A simple method for estimating radiated emissions
17 May 2021
A simple method for estimating radiated emissions
I recently received the following question:
How to calculate the radiated E field with following test conditions with an antenna placed 1 meter away from the test setup?:
- A commercial equipment under test with metal housing
- Equipment placed on the grounded metallic table/plane
- LISN installed (and also placed on mentioned metallic ground plane)
- Cable length between LISN and equipment under test = 1.5 m (so length > lambda/4 i.e. 1.5 m > 1 meter so cable is electrically long)
- Cable height above ground plane = 5 cm
- Frequency of interest/measurement = 75 MHz
What will be the equation to find the radiated E field with high degree of confidence?
Please open the pdf to see my reply
Photo by Emily Morter on Unsplash
Some useful references are below:-
- https://www.emcstandards.co.uk/close-field-testing-for-every-project-stage
- https://www.emcstandards.co.uk/diy-emc-testing-series-2001
- https://www.emcstandards.co.uk/estimating-the-overall-emissions-of-combined-it
- https://www.emcstandards.co.uk/emc-testing
- https://www.emcstandards.co.uk/complying-with-the-emc-directive1
- https://www.emcstandards.co.uk/additional-resources
You may be interested to know that I am providing some on-demand training in May 2021 on the following subjects:-
- Why “CE+CE=CE” cannot be relied upon for EMC compliance
- Low-cost, quick, benchtop EMC testing helps de-risk all project stages
- How to achieve EMC Compliance under the RED
- Practical Electronic Design Techniques for Cost-Effective SI, PI and EMC in 2021
Please visit EMCUK to register!
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