Patent ID: 7162154

Claim:
A system for dispersion detection, comprising: an optical transmitter for transmitting an optical signal modulated relative to a signal parameter; and a receiver for receiving the optical signal, the receiver including a measuring module for measuring group transit time changes of the optical signal which are proportional to the signal parameter; wherein the optical transmitter transmits optical signal transmitting data having an optical frequency which is modulated by a frequency modulation signal routed to the optical transmitter to generate proportional group transit time changes of the optical signal in a presence of chromatic dispersion, the signal parameter being the optical frequency, and the measuring module determining the group transit time changes by comparing the transmitted data with a group transit time reference to measure the chromatic dispersion, and the measuring module includes a signal processing unit for synchronous demodulation of the group transit time changes of the optical signal which are proportional to the frequency modulation; and wherein the optical transmitter also includes at least one amplitude modulation part, which impresses an amplitude modulation on the optical signal, having a temporal relationship with the frequency modulation, and the signal processing unit includes a filter unit for synchronous demodulation which derives at least one reference signal from the amplitude modulation contained in a detected signal of the receiver obtained from the optical signal.