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路振龙王军华孙彦赞汪敏方勇 《光学学报》2013,(10):33-39
受多种光纤非线性因素的影响,基于正交频分复用(OFDM)技术的无源光网络(PON)会受到较为严重的载波间干扰(ICI)。为了抑制OFDM-PON系统中的上述问题,构造了一种新的伪对称序列(PST),并提出将该问题转化为求解两个Toeplitz子系统,然后对其中一个子系统的解进行预处理,将其转化为另一子系统的输入,之后利用最小二乘准则对子系统求解,从而达到抑制载波间干扰的目的。在算法实现过程中,利用所构造序列的伪对称特性和快速傅里叶变换(FFT),避免了高阶矩阵直接求逆,从而提升了算法实时性。仿真结果表明,该方法不仅能够有效抑制OFDM-PON系统的载波间干扰,而且能有效提升该算法的实时性能。 相似文献
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在240℃水热体系中首次合成出系列纳米晶固溶体(CeO 相似文献
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Using the 2.6-3.8 GHz solar radio spectrometer of the National Astronomical Observatories of China (NAOC), a pair of microwave millisecond spike (MMS) emissions were observed, and their frequency drift rate was measured. The separatrix frequency of the MMS pair was at 2900 MHz. Its emission layer was about 2×104km above the photosphere. The polarization degree was wave-like variation with an average value of about 25% in LCP. An MMS pair differs greatly from the type III bursts pair. For the latter, in a certain frequency range, there is no emission around separatrix frequency. This phenomenon may help better understand the mechanism of MMS. 相似文献