Digital Predistortion for Nonlinear PA in Filter Bank Multicarrier Systems

The adoption of orthogonal frequency division multiplexing (OFDM) technique has dominated the wired and wireless standards. This choice is due to several worthy OFDM's assets like its simplicity of implementation and its straightforward equalization. However, when more complex networks are considered, OFDM has to face many challenges. In these cases, it is necessary to use new waveforms with an enhanced spectral localization to replace OFDM. To this end, Filter bank multiple carrier waveform (FBMC) was proposed. However, the high peak to average power ratio (PAPR) of FBMC offset quadrature amplitude modulation (FBMC-OQAM) systems leads to a significant distortion when passed through a nonlinear device like high power amplifier (HPA). This one is considered as a major drawback of the RF front end stage. To cope with this, many techniques have been proposed such as analog predistortion (APD) and digital predistortion (DPD). These are generally tested for OFDM system. This article addresses the problem of the compensation of HPA distortions using digital predistortion in the case of FBMC-OQAM system.