchronize the receiver to the transmitter. The method teaches the accumulation of the results of a plurality of data-state determining measurements and the utilization of the accumulated measurements made during a baud interval to resolve the received mark/space frequency signal into a corresponding mark/space data-state signal. Apparatus to practice the method is described. The apparatus includes a timing recovery circuit for synchronization-channel selection and a digital frequency detector capable of extracting information from a data signal in the presence of noise having the same frequency as the data signal and up to 86.6% of the amplitude of the data signal.
REFERENCES:
patent: 2899548 (1959-08-01), Boughtwood et al.
patent: 3622885 (1971-11-01), Kruszynski et al.
patent: 3846708 (1974-11-01), Franco
Duffy James F.
Kesterson James C.
Richardson Robert L.
The Singer Company
LandOfFree
Frequency-shift digital data link and digital frequency detectio does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Frequency-shift digital data link and digital frequency detectio, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Frequency-shift digital data link and digital frequency detectio will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1408933