Coherent optical OFDM system (CO-OFDM) is a promising technology in high speed long-haul optical transmission. Polarization dependent loss (PDL) and first-order polarization mode dispersion (PMD) influence system performance seriously in high speed transmission. The mathematical model of transmission is analyzed, and a signal equalization scheme is proposed for CO-OFDM systems. Numerical simulation is done to validate the method and the estimation algorithm. Analysis and simulation results show that the polarization effect may cause amplitude noise and phase noise, which can be eliminated with signal equalization. At a length of 720 km, the Q value is improved by 0.8 dB for = 1 compared with = 0.5. Meanwhile, the first-order PMD may reduce the PDL effect by rotation of SOP (state of polarization).
HAO Yao-hong1, LENG Dan1, FANG Tao2
. Polarization Dependent Loss in Coherent Optical Systems[J]. Journal of Applied Sciences, 2014
, 32(1)
: 39
-43
.
DOI: 10.3969/j.issn.0255-8297.2014.01.007
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