卫星超宽带通信理论与技术

Theory and technology of ultra wide band is one of the key technologies in high transmitting rate and concealing communications of satellite to ground station and that of inter satellites links. On the deeply study on abroad advanced ultra wide bandwidth modulation methods, the project will solve propagation characteristics and channel model of the link between satellite and ground station and channel model of inter satellites link, interference between UWB system and other communications system, technologies of ultra wide bandwidth pulse waveform design, selection of pulse modulation mode, and pulse ranging, which are suitable for satellites of our country. The project will construct communications and telemetry downlink from satellite to ground station architecture that based on pulse modulation, and simultaneous architecture of data transmission, tele-command, telemetry, precision ranging. This project will propose modulation scheme for high effective communication, tele- command, telemetry and ranging, set up simulation experiment system, analyse kinds of factors which effect system performance, and put forward optimized solution finally. The project will achieve the basic work in extending channel capacity,acquiring high channel gain and compressing frequency source for satellite communications, enhance our nation's space technical innovation ability of satellites anti-intercept, anti-spy, and that of high speed communications from satellite to ground station, and inter satellite links, realize technology span.

超宽带理论与技术是实现卫星到地面站、以及卫星星间链路无线高速隐蔽通信的核心技术问题。本项目在深入研究国外先进的超宽带信号调制方法的基础上，解决适用于我国卫星与地面站、卫星星间链路高速隐蔽通信所涉及的超宽带脉冲信号在星地链路和星间链路信道的传播特性和信道模型、UWB系统与其他通信系统之间的相互干扰分析、超宽带脉冲形状设计技术、脉冲调制方式的选择、以及脉冲测距技术，设计基于超宽带脉冲的卫星与地面站的下行通信和遥测方案、卫星星间链路同时进行数据传输、遥控、遥测与精密测距的方案，提出能够同时进行高效通信、测控和测距的通信体制。建立仿真实验系统，解析影响系统性能的各种因素，并提出相应地解决措施，优化所提出的实施方案。本项目的研究成果将为我国在卫星数据传输和测控的大容量、高信道增益、节省频率资源方面奠定关键技术基础，增强我国卫星抗截获抗侦查和高速星地及星间通信的创新能力，实现我国空间技术跨越式发展。

本项目首先列举和使用MATLAB软件仿真了多种脉冲型信号，对各种脉冲信号的时域特性和频域特性进行了比较；其次完成了两种工作于毫米波频段的超宽带脉冲天线的设计。结合卫星高速、大容量通信与隐蔽、强抗干扰测控的相关需求，以及未来星地高可靠测控需求，研究了基于多载波超宽带（MB-OFDM-UWB）的通信技术。开展了超宽带星地通信总体方案设计，针对关键技术进行了仿真验证，设计与实现了原理样机，并进行了通信效能测试验证。实测误码率低于10E-6，验证了MB-OFDM-UWB体制在复杂多径环境下的传输能力。UWB 技术在卫星通信系统中具有巨大的发展空间和广泛的应用前景，该研究工作的成果可为解决卫星通信频率资源日益匮乏的现状提供关键技术支撑和实现途径。