Modulation Formats and Waveforms for 5G Networks: Who Will Be the Heir of OFDM?: An overview of alternative modulation schemes for improved spectral efficiency

TLDR

Fifth‑generation cellular networks aim to deliver gigabit data rates and up to a thousand‑fold capacity increase over LTE by employing innovative techniques across network layers, with the physical layer moving beyond OFDM to explore higher‑spectral‑efficiency alternatives. The article reviews 5G‑suitable modulation formats, comparing their cellular performance and discussing interactions with key 5G components. It examines these formats through comparative performance analysis and real‑channel measurements of their interaction with massive MIMO systems.

Abstract

Fifth-generation (5G) cellular communications promise to deliver the gigabit experience to mobile users, with a capacity increase of up to three orders of magnitude with respect to current long-term evolution (LTE) systems. There is widespread agreement that such an ambitious goal will be realized through a combination of innovative techniques involving different network layers. At the physical layer, the orthogonal frequency division multiplexing (OFDM) modulation format, along with its multiple-access strategy orthogonal frequency division multiple access (OFDMA), is not taken for granted, and several alternatives promising larger values of spectral efficiency are being considered. This article provides a review of some modulation formats suited for 5G, enriched by a comparative analysis of their performance in a cellular environment, and by a discussion on their interactions with specific 5G ingredients. The interaction with a massive multiple-input, multiple-output (MIMO) system is also discussed by employing real channel measurements.