Pulse or digital communications – Spread spectrum – Direct sequence
Patent
1981-01-29
1984-01-17
Bookbinder, Marc E.
Pulse or digital communications
Spread spectrum
Direct sequence
375 87, H04L 700, H03K 5156
Patent
active
044267142
ABSTRACT:
A clock deriving system is disclosed. At a base radio station, data is converted to a Manchester code and modulated into an FM, PM or AM radio wave. This radio wave is received by the antenna of a radio receiving apparatus and amplified and demodulated by radio receiver of the apparatus into the base band signal of the Manchester code form. This signal is amplified and sliced by a limiter amplifier and then supplied to a clock derivation circuit where an effective clock component is derived. This clock component is passed through a filter of a necessary clock frequency band, from which clock information is produced. This clock information is applied to a phase detector where the output clock signal from a digital PLL and the input clock information are compared in phase, that is, detection is made of whether the former is ahead of or behind the latter. If the former signal is ahead of the latter, the phase detector produces "1", whereas if the former is behind the latter, the detector produces "0". As a result, the digital PLL adjusts the phase of the incorporated clock oscillator therein, thereby deriving the clock signal of the input data.
REFERENCES:
patent: 3112363 (1963-11-01), Schramel et al.
patent: 3611161 (1971-10-01), Claxton
patent: 3619505 (1971-11-01), Meile
patent: 3727202 (1973-04-01), Fort
patent: 3745248 (1973-07-01), Gibson
patent: 3949394 (1976-04-01), Kennedy
patent: 4267595 (1981-05-01), Hernandez
patent: 4363002 (1982-12-01), Fuller
Bookbinder Marc E.
Hitachi , Ltd.
LandOfFree
Clock signal derivation system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Clock signal derivation system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Clock signal derivation system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-703667