提出一种适用于正交频分复用-无源光网络(orthogonal frequency division multiplexing-passive optical network, OFDM-PON)符号同步的短训练序列, 通过对无线局域网中短训练序列的子载波分配方案进行调整, 将短训练序列的实时域信号非零均值调整为零均值, 解决了由于时域非零均值短训练序列拖尾干扰造成接收数据解调错误的问题. 仿真和实验结果表明, 该改进方法可以有效减少由短训练序列拖尾干扰引起的数据解调错误.
A short training sequences for orthogonal frequency division multiplexingpassive optical network (OFDM-PON) symbol synchronization is proposed. By adjusting the subcarrier allocation scheme of short training sequence in a wireless local area networks (WLAN), the mean of short training sequence signal in time domain is made from non-zero to zero, overcoming interference of receiving data demodulation caused by the wrong trail of the non-zero mean short training sequence in the time-domain. Simulation and experiments on data demodulation show that the improved method can effectively reduce training sequence interference errors caused by tailing.
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