A dual-frequency rectenna is introduced in this paper. An enhanced-gain antenna is integrated with the rectifying circuit for increasing the rectenna capability for scavenging. A voltage doubler circuit is used for the rectification. Moreover, a four-section matching network is employed for the matching between the antenna and the rectifier. The measured results reveal that the RF-to-DC conversion efficiency is more than 50% over wide range of the input power, from-3.5dBm to 10. 5dBm at f1 and from -4.5dBm to 11dBm at f2, with maximum conversion efficiency of 63% and 69% at input power of 7dBm and 3. 5dBm, respectively with resistive load of 1KΩ. Further-more, the measurements illustrate good agreement between the simulated and measured results.