Oscillating quiescent point in power amplifier biasing

Abstract

Biasing is an essential feature of any electronic circuit. The traditional method of biasing involves applying a proper DC to fix the operating point and thereafter ensure its stability. In this paper, we have proposed a new concept of transistor biasing. Instead of a fixed quiescent point which is normally established by giving DC input to the transistor for the purpose of biasing, we have proposed an oscillating quiescent point by giving square wave biasing input, so that the quiescent point would be oscillating between the two ends of the load line. During the positive half cycle of the input signal the quiescent point would be at the bottom of the load line near the cutoff region, while during negative half cycle of the input signal, the quiescent point would be at the top of the load line near the saturation region, thereby giving full cycle operation for the signal excursion in the active region. The linear range of amplification is better exploited to give higher amplification with negligible distortion and high efficiency.