文档介绍：基站天线测量方法
Test specification of Base station antenna center
1 增益、半功率波束宽度、前后比及交叉极化比的测量可以采用远场或近场等测试方法,本标准叙述最常用的远场测试方法。
The test has long distance and near distance for antenna gain,beam width front to back ratio amd polarization.
2 增益测量 Gain test
test draws:
Source antenna
源天线 The antenna 信号源发生器隔离器
图1天线增益测试框图 antenna gain testing draws 测量条件 test qualification
。
The antenna and source antenna is same polarization
:
2(D2+d2) ……………………………….(1) L ≧λ
式中:L──源天线与被测天线距离m; there is distance of the antenna to source antenna D──被测天线最尺寸m; there is max dimension of source antenna
D──源天线最大辐射尺寸m; there is max radiancy of the antenna
λ──测试频率波长m。 test frequency beam long
,场强应预先用一个半波偶极天线的有效天线体积内进行检测,,则认为试验场是不可用的。此外,增益基准天线在两个正交极化面上测得的场强差值小于1dB。
The antenna under test should be placed within a constant field,and the field stremgth can first be measured within the ism field of the antenna under test. Should the electric field show fluctuations greater than , the test field should ge considered unsuitable. Moreover, the measured field stremgrhs of the horizontal amd vertical ponents, s measured by the standard gain antenna, should mot differ by more than 1dB.
、接收机等测量设备和仪表应具有良好的稳定性、可靠性、动态范围和测量精度,以保证测量数据的正确性。测量用仪表应有计量合格证,并在校验周期内。 The signal generator,receiver and other equipment and meters used for testing should have high stability, reliability,measurement precision and wide dynamic range in order to guarantee data accuracy.

开始测量时,必须将被测天线和增益基准天线交替做水平和俯仰调整,以确保每一天线在水平和俯仰上的最佳指向,使其接收的功率电平为最大。
When beginning a measurement, it is importantto first perform azimuth and elevation adjustments on both thestandard gain antenna and the antenna under test, to ensure each day the same optimum azimuth and elevatin are
used and maximum power is attained.
测量步骤如下:
A. 增益基准天线与源天线对准,通过转接,使增益基准天线与接收机相连接,此时接收机接收功率为P1(dBm)﹔enchmark antenna and source antenna