Impact of Quadrature Imbalance in Optical Coherent QPSK Receiver

Author

Chang, Sun Hyok ; Chung, Hwan Seok ; Kim, Kwangjoon

Author_Institution

Opt. Transm. Team, Electron. & Telecommun. Res. Inst., Daejeon

Volume

21

Issue

11

fYear

2009

fDate

6/1/2009 12:00:00 AM

Firstpage

709

Lastpage

711

Abstract

In this letter, we present the impact of quadrature imbalance in an optical coherent quadrature phase-shift-keying (QPSK) receiver. Arbitrary conjugate misalignment was realized in all-fiber optical hybrid and two correction algorithms of quadrature imbalance, the ellipse correction method, and the Gram-Schmidt orthogonalization method, were independently applied. Bit-error-rate curves versus optical signal-to-noise ratio (OSNR) were measured for the 20-Gb/s optical QPSK signal. We show that OSNR penalty is reduced from ~6 to 1 dB at ~20deg conjugate misalignment with the help of correction algorithms.

Keywords

error statistics; optical receivers; quadrature phase shift keying; Gram-Schmidt orthogonalization method; all-fiber optical hybrid; arbitrary conjugate misalignment; bit-error-rate curves; correction algorithms; ellipse correction method; optical coherent QPSK receiver; optical signal-to-noise ratio; quadrature imbalance; quadrature phase-shift-keying; Optical fiber communication; optical fiber devices;

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/LPT.2009.2016759

Filename

4801709