Performance monitoring and fault location in optical transmission
US5654816A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 6, 1996 |
| Grant date | Aug 5, 1997 |
| Priority date | — |
| Expiry date | Jun 6, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J14/0298
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Monitoring of optical amplifiers is accomplished, in accordance with the invention, by an apparatus and method for detecting a power level of a tone modulated upon a signal input to the amplifier, detecting an output power level of the amplifier, and comparing the power level of the tone to the output power level of the amplifier to determine an indication of the performance of the amplifier. In illustrative embodiments of the invention, each of the individual channels within a multiplexed optical signal are modulated with a specific low-frequency tone. The modulating is performed at the transmission site of the optical signal, and the specific tone frequencies are chosen to be lower than the low-frequency cut-off of any other information encoded upon the optical signal. The channel power of each channel is determined after each stage of optical amplification in the network by measuring the power of its respective unique low-frequency tone using a low-cost monitor. The total optical output power of the optical amplifier is also measured by the monitor. The ratio between the tone power and the optical amplifier output power after the first stage of optical amplification in the netwo…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.