An 18.9-dB Dynamic-Range Rectifier Based on Time-Domain Modeling and Quality Factor

This letter presents a design of 433-MHz rectifier for wireless power transmission (WPT) in medical implant devices (MIDs). By modeling microwave Schottky diode in the time domain, the dc voltage and the optimal input impedance can be obtained at the high input power range when the current waveform at each input power was determined and implemented. At the input terminal, a pair of shunt capacitors were connected with the series and shunt inductors to improve the quality (Q) factor of matching network, which enhanced the rectifier efficiency in the wide input power range. By using lump elements in matching network, the 1.1 cm × 0.4 cm compact-size rectifier had the measured efficiency above 50.1% where the input power from -6.8 dBm (0.209 mW) to 12.1 dBm (16.22 mW) and thus, the dynamic range of 18.9 dB achieved. The peak efficiency was 64.4% at 5 dBm (3.16 mW).