提出了一种工作在低输入功率环境下的具有功率自适应功能的915 MHz整流电路. 该整流电路适用于较宽的输入功率环境, 利用一个场效应管作为自适应开关, 根据输入功率的大小切换整流电路工作模式, 使其能够在一个较宽的输入功率范围内高效整流. 该电路输入端使用双枝节匹配网络将二极管输入阻抗匹配至50, 输出端并联一电容作为直通滤波器, 使得输出功率平稳. 仿真结果表明: 在−16~4 dBm 的输入功率范围内, 整流效率高于40%, 最高转换效率为66.2%. 实测最佳工作频率有所偏移, 最高转换效率为47.5%. 可见该整流电路采用简单的平面印刷电路工艺, 易集成, 可用于环境电磁能量收集.

This paper proposes an adaptive power rectifier at 915 MHz operating in a wide range of low input power. A field effect transistor works as an adaptive switch for changing the working modes of the rectifier according to the input power level. As a result, the rectifier can achieve high MW-DC conversion efficiency over the entire range. A double-stub matching network matches the input impedance of the diode to 50 . A shunted capacitor works as a DC-pass filter to smooth the output DC power. Simulation results show that efficiency is above 40% within an input power range from −16 to 4 dBm, and the maximum efficiency is 66.2%. The measured center frequency shifts a litter and the maximum efficiency is 47.5%. The rectifier is fabricated using a simple planar printed circuit board (PCB) technique, and is easy to be integrated. It can be used to collect ambient electromagnetic energy.