Tolerance of the frequency deviation of LO sources at a MIMO system

OPTICS COMMUNICATIONS

卷:354

Article

Xiao, Jiangnan¹  Li, Xingying¹  Zhang, Zirang¹  Xu, Yuming¹  Chen, Long¹  Yu, Jianjun¹ 

[1] Fudan Univ, Key Lab Informat Sci Electromagnet Waves, Shanghai 200433, Peoples R China

关键词: W-band;    Frequency difference;    MIMO;    Frequency offset estimation;    Heterodyne;    DSP;   

DOI  :  10.1016/j.optcom.2015.05.041

来源: Elsevier

【 摘 要 】

We analyze and simulate the tolerance of frequency offset at a W-band optical-wireless transmission system. The transmission system adopts optical polarization division multiplexing (PDM), and multiple-input multiple-output (MIMO) reception. The transmission signal adopts optical quadrature phase shift keying (QPSK) modulation, and the generation of millimeter-wave is based on the optical heterodyning technique. After 20-km single-mode fiber-28 (SMF-28) transmission, tens of Gb/s millimeter-wave signal is delivered. At the receiver, two millimeter-wave signals are down-converted into electrical intermediate-frequency (IF) signals in the analog domain by mixing with two electrical local oscillators (LOs) with different frequencies. We investigate the different frequency LO effect on the 2 x 2 MIMO system performance for the first time, finding that the process during DSP of implementing frequency offset estimation (FOE) before cascaded multi-modulus-algorithm (CMMA) equalization can get rid of the inter-channel interference (ICI) and improve system bit-error-ratio (BER) performance in this type of transmission system. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

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