小型化频谱监测设备前端组件的设计与实现

发布时间：2018-05-22 07:13

本文选题：频谱监测 + 射频　；参考：《电子科技大学》2014年硕士论文

【摘要】：随着通讯事业的快速发展,通信设备的种类和数量急速增长,导致可供分配的频谱资源越来稀缺。频谱拥挤和频段的非法占用日益成为影响无线通信的重大因素,无线电监管部门正面临着越来越复杂和严峻的频谱监测和管理问题。无线电频谱监测是频谱监管的主要环节,频谱监测成为未来频率分配规划、无线发射技术特性测量、无线信号发射源查寻等领域必不可少的手段。本论文根据项目需求,设计一款监测频谱范围覆盖9kHz~8GHz,实时分析带宽10MHz的高性能、高灵敏度、小型化、低功耗的频谱监测设备前端组件,此监测设备同时具备频谱监测和数字调制信号分析等功能。本文采取目前常用的超外差接收机架构,摒弃台式监测设备前端组件采用的开关滤波器组或YIG可调滤波器做预选滤波的实现方案,采用第一中频频率为9.864GHz的高中频的变频方案实现。待测射频信号经过一次上变频和两次下变频之后,降频到ADC可处理的中心频率为64MHz,带宽10MHz的中频信号,并通过滤波和信号调理等手段将变频过程中引入的杂散信号滤除,保证监测设备的高灵敏度、大动态范围等指标要求。本文首先提出了监测设备射频前端的设计指标,并对噪声系数、灵敏度、P1dB功率压缩点、杂散响应、剩余响应等关键指标进行分析,指出这些关键指标对监测设备系统的影响并提出影响指标的各项因素。其次对监测设备射频前端进行系统级设计,包括系统架构选择、变频方案设计、杂散分析、链路增益分配和噪声分析等,并运用ADS软件做系统级仿真分析,提出一种可行的监测设备射频前端系统方案。然后对监测设备射频前端系统进行模块化分解,完成程控衰减器单元、前置低噪声放大器单元、三级变频单元等单元电路的设计、实现和测试工作。其中变频单元分为前置镜像滤波器电路、混频电路、中频滤波器电路和中频信号调理电路等部分,滤波器采用微带滤波器、声表面滤波器和LC滤波器等小型化设计方案,信号调理电路采取低功耗方案设计。最后将各单元电路集成为监测设备的射频前端系统,对系统各项指标用标准测试方案进行测试并进行结果分析。
[Abstract]:With the rapid development of communication industry, the types and quantity of communication equipment are increasing rapidly, which leads to the scarcity of spectrum resources available for allocation. Spectrum congestion and illegal occupation of frequency band are increasingly becoming a major factor affecting wireless communication. Radio regulatory authorities are facing more and more complex and severe spectrum monitoring and management problems. Radio spectrum monitoring is the main link of spectrum monitoring. Spectrum monitoring has become an indispensable means in the future frequency distribution planning, wireless transmission technology characteristics measurement, wireless signal emission source search and other fields. According to the requirements of the project, this paper designs a front-end component of the spectrum monitoring equipment which covers 9kHz, 8GHz, real-time analysis bandwidth 10MHz with high performance, high sensitivity, miniaturization and low power consumption. The monitoring equipment has the functions of spectrum monitoring and digital modulation signal analysis. In this paper, the current superheterodyne receiver architecture is adopted, and the implementation scheme of switching filter bank or YIG tunable filter used in front-end component of desktop monitoring equipment as pre-selected filter is abandoned. The first intermediate frequency is 9.864GHz and the high frequency conversion scheme is adopted. After one up-conversion and two downconversion, the RF signal to be tested can be reduced to the center frequency of 64MHz, the intermediate frequency signal of the bandwidth 10MHz is reduced to the center frequency, and the stray signal introduced in the frequency conversion process is filtered by filtering and signal conditioning, etc. Ensure high sensitivity and wide dynamic range of monitoring equipment. In this paper, the design index of RF front-end of monitoring equipment is put forward, and the key indexes, such as noise coefficient, sensitivity of P1dB power compression point, stray response and residual response, are analyzed. The influence of these key indexes on the monitoring equipment system is pointed out and the factors affecting the indicators are put forward. Secondly, the RF front-end of monitoring equipment is designed at system level, including system architecture selection, frequency conversion scheme design, stray analysis, link gain allocation and noise analysis, and system level simulation analysis is done by using ADS software. A feasible RF front end system for monitoring equipment is proposed. Then the module decomposition of the RF front-end system of the monitoring equipment is carried out to complete the design, implementation and testing of the programmable attenuator unit, the preposition low noise amplifier unit, the three-stage frequency conversion unit and so on. The frequency conversion unit is divided into three parts: premirror filter circuit, mixing circuit, intermediate frequency filter circuit and if signal conditioning circuit. The filter adopts miniaturized design schemes such as microstrip filter, acoustic surface filter and LC filter. The signal conditioning circuit is designed with low power consumption. Finally, the unit circuits are integrated into the RF front-end system of the monitoring equipment, and the system indexes are tested by the standard test scheme and the results are analyzed.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM935.21

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