The performance of a bidirectional silicon mode-division (de)multiplexer has been analyzed in the radio over fiber passive optical network system. The device uses two grating-assisted contra-directional coupler sections to demultiplex the transmitted fundamental, first-order, and second-order quasi-transverse electric (TE) modes. A bandwidth of 791 GHz and acceptable crosstalks of −25.73 dB (TE0m), −10.30 dB (TE1m), and −11.84 dB (TE2m) have been achieved from the 2.5D finite-difference time-domain method at a wavelength of 1550 nm. The system uses parabolic index multimode fiber (MMF) and free-space optics channels alternatively. A 120-Gbps data rate has been obtained using differential quadrature phase-shift keying scheme and hybrid mode-division multiplexing techniques. The system maintains an acceptable bit error rate (≤10 − 12) over transmission distances of ≤5.3 km MMF and ≤1.9 km for free-space optics link with receiver sensitivities of ≥ − 26.2 and ≥ − 24.8 dBm, respectively.

中文翻译：

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硅光子在高速RoF / RoFSO通信中的光栅辅助无源分频多路复用器的性能分析

在光纤无源光网络系统的无线电中，已经分析了双向硅模式分割（de）多路复用器的性能。该器件使用两个光栅辅助的反向耦合器部分来解复用传输的基本，一阶和二阶准横向电（TE）模式。通过2.5D有限差分时域方法在1550 nm的波长下获得了791 GHz的带宽和-25.73 dB（TE0m），-10.30 dB（TE1m）和-11.84 dB（TE2m）的可接受串扰。 。该系统交替使用抛物线折射率多模光纤（MMF）和自由空间光学通道。使用差分正交相移键控方案和混合模分复用技术已获得120 Gbps的数据速率。