Kinzah Noor¹, Agbotiname Lucky Imoize^2,*, Michael Adedosu Adelabu³, Cheng-Chi Lee^4,5,*

CMES-Computer Modeling in Engineering & Sciences, Vol.145, No.2, pp. 1575-1664, 2025, DOI:10.32604/cmes.2025.073200 - 26 November 2025

Abstract The envisioned 6G wireless networks demand advanced Multiple Access (MA) schemes capable of supporting ultra-low latency, massive connectivity, high spectral efficiency, and energy efficiency (EE), especially as the current 5G networks have not achieved the promised 5G goals, including the projected 2000 times EE improvement over the legacy 4G Long Term Evolution (LTE) networks. This paper provides a comprehensive survey of Artificial Intelligence (AI)-enabled MA techniques, emphasizing their roles in Spectrum Sensing (SS), Dynamic Resource Allocation (DRA), user scheduling, interference mitigation, and protocol adaptation. In particular, we systematically analyze the progression of traditional and modern… More > Graphic Abstract

Phu Tran Tin¹, Minh-Sang Van Nguyen², Quy-Anh Bui¹, Agbotiname Lucky Imoize³, Byung-Seo Kim^4,*

CMES-Computer Modeling in Engineering & Sciences, Vol.144, No.2, pp. 2521-2543, 2025, DOI:10.32604/cmes.2025.066669 - 31 August 2025

Abstract Digital content such as games, extended reality (XR), and movies has been widely and easily distributed over wireless networks. As a result, unauthorized access, copyright infringement by third parties or eavesdroppers, and cyberattacks over these networks have become pressing concerns. Therefore, protecting copyrighted content and preventing illegal distribution in wireless communications has garnered significant attention. The Intelligent Reflecting Surface (IRS) is regarded as a promising technology for future wireless and mobile networks due to its ability to reconfigure the radio propagation environment. This study investigates the security performance of an uplink Non-Orthogonal Multiple Access (NOMA)… More >

Ru Hao^1,2,3, Chi Xu^2,3,*, Jing Liu¹

CMC-Computers, Materials & Continua, Vol.82, No.2, pp. 3203-3222, 2025, DOI:10.32604/cmc.2024.059689 - 17 February 2025

Abstract Non-orthogonal multiple access (NOMA) technology has recently been widely integrated into multi-access edge computing (MEC) to support task offloading in industrial wireless networks (IWNs) with limited radio resources. This paper minimizes the system overhead regarding task processing delay and energy consumption for the IWN with hybrid NOMA and orthogonal multiple access (OMA) schemes. Specifically, we formulate the system overhead minimization (SOM) problem by considering the limited computation and communication resources and NOMA efficiency. To solve the complex mixed-integer nonconvex problem, we combine the multi-agent twin delayed deep deterministic policy gradient (MATD3) and convex optimization, namely More >

Hailing Yang¹, Suoping Li^1,2,*, Duo Peng²

CMC-Computers, Materials & Continua, Vol.79, No.3, pp. 5273-5294, 2024, DOI:10.32604/cmc.2024.050869 - 20 June 2024

Abstract To address the problems of network congestion and spectrum resources shortage in multi-user large-scale scenarios, this paper proposes a twice random access OFDMA-NOMA-RA protocol combining the advantages of orthogonal frequency division multiple access (OFDMA) and non-orthogonal multiple access (NOMA). The idea of this protocol is that OFMDA is used to divide the entire frequency field into multiple orthogonal resource units (RUs), and NOMA is used on each RU to enable more users to access the channel and improve spectrum efficiency. Based on the protocol designed in this paper, in the case of imperfect successive interference… More >

Lassaad K. Smirani¹, Leila Jamel^2,*, Latifah Almuqren²

CMES-Computer Modeling in Engineering & Sciences, Vol.140, No.2, pp. 1315-1337, 2024, DOI:10.32604/cmes.2024.047551 - 20 May 2024

Abstract This study presents a layered generalization ensemble model for next generation radio mobiles, focusing on supervised channel estimation approaches. Channel estimation typically involves the insertion of pilot symbols with a well-balanced rhythm and suitable layout. The model, called Stacked Generalization for Channel Estimation (SGCE), aims to enhance channel estimation performance by eliminating pilot insertion and improving throughput. The SGCE model incorporates six machine learning methods: random forest (RF), gradient boosting machine (GB), light gradient boosting machine (LGBM), support vector regression (SVR), extremely randomized tree (ERT), and extreme gradient boosting (XGB). By generating meta-data from five… More >

Zhiping Lu¹, Xinwei Yue^2,*, Shuo Chen², Weiguo Ma¹

CMES-Computer Modeling in Engineering & Sciences, Vol.137, No.1, pp. 789-812, 2023, DOI:10.32604/cmes.2023.027663 - 23 April 2023

Abstract Active intelligent reflecting surface (IRS) is a novel and promising technology that is able to overcome the multiplicative fading introduced by passive IRS. In this paper, we consider the application of active IRS to non-orthogonal multiple access (NOMA) networks, where the incident signals are amplified actively through integrating amplifier to reflecting elements. More specifically, the performance of active/passive IRS-NOMA networks is investigated over large and small-scale fading channels. Aiming to characterize the performance of active IRS-NOMA networks, the exact and asymptotic expressions of outage probability for a couple of users, i.e., near-end user and far-end… More >

Ziwei Liu¹, Xinwei Yue^1,*, Shuo Chen¹, Xuliang Liu², Yafei Wang¹, Wanwei Tang³

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.1, pp. 767-785, 2023, DOI:10.32604/cmes.2023.025300 - 05 January 2023

Abstract Hardware impairments (HI) are always present in low-cost wireless devices. This paper investigates the outage behaviors of intelligent reflecting surface (IRS) assisted non-orthogonal multiple access (NOMA) networks by taking into account the impact of HI. Specifically, we derive the approximate and asymptotic expressions of the outage probability for the IRS-NOMA-HI networks. Based on the asymptotic results, the diversity orders under perfect self-interference cancellation and imperfect self-interference cancellation scenarios are obtained to evaluate the performance of the considered network. In addition, the system throughput of IRS-NOMA-HI is discussed in delay-limited mode. The obtained results are provided More >

Yanqiu Chen, Xiaopeng Ji^*

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.1, pp. 531-553, 2023, DOI:10.32604/cmes.2023.024531 - 05 January 2023

Abstract Non-orthogonal multiple access technology (NOMA), as a potentially promising technology in the 5G/B5G era, suffers from ubiquitous security threats due to the broadcast nature of the wireless medium. In this paper, we focus on artificial-signal-assisted and relay-assisted secure downlink transmission schemes against external eavesdropping in the context of physical layer security, respectively. To characterize the non-cooperative confrontation around the secrecy rate between the legitimate communication party and the eavesdropper, their interactions are modeled as a two-person zero-sum game. The existence of the Nash equilibrium of the proposed game models is proved, and the pure strategy More >

Xianli Gong¹, Chongwen Huang^2,3,4, Xinwei Yue⁵, Zhaohui Yang^2,4,6, Feng Liu^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.135, No.3, pp. 2531-2555, 2023, DOI:10.32604/cmes.2023.024940 - 23 November 2022

Abstract In this paper, we consider a downlink non-orthogonal multiple access (NOMA) network assisted by two reconfigurable intelligent surfaces (RISs) over Rician fading channels, in which each user communicates with the base station by the virtue of a RIS to enhance the reliability of the received signal. To evaluate the system performance of our proposed RIS-NOMA network, we first derive the exact and asymptotic expressions for the outage probability and ergodic rate of two users. Then, we derive the exact and asymptotic upper bound expressions for the ergodic rate of the nearby user. Based on asymptotic… More >

Fahad R. Albogamy¹, M. A. Aiyashi², Fazirul Hisyam Hashim³, Imran Khan⁴, Bong Jun Choi^5,*

CMC-Computers, Materials & Continua, Vol.74, No.2, pp. 3249-3261, 2023, DOI:10.32604/cmc.2023.031673 - 31 October 2022

Abstract The non-orthogonal multiple access (NOMA) method is a novel multiple access technique that aims to increase spectral efficiency (SE) and accommodate enormous user accesses. Multi-user signals are superimposed and transmitted in the power domain at the transmitting end by actively implementing controllable interference information, and multi-user detection algorithms, such as successive interference cancellation (SIC), are performed at the receiving end to demodulate the necessary user signals. Although its basic signal waveform, like LTE baseline, could be based on orthogonal frequency division multiple access (OFDMA) or discrete Fourier transform (DFT)-spread OFDM, NOMA superimposes numerous users in… More >