BER Performance of Planar ESPAR Antennas in 2 2 MIMO Transmission in an O ce Environment

An adaptive array antenna which can be controlled by using variable capacitors has been reported [1]. This antenna is known as the electronically steerable parasitic array radiator (ESPAR) antenna. The ESPAR antenna has an excited element and some parasitic elements, which are loaded with a variable capacitor. By controlling the bias voltages applied to the variable capacitors, the beam steering is achieved and the transmission performance can be increased. While a planar ESPAR antenna composed of patch antennas has also been reported instead of monopole antennas [2], it is better implemented on mobile applications. In this report, the bit-error-rate (BER) performance of the planar ESPAR antenna is represented in a 2 × 2 MIMO transmission scheme through a measurement in an office environment.