Cross-Configured Directional UWB Antennas for Multidirectional Pattern Diversity Characteristics

A cross configuration of directional ultrawideband (UWB) antennas for multidirectional pattern diversity characteristics is presented. Initially, a printed UWB circular monopole having an asymmetric curve shaped CPW feed is designed as a base antenna for obtaining a directional radiation pattern, direction of which remains fairly same for the entire UWB. This base antenna is attached to similar antennas, in a four element cross-configuration to achieve multidirectional pattern diversity characteristics. The proposed structure provides high inter-element isolation of more than 20 dB, with an impedance bandwidth of 19.7 GHz, i.e., 1.3 GHz to 20 GHz. Transmission and diversity characteristics of the proposed antenna are analyzed. Good agreement between simulated and measured results indicates that the proposed antenna is suitable for UWB pattern diversity applications.