Patent ID: 7787775
Filing Date: 2010-08-31
Classification: H04B

Abstract:
1. A control system comprising: an optical fiber; an optical filter on opposing ends of the optical fiber, said optical filter having a first port that couples with the optical fiber, a second port that couples an optical supervisory channel with the optical fiber and a third port that couples a transport channel with the optical fiber and where the optical filter separates the optical supervisory channel from the transport channel; at least one measurement module coupled to the optical fiber through the optical supervisory channel, the module includes circuitry to determine a transit time between first and second ends of a traffic carrying optical fiber when in a first mode, the module also includes circuitry to loop back a received optical signal when in a second mode and, where the module includes one of a hardware timer or a software timer to accumulate a representation of the transit time; and circuitry responsive to the determined transit time, to determine a degree of chromatic dispersion.