Energy harvesting powered wireless sensor systems are gaining increasingly popularity, since they enable the systems to be self-powering, long lasting, almost maintenance free, and environmentally friendly. However, the mismatch between the energy generated by the harvesters and the energy demanded by the systems to perform the required tasks is always a bottleneck as the ambient environmental energy is limited and the wireless sensor systems are power hungery.
Our wireless sensing focuses on proposing, designing, implementing and testing the energy-saving and energy-efficiency mechanisms for both wireless sensor nodes and wireless sensor networks to deal with the energy mismatch. We aim to enable the wireless sensor systems to be powered by energy harvesting technologies in the condition of limited power supply from the energy harvesters, achieving more sensors to be connected, more measurements to be taken, and more complex monitoring functions, e.g., synchronization and collaboration, to be implemented for real-world applications.
Our research areas in wireless sensing include:
• Energy-aware approaches
• Low power sensor interfaces
• Low Power Wireless communication technologies
Our energy-aware approaches are to incorporate energy awareness hardware and software in energy harvesting powered wireless sensor systems. They are able to reduce the power consumption and perform a required wireless sensing task based on the available energy harvested level by targeting all stages of energy harvesting powered wireless sensor systems from the underlying hardware components to the application software and networks. The sub-areas we are researching include:
- Hardware energy-aware interface
- Software energy-aware programme
- Network energy-aware algorithm
Our research focuses on efficient and effective low power sensor interfaces and techniques, allowing sensing to have a low power operation and enabling energy harvesting to power wireless sensor systems for real-world application. Our mechanism is to control the on and off states of the sensors when they are powered. Some examples we have developed are:
- Low power sensing circuit for RADFET based radiation sensing
- Strain measurement using a single piece of piezoelectric transducer that is also used as the energy harvester have been developed
- Single Piezoelectric Transducer as Strain Sensor and Energy Harvester Using Time-Multiplexing Operation
- A multifunctional device as both strain sensor and energy harvester for structural health monitoring
- Ultra-low-power RADFET sensing circuit for wireless sensor networks powered by energy harvesting
We use standard low power wireless communication protocols and technologies to study energy harvesting powered wireless sensor nodes and we study:
- Long- range wireless communication technologies. They can be used for Internet of Things (IoT) applications, including smart cities, buildings, agriculture, metering, logistics and supply chain, and industrial control. The operating range of the technology varies from a few kilometers in urban areas to over 10 km in rural settings.
- Shor-range wireless communication technologies. They can be used for industrial monitoring systems, smart metering, home and commercial building automation and location aware services. The transmission distance of the short-range wireless communication technologies is normally within 10 m but is able to go up to 100 m.