Pulse or digital communications – Spread spectrum – Direct sequence
Patent
1985-03-29
1987-03-24
Griffin, Robert L.
Pulse or digital communications
Spread spectrum
Direct sequence
375118, 307518, 328118, H04L 702
Patent
active
046530754
ABSTRACT:
A bit synchronizer for a BPSK input signal having a sinusoidal carrier frequency f that is much greater than the modulating signal bit rate. The synchronizer comprises means (29, 31) for repetitively sampling the amplitude of the input signal over a preselected sampling interval portion of each modulating signal bit period (T). For each sampling interval, three numbers are recorded: N1, the total number of samples; N2, the number of samples that do not change sign with respect to a reference sample; and N3, the number of samples that do change sign with respect to the reference sample. When the number of samples not changing sign exceeds a preselected threshold value, which takes into account noise corruption of the input signal, bit synchronization is declared, a synchronized output clock (39) is generated, and digital data having a 180.degree. ambiguity is sent to subsequent ambiguity resolution means. When synchronization has not yet occurred, and the last sample changed sign, a phase circuit 34 is adjusted to shift in the proper direction a local clock (38), causing time-shifting of the sampling interval window prior to examination of the next modulating signal bit period (T).
REFERENCES:
patent: 3551816 (1970-12-01), Paine
patent: 4146743 (1979-03-01), Raynham
patent: 4246653 (1981-01-01), Malm
patent: 4246654 (1981-01-01), Malm
patent: 4247943 (1981-01-01), Malm
patent: 4290140 (1981-09-01), Malm
patent: 4385395 (1983-05-01), Tanaka et al.
patent: 4457005 (1984-06-01), Burke et al.
Houston, S. W., et al., "Microprocessor Bit Synchronizer for Shuttle Payload Communications", IEEE Transactions on Communications, vol. COM-26, No. 11, Nov. 1978, pp. 1594-1603.
Ford Aerospace & Communications Corp.
Griffin Robert L.
Huseman M.
Radlo Edward J.
Sadler Clifford L.
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