A Broadband High-Efficiency Rectifier Based on Two-Level Impedance Match Network

A broadband high-efficiency rectifier with shunt-diode circuit topological structure is presented in this paper. By utilizing the two-level impedance match network, the rectifier can achieve a high microwave-direct current (mw-dc) conversion efficiency within a broad range of operation bandwidth. A stepped microstrip line and a cross-shaped microstrip stub as two-level match network is designed to extend the operation bandwidth. A cross-shaped stub connected to the capacitances act as a dc-pass filter to block the fundamental frequency wave and the high order harmonics and further improve mw-dc efficiency within a broad bandwidth. Experimental results show that the peak conversion efficiency is 80.3% at the frequency of 1.9 GHz when the input power is 22 dBm. When the input power is 19.5 dBm, the bandwidth of efficiency higher than 70% is 40% (1.80 GHz-2.72 GHz). This rectifier has the characteristics of low profile and easy integration, which is suitable for RFIDs, WSNs, and other applications.