Robust Modeling and Linearization of MIMO RF Power Amplifiers for 4G and 5G Applications

Abstract

In this paper, a novel set of orthogonal crossover polynomials for the baseband modelling and linearization of MIMO RF Pas is presented. The proposed solution is applicable to WCDMA and LTE applications. The new modelling approach has considerably reduced the numerical instability problem associated with the conventional polynomial model identification. In order to validate the efficiency and the robustness of the proposed solution, a 2x2 MIMO LDMOS RF power amplifier has been measured modelled and linearized. A comparison with the conventional polynomial MIMO models showed clearly the superiority of the proposed solution in a fixed-point calculation environment such as DSP and FPGA boards. Keywords-MIMO transmitter; RF power amplifiers; orthogonal polynomials; nonlinear transmitters; digital predistortionI.The organization of the paper is as follows. In Section. 2, we introduce the reference crossover conventional polynomials