Patent ID: 6313934
Filing Date: 2001-11-06
Classification: G01M,H04B

Abstract:
A measurement scheme for characterizing chromatic dispersion of an optical system having a local access point and a remote access point, comprising:a first receiver intercepting a global positioning satellite (GPS) signal and deriving a first timing signal from the GPS signal;a signal generator coupled to the first receiver and generating a modulation signal synchronized to the first timing signal;an optical source providing an optical signal at predetermined optical wavelengths;a modulator coupled to the optical source, the signal generator, and the local access point, modulating the optical signal according to the modulation signal and providing a modulated optical signal to the local access point;a demodulator coupled to the remote access point of the optical system, receiving the modulated optical signal and producing a demodulated signal;a second receiver intercepting a GPS signal and deriving a second timing signal from the GPS signal;a second signal generator coupled to the second receiver and generating a reference signal synchronized to the second timing signal;a signal comparator coupled to the demodulator and the second signal generator, comparing the timing of the demodulated signal to the timing of the reference signal to determine the relative time delay between the demodulated signal and the reference signal at each of the predetermined optical wavelengths.