Ceramic microwave antennas for mobile applications

Due to their medium to high permittivity values, ceramic microwave material s are attractive as building blocks for miniaturised antenna solutions. Fur ther advantages are low dielectric losses and an excellent temperature stab ility of standard ceramic materials. Yet, the permittivity of the ceramic m aterial also has a strong influence on the radiation efficiency and bandwid th of the antenna. This implies that in the design process a suitable compr omise has to be found between the degree of miniaturisation on the one hand and the antenna efficiency and bandwidth on the other. We describe two app roaches towards efficient miniaturised ceramic microwave antennas: the diel ectric resonator antenna (DRA) with partial metallisation and the shorting post patch antenna. We focus on design steps taken to ensure both a high de gree of miniaturisation and high values of the radiation efficiency, the ch oice of the ceramic material and the experimental performance of the antenn as. (C) 2001 Published by Elsevier Science Ltd. All rights reserved.