Abstract
A new low cost switched-beam antenna array suitable for 2.4 GHz ISM applications is presented in this paper. The proposed structure consists of four planar inverted-F antennas (PIFA), sharing the same ground plane, in a configuration designed for symmetrical coverage of the horizontal plane (Quad-PIFA). A custom Genetic Algorithm (GA) is used in order to optimize the array parameters regarding resonation frequency and radiation pattern orientation angle and beamwidth. The optimized Quad-PIFA exhibits low profile (size equal to 8 cm × 8 cm), high front to back ratio (15.6 dB), and satisfactory directivity (3.6 dB) over an operational bandwidth of over 200 MHz. Simulation and measurement results are presented indicating consistency between design and implementation and demonstrating the performance of the array.