Patent ID: 6016212
Filing Date: 2000-01-18
Classification: H04B,H04J

Abstract:
A free-space wavelength division multiplexing system having a plurality of channels, each channel being associated with a light source of a different optical wavelength, the system having a first node at which the light sources of different optical wavelengths are multiplexed together into a multiplexed optical signal and a second node at which a user has electrical system components, the system comprising:free-space transmitter optics at the first node for launching the multiplexed optical signal into free space as a multiplexed optical beam;free-space receiver optics at the second node for receiving the multiplexed optical beam from free-space;a rotatable optical interference filter that receives the multiplexed optical beam from the free-space receiver optics and transmits a demultiplexed optical beam that corresponds to a single selected one of the channels and that has a single selected wavelength;a positioner for controlling the angular position of the interference filter with respect to the multiplexed optical beam to determine which channel is transmitted; anda photodetector for receiving the demultiplexed optical beam and providing corresponding output signals for the selected channel.