Periodic OFDMA: A Low-PAPR Multiple Access Scheme for Uplink Communications in 5G and Beyond

TL;DR

This paper introduces P-OFDMA, a low-PAPR, energy-efficient multiple access scheme for uplink 5G communications, outperforming existing methods in power efficiency and complexity reduction.

Contribution

The paper proposes P-OFDMA and its variants, reducing PAPR and transmitter complexity while enhancing energy efficiency in uplink 5G systems.

Findings

P-OFDMA-DFT achieves the lowest PAPR among tested schemes.

P-OFDMA outperforms SC-FDMA in PAPR for low subcarrier-per-user scenarios.

Reduces transmitter processing by up to eight times compared to SC-FDMA.

Abstract

Multiple access techniques are vital for 5G and beyond. While Orthogonal Frequency Division Multiple Access (OFDMA) is standard, its high peak-to-average power ratio (PAPR) reduces energy efficiency in uplink transmissions. This paper presents Periodic OFDMA (P-OFDMA), a novel multiple access scheme with reduced PAPR and computational complexity. By assigning subcarriers in a periodic pattern across the entire frequency band, P-OFDMA enhances frequency diversity and simplifies allocation. We also introduce two precoded variants: P-OFDMA-DCT and P-OFDMA-DFT. Comprehensive simulations comparing P-OFDMA with OFDMA and SC-FDMA show that P-OFDMA-DFT consistently achieves the lowest PAPR. Furthermore, the standard P-OFDMA scheme outperforms SC-FDMA in PAPR for low subcarrier-per-user scenarios and achieves better bit error rate (BER) performance under high delay-spread conditions. Notably, P-OFDMA and its variants reduce transmitter-side processing by up to an eightfold factor compared to SC-FDMA, greatly benefiting low-complexity uplink devices. Although receiver complexity increases, the overall system processing load decreases, yielding improved energy efficiency. Thus, P-OFDMA offers a robust, energy-efficient uplink solution for future wireless networks.