Shielding Effectiveness Experimental and Performance Analysis of Hybrid Shielding Structures for Building Walls

Qi Tai 110m radio Telescope (QTT) is a fully steerable single-dish radio telescope with an observing frequency coverage from 150 MHz to 115 GHz. The QTT will play an important role for fundamental research fields of radio astronomy, such as pulsars, molecular spectral lines, active galactic nuclei, and VLBI observations [1]–[2]. In response to the EMI (Electromagnetic Interference) coming from electronic equipment in buildings, we would like to shield the whole buildings with a hybrid shielding structure combining building walls and mesh layers. To verify the performance of the shielding structures, we conducted on three types of shielding walls (red brick, porous brick, and bubble brick) experiment and SE (Shielding Effectiveness) measurements. The testing results indicate that the SE of all three types of shielding walls can achieve 55 dB in 0.1-1GHz and 45 dB over 1 to 18 GHz respectively, which show that the performance of the hybrid shielding structure is perfect that can be employed in the buildings.