Wu Binqi, Lu Jin, Gao Mingyi, Ren Hongliang, Le Zichun, Qin Yali, Guo Shuqin, Hu Weisheng
College of Information Engineering, Zhejiang University of Technology, Hangzhou 310023, China.
School of Electronic and Information Engineering, Soochow University, Suzhou 215006, China.
Sensors (Basel). 2020 Nov 9;20(21):6397. doi: 10.3390/s20216397.
A blind discrete-cosine-transform-based phase noise compensation (BD-PNC) is proposed to compensate the inter-carrier-interference (ICI) in the coherent optical offset-quadrature amplitude modulation (OQAM)-based filter-bank multicarrier (CO-FBMC/OQAM) transmission system. Since the phase noise sample can be approximated by an expansion of the discrete cosine transform (DCT) in the time-domain, a time-domain compensation model is built for the transmission system. According to the model, phase noise compensation (PNC) depends only on its DCT coefficients. The common phase error (CPE) compensation is firstly performed for the received signal. After that, a pre-decision is made on a part of compensated signals with low decision error probability, and the pre-decision results are used as the estimated values of transmitted signals to calculate the DCT coefficients. Such a partial pre-decision process reduces not only decision error but also the complexity of the BD-PNC method while keeping almost the same performance as in the case of the pre-decision of all compensated signals. Numerical simulations are performed to evaluate the performance of the proposed scheme for a 30 GBaud CO-FBMC/OQAM system. The simulation results show that its bit error rate (BER) performance is improved by more than one order of magnitude through the mitigation of the ICI in comparison with the traditional blind PNC scheme only aiming for CPE compensation.
提出了一种基于离散余弦变换的盲相位噪声补偿（BD-PNC）方法，用于补偿基于相干光偏移正交幅度调制（OQAM）的滤波器组多载波（CO-FBMC/OQAM）传输系统中的载波间干扰（ICI）。由于相位噪声样本可以通过离散余弦变换（DCT）在时域中的展开来近似，因此为该传输系统建立了一个时域补偿模型。根据该模型，相位噪声补偿（PNC）仅取决于其DCT系数。首先对接收到的信号进行公共相位误差（CPE）补偿。之后，对一部分具有低判决错误概率的补偿信号进行预判决，并将预判决结果用作发射信号的估计值来计算DCT系数。这种部分预判决过程不仅降低了判决错误，还降低了BD-PNC方法的复杂度，同时保持了与对所有补偿信号进行预判决时几乎相同的性能。进行了数值模拟，以评估所提出方案在30 GBaud CO-FBMC/OQAM系统中的性能。仿真结果表明，与仅针对CPE补偿的传统盲PNC方案相比，通过减轻ICI，其误码率（BER）性能提高了一个多数量级。
