Optical transmission apparatus and optical transmission method

Patent metadata

Field	Value
Publication number	US-2016337036-A1
Application number	US-201415110878-A
Country	US
Kind code	A1
Filing date	Jan 31, 2014
Priority date	Jan 31, 2014
Publication date	Nov 17, 2016
Grant date	—

Abstract

An optical emission unit includes a signal arrangement unit that generates respective pairs of phase-conjugate signals of a plurality of systems on the basis of externally input signals of a plurality of systems, mixes together the pairs of phase-conjugate signals, and then arranges the pairs of phase-conjugate signals discretely in orthogonally polarized electric fields, and an optical modulation unit that converts electric signals from the signal arrangement unit into optical signals and outputs the optical signals to the optical transmission unit, and the optical reception unit includes a photoelectric conversion unit that converts the optical signals transmitted by the optical transmission unit into electric signals, and a signal reconstruction unit that reconstructs the original signals of the plurality of systems by synthesizing the intermixed and discretely arranged signals from the photoelectric conversion unit.

First claim

1 . An optical transmission apparatus in which an optical emission unit and an optical reception unit are connected to each other via an optical transmission unit,
the optical emission unit includes: a signal arrangement unit that generates respective pairs of phase-conjugate signals of a plurality of systems on the basis of externally input signals of a plurality of systems, mixes together the pairs of phase-conjugate signals, and then arranges the pairs of phase-conjugate signals discretely in orthogonally polarized electric fields; and an optical modulation unit that converts electric signals from the signal arrangement unit into optical signals and outputs the optical signals to the optical transmission unit, and the optical reception unit includes: a photoelectric conversion unit that converts the optical signals transmitted by the optical transmission unit into electric signals; and a signal reconstruction unit that reconstructs the original signals of the plurality of systems by synthesizing the intermixed and discretely arranged signals from the photoelectric conversion unit.

2 . The optical transmission apparatus according to claim 1 , wherein the optical emission unit further includes an interference prevention unit that prevents mutual interference between the signals of the plurality of systems in advance.

3 . The optical transmission apparatus according to claim 2 , wherein the interference prevention unit allocates the signals of the plurality of systems to pulse shapes having a mutually orthogonal relationship.

4 . The optical transmission apparatus according to claim 1 , wherein the optical reception unit further includes an interference removal unit that removes mutual interference between the signals of the plurality of systems.

5 . The optical transmission apparatus according to claim 4 , wherein the interference removal unit suppresses interference between the signals of the plurality of systems allocated to the pulse shapes having a mutually orthogonal relationship so that the signals of the plurality of systems can be received independently by correlating the signals of the plurality of systems.

6 . The optical transmission apparatus according to claim 1 , wherein the optical emission unit further includes an emitted signal adjustment unit that performs at least one type of adjustment processing on an output from the signal arrangement unit, the adjustment processing including performing waveform equalization, spectral shaping, delay compensation, and differential delay addition on an emitted signal.

7 . The optical transmission apparatus according to claim 1 , wherein the optical reception unit further includes a received signal adjustment unit that performs at least one type of adjustment processing on an output from the photoelectric conversion unit, the adjustment processing including polarization separation, delay adjustment, equalization processing, and carrier wave frequency/phase recovery.

8 . An optical transmission method comprising: an optical emission step; and an optical reception step,
the optical emission step includes: a signal arrangement step for generating respective pairs of phase-conjugate signals of a plurality of systems on the basis of externally input signals of a plurality of systems, mixing together the pairs of phase-conjugate signals, and then arranging the pairs of phase-conjugate signals discretely in orthogonally polarized electric fields; and an optical modulation step for converting electric signals generated in the signal arrangement step into optical signals, and the optical reception step includes: a photoelectric conversion step for converting the received optical signals into electric signals; and a signal reconstruction step for reconstructing the original signals of the plurality of systems by synthesizing the intermixed and discretely arranged electric signals that have been converted in the photoelectric conversion step.

Assignees

• Mitsubishi Electric Corp

Inventors

• Yoshida Tsuyoshi

Classifications

• H04B10/532

  Polarisation modulation · CPC title

• H04B10/40

  Transceivers · CPC title

• H04B10/556 Primary

  Digital modulation, e.g. differential phase shift keying [DPSK] or frequency shift keying [FSK] · CPC title

• H04B10/2507 Primary

  for the reduction or elimination of distortion or dispersion · CPC title

• H04B10/616

  Details of the electronic signal processing in coherent optical receivers · CPC title