EMI 1G以上的测试问题

zhangjuan008

  EMI1G以上是在全电波暗室还是半电波暗室？天线高度分别是多少？


以下是R&S的回复：
For testing above 1GHz, a fully anaechoic chamber is required. At your site, you will need to lay the absorbers between the EUT and the receive antenna.

In a fully anechoic chamber, the measurement antenna do not need to be tested from 1m to 4m as long as the antenna beamwidth covers the EUT volume.

If you are testing a small EUT like mobile phone, you do not need to move the antenna. The cable I provided is for fixed height a 1m, as required by your EUT.


For other EUT that has a large volume, you will need to move the antenna to the next height that was not measured in the previous measurement, or not covered by the beamwidth. So in a sense it is different from RE below 1GHz. The summary is as follows,

Summary
RE < 1GHz        move the antenna 1m to 4m to search for highest emission, can be from reflection from the ground plane.
RE > 1GHz        measure at a fixed height. check that the beamwidth covers the EUT, else move to another height to measure the next beamwidth position. not limited to 4m, but depending on the EUT volume.

zhjiang2009

天线分别在1，2，3，4m处。全波

wzy1011

1GHz以上,antenna不需要升到4m,以EUT包含的範圍頂端為天線最高量測高度即可.但是FCC-OET對於1GHz測試方式要求不同於CISPR, 必須從1-4m量測,並且需確保antenna的3dB beamwidth在整個量測過程中能對準EUT的訊號源,對於測試場地則無特別要求。