부산대학교 도서관

Miniaturized antenna system for the safety of miners in an underground mine for providing communication has been presented in this paper. Miniaturization of the proposed antennas is achieved by using printed inverted-F and inverted-L elements. The impedance bandwidth of the proposed antenna geometry for GSM application is over 16%. Measured and simulated characteristics of the antenna agree very well. The measured gain of the antenna, with a two-director, is over 4.98 dBi when mounted on a ground plane and around 5.2 dBi when placed on the wall of an underground mine. Proper placement of the antenna in the mine environment is discussed for better communication for miners. Experimental validation of the antenna system is performed in a real underground mine. The radiation performance of the system is also studied in the mine environment. The proposed antenna may be suitable for establishing communication in underground mines to ensure the safety of miners.