Compressed channel spacing for optical heterodyne communication systems

摘要

In an optical heterodyne communication system for transmission of multiple optical channels at different wavelenths, the optical channels are grouped into blocks for increased utilization of the available bandwidth. The spacing between optical channels within a block is typically equal to or somewhat greater than the channel bandwidth. The spacing between blocks is such that when the optical signal is heterodyned with a local oscillator lightwave, the interference with a selected optical channel from adjacent blocks does not exceed a predetermined level.