Engineers' Guide to Pre-compliance Radiated Emission Test
HTML-код
- Опубликовано: 26 май 2024
- Design engineers often need to perform multiple design iterations before finalising the product. How do we ensure the radiated emission of the product is below the limit line before we send the unit for compliance tests (in an anechoic chamber)? This is the ultimate guide to pre-compliance radiated emission tests.
CHAPTERS
00:00 Chapter 1 Introduction
02:38 Chapter 2 TEM Cell Measurement Set-up
07:36 Chapter 3 TEM Cell Measurement using EMCView
14:18 Chapter 4 Far Field Measurement Set-up
18:28 Chapter 5 Antenna Factor
22:30 Chapter 6 EMCView Set-up
26:00 Chapter 7 Scanning
27:27 Chapter 8 Combined TEM Cell and Antenna Results
32:25 Chapter 9 Testing DUT at 1-meter Distance
35:48 Chapter 10 Using a Small Antenna with TEM Cell
38:30 Chapter 11 Results - Pass or Fail?
42:35 Chapter 12 QP scan
43:35 Chapter 13 Cable Radiation using an RF Current Probe
Thank you for making the video and sharing your knowledge with us. Much appreciated.
Agreed, thank you for taking the time. We can appreciate how long a detailed video, with Brad Pitt acting, can take!
Thanks for the video. I wonder what SA you are using in open field. Looks quite slim and portable.
Very nice video Min! A time ago I noticed a LinkedIn post about a new course; is it already published? 😃
Not Yet, Remy, still working on it in my spare time. Will let you know as soon as i get one.
Hi Min, awesome video. You are saying at some point that the real time spectrum analyzer is making the scan in EMCview faster. How much slower would it be on a non real time one (e.g. : Siglent SSA3021X Plus) ?
Hi Alexandre, I think we are talking about less than a minute to do a full sweep to 1GHz with the real time SA, with the sweep type SA, it takes 5-6 minutes to do a full sweep, I haven't tested it properly, but it is close enough. Hope this helps
Did you ever test it, when we sweep the Real time vs the standard unit we found it half as fast.
Min how often does being near metal and having other EMI signals in your environment, say in an office, ever make the measured results less than they should be? I can imagine there may be destructive interference but would not in almost all cases the interference be constructive? Would that not mean that if you can pass the CISPR standard in your office, you should be able to pass it in the chamber?
I am aware that one major concern is you may waste time attempting to reduce phantom signals when your device is not the cause but excluding that fact maybe office results can be considered a conservative estimate of chamber results, right?
Very good question Abdifatah, as you said, in order to ensure the noise is generated by the DUT, not something else, we need to do some preparation, TEMCELL, near field probe and even checking the design datasheet, as shown in the video.
Hi Min when your EMI EMC for switching mode power supply coming?
Still working on it, as I am quite busy, so can only do it in weekend or so. Need some push. lol
Hi Min,
How can you perform a radiated test without doing it in a shielded room? I assume everything would be generating some for of radiation. Would you need to then first put your EUT in a GTEM or TEM cell first to see what emissions are actually from your device?
Hi, yes, indeed, as explained in the video, because that is the only way to distinguish the noise from ambient noise. Hope this helps.
Also check incompliancemag.com/article/in-situ-radiated-emission-testing-of-large-systems-installations/