LCOS-based WSS with true integrated channel monitor for signal quality monitoring applications in ROADMs

We propose and demonstrate a novel LCOS based WSS architecture with independent operation of two WSS switches in a single optical device to enable cost effective integrated monitoring of signal quality at any desired point in a ROADM. Only a very minor dimensional change to the optical train is required to separate the operation of a number of ports to be used for the monitoring application. The monitor ports can switch independently of the WSS and can even operate on different channel bandwidths or Grids. The independently filtered light path can be made available for power measurements in the first case or for full signal quality measurements.