Dual-Purpose Saltwater Structure: EMI Shielding Window and UHF Antenna

This paper introduces a transparent structure that serves as a dual-function device - an adjustable antenna with an electromagnetic interference (EMI) shielding window. This design achieves transparency (>91%) by using salt-water with a conductivity of 20 S/m inside regular glass, providing it to operate as an optical window. The glass structure with saltwater function as C-band EMI shielding window with shielding efficiency (SE) of more than 20 dB. To adjust the frequency and beam direction, the antenna with dual-port feeding configuration operates at UHF frequency range. The measurement outcomes indicate a bandwidth with range from 350 to 680 MHz and a radiation efficiency exceeding 60% for a basic single-port feeding distribution setup. In comparison to the basic setup, the additional configuration with two-port feeding of the same power and phase adjustment offers tunable frequency, tunable radiation, and better gain. These results highlight the flexibility of the proposed antenna, which serves as both an EMI shielding window and a tunable antenna.