Title: Multi-user non-orthogonal waveform transceiver in RIS-assisted UAV communication: design and implementation

Authors: Md. Omor Faruk; Saifur Rahman Sabuj; S.K. Tamanna Kamal; Fowzia Jabin; Joarder Jafor Sadique; Shaikh Enayet Ullah

Addresses: Department of Electrical and Electronic Engineering, University of Rajshahi, Rajshahi, Bangladesh ' Department of Electrical and Electronic Engineering, Brac University, Dhaka, Bangladesh ' Department of Electrical and Electronic Engineering, University of Rajshahi, Rajshahi, Bangladesh ' Department of Electrical and Electronic Engineering, University of Rajshahi, Rajshahi, Bangladesh ' Department of Electrical and Electronic Engineering, Begum Rokeya University, Rangpur, Bangladesh ' Department of Electrical and Electronic Engineering, University of Rajshahi, Rajshahi, Bangladesh

Abstract: Reconfigurable Intelligent Surface (RIS) has evolved as an energy-efficient wireless communication technology and its anticipation with Unmanned Aerial Vehicles (UAV) has extended the millimetre wave range communications by enhancing wireless coverage. In this research article, we propose a downlink multi-user RIS-assisted Non-Orthogonal Waveform (NOW) transceiver system that is energy-efficient. A NOW approach for increasing spectrum efficiency through the integration of Faster-Than-Nyquist (FTN) signalling in DFT-s-OFDM is provided. In addition, we have implemented QR-GSO pre-coding algorithm for reducing Multi-User Interference (MUI). The simulated system incorporates Low-Density Parity Check (LDPC) and Repeats and Accumulates (RA) channel coding schemes along with various types of signal detection techniques such as Zero Forcing (ZF), Cholesky Decomposition (CD)-based ZF, Lattice Reduction-based MMSE (LR-MMSE) and Minimum Mean Square Error (MMSE) to improve Bit Error Rate (BER). Results from simulations demonstrate that the suggested system is effective with regard to of BER, energy efficiency and attainable spectral efficiency. The ground users achieve an improved BER performance with a value of 1 × 10⁻⁴ at 10 dB signal-to-noise ratio under RA with CD based ZF, 8 dB under RA with CD-based ZF, 10 dB under RA with LR-MMSE and 12 dB under RA with ZF.

Keywords: energy efficiency; faster-than-Nyquist signalling; millimetre-wave; non-orthogonal waveform; QR-GSO pre-coding; reconfigurable intelligent surfaces; unmanned aerial vehicle.

DOI: 10.1504/IJVICS.2025.144103

International Journal of Vehicle Information and Communication Systems, 2025 Vol.10 No.1, pp.85 - 111

Received: 14 Nov 2023
Accepted: 15 Aug 2024
Published online: 27 Jan 2025 *