射频能量收集的小型化双频整流天线设计

Design and implementation of compact dual-band rectenna for RF energy harvesting

针对传统的双频整流天线转换效率不高的问题,提出了一种用于射频(RF,radio frequency)能量收集的双频整流天线。其工作频段为1.75GHz和2.45GHz,主要由接收天线、阻抗匹配电路、二倍压整流电路和负载电路组成。基于小型化双频天线,引入一种新型双频阻抗匹配网络,以提高整流电路在较低输入功率下的射频-直流(RF-DC)转换效率。此外,采用新型阻抗匹配网络使得整流电路复杂度得以降低,减小了能量损耗。与传统的双频整流天线相比,-10dBm输入功率条件下,在普通室内环境中新型双频整流天线具有更高的RF-DC转换效率。实验结果显示,在1.75GHz GSM频段和2.45GHz WLAN频段上最大RF-DC转换效率分别可以达到65.34%和54.3%。测试结果证明,其可以在物联网低功耗设备中得以应用。

A dual-band rectenna for radio frequency (RF)energy harvesting was proposed in view of the problem of low conversion efficiency of traditional dual-band rectenna.The rectenna is mainly composed of receiving antenna,an impedance matching circuit,a double voltage rectifier and a load circuit.Based on the miniaturized dual-band antenna,a new dual-band impedance matching network was introduced to improve the RF-DC conversion efficiency of the rectifier at a lower input power.In addition,the new impedance matching network reduces the complexity of the rectifier.Compared with traditional dual-band rectenna, the novel dual-band rectenna has higher RF-DC conversion efficiency in indoor environment for an incident power of-10dBm.The experimental results show that the RF-DC conversion efficiency reach 65.34% and 54.3%in 1.75GHz GSM band and 2.45GHz WLAN band,respectively.And the rectenna can be used in Internet of Things (IoT)low power devices.