Theoretical Analysis of BJT Cl...

Theoretical Analysis of BJT Class-F Power Amplifier Chapter 2 THEORETICAL ANALYSIS OF BJT CLASS-F POWER AMPLIFIER

The concept of class-F power amplifier is based on the realization of open-circuit and short-circuit conditions for the higher harmonics at the transistor output17. The third harmonic peaking class-F is the widespread case of such power amplifiers18-23. The input impedance of output network represents the zero resistance for the second harmonic frequency and infinite value for the third harmonic frequency ideally. The transistor output current and voltage impulses become half-wave truncated cosinusoidal and square-wave waveforms, respectively. This leads to the collector efficiency increasing due to the dissipated in transistor power decreasing. However, the above mentioned short-circuit and open-circuit requirements are not su