Radio frequency energy harvesting is one of the new renewable sources that faces some technical challenges, which limit its performance. This study presents two scenarios to enhance the harvested power. The first scenario introduces a quad-band voltage multiplier circuit with a single receiving antenna and four band-pass filters of elliptic type. In this scenario, four frequencies of the Global System for Mobile communications, Universal Mobile Telecommunications System, and Wireless Fidelity frequency bands have been considered for the study. The second scenario proposes a quad-band voltage multiplier circuit with four receiving antennas at the same frequency bands as the first scenario. High conversion efficiencies were achieved for the two scenarios. The proposed quad-band system developed a harvested power level, sufficient for powering up low power micro-devices with no need for an external power supply.

中文翻译：

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四频带射频电路，用于增强能量收集

射频能量收集是新的可再生能源之一，它面临一些技术挑战，从而限制了其性能。这项研究提出了两种方案来增强采集的功率。第一种情况介绍了一种具有单个接收天线和四个椭圆型带通滤波器的四频带电压乘法器电路。在这种情况下，已考虑了全球移动通信系统，通用移动通信系统和无线保真频段的四个频率进行研究。第二种情况提出了一种四频带电压倍增器电路，该电路在与第一种情况相同的频带上具有四个接收天线。在两种情况下均实现了高转换效率。拟议的四频带系统开发了一个已采集的功率电平，