Design and Implementation of a 915 MHz Microstrip Antenna for LoRa-Based Livestock Tracking Systems

Abstract

Long Range (LoRa) is a wireless communication technology based on Low Power Wide Area Network (LPWAN), distinguished by its long-range transmission, low power consumption, stable, and secure data. This technology enables livestock owners to continuously monitor the position and movement of animals via the LoRa network, enabling faster and more precise responses to potential loss or theft. This study aims to design and implement a microstrip antenna as a primary component in a LoRa-based tracking system operating at 915 MHz. The antenna was designed using an FR-4 Epoxy substrate (εr = 4.4, thickness of 1.6 mm) through theoretical calculations, simulations using CST Studio Suite 2019, dimension optimization, fabrication, and testing via a Vector Network Analyzer (VNA). The results demonstrate that the system reliably transmits coordinate data with a Packet Delivery Ratio (PDR) of 100% at 100 m, 95% at 200 m, and 50% at 1000 m. Furthermore, the system produces minimal GPS coordinate deviations, specifically 0.02897% for latitude and 0.000127% for longitude. The fabricated antenna achieved a return loss of -20.60 dB, a VSWR of 1.20, a bandwidth of 20.3 MHz, and a maximum gain of 4.301 dB. Users can access the real-time tracking system through an Android application developed with MIT App Inventor.