Patent ID: 6341021
Filing Date: 2002-01-22
Classification: H04B,H04J

Abstract:
A dynamic power equalization module for an optical network comprising:a wavelength-division-multiplexer having an optical input for receiving an optical data transmission containing a plurality of different channels each with correspondingly different wavelengths, wherein the wavelength-division-multiplexer spectrally separates the optical data transmission received by the optical input into parallel optical outputs which correspond to the different channels; a parallel array of acousto-optic modulators driven by RF acoustic signals connected to the optical outputs of the wavelength-division-multiplexer; a coupler which passively combines optical outputs from the parallel array of acousto-optic modulators such that the combined optical outputs from the parallel array of acousto-optic modulators is relayed to a plurality of coupler outputs corresponding to a feedback loop for the different channels and at least one coupler output corresponding to a dynamic power equalization module output; a plurality of optical filters connected to the coupler outputs corresponding to the feedback loop, each optical filter filtering out wavelengths that do not correspond to the channel in which they are being transmitted; a plurality photodetectors each receiving an output from corresponding optical filters such that the plurality of photodetectors produce signals representative of powers of the different channels; and, a dynamic control circuit which compares the signals produced by the plurality of photodetectors to determine relative power of the different channels and generates the RF acoustic signals that drive the parallel array of acousto-optic modulators such that each acousto-optic modulator dynamically controls each channels' transmission and reduces its power level to be substantially the same as that of a reference channel.