LDMOS versus GaN RF Power Amplifier Comparison Based on the Computing Complexity Needed to Linearize the Output

Abstract

In order to maximize the efficiency of telecommunications equipment, it is necessary that the radio frequency (RF) power amplifier is situated as closely as possible to its compression point. This makes its response nonlinear, and therefore it is necessary to linearize it, in order to minimize the interference that nonlinearities cause outside the useful band (adjacent channel). The system used for this linearization occupies a high percentage of the hardware and software resources of the telecommunication equipment, so it is interesting to minimize its complexity in order to make it as simple as possible. This paper analyzes the differences between the laterally diffused MOSFET (LDMOS) and gallium nitride (GaN) power amplifiers, in terms of their nonlinearity graphs, and in terms of the greater or lesser difficulty of linearization. A correct choice of power amplifier will allow for minimization of the linearization system, greatly simplifying the complexity of the final design.