RPDMA: A PAPR-Aware Multiple Access Scheme

January 1, 2026·
Goli Srikanth
,
Shaik Basheeruddin Shah
,
Nazar T. Ali
,
Vijay Kumar Chakka
,
Jorge Querol
,
Ahmed Altunaiji
,
Dragan I. Olćan
· 2 min read
Abstract
This paper proposes a novel Multiple Access (MA) scheme called Ramanujan Periodic subspace Division Multiple Access (RPDMA) for subcarrier sizes N = 2m, m ∊ N, to address the high Peak-to-Average Power Ratio (PAPR) in Orthogonal Frequency Division Multiple Access (OFDMA). Building on the properties of Ramanujan subspaces, we design transmitter and receiver models that allocate users on a subspace-wise basis, ensuring zero inter-user interference, providing inherent frequency diversity. We analyze the computational complexity of OFDMA, SC-FDMA, and RPDMA, and find that RPDMA has substantially lower per-user transmitter complexity than both OFDMA and SC-FDMA, while its receiver complexity is comparable to SC-FDMA and higher than that of OFDMA. We further introduce a generalized framework, termed Nested Periodic-subspace Division Multiple Access (NPDMA), which unifies both RPDMA and OFDMA under a common family of multi-carrier MA schemes. We derive the theoretical PAPR of RPDMA and demonstrate its superiority over OFDMA. The analysis is validated through numerical simulations under two multi-user scenarios with diverse Quality of Service (QoS) requirements. The results demonstrate that RPDMA achieves lower PAPR than both OFDMA and SC FDMA, with users assigned larger subspaces benefiting from even greater PAPR reduction. We prove that both the sum and per-user Spectral Efficiency (SE) of RPDMA are identical to those of OFDMA and SC-FDMA. In terms of Bit Error Rate (BER), SC-FDMA achieves the best performance, while RPDMA still outperforms OFDMA as the SNR increases.
Type
Publication
IEEE Open Journal of Vehicular Technology
publication

Abstract & Overview

This paper proposes a novel Multiple Access (MA) scheme called Ramanujan Periodic subspace Division Multiple Access (RPDMA) for subcarrier sizes N = 2m, m ∊ N, to address the high Peak-to-Average Power Ratio (PAPR) in Orthogonal Frequency Division Multiple Access (OFDMA). Building on the properties of Ramanujan subspaces, we design transmitter and receiver models that allocate users on a subspace-wise basis, ensuring zero inter-user interference, providing inherent frequency diversity. We analyze the computational complexity of OFDMA, SC-FDMA, and RPDMA, and find that RPDMA has substantially lower per-user transmitter complexity than both OFDMA and SC-FDMA, while its receiver complexity is comparable to SC-FDMA and higher than that of OFDMA. We further introduce a generalized framework, termed Nested Periodic-subspace Division Multiple Access (NPDMA), which unifies both RPDMA and OFDMA under a common family of multi-carrier MA schemes. We derive the theoretical PAPR of RPDMA and demonstrate its superiority over OFDMA. The analysis is validated through numerical simulations under two multi-user scenarios with diverse Quality of Service (QoS) requirements. The results demonstrate that RPDMA achieves lower PAPR than both OFDMA and SC FDMA, with users assigned larger subspaces benefiting from even greater PAPR reduction. We prove that both the sum and per-user Spectral Efficiency (SE) of RPDMA are identical to those of OFDMA and SC-FDMA. In terms of Bit Error Rate (BER), SC-FDMA achieves the best performance, while RPDMA still outperforms OFDMA as the SNR increases.


Publication Metadata

  • Authors: Goli Srikanth, Shaik Basheeruddin Shah, Nazar T. Ali, Vijay Kumar Chakka, Jorge Querol, Ahmed Altunaiji, Dragan I. Olćan
  • Venue: IEEE Open Journal of Vehicular Technology (2026)
  • Research Areas: Satellite Communications, Signal Processing
  • DOI: 10.1109/ojvt.2026.3661153
  • Open Access Repository: ORBiLu – University of Luxembourg