低增益GPS天线方向图的微波暗室测试方法

Pattern Test Method for Low-Gain GPS Antenna in Anechoic Chamber

低增益GPS天线测试中,受天线自身所带放大器增益的限制,其输出的信号功率无法达到后端测试设备最低输入灵敏度的要求,致使天线的方向图无法获取.针对低增益GPS天线不满足场强信号接收机接收灵敏度要求等问题,提出了低增益GPS天线方向图的微波暗室测试方法.该方法在常规GPS天线测试方法基础上增加接口转换装置,解决灵敏度不足和阻抗匹配;增加被测天线非金属支架,使天线与发射源天线高度一致;发射源天线的波束中心完全对准被测天线物理中心;增加屏蔽线焊点,以保证被测天线的馈点强度.通过实际测试验证,采用该方法可解决低增益GPS天线方向图在微波暗室的测试问题.

Because the low-gain GPS antenna does not meet the sensitivity requirement of the filed signal receiver receiving,this paper addresses a method about the low-gain GPS antenna pattern in the anechoic chamber.The method is based on the conventional GPS antenna test methods and to solve the sensitivity deficiency and the impedance matching problem by adding the interface conversion device.The added measured antenna nonmetal bracket makes antenna be the same height as the source antenna and it also results that the center of the source antenna beam can be aimed at the center of the measured antenna completely.The added shielding solder joints are used to ensure the strength of the feed point of measured antenna.The data shos that the low-gain GPS antenna pattern which is gained by this method is basically same.