Design and Implementation of Miniaturized Antennas for Wireless Sensor Network Applications Using Particle Swarm Optimization

摘要

The present work introduces an automated optimization-based methodology for miniaturizing the size of a Fractal Planar Inverted-F Antenna (FPIFA) that can be used for Wireless Sensor Network applications. The methodology uses particle swarm optimization (PSO) algorithm. It was applied to the first four fractal (0th- 3rd) orders of FPIFA antenna. The optimization results reveal 68% reduction in area for the 3rd-order fractal PIFA antenna compared to the reference PIFA antenna. The third order miniaturized FPIFA has an overall size of (72.3 × 49.67 × 9.6) mm3 (i.e., λ/9.6 × λ/14 × λ/72, where λ is the free-space wavelength at 434 MHz). The PIFA antenna design is modified by reducing the substrate layer (by eliminating the foam material from the substrate layer). The optimization methodology is also applied to the first four Minkowski island fractal orders of the modified PIFA antenna (FMPIFA). A maximum reduction in area for the third FMPIFA antenna achieved was 86.5% compared to the RPIFA antenna. The 3rd-order fractal antenna has an overall size of (59.66 × 25.96 × 1.5) mm3 (i.e., λ/11.6 × λ/26.6 × λ/461) with an obtained volume reduction of more than 98% compared to the RPIFA antenna. Some of these models have been implemented practically. The practical and simulation results comparison shows a small frequency discrepancy.