Coherent Optical DFT-Spread OFDM

Fanggang Wang; Xiaodong Wang

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arXiv · 1102.5641

Coherent Optical DFT-Spread OFDM

Fanggang Wang·Xiaodong Wang

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Abstract

We consider application of the discrete Fourier transform-spread orthogonal frequency-division multiplexing (DFT-spread OFDM) technique to high-speed fiber optic communications. The DFT-spread OFDM is a form of single-carrier technique that possesses almost all advantages of the multicarrier OFDM technique (such as high spectral efficiency, flexible bandwidth allocation, low sampling rate and low-complexity equalization). In particular, we consider the optical DFT-spread OFDM system with polarization division multiplexing (PDM) that employs a tone-by-tone linear minimum mean square error (MMSE) equalizer. We show that such a system offers a much lower peak-to-average power ratio (PAPR) performance as well as better bit error rate (BER) performance compared with the optical OFDM system that employs amplitude clipping.

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Fanggang Wang, Xiaodong Wang. 2011-02-28. Coherent Optical DFT-Spread OFDM. https://arxiv.org/abs/1102.5641

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