Development of a Shielding Box for Through-Facade Coupler (TFC) Evaluation

Inhalt:
In this paper we present a tailoredaluminium shielding box for the evaluation of “through-facade couplers (TFCs)”, which are developed by us within another activity. The box shall mimic the damping of electromagnetic waves, coming from outside base stations, caused by facades. First, the original aluminium box is characterized in a broadband manner based on its shielding effectiveness. In order to improve its performance, foam absorbers and the shielding strips have been mounted to the inside and along the door of the aluminium box, respectively. The absorbers reduce the standing waves inside the small box and mimic therefore the wanted indoor environment in a better manner.The indoor signal is measured via different field probes and antenna, to achieve a robust characterisation. An isolation of better than 40 dB has been measured over a broad range of frequencies (1 GHz – 5 GHz). Thus, the developed shielding box can replace a typical building for the desired mobile and compact TFC evaluation.