RF power amplifier characterisation: from device to system level

RF power amplifier (PA) designers aim to build linear and efficient transmitters. Linearity is essential to preserve/avoid corrupting the data to be transmitted and must be higher than a minimum value imposed by wireless communication standards. Efficiency is a desired performance that leads to wasting as little energy as possible resulting in: improved battery life of portable devices, reduced running cost of base-stations of mobile network infrastructures and TV transmitters/broadcasters. It is also good for our planet!
Linearity and efficiency are contradictory design goals in simple PA modes of operation that can be either linear or highly efficient. Current design flow consists then of; firstly designing a highly efficient PA module that ensure little waste of energy over the most relevant dynamic range of the signal to be amplified, and secondly, cancelling out the unavoidable nonlinear behaviour. This talk covers then the characterisation of RF power transistors for single branch PA design, some highly efficient architectures, and finally, the associated linearisation procedures. Hopefully, by the end of this talk, the attendants will have a general idea about the RF instrumentation used and the important parameters to keep a close eye on for each of the design steps of a linear and efficient PA.