I used an RF shielding product which claims 80 dB attenuation at 2.4 GHz. Why am I only seeing 20 dB?
There is only one important 1 key to successful RF shielding: control leakage. Remember that the attenuation spec for a shielding material is how much radiation penetrates through the shield. Lets look at an analogy: In many ways, RF behaves much like visible light, and RF shielding materials behave much like two sided mirrors. Image that you are outdoors on a sunny day. You set a large mirror on a stand above your head. The attenuation specification for the mirror is very high, perhaps 120 dB or more, so basically no light comes through the mirror. If leakage was not an issue, you would be in total darkness. We all know this is not the case. Leakage from the sides easily illuminates the shaded area. Granted, the amount of illumination is less than standing in full sunlight, but the attenuation is no where near 120 dB. Maybe more like 20 dB. Furthermore, using a shield with even better attenuation will not yield any more benefit. Now imagine you are in a small room with only one window
