Combined Polar Codes and 2-12 QAM Applied to 5G Communications

Abstract

The 5th generation of cellular communications systems (5G), standardized by the 3rd Generation Partnership Project (3GPP), uses polar codes in both physical download control channel (PDCCH) and physical download shared channel (PDSCH), combined with some low order modulations, such as QPSK and 16-QAM. Recently, 2-12-QAM modulation was proposed as an energy-efficient scheme when compared to 16-QAM. This article investigates the performance of a communication system using polar codes combined with a 2-12-QAM modulation scheme over channels disturbed by additive white Gaussian noise (AWGN) as well as over channels disturbed simultaneously by Rayleigh fading and AWGN. The 2-12-QAM modulation is compatible with legacy 16-QAM still widely used, and when combined with appropriate error correcting codes produces results that approach the Shannon limit.