DESIGN AND IMPLEMENTATION OF MICROSTRIP PATCH ANTENNAAT 915 MHZ FOR RADIO FREQUENCY ENERGY HARVESTING APPLICATION

• Main Author: Dinata, Christian
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/65814
• Institution: Institut Teknologi Bandung

One of the most highlighted food sector in Indonesia is beef. Indonesia in fact, has to make a beef import regularly to satisfy the consumption rate of the people. This caused the importance of monitoring the beef quality before selling them to consumers or being consumed. The beef freshness rate can be estimated by evaluating the generated TVOC gas. However, the limitations of human senses in detecting the quality of the about to be sold or consumed beef less fresh. This case led to an alternative of beef monitoring system using an IoT sensor. Nonetheless, the usability of batteries in monitoring system in fact, is inefficient. It is because batteries’ waste are harmful to the environment and it is impossible to keep changing the used batteries with the new ones. Reflecting on the case above, this study proposed a beef monitoring system based on the TVOC gas rate. Energy Harvesting is applied as one of the backscatter technologies that harvested the radio frequency (RF) energy in the environment. The proposed system consists of a microstrip patch antenna which resonates at 915 MHz frequency. The data acquisition module is implemented using the CCS811 gas sensor and Wemos D1 Mini microcontroller. Besides, the user interface is a web application provided by w3spaces where the data is integrated with a versatile IoT platform, Thingspeak. The analysis of the 79.1 mm x 69 mm microstrip patch antenna showed a return loss of -16.664 dB and VSWR of 1.3437 at frequency of 915 MHz. The implemented antenna has wide operating frequency from 756.4 MHz to 1468.8 MHz although it has higher input impedance of 56.3 ohm.