ABSTRACT
The Power Amplifier (PA) is typically the last stage in a transmitter system. Its role is to provide the final amplification of signal power to a level that is large enough for microwave propagation through an appropriate antenna. In most modern commercial wireless systems, the PA and the associated driver amplifier determine the overall linearity of the transmit chain. One of the key considerations for a PA is the modulation scheme used. Many PA designs have been singletone Current wave, both in simulation and in physical measurement. The basic problem in designing a power amplifier is in regard to the output match. An inherent tradeoff must be made between gain and output power. Thermal design, especially in regard to the active-transistor region and how it is grounded will need to be considered. The terminal impedances of the transistor can be matched using reactive elements, such as capacitors and inductors.
