Cheng Lin, Wen He, Zheng Xiaoping, Zhang Hanyi, Zhou Bingkun
State Key Laboratory on Integrated Optoelectronics, Department of Electronic Engineering, Tsinghua University, Beijing, 100084, China.
Opt Express. 2011 Sep 26;19(20):19129-34. doi: 10.1364/OE.19.019129.
A novel OFDM-PON structure based on channel characteristic division is proposed to reduce the sampling and computation requirement at the ONUs. In this method, the preprocessed downstream signal propagated to the ONUs is diversely aliased on spectrum by the sub-Nyquist sampling. With the subcarriers in OFDM symbols distorted according to the channel characteristics and overlaid by sections, users can recover the expected original data sent to the specific ONU lossless. Based on this method, the receiving capability of one of the 32 ONUs in a 40-Gb/s 32-QAM channel characteristic division OFDM-PON experiment is tested. The experiment confirms that the sampling rates and FFT sizes can be reduced to 1/32 on average compared to the conventional method. This new method also supports dynamic bandwidth allocations and improves the system efficiency and security by realizing the addressing process in the physical layer.
为降低光网络单元（ONU）的采样和计算需求，提出了一种基于信道特性划分的新型正交频分复用无源光网络（OFDM-PON）结构。在该方法中，传播到ONU的预处理下行信号通过亚奈奎斯特采样在频谱上进行不同的混叠。通过根据信道特性使OFDM符号中的子载波失真并按段叠加，用户可以无损恢复发送到特定ONU的预期原始数据。基于此方法，在一个40 Gb/s 32正交幅度调制（QAM）信道特性划分OFDM-PON实验中测试了32个ONU之一的接收能力。实验证实，与传统方法相比，采样率和快速傅里叶变换（FFT）大小平均可降低至1/32。这种新方法还支持动态带宽分配，并通过在物理层实现寻址过程提高了系统效率和安全性。
