基于多阶差分相移键控的未来高速无源光网络平滑升级

Smooth Evolution to Future High-speed Passive Optical Network Based on Multi-ary DPSK

摘要:

针对无源光网络中高速传输和平滑升级问题，本文提出了一种基于多阶差分相移键控的无源光网络（passive optical networks ,PONs）向未来高速无源光网络平滑升级的方法。新PON信号应用多阶差分相移键控，从多阶差分相移键控调制的新PON信号到共存的调制的旧PON信号的串扰几乎被消除。利用多阶调制，新PON信号可通过目前商用带宽有限的收发器以高比特率传输。新PON信号应用波分复用技术倍增了下行带宽，由于利用多阶差分相移键控调制的下行信号对幅度键控重调制的上行信号产生较小的串扰，所以可以通过上行重调制实现透明光网络单元。通过仿真验证了基于6阶差分相移键控和基于8阶差分相移键控的方案，所有信号实现了无差错操作。新的PON下行信号对共存的旧PON下行信号和重调制后的上行信号产生的串扰很小，在现有的12.5 G级收发器中，新PON信号的比特率超过了每波长30Gb/s。

Abstract:

To achieve high speed transmission and smooth evolution simultaneously in passive optical networks (PONs), a smooth evolution from current passive optical networks to future high-speed PONs based on multi-ary differential phase shift keying (DPSK) is proposed. The new PON signal applies multi-ary DPSK. The crosstalk from the DPSK modulated new PON signal to the amplitude shift keying(ASK) modulated legacy PON signal in coexistence is almost eliminated. With multi-ary modulation, the new PON signal is transmitted at a high bit rate by current commercial bandwidth-limited transceivers. Wavelength division multiplexing (WDM) is applied to multiply the new PON downstream bandwidth and colorless optical network unit (ONU) is achieved by upstream remodulation because the downstream signal in DPSK modulation induces little crosstalk to the remodulated upstream signal in ASK modulation. A 6-ary DPSK based scheme and an 8-ary DPSK based scheme are demonstrated by simulation. Error-free operation is achieved for all signals. The new PON downstream signal induces very little crosstalk to the coexisting legacy PON downstream signal and the remodulated upstream signal. The bit rate of the new PON signal exceeds 30Gb/s per wavelength with current 12.5G-class transceivers.