In this letter, a multioctave voltage doubler rectifier using a T-type matching network is demonstrated. The voltage doubler topology is used to flatten the load impedance, which makes it easier to achieve broadband impedance matching. The T-type matching network is used for the broadband input impedance matching. The design procedure of the proposed broadband rectifier is provided and discussed. For validation, a rectifier prototype is fabricated, and the performance is evaluated. The measured results exhibit power conversion efficiency (PCE) of more than 50% over a frequency band of 0.2–3.2 GHz at 15 dBm input power and 70% from 1 to 2.7 GHz. Moreover, the peak PCE is 78.2% at 1.9 GHz when the input power is 18 dBm.

To reduce the weight of a satellite, an internal wireless system (IWS) for satellites was proposed in a previous study. It is a system that can communicate between the satellite’s subsystems by using wireless communication modules. In this paper, we propose a complete IWS for a satellite using microwave wireless power transmission technology. The design of a 5.8-GHz high efficiency rectifier circuit-based charge pump circuit is also presented. Furthermore, we introduced a class-F load that can process the third harmonic components. The rectifying efficiencies of a normal charge pump rectifier and a charge pump rectifier with the class-F load are theoretically compared. To improve the conversion efficiency of the charge pump rectifier, the applied voltages of diodes are adjusted. Owing to inserting the class-F load and adjusted the applied voltage of diodes in this circuit, the conversion efficiency of the charge pump circuit at 30 mW increases to about 78% at 30 mW in the simulation, and to about 71% conversion efficiency in the experiment. In addition, the output voltage is higher than 5 V at an optimal load 1300 $\Omega $ .

To achieve a high-efficiency microwave wireless power transfer system, a high conversion efficiency rectifier is necessary. Brown (1974) designed rectifiers with approximately 3-W input power achieved 90% conversion efficiency for 2.45 GHz, and it maintains the record for maximum conversion efficiency. In this study, to design a high-efficiency and high-power rectifier, we designed a larger semiconductor metal junction area GaAs Schottky diodes possessing very low series resistance and high breakdown voltage. In addition, we built the SPICE model and package model for the diodes. The designed high conversion efficiency rectifier achieved 91% efficiency at 5-W input power for 2.45 GHz.

A novel co-designing strategy is presented for an integrated rectifying metantenna, which combines rectification, absorption and electromagnetic signal reception functionalities for simultaneous wireless information and power transfer (SWIPT). The metasurface is constructed using periodic patch units arranged in front of a compact microstrip antenna. This arrangement effectively stimulates transverse electric (TE) and transverse magnetic (TM) surface waves, which ensures not only high gain but also optimal antenna matching. Furthermore, the metasurface incorporates rectifier diodes distributed partially, significantly enhancing energy conversion efficiency. The proposed rectifying metantenna operates at 5.8 GHz (an ISM band) and achieves a maximum energy conversion efficiency of 54.6% when subjected to an input power of 0 dBm. This accomplishment is particularly noteworthy when the metantenna is integrated into devices for data communication. The proposed rectifying metantenna boasts a range of merits including high integration and multifunctionality. These inherent attributes position it as a promising candidate for advanced IoT wireless communication systems, facilitating the generation of rectified DC power while receiving RF signals without the need for power splitter and time-switching used in conventional SWIPT systems.

Microwave power transfer (MPT) can solve certain types of problems. For example, Internet of Things requires a flexible configuration of sensor networks, which is hindered by wired-charging sensors. This problem can be overcome by MPT techniques. However, the transmission efficiency of MPT is lower than that of wired transmission. This study focuses on the operation of rectifiers having a pulse-modulated input signal. Although a pulse-modulated wave is effective for improving the RF-DC conversion efficiency, the output voltage waves of rectifiers have a high ripple content. Moreover, the harmonic balance method cannot be used to simulate the operation of a pulse-modulated rectifier. To reduce the ripple content, a smoothing capacitor should be connected in parallel to an output load. We investigated the influence of a smoothing capacitor, the general characteristics of rectifiers under pulse-modulated waves, and the effectiveness of using pulse-modulated waves for improving RF-DC conversion efficiency. In conclusion, we reveal a necessary condition of the smoothing capacitor for improvement, demonstrate the effectiveness of pulse modulation, and show that the optimum impedance with a pulse-modulated wave input is an inverse of duty ratio times as compared to that with continuous wave input.