SUMMARY
We present an efficient rectenna capable of harvesting ambient radio frequency energy to obtain utilizable direct current power at a frequency of 2.45 GHz. The rectifying antenna incorporates a fractal structure at its antenna section. The unique space‐filling property of fractals is implemented to develop an antenna with a significant size reduction. A Sierpinski carpet, which is a simple and effective fractal design, is edge‐fed and iterated up to the 3rd order. The received signal from the 2nd‐order fractal iterated patch antenna is rectified using a rectifier circuit that uses an HSMS 8202 (Avago Technologies, California, USA) diode. The realized rectenna has the capacity to exhibit a maximum efficiency of 57% at an input power level of 20 dBm. Simulations for the fractal iterated patch antennas and rectifier circuit are performed in Ansoft HFSS, Ver. 10 (Ansys, Canonsburg, USA) and ADS (Agilent Technologies, Mississauga, Canada), respectively. The simulated antenna and rectenna are experimentally tested to verify the simulation results. The simulation and experimental results for the antenna and rectenna design are found to be in good agreement with each other. Copyright © 2013 John Wiley & Sons, Ltd.