Title :
Design of high efficiency power amplifier using DC and small-signal S-parameter measurements
Author :
Yi, Seung-June ; Kim, Byung-Sung ; Nam, Sangwook
Author_Institution :
Appl. EM-Wave Lab., Seoul Nat. Univ., South Korea
Abstract :
This paper presents a simple and fast design method for high efficiency power amplifier only using DC and small-signal S-parameter measurements. This method requires neither a large-signal model nor load-pull measurements, giving relatively accurate results. LSBP (Large-Signal Bias Point: shifted bias point at large-signal input) is predicted by waveform analysis, and small-signal S-parameters at LSBP are used in designing the matching circuits. Harmonic loading theory is adopted for high efficiency operation, but it is modified to apply to real devices. Many parasitic effects are fully analyzed, and it is proved that the finite output resistance limits the power efficiency. A 2 GHz band power amplifier is designed by the proposed method, and its output characteristics validate the proposed method
Keywords :
S-parameters; UHF power amplifiers; equivalent circuits; network synthesis; waveform analysis; 2 GHz; DC measurements; design method; finite output resistance; harmonic loading theory; high efficiency power amplifier; large-signal bias point prediction; matching circuits; parasitic effects; small-signal S-parameter measurements; waveform analysis; Design methodology; High power amplifiers; Impedance; Load modeling; Operational amplifiers; Power amplifiers; Power generation; Power measurement; Scattering parameters; Voltage;
Conference_Titel :
Microwave Conference Proceedings, 1997. APMC '97, 1997 Asia-Pacific
Print_ISBN :
962-442-117-X
DOI :
10.1109/APMC.1997.654591
