Dynamic-Range Extension Technique Based on Balanced Rectifiers
A dynamic-range extension technique based on balanced rectifiers is proposed. It consists of two balanced rectifiers deliberately designed for different input power level such that high efficiency (η) can be acquired from low to high input power. Constant input impedance is meanwhile maintained over input power due to the balanced configuration. Efficiency over frequency is concurrently improved with the help of the second balanced rectifier. A prototype is implemented to show the concept. Measured peak η is 67.8% at 2.45 GHz and S11 over entire input power is below -17dB. Input power for η above 50% is from 10.2 dBm to 26.3 dBm and thus, dynamic range (DR) of 16.1 dB is achieved. At 2.5 GHz the DR increases from 0 dB to 9.7 dB.