Article

Fundamental Modulation Limits for Minimum Switching Frequency Inband-Error-Free High-Efficiency Power Amplifiers

Dept. of Electron. Eng., Tech. Univ. of Catalunya (UPC), Barcelona, Spain
Circuits and Systems I: Regular Papers, IEEE Transactions on (Impact Factor: 2.24). 11/2011; DOI: 10.1109/TCSI.2011.2123570
Source: IEEE Xplore

ABSTRACT This paper explores the modulation bandwidth limits for switching amplifiers, by analyzing the fundamental tracking capabilities of two-level switching signals. With this aim, this work synthesizes two-level switching signals by obtaining the distribution of switching events providing both minimum average switching frequency and inband-error-free encoding, targeting to minimize the amplifier switching losses when tracking a generic bandlimited signal. This analysis also provides a framework reference to characterize the deviation from such limit in modulations used in actual amplifiers.

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