COMPACT PATCH ANTENNA DESIGN FOR OUTDOOR RF ENERGY HARVESTING IN WIRELESS SENSOR NETWORKS

Abstract

In this paper, two compact patch antenna designs for a new application | outdoor RF energy harvesting in powering a wireless soil sensor network | are presented. The flrst design is a low-proflle folded shorted patch antenna (FSPA), with a small ground plane and wide impedance bandwidth. The second design is a novel FSPA structure with four pairs of slot embedded into its ground plane. Performance of both antennas was flrst simulated using CST Microwave Studio. Antenna prototypes were then fabricated and tested in the anechoic chamber and in their actual operating environment | an outdoor fleld. It was found that the FSPA with slotted ground plane achieved a comparable impedance bandwidth to the flrst design, with an overall size reduction of 29%. Simulations were