RF power amplifier

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An RF power amplifier is a type of electronic amplifier used to convert a low-power radio-frequency signal into a larger signal of significant power, typically for driving the antenna of a transmitter. It is usually optimized to have high efficiency, high P1dB compression, good return loss on the input and output, good gain, and good heat dissipation.

[edit] Wideband amplifier design

Impedance transformations over large bandwidth are difficult to realize, thus most wideband amplifiers use 50 Ω output loading. Transistor output power is then limited to

Pout \le \frac{(V_{br} - V_k)^2}{8Z_o}

Vbr is defined as the breakdown voltage

Vk is defined as the knee voltage

and Z_o = 50\Omega\,