Errors of antenna factor and improved method for NSA test
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摘要: 总结了归一化场地衰减(NSA,The Normalized Site Attenuation)测试中存在的误差,指出误差主要来源于天线系数.通过对天线互阻抗的分析,说明它是天线系数误差的主要来源.简单介绍了天线系数的标准计量方法,发现其中并未考虑互阻抗的影响;修正了天线系数计量中采用的方程组,证明该方程组不能求解.分析了减小测试天线间互阻抗误差的因素,重新设计了一种新的测试方法.新方法使用天线增益替代天线系数,利用天线增益测试的必要条件避免互阻抗的影响;证明了新方法与原方法的原理间的等价条件;通过实测验证了新方法的有效性.Abstract: The normalized site attenuation (NSA) was studied during the test process. The measurement errors were mainly brought by the antenna factor, with the mutual impedance analysis. The standard method of measuring antenna factors was introduced and the mutual impedance effect was found to be neglected. The equations of traditional method were proved to be no solution. The conditions were analyzed to decrease the errors of the mutual impedance between antennas. The antenna factor was replaced by the antenna gain, and the mutual impedance effect can be avoided in the antenna gain measurement. The equivalent conditions were proved between the new method and the original method. The validity of the new method was proved by the real test results.
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Key words:
- electromagnetic compatibility /
- errors /
- antennas
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