MEMS-based parametric amplifiers for range optimization of wireless sensor networks
Lusatia and the state of Brandenburg, home of our application partner, have numerous remote regions as well as sparsely populated areas, which is also found in many other regions of the world. In this context, a digitization of measuring points is a major challenge; be it for groundwater/water, forest fire, structure, infrastructure or terrain monitoring in post-mining landscapes as well as in digital agriculture. Especially the radio interface for networking sensors with cloud applications or base stations limits the range in many cases, which makes coverage in highly distributed scenarios difficult. On the one hand, the required long ranges are problematic, on the other hand, an efficient use of the limited battery capacity at remote locations without central energy supply. In many cases, decentralized energy generation, e.g. with the help of photovoltaic cells, can ensure self-sufficient operation in the long term. But especially in professional and industrial use, there are many applications where solar energy or other sources are not available in sufficient quantities or where size and weight limitations prohibit harvesting concepts. Therefore, there is a great need for purely battery-powered wireless sensor nodes that nevertheless guarantee a long runtime. At the same time, the individual measuring points are often widely distributed, which requires a lot of energy for transmission and reception. The core of the project applied for here is an energy-efficient generic sensor node. Since the radio interface has the highest energy demand of all components, this is the focus of this project. Based on the findings on the design of resource-limited sensor nodes from the preliminary DFG project FOR 1508, the system approach found there will be pursued further and an innovative, power-saving amplifier technology will be specifically added to the radio interface in order to increase the range of the wake-up receiver (WuRX) in an energy-efficient manner. New technological approaches are to be used to extend the technical usability and thus pave the way towards commercialization of the system. The basic idea is to generate energy for the amplifier from a high-frequency excitation, which is possible thanks to a mechanical oscillator resonance. This would solve the two biggest challenges of the existing WuRX - energy consumption and short range. The sensor node equipped with a MEMS paramp thus becomes the ideal solution for professional sensor networks extending over wide areas. The application partner Actemium BEA will demonstrate the applicability of the system designed in the project in the field on its automation systems and machines, for example in conveyor technology for open-cast mining or decentralized measuring points.