Wang Qiang, Huo Li, Xing Yanfei, Wang Dong, Chen Xin, Lou Caiyun, Zhou Bingkun
Opt Express. 2014 Feb 10;22(3):2798-806. doi: 10.1364/OE.22.002798.
A novel multifunctional frequency-doubling optoelectronic oscillator (FD-OEO) mainly based on a Mach-Zehnder modulator (MZM) cascaded with a phase modulator (PM) and a subsequent optical bandpass filter (OBPF) is proposed. We experimentally demonstrate simultaneous operations of frequency-doubled optical clock (FD-OC) recovery, low-duty-cycle dual-wavelength prescaled OC recovery and error-free fourfold time division demultiplexing with the proposed OEO injected with a 4 × 25-Gb/s optical time-division-multiplexing (OTDM) signal. We show that the proposed FD-OEO operates well for both the differential phase shift keying (DPSK) and on-off keying (OOK) modulation formats. The extracted dual-wavelength prescaled OC is proved to be nearly transform-limited with Gaussian-like shape. Furthermore, all four 25-Gb/s tributaries can be selectively demultiplexed by adjusting the phase shifters in the OEO loop. The power penalty at a bit error rate (BER) of 10(-9) is measured to be 2.4 dB, 1.2 dB for the best channel for DPSK signal and to be 2.5 dB, 1.1 dB for the best channel for OOK signal. In addition, as an extra benefit of the OEO, low-phase-noise prescaled electrical clock (EC) is also extracted.
提出了一种新型多功能倍频光电振荡器（FD-OEO），其主要基于与相位调制器（PM）和后续光学带通滤波器（OBPF）级联的马赫曾德尔调制器（MZM）。我们通过实验证明，在所提出的注入4×25 Gb/s光时分复用（OTDM）信号的OEO中，可同时实现倍频光时钟（FD-OC）恢复、低占空比双波长预分频OC恢复以及无误码四倍时分多路分解。我们表明，所提出的FD-OEO对于差分相移键控（DPSK）和开关键控（OOK）调制格式均能良好运行。所提取的双波长预分频OC被证明具有近似变换受限的高斯形状。此外，通过调整OEO环路中的移相器，所有四个25 Gb/s支路均可被选择性地多路分解。在误码率（BER）为10^(-9)时，DPSK信号最佳通道的功率代价测量值为2.4 dB、1.2 dB，OOK信号最佳通道的功率代价测量值为2.5 dB、1.1 dB。此外，作为OEO的一个额外优点，还提取了低相位噪声预分频电时钟（EC）。
