10Gbps-光载射频技术的发展#
 

摘要：光载毫米波（ROF）接入技术以其通信容量大、接入方式灵活、覆盖范围广等优点成为下一代接入网中非常具有潜力的技术之一，近年来高清电视、物联网等业务的广泛开展要求通信网具有更高的接入速率，甚至达10Gbps 及其以上。本文介绍了10Gbps 及其以上传输速率光载射频（ROF）链路的关键技术及核心器件，通过与低速率技术及器件的比较，分析了其所能达到的性能参数；着重探讨了基于60GHz、120GHz、300GHz 等研究热点的ROF 系统的发展，分析了其性能优劣程度，通过相应的实例验证了10Gbps-ROF 技术应用的可行性。
 

关键词：光载射频技术；毫米波；10Gbps

0 引言
近年来，光载毫米波（ROF）技术以其大容量、低损耗、灵活接入等优点越来越受到人们的关注。作为宽带通信业务到用户的“最后一跳”，该技术兼具了光纤通信和无线通信的双项优势，既解决了光纤通信中分配方式繁冗，存在“电的瓶颈”等难题，同时还突破了传统无线通信系统的带宽和传输速率的限制，实现了光纤和无线网络的有机融合，被认为下一代非常有潜力的接入技术之一。
 

以前的研究报道中，毫米波频段多位于60GHz 以下，且信号传输也大多局限于1G—10Gbps。然而，随着新型业务的出现，通信容量迅速增加，据资料显示，下一代高清电视-UHDTV 和4-K TV 的分辨率增加为现有HDTV 的16 倍，所需的传输速率达24Gbps；同时，在现有的固网接入技术中，100Gbps 的以太网（Ethernet）和40Gbps 的无源光网络（Passive optical network）技术已处于标准化的过程，且固定无线接入、无线回程的传输速率已达1.5Gbps，而无线局域网（LAN）和个人局域网（PAN）的接入速率业已至数十吉比特每秒。因此10Gbps 及其以上传输速率的接入技术是未来无线通信发展的重要方向，也成为了ROF技术研究的热点。

本文将对10Gbps-ROF 技术进行描述，分为两个部分：核心技术及关键器件；系统发展。下面对其进行一一叙述。

3 结论
本文介绍了 10Gbps 及其以上ROF 链路的关键技术及核心器件，并对基于60GHz、120GHz、300GHz 等载波的ROF 系统的发展做了重要阐述，并通过具体的实例验证了此技术应用的可行性。随着ROF 技术的进一步发展，并与现今热点的THz 技术相结合，将会大大拓展接入系统的传输速率，推动宽带接入技术的发展。
 

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