毫米波接收机前端研究

【作者】 赵涔伶；

【导师】 羊恺；

【作者基本信息】 电子科技大学 ， 电路与系统， 2010， 硕士

【摘要】 由于微波频谱的日益拥挤,以及红外和光系统在恶劣环境和夜间工作的局限,加快了对毫米波的研究和应用。此外,毫米波本身所固有的特点也促进了毫米波系统在军事和民用领域的发展。毫米波接收技术也随之快速发展。本论文研究了毫米波频段接收机前端子系统。该接收机前端子系统采用固定本振的超外差结构,其射频输入信号频率范围35.3-36.5GHz,本振频率34GHz。其中接收链路由低噪声放大器、射频前端预选滤波器、混频器、中频放大器和中频放大器组成,本振链路由倍频器、放大器和滤波器组成。论文仔细地分析了毫米波接收机前端系统的设计方案,根据系统的设计目标阐述了该毫米波前端子系统的指标分配。重点分析了滤波器、低噪声放大器以及混频器等电路的工作原理和设计方法。结合各器件的具体指标要求给出了各独立器件详细设计过程。对制作的接收机前端子系统进行了系统的测试,取得了良好的测试结果。该接收机前端系统的噪声系数小于3.4dB,增益优于17.6dB,镜像抑制度大于40dB。最后,针对系统不足之处进行了综合深入的分析并提出改进意见。特别讨论了用基片集成波导滤波器替代波导滤波器,来作为系统射频前端预选滤波器的小型化改进方案。更多还原

【Abstract】 The exploitation of millimeter wave is promoted by both the increasingly congested microwave spectral region and the limitations of infrared and optical systems when working under harsh environment and night time. On the other side, because of characteristics of millimeter wave, it has established itself in a wide range of military and civil practical applications. The millimeter-wave receiving technique has acquired considerable progress.The dissertation researches a millimeter-wave receiver front-end subsystem. This subsystem uses the superheterodyne architecture of a fixed local oscillator. The frequency range of RF input signal is 35.3-36.5GHz and the LO frequency is 34GHz. The receiving link of the subsystem is composed by a low-noise amplifier, RF front-end pre-filter, mixer, IF filter and IF amplifier. The local oscillator chain is composed by the frequency multiplier, amplifier and filter.The design of millimeter-wave receiver front-end system is carefully analyzed. according to the design goals of system, The indicators’assigning of millimetre-wave receiver front-end subsystem is described. Then the dissertion focuses on the analysis of the working principle and engineering design methods of filter and solid-state circuitry including low-noise amplifier and mixer, etc. Combining with the specific requirements of this design , it also gives the design process of the independent device.The receiver front-end subsystem has been tested. The testing results: noise figure is less than 3.4dB, gain is better than 17.6dB, image rejection is greater than 40dB. Finally, aiming at the inadequacies of the system, a plan of design is proposed. As a RF front-end pre-filter, a small inprovements program which replace waveguide filters by substrate integrated waveguide filter is dicussed.更多还原