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Przegląd metod wielodostępu nieortogonalnego i możliwości ich zastosowania w systemach 5G i 6G

Wesołowski Krzysztof

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2025

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nr 4

17--24

PL

W artykule dokonano przeglądu metod wielodostępu nieortogonalnego, w szczególności wielodostępu NOMA realizowanego w dziedzinie mocy. Po ogólnym podsumowaniu metod wielodostępu ortogonalnego OMA stosowanych w kolejnych generacjach komunikacji bezprzewodowej, wymieniono podstawowe metody wielodostępu NOMA w dziedzinie kodowej a następnie wyjaśniono zasadę działania systemu NOMA w dziedzinie mocy. Dokonano podstawowej analizy i porównania granicznej przepływności z wielodostępem OMA. Z kolei przedstawiono zaproponowane uprzednio przez autorów ulepszenie procesu kompensacji interferencji w łączu w górę systemu z wielodostępem NOMA w dziedzinie mocy. Następnie przeanalizowano podstawowe własności i zasady działania wielodostępu NOMA w przypadku transmisji wieloantenowej MISO i na podstawie literatury pokazano rozwiązania konkurencyjne, takie jak system wielu użytkowników z liniowym prekodowaniem (MU-LP) oraz system RSMA z rozdzielaniem transmitowanych wiadomości i częściową kompensacją interferencji. W podsumowaniu stwierdzono możliwość zastosowania wielodostępu NOMA w masowej transmisji między maszynami (IoT).

EN

The paper reviews non-orthogonal multiple access methods, in particular NOMA multiple access implemented in the power domain. After a general summary of orthogonal multiple access methods (OMA) used in subsequent generations of wireless communication, the basic NOMA multiple access methods in the code domain are listed, and then the operating principle of the NOMA system in the power domain is explained. Basic analysis and comparison of achievable rates with OMA multiple access are made. In turn, an improvement of the uplink interference compensation process of the system with NOMA in the power domain, previously proposed by the authors, is presented. Then, the basic properties and operating principles of the NOMA multiple access in the case of multi-antenna MISO transmission are analyzed and, based on the literature, competitive solutions are shown, such as the multi-user system with linear precoding (MU-LP) and the RSMA system with rate splitting and partial interference compensation. The paper ends with the conclusion about the possibility of using NOMA multiple access in massive machine-to-machine (IoT) communication.

2

UAV-BS-based Hybrid OMA-NOMA System with Multiple Antennas for Multi-user Communication

Sadeeq Ameer Y., Ahmed Mohamad A.

Journal of Telecommunications and Information Technology

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2025

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nr 2

28--45

EN

In this paper, an unmanned aerial vehicle (UAV) using hybrid orthogonal multiple access (OMA) and nonorthogonal multiple access (NOMA) solutions aided by multiple input multiple output (MIMO) technology is proposed to provide wireless communication for ground users (GUs). The proposed OMA-NOMA-MIMO system aims to improve throughput and spectrum efficiency. Additionally, it also strives to maximize the sum rate while achieving good user fairness. UAVs are considered as base stations (BSs) that provide services to users in multiple real-life scenarios, e.g. during natural disasters. They also enable aerial surveillance and help establish BSs during mass events. A pairing algorithm is proposed for far-near NOMAusers with an optimized power allocation (PA) mechanism to improve the performance of NOMA-UAV-BS. Channels between UAV-BS and GU are established as being of the line-of-sight (LoS) and non-line-of-sight (NLoS) varieties, taking into consideration the angle of departure (AoD) and the angle of arrival (AoA). The results obtained demonstrate that NOMA performs best in specific scenarios, while OMA overcomes NOMA in others. The outcomes of the project may be utilized to control the transmission performed by the UAV-BS by serving the GUs depending on the required quality of service.

3

Analysis of an LSTM-based NOMA Detector Over Time Selective Nakagami-m Fading Channel Conditions

Shankar Ravi, Bangare Jyoti L., Kumar Ajay, Gupta Sandeep, Mehraj Haider, Kulkarni Shriram S.

Journal of Telecommunications and Information Technology

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2022

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nr 3

17--24

EN

This work examines the efficacy of deep learning (DL) based non-orthogonal multiple access (NOMA) receivers in vehicular communications (VC). Analytical formulations for the outage probability (OP), symbol error rate (SER), and ergodic sum rate for the researched vehicle networks are established Rusing i.i.d. Nakagami-m fading links. Standard receivers, such as least square (LS) and minimum mean square error (MMSE), are outperformed by the stacked long-short term memory (S-LSTM) based DL-NOMA receiver. Under real time propagation circumstances, including the cyclic prefix (CP) and clipping distortion, the simulation curves compare the performance of MMSE and LS receivers with that of the DL-NOMA receiver. According to numerical statistics, NOMA outperforms conventional orthogonal multiple access (OMA) by roughly 20% and has a high sum rate when considering i.i.d. fading links.

4

An Approximate Evaluation of BER Performance for Downlink GSVD-NOMA with Joint Maximum-likelihood Detector

Hai Ngo Thanh, Khoa Dang Le

Journal of Telecommunications and Information Technology

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2022

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nr 3

25--37

EN

Generalized Singular Value Decomposition (GSVD) is the enabling linear precoding scheme for multiple-input multiple-output (MIMO) non-orthogonal multiple access (NOMA) systems. In this paper, we extend research concerning downlink MIMO-NOMA systems with GSVD to cover bit terror rate (BER) performance and to derive an approximate evaluation of the average BER performance. Specifically, we deploy, AT the base station, the well-known technique of joint-modulation to generate NOMAsymbols and joint maximum-likelihood (ML) to recover the transmitted data at end user locations. Consequently, the joint ML detector offers almost the same performance, In terms of average BER as ideal successive interference cancellation. Next, we also investigate BER performance of other precoding schemes, such as zero-forcing, block diagonalization, and simultaneous triangularization, comparing them with GSVD. Furthermore, BER performance is verified in different configurations in relation to the number of antennas. In cases where the number of transmit antennas is greater than twice the number of receive antennas, average BER performance is superior.

5

Sieci radiokomunikacyjne piątej generacji (5G) i ich znaczenie dla krajowego sektora elektroenergetycznego

Świderski Jacek

Wiadomości Elektrotechniczne

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2020

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R. 88, nr 1

20--24

PL

W artykule przedstawiono architekturę komórkowych sieci radiokomunikacyjnych piątej generacji (5G) oraz dokonano przeglądu nowych rozwiązań, które znajdą zastosowanie w tych sieciach. Omówiono strategię wdrożenia sieci 5G w Polsce, a także sformułowano uwagi na temat koncepcji ogólnokrajowej cyfrowej sieci radiokomunikacyjnej na potrzeby sektora elektroenergetycznego i potencjalnych możliwości wykorzystania do tego celu infrastruktury przyszłej sieci 5G.

EN

The article presents the architecture of fifth generation (5G) cellular networks and then a survey of new technologies which will be applied in their design. The strategy for implementing 5G networks in Poland is discussed, and comments on the concept of a nationwide digital wireless communication network for the needs of Polish power sector and potential possibilities of using the infrastructure of the future 5G network for this purpose is given.

6

Full-duplex Cognitive Radio NOMA Networks : Outage and Throughput Performance Analysis

Tran Thanh-Nam, Do Dinh-Thuan, Voznak Miroslav

International Journal of Electronics and Telecommunications

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2019

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Vol. 65, No. 1

103--109

EN

A novel non-orthogonal multiple access (NOMA) scheme is proposed to improve the throughput and the outage probability of the cognitive radio (CR) inspired system which has been implemented to adapt multiple services in the next-generation network (5G). In the proposed scheme, the primary source (PS) had sent a superposition code symbol with a predefined power allocation to relays, it decoded and forwarded (DF) a new superposition coded symbol to the destination with the other power allocation. By using a dual antenna at relays, it will be improved the bandwidth efficiency in such CR NOMA scheme. The performance of the system is evaluated based on the outage probability and the throughput with the assumption of the Rayleigh fading channels. According to the results obtained, it is shown that the outage probability and throughput of the proposed full-duplex (FD) in CR-NOMA with reasonable parameters can be able deploy in practical design as illustration in numerical results section.

7

Uplink NOMA Scheme for Wi-Fi Applications

Ghazi H. S., Wesołowski K.

International Journal of Electronics and Telecommunications

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2018

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Vol. 64, No. 4

481--485

EN

Non-Orthogonal Multiple Access (NOMA) with Successive Interference Cancellation (SIC) is one of the promising techniques proposed for 5G systems. It allows multiple users with different channel coefficients to share the same (time/frequency) resources by allocating several levels of (power/code) to them. In this article, a design of a cooperative scheme for the uplink NOMA Wi-Fi transmission (according to IEEE 802.11 standards) is investigated. Various channel models are exploited to examine the system throughput. Convolutional coding in conformance to IEEE 802.11a/g is applied to evaluate the system performance. The simulation results have been addressed to give a clear picture of the performance of the investigated system.