System and method for phase-synchronous, flexible-frequency clocking and messaging
US5805871A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 21, 1995 |
| Grant date | Sep 8, 1998 |
| Priority date | — |
| Expiry date | Jul 21, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J3/0685
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A master time-base unit generates quadrature-phase sinusoidal system reference signals that are phase-locked to a frequency reference oscillator. Based upon messaging signals received from an external source, each system reference signals is modulated according to direct carrier amplitude modulation, and is distributed to local time-base units via a transmission line. Within each local time-base unit, local reference signals and an offset signal are generated, where the local reference signals are phase-locked to the modulated system reference signals. A local reference signal and the offset signal are mixed to generate a local timing signal via frequency upconversion. A frequency-divided version of the local timing signal is phase-locked to a frequency-divided version of a local reference signal. Reprogrammable frequency dividers in combination with phase-lock facilitate the programmable specification of local timing signal frequencies. Within each local time-base unit, the modulated system reference signals are synchronously demodulated to produce bit sequences. The bit sequences are converted into synchronous messages and/or synchronous data, facilitating system-wide broadcast-t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.