Wei Chia Chien, Chen Jason Jyehong
Department of Applied Materials and Optoelectronic Engineering, National Chi Nan University, 1 University Rd., Puli, Nautou, 545, Taiwan.
Opt Express. 2010 Sep 27;18(20):20774-85. doi: 10.1364/OE.18.020774.
While coherency between an RF-tone and OFDM signals in RoF systems at 60 GHz is de-correlated by fiber dispersion, both phase rotation term (PRT) on each subcarrier and inter-carrier interference (ICI) between subcarriers are induced at a receiver. We analytically calculate the powers of PRT and ICI under different parameters, such as subcarrier number, modulation format, laser linewidth and transmission distance. Moreover, dispersion-induced ICI is shown to be non-Gaussian distributed by its kurtosis, and its distribution depends on system parameters. Therefore, using only the power of ICI cannot predict accurate bit error rate (BER) and corresponding power penalty. We propose to use t-distribution to fit the distribution of ICI, and it can be used to compute BER precisely.
在60GHz的射频光纤（RoF）系统中，射频音调与正交频分复用（OFDM）信号之间的相干性会因光纤色散而解相关，此时在接收机处会在每个子载波上产生相位旋转项（PRT）以及子载波之间的载波间干扰（ICI）。我们通过分析计算了在不同参数（如子载波数量、调制格式、激光线宽和传输距离）下PRT和ICI的功率。此外，由色散引起的ICI通过其峰度显示为非高斯分布，并且其分布取决于系统参数。因此，仅使用ICI的功率无法准确预测误码率（BER）和相应的功率代价。我们建议使用t分布来拟合ICI的分布，并且它可用于精确计算BER。
