Efficient Compensation of the Nonlinearity of Solid-State Power Amplifiers Using Adaptive Sequential Monte Carlo Methods

Abstract

In this paper, the sequential Monte Carlo (SMC) framework is studied as a tool to compensate the nonlinear distortions caused by solid-state power amplifiers (SSPA) in M-QAM schemes. The performance of the SMC approach is shown for low- and high-order constellation schemes for different values of the input backoff (IBO). The results show that, in low-IBO regimes, the SMC method provides a significant improvement compared to conventional methods, such as the predistorter, especially for high-order constellations while the use of the predistorter is preferred in only a very limited number of cases. Moreover, the SMC framework is shown to have more robust behavior to the constellation scaling. The application of the SMC framework to multicarrier systems is also addressed and the behavior of the system in terms of the out-of-band emissions as a function of the output backoff (OBO) is investigated. Finally, an adaptive sequential Monte Carlo receiver is proposed that adapts itself efficiently to the variations in the amplifier parameters. This adaptive scheme does not require a training sequence and does not suffer from convergence problems.