可见光通信（VLC）有效结合了发光二极管（LED）的绿色照明和通信两大优点，是无线光通信的研究热点之一。基于相机VLC系统（简称OCC系统）在智能手机越来越普及的潮流下受到了广泛的关注和研究。OCC系统以照明LED为信号光源而以相机中图像传感器（IS）为信号接收器件，具有天然空间分集接收能力，因此具有广泛的应用前景。由于IS与传统光电二极管（PD）在可见光信号的接收与处理过程有明显不同，原有基于PD的VLC相关通信技术无法直接应用于基于IS的VLC系统。本文阐述了OCC系统的关键技术，并给出了相关应用场景。
Visible light communication (VLC) technology, which provides green lighting and data communication functions, is one of the most vibrant research topics in optical wireless communications. Since the popularity of smartphones, imaging sensor-based VLC (or optical camera communication, OCC) is receiving more and more attention and investigation. Such OCC technology has the ability to separate light signals coming from the different angles of incidence, thus shows an extensive application prospect in many areas. The OCC has lots of differences from the traditional single photodiode-based VLC system, not only in signal processing filed but also in modulation and other domains. Therefore, we have to develop dedicated techniques to support the OCC. This paper reviews some key techniques in OCC system, and discusses the application scenarios of this system.
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