基于空间型光控太赫兹调制器的通信及成像系统

发布时间：2018-05-08 21:47

本文选题：太赫兹 + 太赫兹通信　；参考：《电子科技大学》2017年硕士论文

【摘要】：近年来被誉为“世纪前沿革命”的太赫兹技术成为热门科研课题。其中太赫兹通信及太赫兹成像是太赫兹技术研究和应用方面的重中之重。太赫兹波的频率高于现阶段微波通信中的载波频率,随着人们对无线通信带宽需求的成倍增长,太赫兹通信必将成为未来高速短距离无线通信和外层空间通信中的重点研究课题。利用太赫兹波特有的性质,太赫兹成像技术在环境监测、医疗诊断、无损探伤、安全检测和军用雷达等方面有着广阔的应用前景。现阶段,太赫兹通信主要是基于现有的微波通信技术在微波段进行信号处理,再倍频至太赫兹频段产生调制信号。或者直接调控太赫兹源产生振幅、相位、频率可控的太赫兹波进行调制。太赫兹成像主要是基于相干成像技术,如太赫兹时域光谱成像。本文基于空间型太赫兹光控调制器研究了一套太赫兹通信及成像系统。与上述通信及成像方式有不同之处,该系统能够在空间中直接对太赫兹波进行调制从而实现空间直接调制方式的太赫兹通信以及相干太赫兹连续波成像。首先,本文研究了一种基于硅纳米针结构的空间直接调制光控太赫兹幅度调制器。发现该微纳结构对太赫兹波相较于半导体硅有明显的增透作用,可以大大降低太赫兹插入损耗。测得其透射率可以达到85%甚至更高。对黑硅进行研究,制备了调制深度超过80%,静态下可“关断”的,空间直接调制太赫兹调制器。接着,在太赫兹通信方面。本文采用LaVIEW编程控制数据采集卡的方法,实现了信号的A/D转换以及通信过程中基抗干扰能力。为了实带信号的产生和接收。通信时,运用了2ASK调制解调方案,并进行了编码与解码以提升现语音实时通信,扩展了语音自动采集、自动传输、自动播放程序。另外,在太赫兹成像研究中,本文基于太赫兹通信系统做出相应调整,搭建了一套太赫兹连续波单像素成像系统。在空间光调制器的基础上提出了一种基于黑硅的空间型太赫兹光控幅度调制器,对太赫兹波的空间分布进行调控,实现了太赫兹非机械式单像素扫描,获得了太赫兹空间分布强度信息。并用Matlab将太赫兹强度信息转换为图像实现成像。最后,本文通过共用设备和仪器搭建了一套能同时实现太赫兹通信与成像功能的系统。通过传输文字、图片、语音信号对该系统的通信功能进行了验证,并且成功进行了太赫兹成像实验。
[Abstract]:In recent years, terahertz technology, known as the "frontier revolution of the century", has become a hot research topic. Terahertz communication and terahertz imaging are the most important in the research and application of terahertz technology. The frequency of terahertz wave is higher than the carrier frequency of microwave communication at the present stage. As the demand for wireless communication bandwidth increases exponentially, Terahertz communication will become an important research topic in future high-speed and short-range wireless communication and outer space communication. Using the properties of terahertz Potter, terahertz imaging technology has a broad application prospect in environmental monitoring, medical diagnosis, nondestructive testing, safety detection and military radar. At present, terahertz communication is mainly based on the existing microwave communication technology to process the signal in the microwave band, and the modulation signal is generated from the frequency doubling to the terahertz band. Or directly adjust the terahertz source to generate amplitude, phase, and frequency controllable terahertz wave modulation. Terahertz imaging is mainly based on coherent imaging techniques, such as terahertz time domain spectroscopy imaging. In this paper, a terahertz communication and imaging system is studied based on space terahertz optical modulator. The system can modulate terahertz wave directly in space so as to realize terahertz communication and coherent terahertz continuous wave imaging. Firstly, a novel optical direct modulation terahertz amplitude modulator based on silicon nanoscale structure is studied. It is found that the micro- and nanocrystalline structure has obvious antireflection effect on terahertz wave compared with semiconductor silicon and can greatly reduce the insertion loss of terahertz. The transmittance can reach 85% or higher. A terahertz modulator with modulation depth over 80, which can be "turned off" in static state, has been fabricated by the study of black silicon. Then, in terms of terahertz communications. In this paper, the method of controlling data acquisition card with LaVIEW programming is used to realize the A- / D conversion of the signal and the ability of anti-jamming in the communication process. For the generation and reception of real band signals. The 2ASK modulation and demodulation scheme is used in the communication, and the coding and decoding are carried out to improve the real time communication of the current voice. The program of automatic voice acquisition, automatic transmission and automatic playback is extended. In addition, in the study of terahertz imaging, a terahertz continuous wave single pixel imaging system is built based on the corresponding adjustment of terahertz communication system. Based on the spatial light modulator, a space-type terahertz photo-controlled amplitude modulator based on black silicon is proposed. The spatial distribution of terahertz wave is regulated, and the terahertz non-mechanical single-pixel scanning is realized. The intensity information of terahertz spatial distribution is obtained. The terahertz intensity information is converted to image by Matlab. Finally, a system for terahertz communication and imaging is set up by using common equipments and instruments. The communication function of the system is verified by transmitting text, picture and speech signal, and the terahertz imaging experiment is carried out successfully.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN92

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