US Patent 7505686 Highly scalable multi-granular node architecture

Highly Scalable Multi-granular Node Architecture based upon strictly non-blocking waveband switch constructed around cyclic arrayed waveguide grating (AWG) routers. In one implementation, the invention includes a first N×N cyclic arrayed waveguide grating (AWG); a middle stage includes N tuner modules, and a second N×N cyclic AWG for routing information from a plurality of different optical networks. Another implementation of the invention further provides an add/drop switch, and a shuffler for performing add/drop functions and preserving the wavelength order.