水下高速无线光通信系统的若干关键技术研究

The family of underwater optical wireless communication (UOWC) technologies is one of the key enablers for supporting information detection, collection and transmission of ocean resources. It overcomes the restrictions imposed by optical fiber communication regarding underwater activities of communication equipment, as well as the disadvantages of traditional underwater acoustic communication technologies, such as limited bandwidth, low transmission rate, long latency, etc. Since UOWC systems can support dynamic and high-speed communications between underwater devices, they are therefore of vital and practical significance for implementing various applications, for example detection of ocean resources and environmental pollutions, measurements on undersea volcanic activities and earthquakes, marine navigations, defense and military activities, and so on. UOWC is one of the major technologies for implementing the national strategy of South China Sea. Currently, the development of UOWC techniques is still at the preliminary stage, and the achievable capacity and reliability of information transmissions in UOWC systems are still far less than those of terrestrial radio systems. In line with the development of the comprehensive platform project of the scientific research ship "Zhong Shan No. 1", which has been proposed and to be built by Sun Yat-sen University, as well as benefitting from the distinct advantages of coastal locations of the Guangdong Province and the Guangzhou City, in this research project we aim to initiate in-depth theoretical research on selected important aspects of UOWC systems. More specifically, the scope of the project includes research on modulation and coding schemes, channel estimation and signal detection, peak-to-average power ratio reduction, as well as the implementation of a testing and performance evaluation prototype for UOWC systems, with the objective of trying to achieve fundamental breakthroughs and mastery of these key technologies.

水下无线光通信技术是支持对海洋资源的信息探测、采集与传输的关键技术之一，它克服了水下有缆通信对通信实体活动范围的限制，以及传统水声通信技术存在的带宽小、传输速率低、时延大等缺点，可支持水下设备节点之间的动态、高速通信。掌握水下无线光通信的核心技术，在实现海洋资源探测、环境污染监测、海底火山与地震测量、航海安全、国防军事应用等方面有着重要的现实意义，是实施国家“南海战略”的关键技术支撑之一。目前水下无线光通信技术仍处于初期发展阶段，水下设备的信息传输仍远达不到陆地无线通信系统的高容量与高可靠性。本项目依托中山大学筹建的“中山一号”大型综合科考船项目平台，充分利用广东省、广州市本地的沿海地域优势和学校大平台的实验条件，深入研究水下无线光通信系统的调制编码、信道估计与信息检测、峰均比抑制等关键理论与技术问题，并搭建水下光通信系统原型的测试与验证平台，力求突破并掌握该领域的若干关键技术。

水下无线光通信技术是支持对海洋资源的信息探测、采集与传输的关键技术之一，它克服了水下有缆通信对通信实体活动范围的限制，以及传统水声通信技术存在的带宽小、传输速率低、时延大等缺点，可支持水下设备节点之间的动态、高速通信。掌握水下无线光通信的核心技术，在实现海洋资源探测、环境污染监测、海底火山与地震测量、航海安全、国防军事应用等方面有着重要的现实意义，是实施国家“南海战略”的关键技术支撑之一。目前水下无线光通信技术仍处于初期发展阶段，水下设备的信息传输仍远达不到陆地无线通信系统的高容量与高可靠性。本项目在水下无线光通信系统的信道容量分析与编码技术研究、水下光信道估计与信号检测技术研究、水下无线光通信系统的功率峰均比降低技术研究、水下无线光通信系统原型研究及性能验证等方面开展了工作，取得了较好的成果，包括：提出了基于分组马尔科夫叠加编码、LDPC码、RS码的多种新型信道编解码方案，以及将编码与不同调制方式有机结合的创新混合方案，有效提升了系统的可靠性；提出了一系列的水下光信道估计与信号检测方案，对实际水下场景的多种非理想因素进行了匹配的设计，有效拓展了水下无线光通信系统的实际应用范畴；提出了针对OFDM系统的多种功率峰均比抑制方案，在降低或维持误码率水平的情况下实现了对PAPR的有效削减，这为水下设备节省宝贵的资源和成本提供了重要的设计参考；搭建了水下无线光通信系统原型，对部分自研算法进行了测试，通过实验验证了算法在真实水下信道环境中应用的可行性和性能的优越性。本项目的理论研究成果将有助于推动本领域的源头创新和知识积累，相关发明专利和系统原型将有望在未来通过成果转化实现产学研用结合的目标，助力我国电子信息产业的技术升级，提升我国在该领域的国际竞争力。