Ultrawideband inkjet-printed monopole antennas for energy harvesting application

Multiple communication and identification systems are taking advantage of inkjet-printing techniques for the production of flexible, low-cost, and lightweight printed radiating elements. In this paper, we bring the advantages of inkjet printing to the design of efficient and low-cost wideband radio-frequency (RF) energy harvesters. We present the design, manufacturing, and measurement of two inkjet-printed ultrawideband monopole antennas. Both elliptical and circular monopoles are printed with a silver conductive ink on a thin polyethylene terephthalate film that lays on a foam substrate. Measurements show that the antennas operate efficiently from 0.6 to 8 GHz, covering the most relevant power contributions coming from the radio spectrum. In addition, the antennas show omnidirectional characteristics, highly desirable for broad spatial coverage in RF energy harvesting.