VLC performs the dual-functions of communication and lighting and will play an important role in next-generation wireless communications. Proper multiple access methods should be identified for VLC in multi-user scenarios. This article proposes a VLC-CDMA system using OCCs, which are unipolar codes with a multiple sub-codes structure. OCCs offer good autocorrelation and cross-correlation functions. The issues on encoding criteria and application of OCCs in VLC-CDMA systems are discussed. The transmitters use LEDs with different wavelengths to distinguish different sub-codes. Compensator circuits are used to achieve equal gain combining at receivers to exploit the good correlation properties of OCCs. The receivers use the filters with different center wavelengths to distinguish different sub-codes. The performance of VLC-CDMA systems with OCC is compared to OOCs and multi-carrier CDMA systems, to verify that the proposed system is robust for its applications in multi-user scenarios.

中文翻译：

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基于光互补码的VLC-CDMA系统

VLC执行通信和照明的双重功能，并将在下一代无线通信中发挥重要作用。在多用户方案中，应为VLC确定正确的多种访问方法。本文提出了一种使用OCC的VLC-CDMA系统，该系统是具有多个子代码结构的单极性代码。OCC提供了良好的自相关和互相关功能。讨论了有关VLC-CDMA系统中OCC的编码标准和应用的问题。发射器使用具有不同波长的LED来区分不同的子代码。补偿器电路用于在接收器处实现相等的增益组合，以利用OCC的良好相关性。接收器使用中心波长不同的滤光片来区分不同的子码。