Pulse or digital communications – Repeaters – Testing
Patent
1989-10-24
1992-03-17
Safourek, Benedict V.
Pulse or digital communications
Repeaters
Testing
375 85, 329350, 455257, H04L 2706, H04L 2716
Patent
active
050974874
ABSTRACT:
A digital demodulator or receiver (22) having an interface (24) for receiving an input signal modulated with digital data, a multiplier (36) for multiplying the input signal with a local oscillator signal (LO) to generate a product signal, and an integrator (38) for periodically integrating the product signal to generate a sequence of integrated signals, each having an amplitude indicative of a respective portion of the digital data, additionally includes a circuit (30, 32) for directly generating a plurality of logic signals and a summer (34) for summing the logic signals to directly synthesize the local oscillator signal (LO). The local oscillator signal (LO) thereby produced has a fundamental component and third and fourth harmonic components and is shaped to ensure that each of the third and fourth harmonic components has an amplitude substantially less than that of the fundamental component. The disclosed circuit includes a reset mechanism (RESYNC) which quickly adjusts phase of the local oscillator signal (LO) by modifying the phase of the directly generated logic signals.
REFERENCES:
patent: 3368036 (1968-02-01), Carter et al.
patent: 4295098 (1981-10-01), Crowley
patent: 4328555 (1982-05-01), Mantione
patent: 4344176 (1982-08-01), Qureshi
patent: 4535459 (1985-08-01), Hogge, Jr.
patent: 4625180 (1986-11-01), Kamakura et al.
patent: 4649551 (1987-03-01), Sander et al.
patent: 4667170 (1987-05-01), Lofgren et al.
patent: 4677395 (1987-06-01), Baker
patent: 4689581 (1987-08-01), Talbot
patent: 4712077 (1987-12-01), Ansell et al.
patent: 4809306 (1989-02-01), Somer
"Carrier Synchronization and Detection of QASK Signal Sets", by Simon and Smith, IEEE Tran. on Comm., vol. 22, Feb. 1974, pp. 98-106.
"Offset Quadrature Communications with Decision-Feedback Carrier Synchronization", by Simon and Smith, IEEE. Tran. on Comm., vol. 22, Oct. 1974, pp. 1576-1584.
"A Bandwidth Compressive Modulation System Using Multi-Amplitude Minimum Shift Keying (MAMSK)", by Weber et al., IEEE Tran. on Comm., vol. 26, 1978, pp. 543-551.
Bocure Tesfaldet
Safourek Benedict V.
LandOfFree
Local oscillator signal generating system for digital demodulato does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Local oscillator signal generating system for digital demodulato, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Local oscillator signal generating system for digital demodulato will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1481689