Ka 波段主动成像宽带收发前端的研制

以毫米波成像应用为背景,研制了一种用于Ka波段主动成像系统的宽带收发前端。采用结构紧凑的自差式结构,降低系统成本并使其具有较高的可靠性;分析影响成像系统的动态范围和分辨率的因素,选择并设计宽频带毫米波源、低插损带通滤波器和平面缝隙天线等关键电路,使前端具有足够的输出功率和良好的杂散抑制,在31～36GHz的频带内,收发前端的输出功率大于10.4dBm,杂散抑制大于25dBc。对金属目标的成像实验结果表明,前端的方位向和距离向的分辨能力小于8cm,初步满足了主动成像的要求。

Development of a Broadband Ka band T / R Front End forActive Millimeter Wave Imaging

This paper proposed a broadband T/R front-end for active millimeter-wave imaging system.Compact self-heterodyne structure was selected in order to reduce the cost and achieve high reliability.The factors which could be having an influence on the dynamic range and resolution of imaging system were analyzed.Wide-band millimeter-wave oscillator,low insertion loss filters and planar slot antenna were implemented to fit the specifications of the system.According to the measured results,the output power was more than 10.4dBm and the sub-harmonic suppression was better than 25dBc from 31GHz to 36GHz.The metal target imaging experimental result showed that the azimuth and range resolution of the T/R front-end was less than 8cm which met the initial needs of active millimeter-wave imaging system.