Bit and frame synchronization unit for an access node of optical transmission equipment
US5220448A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 2, 1991 |
| Grant date | Jun 15, 1993 |
| Priority date | — |
| Expiry date | Dec 2, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L7/10
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
The bit and frame synchronization unit (51) serves for the synchronization of an access node to the bit stream running along an optical fiber. The unit (51) comprises an optical switching element (57) which can be controlled electrically and serves as a light switch. It further comprises a sequence generator (75) for electrically controlling the switching element (57), a clock generator (72), an optoelectrical transducer (60), an electrical integrator (63), a regulator and evaluator (66) and a control unit (69). In addition, there is a coarse regulator (48). An optical bit pattern (BM) occurs periodically at the input (53), an equivalent electrical comparison pattern (VM) assigned to the latter occurs at the control input (44). The level of the resultant electrical voltage pulse U at the output (64) of the integrator (63) is a measurement for the respective relative phase deviation during approximate synchronous running. There is a sharp pulse maximum during absolute synchronous running. The unit (51) serves for the simultaneous synchronization of the bit and frame clock.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.