The pattern selection capability of a printed ESPAR antenna

The research work presented in this paper involves a proof-of-concept indoor experiment that demonstrates the beamforming capability of an Electronically Switched Parasitic Array Radiator (ESPAR) antenna. A new 3-element ESPAR antenna, formed by one active and two parasitic printed monopoles, is proposed. Two prototypes, which operate at 3.55 GHz, are modeled, fabricated and measured, exhibiting a reconfigurable pattern (three operating modes) and a satisfying directivity increase between the omni-directional and the two directional states. The two ESPARs are embedded in a IEEE 802.11p transceiver, in order to perform a beam selection concept in an indoor environment and evaluate the overall performance in a system level. When the two antennas focus their radiations patterns towards each other, an average of more than 6.5 dB Signal to Noise Ratio (SNR) gain is achieved, compared to the omnidirectional mode.