HPA Rapp Model Nonlinear Distortion Effect Mitigation Technique on GFDM System

Abstract

Nowadays, smartphones have become a necessity for everyone. The internet is not only used by humans but is also used by various machines and equipment. This has resulted in new requirements for mobility, data rate, latency, quality of service, and high energy efficiency. Generalized Frequency Division Multiplexing (GFDM) is a non-orthogonal multicarrier transmission system that can overcome the shortcomings of Orthogonal Frequency Division Multiplexing (OFDM). Out-of-band (OOB) radiation in GFDM is controlled by a pulse shaping filter on each sub carrier. GFDM uses Cyclic Prefix (CP) to overcome the Interference Inter Symbol (ISI) on multipath channels. GFDM uses a better spectrum than OFDM because of its simpler structure. The contribution of this research is to apply mitigation techniques to overcome the effects of nonlinear distortion due to the use of the High Power Amplifier (HPA) Rapp Model on the GFDM system. The simulation results show that the application of a predistorter in GFDM can reduce the effect of HPA's nonlinear distortion. The system with the predictor was proven to have better spectrum parameters. The signal spectrum with HPA has an increase in OOB of 55 dB. Meanwhile, the predistorter system experienced a decrease in the OOB value of 55 dB, thus successfully compensating for the HPA effect. A system with a predistorter to obtain a Bit Error Rate (BER) of 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> requires an E <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">b</inf> /N <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</inf> of 9 dB.