Anechoic Chamber Reliability

Hello

How can we test how effective an anechoic chamber is at suppressions reflections?

normally, during the construction of an anechoic chamber several tests are performed to check if the structure is well-building up. Those tests are performed by someone who is accreditated to do the tests and releases the certification for each one.

Typically, a well-known antenna pattern measurement can be indicative of how the chamber works. If the results is what you expected you can suppose that the chamber does its work. Anyway this is a simple, cost-less and trivial way to get only an idea of the absence of reflections by side wall.

But, if I wanted to test the chamber I would measure the reflection from sidewalls by using only 1 tx/rx antenna, locating it in the middle of the chamber. I would measure S11 in the chamber and compare it with the calculated expression I would expect in the free space. By comparing them I would probably get an indication about the reflections from boundaries....

thanks beetro78, I have a better idea now.

I have had another thought...Is there any way to test the absorbing material?

Yes, but I'm not an expert in the topic. Anyway, by placing an absorber wall (one pannel can be enough at high frequency) in the front of a bundle system of two antennas, one trasmittig and one receiving, you can carachterize the behaviour of the pannel.

At low frequency it can be difficult since you need electrically large structure to reduce the scattering boudaries effects.

Anyway, I'm sure that there is a lot of litterature you can find on anechoic chamber testing, shield testing, absorber testing, etc...I would look up on Amazon
Bye