This paper proposes a novel return light cancellation technique using an adaptive interference equalizer in the wavelength division multiplexed passive optical network (WDM–PON) transmission system employing the single-wavelength bidirectional transmission scheme. In this scheme, the same wavelength is assigned to both the uplink and the downlink. In other words, the number of the wavelengths allocated to optical network units can be half compared with a typical PON system. However, this presents us with a problem in that the reflected component of the transmitted signal light interferes with the received signal light. We investigated the performance of the proposed interference canceling equalizer using back-to-back transmission simulation and a dual-polarization-quadrature-phase-shift-keying signal transmission experiment. The results indicated that the proposed adaptive equalizer enabled reception with no error when the OSNR was sufficiently large, even when the power of the interfering light was large (i.e., SIR $\geq$ 2 dB).

中文翻译：

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单波长双向WDM-PON传输系统的光反射干扰均衡

本文提出了一种在采用单波长双向传输方案的波分复用无源光网络（WDM-PON）传输系统中使用自适应干扰均衡器的新型回波消除技术。在该方案中，将相同的波长分配给上行链路和下行链路。换句话说，分配给光网络单元的波长的数量与典型的PON系统相比可以减少一半。但是，这给我们带来了一个问题，即发射信号光的反射分量会干扰接收信号光。我们使用背对背传输仿真和双极化正交相移键控信号传输实验研究了所提出的干扰消除均衡器的性能。$ \ geq $ 2 dB）。