弱太阳闪烁对深空电波散射特性分析及信道建模研究

The problem of scattering caused by the coronal solar wind irregularities on the radio wave propagation during superior solar conjunction has become an urgent issue that needs to be solved in the future deep space communications. Aiming at exploring the fundamental theories, mechanisms and key technical innovations involved in the radio wave propagation through the coronal plasma, this project focuses on studying the scattering characteristics and channel characteristics of the radio wave. The main works are as followings: ① The mechanism of the scattering effect caused by solar wind plasma on the radio wave propagation in deep space is analyzed first. We mainly focus on the impact of the random distribution of the solar wind plasma on the radio wave scattering. ② A new scattering prediction model based on Markov approximation theory and extend Rytov approximation theory is proposed, which can be used when the radio wave propagates through the anisotropic and magnetized solar wind turbulence under the weak scintillation. ③ With these developed scattering characteristics of the radio wave, the coronal channel model is proposed and its impact on the deep space communication has been evaluated combining with the background model of the coronal. This project will be of great significance for revealing the scattering properties of the radio wave in the solar wind and the coronal channels characteristics. The research achievements will provide an advance theoretical support for the study of satellite communications in future deep space exploration.

深空无线电波在上合期间受日冕区太阳风湍涡不规则性影响所引起的散射问题已成为未来深空通信亟需解决的难题。项目将开展无线电波在日冕区太阳风中传播时散射特性和信道特性的研究，旨在探究日冕区无线电波散射和日冕区信道特性所涉及到基础理论、机理和关键技术上的创新。研究内容包括：①太阳风等离子体对深空电波传播散射特性影响机理的研究，重点研究太阳风等离子体随机分布对电波散射特性的影响规律。②基于Markov近似理论、扩展的Rytov近似理论和FDTD改进算法，研究无线电波穿过各向异性磁化太阳风湍涡时电磁散射特性的理论模型，拓展弱太阳闪烁下电波闪烁指数的预测模型。③基于电波散射特性的研究建立日冕信道模型，结合日冕区背景模型完成弱太阳闪烁对深空通信信道质量影响的评估。本项目的研究对于揭示日冕区电波传播的散射特性以及日冕信道特性有着重要意义，项目成果有望为我国未来深空探测中星地通信的研究提供预先的理论支撑。

本项目紧密结合我国未来深空探测及深空通信的发展趋势和重大需求，针对上合期间日冕区太阳风对电波传播所造成的影响，基于等离子物理学及电磁场和电波传播理论，开展太阳风等离子体对电波传播散射特性影响的分析，揭示太阳风对深空通信中电波传播的影响机理。此外，考虑各向异性太阳风湍涡下电波散射特性的数值计算方法，建立电波在磁化太阳风等离子体内电磁散射特性的理论模型，突破传统计算理论难以求解各向异性湍涡下的弱太阳闪烁问题，有效解决传统近似算法计算精度低、内存消耗大、无法适用于具有随机特性太阳风等离子体中的计算问题。在此基础上，对深空信道传输特性进行研究，建立太阳闪烁下深空电波传播的通信信道模型，揭示太阳风等离子体密度随机特性对信号传输质量的影响规律，并评估日冕环境参数对信道质量的影响。项目的研究内容为我国未来深空探测链路通信能力的提升提供基础理论和关键技术支撑。.项目执行期间，共发表学术论文17篇，其中SCI检索的期刊论文16篇，EI检索会议论文1篇，标注率100%；申请国家发明专利2项，申请软件著作权2件。参与申请国家自然科学基金重大科研仪器项目1项、重点项目1项。完成搭建面向深空探测的空间环境数据库模型的软件仿真平台。承办国内学术会议2次，聘请国内外知名专家做学术报告15人次，此外，累计参加校外相关领域学术会议10余次，并做大会报告4次。