A Series-Fed Conformal Antenna at 60 GHz for 6G and Beyond Applications

This work deals with the design and development of a conformal series-fed antenna structure operating at the 60 GHz frequency. The proposed antenna operates from 57 GHz to 62 GHz with good return loss and radiation characteristics for 6G and beyond applications. The antenna is shown to give a good gain of more than 14.7 dBi with directional radiation beam in the hemispherical boresight direction. The fabricated prototype is verified with the simulated result, and it is found to be a good matching. The step-by-step antenna design process, parametric variation, and a detailed study are also reported. For a case study, this series-fed antenna conformal configuration is also embedded on a cylindrical structure. From this study, similar resonant and radiation performance characteristics are observed. Since the structure is compact, conformal, and gives better performance, it can be suitable for applications such as 6G, radar, guided missiles, body-centric medical imaging, etc

Dual-band low-power RF-to-DC signal converter circuits for energy harvesting

This article presents dual-band low-power, high-sensitive radio-frequency (RF)-to-direct current (DC) signal converter circuits, operating at 2.45 and 5.5 GHz bands, for radio frequency energy harvesting applications. In particular, it focuses on the lumped element and microstrip transmission line model circuits. The lumped element RF-to-DC converter circuit is composed of a dual-band impedance matching circuit, voltage-doubler rectifier, and DC-pass filter with a resistive load of 5 kΩ. This converter circuit gives a DC output voltage of 48 mV at 2.45 GHz and 25 mV at 5.5 GHz on −25 dBm input power. Maximum conversion efficiency is 47% at the 2.45 GHz band and 27% at the 5.5 GHz band when the input power is set to −10 dBm. Circuit design steps, matching conditions, performance parameters, and so on, are presented using Advanced Design System simulation. To validate the concept of the lumped element model, a microstrip transmission line RF-to-DC converter model is simulated and fabricated. It also composes of a dual-band matching network, voltage-doubler, and DC-pass filter with a load resistance of 5 kΩ. At a low input power of −18 dBm, it gives an output voltage of 21 mV in measurement. An appropriate match between the simulation and measurement is noted