Question about interferer/noise signature type
Last Post: November 6, 2020:
-
Hi Team
Are you aware of any trusted source of well-known signature of interference or noise detected in spectrum analyzers?
The reason why i am asking this, i am trying to understand what type of interference we have in UNII-3, EKAHAU says its cameras, but it sounds more like sensors to me.
Note: i have picture of the spectrum but not sure how to upload it here
-
Many years ago, you used to be able to upload pictures to this site, but they got rid of that option.
Multiple versions of the Chanalyzer software were available from Metageek the creators of the Wi-Spy spectrum analyzer (SA). They displayed a set of panels that you could compare your scans to, for identification. The panels could also help you manually decode the scans from other spectrum analyzers.
I found that in an uncluttered RF environment, or a screen room, that even a relatively inexperienced person could make a pretty reliable identification. However, in a busy location, it often took a VERY experienced person to recognize the pattern.
I just looked at the MetaGeek website and the equipment looks pretty different from what I had gotten 10 years ago.
I haven't seen a new CWNP book in years, but one of the problems the CWAP book had was that it was printed in all black and white. The Chanalyzer screens were in color, so attempting to use the book to learn Chanalyzer was almost a waste of time.
During the exam, the pictures were in color - it was very frustrating. I ended up making a fairly large notebook of nothing but SA pictures.
I passed that exam almost 9 years ago, so I guessed that study method helped.
Ekahau has been around a long time, so I would tend to believe their analysis.
-
Thanks for the details info, and the history practices there :)
Its really interesting how the telecom devices are being evolved, that interference i was talking about was really eating the UNII-3 in the whole building, while EKAHAU tried to give us the best match to camera as a source for it, it ended up these are the sources "Light sensors":
part number : JC040036 "in case the link below got hashed out"
https://www.jcc.co.uk/en_GB/docs/JCC_Lighting_-_JC040036_Datasheet_2019-10-21-105106.pdf
these sensors use Microwave at upper 5GHz UNII-3 channels.
-
Originally, based upon previous experience with devices manufactured in China, I was going to condemn this as just another piece of Chinese junk. However, based upon the specifications listed in that document, I cant blame them entirely.
Based on the voltages specified for the device, and the (oddly) stated operating frequency of 5.875 GHz, it appears that these devices were only intended for use in Europe. Where, unless things have changed Europe does NOT use the UNII-3 range. You don't say where you are located, but the FCC should definitely ban these lights in the US.
Even if it weren't out of the US, it does appear to be generating noise somewhat outside it's stated frequency range.
Totally as an aside, I don't know whether Phillips sells a compatible product, but as a Ham Radio operator I have found their lighting equipment to be SUPERIOR to all other lighting gear from an RFI perspective. They even sell MilSpec rated lights if you have a truly sensitive environment.
I hope you can come to an equitable solution to this problem.
Note that NO FCC classification is specified for the device. Specifically nothing directly mentions FCC Classes B or E. I only install FCC Class B devices.
For reference:
https://www.cableorganizer.com/images/kensington/microsaver-alarm-lock/FCC-rules.pdf
Thanks for your follow-up.
- 1