Patent ID: 7123841
Filing Date: 2006-10-17
Classification: H04B

Abstract:
1. A transmission system for transmitting controlled phase optical signals modulated at the timing rate of a clock of period T which defines successive time cells defining in the signal low levels or high levels of modulation of an optical carrier wave of optical frequency F 0 , said signal having an optical phase shift in each time cell which defines a low power level and which precedes or follows a cell which defines a high power level, said system comprising: an optical link adapted to transmit said controlled phase signal from an entry end of the link to an exit end of the link; and optical corrector means coupled to said exit end and/or inserted at one or more points of said optical link, wherein said corrector means applies optical filtering to the signal at said exit end and/or at said points of said optical link, said filtering being set to compensate widening of a spectrum that said controlled phase signal might suffer because of phase self-modulation as the signal is transmitted in said optical link, and wherein said corrector means does not include a reactor and comprises at least one filter having an effective transfer function expressing variations as a function of the optical frequency F of a transmission coefficient of the optical link that is approximately Gaussian in a vicinity of F