Gain optimization of a seven element ESPAR Antenna using Quasi-Newton method

Similar to conventional adaptive arrays, ESPAR Antenna is an adaptive solution that can create and steer both radiation lobes and nulls in arbitrary directions. The radiation pattern is controlled by varying the DC voltage across varactors loading the parasitic elements that surround a feed element. Due to it´s low cost, compact size, uncomplicated structure and low power requirements, the antenna has immense potential to be massively embedded in handheld devices. A seven element ESPAR Antenna for 2.45 GHz was designed in HFSS. Optimization of the Antenna´s Radiation Pattern for a certain requirement was done in MATLAB, employing the BFGS - Quasi Newton Method. The results were used for simulation in HFSS which revealed remarkable accuracy in beam and null positioning, with a maximum directivity of 8.73 dB_i.