Wireless power-data transmission for industrial internet of things: Simulations and experiments

One of the key challenges in the practical realization of industrial internet of things (IoT) is overcoming Faraday shielding of free space electromagnetic waves emanating from the antennas of wireless systems used for power and data transfer. Metallic structures, machinery, pipeline, etc., cause interference resulting in the loss of signal connectivity among sensor network. Currently available techniques based on ultrasonic-electromagnetic transducers pose severe limitations on frequency, efficiency, and alignment. Here we demonstrate exciting Zenneck type interface waves propagating as localized charge oscillations (modes) along the metal profile, which overcomes the restrictions on frequency, metal obstacles, partial enclosures, and alignment. A finite element methods (FEM) model developed to predict the signal reception and power transfer efficiency across metal infrastructure shows excellent agreement with the experimental results. Electrical power transfer using Zenneck, under open conditions, show 4% drop for distance of 1 to 8 meters (68 to 64%), and 9% drop under shielded conditions for the same range (66 to 57%). For data transmission results, we demonstrate a feasibility, for an input power of 0dBm with several metallic pipelines as obstacles show received power of -11.8 dBm and -19.01 dBm at 6 and 25 meters, respectively.