宽带圆极化整流天线设计

Design of Wideband Circular Polarization Rectenna

为了更好地利用空间无线电波RF能量,设计了一款覆盖谐振频率为1.7~2.6 GHz宽带圆极化整流天线。通过共面波导馈电,添加一个寄生贴片,实现宽频谐振。在主贴片外围采用环形贴片回路方式,通过电流相位差90°实现圆极化。在主贴片上进行E型开槽,实现宽带谐振和增强圆极化的目的。在HFSS下仿真,结果显示:天线的谐振频率为1.7~2.6 GHz,在1.8~2.4 GHz处的轴比AR<3 dB,1.7~2.6 GHz对应最大增益3.3~3.9 dB,天线总面积44×44 mm2。整流电路在源阻抗为50Ω时,1.7~2.6 GHz最大整流效率为79%;0 dBm输入功率条件下,最大整流效率为48.5%,对应的最大输出直流电压为0.69 V。

In order to make better use of the space RF radio energy, a wideband circularly polarized rectifier antenna with 1.7 ~ 2.6 GHz resonant frequency is designed. With a coplanar waveguide for feeding the Rectenna and the adding of a parasitic patch, the broadband resonance is achieved. Circular patch circuit is adopted in periphery of the main patch, and the circular polarization is realized by the current phase difference of 90°.By chiselling a E-slot on the main patch, the goal of broadband resonance and enhanced circular polarization is achieved. The simulation results indicate that the resonant frequency of the antenna is 1.7 ~ 2.6 GHz, the circular polarization bandwidth（AR 3 dB） at 1.8 ~ 2.4 GHz, the maximum gain 3.3 ~ 3.9 dB at 1.8 ~ 2.4 GHz, the total area of the antenna 44×44 mm2. The maximum rectification efficiency is 79% with rectifier circuit at source impedance of 50 Ω and 1.7 ~ 2.6 GHz. And the rectification efficiency reaches 48.5% at the input power of 0 dBm conditions, while the corresponding output DC voltage is 0.69 V.