Patent ID: 6498665
Filing Date: 2002-12-24
Classification: H04J,H04Q

Abstract:
A system for dropping/adding wavelength division multiplexed optical signals including an input and an output for an optical multiplex signal between which are processors each of which is used for dropping an optical signal contained in one of â€œNâ€  of the â€œMâ€  channels of the incoming optical multiplex signal and adding an optical signal to the multiplex signal channel that is made available by the dropped signal, wherein each processor includes a drop optical filter and an add optical filter for an individual channel corresponding to a particular wavelength, an individual optical switch to which are connected a drop port of the drop filter, an individual add input, an individual drop output and an add port of the add filter, for dropping a signal from and adding a signal to a channel, and wherein, to transmit the multiplex signal from one filter to the other for the purposes of dropping/adding signals, the drop filters of the circuits are connected in series from the input of the system and in order of decreasing channel wavelength in a drop subsystem at the output of which the add filters are connected in series and in order of decreasing channel wavelength in an add subsystem, a multiplex signal output port of each filter being connected to a multiplex signal input port of the next filter in the series, between the input and the output of the system, to which the input port of the first drop filter and the output port of the last add filter are respectively connected.