A 19.6 dB Input Power Range 403 MHz Rectifier Based on Quality Factor in Matching Technique

To extend the input power range and increase RF sensitivity for energy harvesting in medical implant communication service (MICS) band, a high quality (Q) matching network is applied in 403 MHz rectifier circuit. In this proposed design, a finite unload Q series inductor is placed between a pair of shunt capacitors to enhance the overall load Q factor of impedance matching network when compared with conventional type. By using lump components, the compact size of rectifier is 1.4 cm x 0.8 cm that suitable for medical implant devices in human body tissue. The compact-size rectifier has the measured efficiency $(\eta)$ where the input power range for $\eta$ above 50.1 % is from -8.1 dBm (RF sensitivity) to 11.5 dBm and thus, the input power range of 19.6 dB is achieved. At 5 dBm the peak efficiency is 68.1 %.