In this letter, an efficient and compact tri-band rectifier with large frequency ratio is proposed, which adopts a novel low-cost direct current (dc)-pass filter structure in the design. Three large frequency ratio rectifiers are combined together by using diode arrays with a frequency-selective topology without additional impedance matching networks. The dc-pass filter is composed of microstrip line structures cascaded low-cost lumped components, which can effectively suppress the high-order harmonics at high- and low-frequency points while reducing the circuit size and costs of large frequency ratio. For validation, the proposed rectifier working at 0.915, 2.45, and 5.8 GHz is fabricated with the dimensions of 29.5 mm $\times21.3$ mm. The measured results show that the RF-dc power conversion efficiency (PCE) reaches 72.6%, 71.8%, and 73.5% at 0.915, 2.45, and 5.8 GHz, respectively, when the input power is 19 dBm. Compared with traditional multiband rectifiers, the proposed topology exhibits merits of compact size, high efficiency, and large frequency ratio.

中文翻译：

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用于 WPT 的高效紧凑型大频率比三频整流器

在这封信中，提出了一种高效紧凑的大频率比三频整流器，在设计中采用了一种新颖的低成本直流（dc）通滤波器结构。三个大频率比整流器通过使用具有频率选择拓扑结构的二极管阵列组合在一起，无需额外的阻抗匹配网络。直流通滤波器由微带线结构级联低成本集总元件组成，可有效抑制高低频点的高次谐波，同时减小大频比的电路尺寸和成本。为了验证，所提出的工作在 0.915、2.45 和 5.8 GHz 的整流器被制造成尺寸为 29.5 mm $\times21.3$毫米。实测结果表明，当输入功率为 19 dBm 时，RF-dc 功率转换效率 (PCE) 在 0.915、2.45 和 5.8 GHz 时分别达到 72.6%、71.8% 和 73.5%。与传统的多频段整流器相比，该拓扑结构具有体积小、效率高、频率比大等优点。