太赫兹频段超宽带数字边带分离接收机关键技术研究

Terahertz band is essential for research on formation and evolution of galaxies, matter recycling among stars and interstellar medium, planets origination, the physical and chemical characteristics of the atmosphere as well as the origin of life in the universe..One of the main goals of terahertz astronomical observation is to obtain information of the celestial molecular rotation spectrum and the atomic fine structure spectrum. These spectra contain various physical and chemical properties of celestial bodies during their origin and evolution. The wider the bandwidth, the greater the amount of information contained; the higher the spectral resolution, the richer the information content revealed..Due to the increasing demands for bandwidth and overall performance of THz astronomical observation equipment，we plan to conduct research on key technologies of ultra-wideband digital sideband-separating receiver at terahertz band, including research on fundamental principles of ultra-wideband digital sideband-separating receiving system, numerical simulation methods of digital sideband-separating spectrum processing and sideband imbalance calibration, and the characterization method of overall system performance and signal detection experiment. .This project will break through the key technologies of ultra-wideband digital sideband-separating receiving, and lay a solid technical foundation for improving the performances of the next generation facilities, which can be equipped on radio, millimeter and terahertz astronomy telescopes and so on. .The ultra-wideband digital sideband-separating receiving technologies involved in this project have wide application prospects, which can also be used in other fields such as Earth's atmospheric sciences, terahertz communications, and national related aspects etc.

太赫兹波段是研究星系形成和演化、恒星与星系介质间物质循环、行星起源以及大气物理化学特性及宇宙生命起源的重要波段。太赫兹天文观测的核心内容之一是获取天体分子转动谱线和原子精细结构谱线等信息，这些频谱承载了包含天体起源和演化等各种物理化学过程的主要信息。带宽越宽，包含的信息量越大；谱分辨本领越高，信息的内容越丰富。针对太赫兹天文观测设备带宽和总体性能不断提升需求，本申请开展太赫兹频段超宽带数字边带分离接收机关键技术研究，主要包括系统原理解明、数字边带分离频谱处理和边带非平衡性校准数值仿真方法研究、系统性能表征方法与信号检测实验研究。本申请项目研究将突破超宽带数字边带分离接收机关键技术，为我国射电、毫米波、太赫兹望远镜等下一代主力观测设备性能提升，打下坚实的技术基础。超宽带数字边带分离接收技术在地球大气科学、太赫兹通讯以及国家需求等具有广泛的应景。

本项目开展太赫兹频段超宽带数字边带分离接收机关键技术研究，主要包括系统原理解明、数字边带分离频谱处理和边带非平衡性校准数值仿真方法研究、系统性能表征方法与信号检测实验研究。本项目取得的主要研究进展包括：1) 完成了太赫兹频段数字边带分离接收系关键技术包括太赫兹频段数字边带分离、数字边带分离非平衡性校准、实时FFT频谱处理等技术研究。2) 完成了数字边带分离理论分析、数字边带非平衡性校准数值仿真，以及基于Simulink的数字边带分离校准算法的硬件仿真，为开展研制数字边带分离校准频谱仪系统奠定基础。3）完成了3~18GHz频段数字边带分离接收机原系统构建，完成了基于该原理系统的边带非平衡性校准和边带抑制比测试实验。4) 完成了数字边带分离校准实时FFT频谱仪研制及频谱仪主要性能指标的实验表征。