Diogenes Armando D. Pascua, Michael Lochinvar S. Abundo
Energy consumption is one of the biggest constraints of the wireless sensor nodes deployed in marine environment. They are typically used for remote environment monitoring in areas where providing electrical power is difficult. Therefore, the devices need to be powered by batteries and alternative energy sources. Because battery energy is limited, the use of different techniques for energy saving is one of the hottest topics in Wireless Sensor Networks(WSNs.) Various battery optimization schemes have been developed both through hardware and software techniques. The ubiquity of Wireless Fidelity(Wi-Fi) based networks makes for a popular choice for establishing Wi-Fi based sensor networks but the relatively high-power requirements of these systems conflict with the requirement for long battery life and low maintenance. This work considers whether it is possible to reduce Wi-Fi power usage to the point where cheap Wi-Fi based products can be used instead of other protocols. The setup is composed of a wireless sensor which is based on the low cost esp8266 module tasked to gather temperature data in a marine protected area. Energy consumption was analyzed for the nodes at various states along the device firmware as well as the relationship between energy consumption against the rate of sensor data of transmission and system sleep period. The study also compares the energy usage of two network implementation: Message Que Telemetry Transport(MQTT) against Server-Client based system. Test results reveal that the sensor nodes can have a maximum battery life of 15.8 hours for both transmission methods, regardless of transmission rates, if no sleep period is implemented. Transmission rate have a profound effect on the systems battery life if sleep mode is implemented. It was found that battery life can increase up to 43 times for a transmission period of one hour and up to 40 times for a transmission period of one minute. An optimized WSN configuration utilizing MQTT transmission scheme proved to extend battery life more than that of the Server-Client scheme by up to 34 percent. From these analyses, the design of an optimal firmware and choice of network architecture can be derived where battery life can be extended in the longest possible time. © 2020 IJSTR.
School of Engineering, Doctor of Engineering, University of San Carlos-Technological Center, Cebu, Philippines; Faculty of Engineering, College of Engineering and Architecture, University of Science and Technology of Southern Philippines, Philippines; Royce@NTU Corporate Lab, Nanyang Technological University, Singapore
