of the RF-':Iarvesting system. The RF-Harvesting system IS divided Into the urnts: receiving antenna, the impedance transformation unit, the rectification unit and the load. To improve the efficiency the impedance of the receiving antenna has to be matched to the imput impedance of the rectifier circuit.Abstract-This paper presents a new method for rectifying low ambient radiation sources to supply autonomous measurement systems such as microsystems. An impedance transformation with high quality factor (Q) in front of a Schottky-Diode using a quartz resonator at 24 MHz is presented. In addition to an analytic computation and nonlinear simulation of the rectifier circuit with Advanced Design System (ADS) software, the circuit was built and the efficiency of the RF Energy Harvesting system was measured. The design has been optimized to achieve maximum sensitivity. The measurement results show a sensitivity of -30 dBm (1 p,W) for DC output voltage of 1 V and an efficiency of more than 22 %.