From Frequency Domain to Time Domain Multiplexing-Based SWIPT

Rolls and rotating machineries are quite common in industrial implants. As these parts are moving, they must be equipped with sensors to monitor their shear status and perform predictive maintenance. Nevertheless, energizing sensors on these platforms is challenging, since the sensors cannot be connected to the grid to avoid tangled cables. The use of batteries is also not ideal since they must be replaced periodically, thereby causing periodic shut downs in the production. WPT is therefore an ideal solution to provide a reliable energy source for sensors and electronics within the machinery. Currently, there are studies to demonstrate that the same front-ends used to transmit power can be used to transmit data. This way, the hardware can be reduced, and the same equipment can be used to provide power and to receive the sensor data. In this talk, an original solution will be described to perform wireless power and data transfer using the same channel. This solution in particular leverages a system of spirals, lying on different sectors of a roll. A single transponder is used in transmission, while two spirals are used to collect power and data in different moments of the rotation, thereby separating the two systems in time domain. Differences and comparisons with more conventional approaches where data and energy utilize different frequency bands will be emphasized.