Huang Shenjie, Chen Cheng, Bian Rui, Haas Harald, Safari Majid
Opt Lett. 2022 May 1;47(9):2294-2297. doi: 10.1364/OL.454994.
Photon counting detectors such as single-photon avalanche diode (SPAD) arrays can be used to improve the sensitivity of optical wireless communication (OWC) systems. However, the achievable data rate of SPAD-based OWC systems is strongly limited by the nonlinearity induced by the SPAD dead time. In this work, the performance of a SPAD-based OWC system with orthogonal frequency division multiplexing (OFDM) is investigated and compared with that of on-off keying (OOK). We employ nonlinear equalization, peak-to-average power ratio optimization by adjusting the OFDM clipping level, and adaptive bit and energy loading to achieve a record experimental data rate of 5 Gbps. The contrasting optimal regimes of operation of the two modulation schemes are also demonstrated.
诸如单光子雪崩二极管（SPAD）阵列之类的光子计数探测器可用于提高光无线通信（OWC）系统的灵敏度。然而，基于SPAD的OWC系统可实现的数据速率受到SPAD死区时间所引起的非线性的强烈限制。在这项工作中，研究了基于SPAD的采用正交频分复用（OFDM）的OWC系统的性能，并与开关键控（OOK）系统的性能进行了比较。我们采用非线性均衡、通过调整OFDM削波电平来优化峰均功率比，以及自适应比特和能量加载，以实现创纪录的5 Gbps实验数据速率。还展示了两种调制方案的对比最优工作模式。
