| 摘要 |
A communication device is disclosed which includes a first communication waveguide (10) and a second communication waveguide (40). A transmitter (16) launches signals into the first waveguide (10) and a detector D1 detects signals in the first waveguide (10). A second transmitter (42) launches signals into the waveguide (40) and a second detector D2 detects signals from the waveguide (40). Counter-propagating optical signals are launched into the first and second waveguides by transmitters (12) and (41) so that a first counter-propagating signal travels through the first and second waveguides in a first direction and a second counter-propagating signal travels through the first and second waveguides in a second direction. Amplifier assemblies (50) and (50') are provided in the first and second waveguides (10) and (40) and each assembly comprises an amplifier (51) for amplifying the optical signals and transmitting the signals in the first direction, a second amplifier (52) for amplifying the signals and for transmitting the signals in the second direction. The first and second amplifiers (51, 52) are arranged in parallel and coupled to the waveguides by first and second optical coupling devices. Thus, the counter-propagating optical signals which travel in the various directions are able to pass through the amplifier assemblies by passing through an appropriate one of the first or second optical amplifiers depending on the direction of travel of the counter-propagating signal. |
