05115332 is referenced by 34 patents and cites 5 patents.

A receiver for coherent optical communication in a phase diversity system. An optical hybrid circuit receives a signal beam and receives a local-oscillator beam which has a predetermined phase shift. The optical hybrid circuit branches each beam into pairs, each pair having one signal beam and one local-oscillator beam. These beam pairs are output to first and second photodetectors which each apply a photoelectric conversion, thus producing first and second output signals. The output signals are output to an electrical 90.degree. hybrid circuit which shifts the first signal by 90.degree. and adds it to the second signal to produce a first output signal, and shifts the second signal by 90.degree. and adds it to the first signal to produce a second output signal. The first and second output signals are applied to first and second demodulators, respectively, which delay the signals by a delay corresponding to their frequency. The demodulators output the delayed signals to an adder which adds the two signals to produce an output signal. As a result, the receiver is capable of compensating the wavelength dispension is an optical fiber to secure an enhanced receiving sensitivity.

Title
Receiver for coherent optical communication
Application Number
7/553744
Publication Number
5115332
Application Date
July 18, 1990
Publication Date
May 19, 1992
Inventor
Hideo Kuwahara
Kawasaki
JP
Yoshihito Onoda
Kawasaki
JP
Tetsuya Kiyonaga
Kawasaki
JP
Shigeki Watanabe
Kawasaki
JP
Terumi Chikama
Machida
JP
Takao Naito
Kawasaki
JP
Agent
Staas & Halsey
Assignee
Fujitsu
JP
IPC
H04B 10/06
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