Design of a Compact High-Gain Slotted Trapezoidal Antenna at 2.45 GHz For Energy Harvesting

In this paper, a compact, high gain, simple design, and high efficient single layer slotted dipole antenna is presented. The proposed antenna is fabricated on a low-cost commercial FR4 substrate and is suitable for RF energy harvesting applications. The antenna design relying on a simple modified trapezoidal dipole antenna patterned with a rectangular slot to minimize the inductive loading on the input impedance. A four-arms of a trapezoidal structure are arranged on a half-circle configuration. The performance of the antenna is studied using the simulation and experimental measurements. The antenna offers the main lobe in the z-plane direction with more than 6.5 dBi gain. The input reflection coefficient is measured at 2.45 GHz with a bandwidth extending from 2.4 to 2.5 GHz. The antenna has a small footprint and its dimensions are 32 × 34 mm².

I. Introduction

Miniaturization technologies have promised to build antennas an order of magnitude smaller than was possible 10 years ago without performance degradation. In many wireless devices, antennas occupy the majority of the circuit footprint. As size of the devices become a greater focus in industry, the demand for small antennas escalates. These size constraints place strict requirements on the communication system; the system frequency should be high in order to minimize the antenna size and thus the sensor unit [1].