Effects of battery characteristics on communications for miniature wireless sensor network

• Main Author: Tan, Zheng Ru.
• Other Authors: Wong Kai Juan, Steven
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Computer science and engineering::Hardware::Input/output and data communications
• Online Access: http://hdl.handle.net/10356/16954
• Institution: Nanyang Technological University

This project investigates the effect of using long or short data packets on the battery life in a miniature sensor node. The focus is on modifying only the communication aspect of the miniature sensor node, specifically the wireless radio transceiver behaviour to achieve the purpose of extending battery life. The project aims to show that shorter data packets can be used to take advantage of the relaxation phenomenon present in batteries to extend overall battery lifetime of the sensor node. 3 experiments were designed to compare the battery life of miniature sensor nodes using long or short data packets. ProSpeckz IIK was used as a prototype to simulate miniature sensor nodes because it is easily reprogrammable with the software PSoC Designer. The first and second experiment set a specific but different data lengths for long and short data packets, varying the transmission strength of the radio transceiver. The third experiment emulates long and short data packets by cycling the radio transceiver on and off in different time intervals. Battery voltages during the experiments were captured and logged using the oscilloscope and the software WaveStar. In the first and second experiment, the long data packets last significantly longer than short data packets. This was due to the duty cycle of long data packets being longer than that of short data packets. It was corrected in the third experiment where both duty cycles are equal and the short data packets last longer than long data packets. This result indicates that short data packets are able to capitalize on the relaxation phenomenon in the battery to enhance battery life.