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A first-of-its-kind design methodology to realize thermally actuated origami-inspired multilayer Miura frequency selective surfaces (MLM-FSSs) using a polyester-based substrate is presented in this article that can change its frequency response according to the variation in its ambient temperature. In order to maintain the optimum interlayer distance between the two-layer Miura-FSS structures, a specialized low-loss origami-inspired spacer layer is introduced that preserves its desired overall frequency response during different folding configurations. It also features an unprecedented high mechanical strength, making it suitable for a wide range of terrestrial, outer-space, and biomedical applications. The frequency response and its relationship to kinematics of the proposed structure are also presented in detail, which gives a unique insight into the operation principles of such structures. The proposed structure features twice the bandwidth as compared to single-layer Miura-FSS, an excellent angle of incidence rejection, and is the first demonstration of a fully inkjet-printed MLM-FSS that is realized completely by a rigid heat-sensitive substrate as opposed to traditional cellulose-based Miura-FSSs that lack self-actuation mechanism as well as rigidity, which is a key attribute of most practical thick origami structures.

This paper discusses the design of a novel dual (solar + electromagnetic) energy harvesting powered communication system, which operates at 2.4 GHz ISM band, enabling the autonomous operation of a low power consumption power management circuit for a wireless sensor, while featuring a very good “cold start” capability. The proposed harvester consists of a dual port rectangular slot antenna, a 3-D printed package, a solar cell, an RF-dc converter, a power management unit (PMU), a microcontroller unit, and an RF transceiver. Each designed component was characterized through simulation and measurements. As a result, the antenna exhibited a performance satisfying the design goals in the frequency range of 2.4–2.5 GHz. Similarly, the designed miniaturized RF-dc conversion circuit generated a sufficient voltage and power to support the autonomous operation of the bq25504 PMU for RF input power levels as low as −12.6 and −15.6 dBm at the “cold start” and “hot start” condition, respectively. The experimental testing of the PMU utilizing the proposed hybrid energy harvester confirmed the reduction of the capacitor charging time by 40% and the reduction of the minimum required RF input power level by 50% compared with the one required for the individual RF and solar harvester under the room light irradiation condition of 334 lx.