Title:
差分4位相偏移変調方式に対応した光受信器および光受信方法
Document Type and Number:
Japanese Patent JP4170298
Kind Code:
B2
Abstract:
In an optical receiver according to the present invention, an input signal light subjected to the differential quadrature phase shift keying (DQPSK) is incident on a PANDA type fiber in a linearly polarized state by 45°, so that a delay time difference corresponding to one symbol is generated between orthogonal polarization components in the DQPSK signal light, and then, the signal light is branched by a half mirror into two, to be sent to first and second paths respectively, thereby giving, by a 1/4 wave plate disposed on one of the paths, a relative birefringent amount difference of À/2 between the lights propagated through the respective paths. Then, each of the lights propagated through the first and second paths is separated into two orthogonal polarization components by a polarization beam splitter, and the respective polarization components are received by a differential reception circuit so that in-phase components and quadrature components in the DQPSK signal are demodulated. Thus, a small sized and low cost optical receiver capable of stably demodulating the DQPSK signal is provided.
Inventors:
Takeshi Hoshida
Application Number:
JP2005023741A
Publication Date:
October 22, 2008
Filing Date:
January 31, 2005
Export Citation:
Assignee:
富士通株式会社
International Classes:
H04B10/40; G02F2/00; H04B10/25; H04B10/50; H04B10/516; H04B10/548; H04B10/60; H04B10/61; H04B10/67; H04B10/69
Domestic Patent References:
| JP5268159A | ||||
| JP11041207A | ||||
| JP2004170954A | ||||
| JP2005020277A | ||||
| JP2004516743A |
Attorney, Agent or Firm:
Tomijio Sasashima