Dual-Band Dual-Mode Printed Bow-Tie Antennas Integrated in Handheld Terminals for Wireless Communications

The rapid increase in the use of dual-band dual-mode handsets worldwide has aroused the need for more compact terminals. Although the monopole has demonstrated to endorse large specific absorption rate (SAR) values, manufacturers still rely on it as the handset antenna for new dual-mode terminals, with some commercial devices even exhibiting a dual-monopole configuration. This extension to higherfrequencies for the new, generation ofcellular systems can lead to increased electromagnetic absorption in the human body, making the new mobile communications equipment an issue of public health concern. In this paper, several attempts to accomplish dual-band GSA/DCS 1800 operation on a single terminal are described While keeping similar radiation characteristics, a tremendous SAR reduction has been obtained by using printed bow-tie antennas compared to the ¿-wavelength monopole.