Anechoic Chambers
Shielded Chambers,
Screened Rooms
& Faraday Cages
Anechoic Absorbers
Shielding materials & shielding components

The facts about Building shielding

Building shielding
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An unbiased data sheet


Building shielding can be achieved by foil, conductive fabric or modular steel panels. For a faraday cage to work there has to be an unbroken electrically conductive surface around all walls, ceiling, floor and edges, any other intrusions or brakes in the conductive surface have to be properly engineered


According to the rules of Faraday cage engineering:


  1. All conductive intrusions going into or out of the chamber need to be a part of the shield conductive surface, in consideration of this the water pipes, heating ducts etc need special consideration.
  2. The aesthetics (looks) are much better
  3. It gives more space and this is important in small anechoic chambers.

The principal of pyramidal absorbers are to prevent reflections by ‘progressive impedance’ this is normally done by the progressive shape of the pyramid and the resistive material that the absorber is made of.


When the absorber is truncated the shape is no longer progressive and so in higher frequencies where the wave becomes small then the truncated face of the absorber will inhibit (ruin) the performance of this absorber type.


In terms of maximum achievable performance (return loss) the truncated absorbers should be considered for sub-microwave <1GHz, although, they will work but at only at a reduced performance level.


Hybrid truncated pyramidal absorber

Hybrid absorbers are designed to work in conjunction with ferrite tiles and so have far less carbon doping.


The effect of truncating there very lightly doped absorbers is far less than the effect with fully doped absorbers.