Inventors:
John C. Carrick - Wakefield MA, US
Stuart D. Brorson - Marlborough MA, US
Eric J. Frankfort - Yorktown Heights NY, US
Paul C. Talmadge - Ansonia CT, US
Roger P. Holmstrom - St. Charles IL, US
Assignee:
Tellabs Operations, Inc. - Naperville IL
International Classification:
H04B 10/04
Abstract:
Methods and apparatus for maintaining a pre-determined ratio of a pilot tone power and a total mean optical power of an optical signal are provided. One apparatus includes an optical source coupled to provide an optical signal in response to a DC bias and an AC bias corresponding to a pilot tone signal. A processor is coupled to compute each of an AC component and a DC component of the optical signal from the same digitally sampled signal. A feedback control is coupled to vary at least one of the DC bias and the AC bias in accordance with a difference between a pre-determined value and a ratio of the AC and DC components.