Compact spiral antennas for multiband and wideband operations

Modern communication system demands compact devices that operate over a wide range of frequencies. These systems require minimum sized antennas. Two miniaturized spiral configurations (rectangular and circular) that offer wide bandwidth and multiband operation is proposed in this paper. The structures use spiral configuration to achieve size reduction and wideband/ multiband operation. The rectangular spiral antenna is a compact microstrip line fed antenna having dimensions 2 cm × 2 cm × 0.16 cm and operates from 1.64 GHz to 8.2 GHz and 8.5 GHz to 10.5 GHz. The circular spiral antenna has dimensions 4.7 cm × 4.7 cm × 0.16 cm and offers multiple bands from 5GHz to 12 GHz, 12.4 GHz to 14.8 GHz and 15.1 GHz to 19.6 GHz.