Through Facade Coupler (TFC) for Enhancement of Indoor Wireless Communication and its Practical Evaluation with a Shielding Box

In this paper, a through facade coupler based on 0 ^th -order composite left/right-handed metamaterial antenna is presented. The coupler system consists of two antennas, the outside antenna is connected to indoor antenna through coaxial cable. Both antennas are composed of different number of unit cells to achieve a desired gain. The antennas can be tailored to install on the frame of modern window to couple 5G signals into buildings to enhance 5G communication. A shielding box is presented as a simple, practical and mobile mock-up of the EM-blocking building shell. The proposed shielding box is used to evaluate the performance of the presented coupler. The shielding box is portable and can be considered as outdoor scenario to measure the reception of 5G signal. The shielding box can provide at least 40 dB isolation for different signals. Based on the measurement results, the through facade coupler can provide 35 dB increased signal strength inside the shielding box.