Title :
Diversity Combining for Asymmetrically Clipped Optical OFDM in IM/DD Channels
Author :
Chen, Liang ; Krongold, Brian ; Evans, Jamie
Author_Institution :
Dept. of Electr. & Electron. Eng., Univ. of Melbourne, Parkville, VIC, Australia
Abstract :
This paper looks at the problem of performance enhancement for orthogonal frequency-division multiplexing (OFDM) transmission in intensity modulated, direct detected (IM/DD) optical systems. Due to the unipolarity of the IM/DD channel, asymmetric clipping and associated biasing is inevitable, which results in a significant signal degradation. ACO-OFDM has been previously proposed to avoid this detrimental distortion with the cost of a lower spectral efficiency. In this paper, with the help of a detailed analysis of such distortion, a simple combining algorithm is proposed. This algorithm extracts the instructive information inside the clipping distortion, and requires no changes to the existing optical plant and no extra transmitting power. By exploiting this spectral diversity gain, the receiver SNR can be significantly improved.
Keywords :
OFDM modulation; diversity reception; optical communication; telecommunication channels; asymmetrically clipped optical OFDM; diversity combining; instructive information; intensity modulated/direct detected optical systems; orthogonal frequency-division multiplexing transmission; Algorithm design and analysis; Costs; Degradation; Diversity reception; Frequency division multiplexing; Intensity modulation; OFDM modulation; Optical distortion; Optical modulation; Optical receivers;
Conference_Titel :
Global Telecommunications Conference, 2009. GLOBECOM 2009. IEEE
Conference_Location :
Honolulu, HI
Print_ISBN :
978-1-4244-4148-8
DOI :
10.1109/GLOCOM.2009.5425293
