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1
Content available Reliable 5G waveform detection from an optical fibre transmitter system
Yaseen Zeyad T., Algriree Waleed
Opto-Electronics Review
|
2024
|
Vol. 32, No. 1
art. no. e149181
EN
The integration of optical fibre communication with multiple input multiple output-non-orthogonal multiple access (MIMO-NOMA) waveforms in cognitive radio (CR) systems is examined in this study. The proposed system leverages the advantages of optical fibre, including high bandwidth and immunity to electromagnetic interference to facilitate the transmission and reception of MIMO-NOMA signals in a CR environment. Moreover, MIMO-NOMA signal was detected and analysed by the hybrid-discrete cosine transform-Welch (H-DCT-W) method. Based on the modes results, a detection probability greater than 0.96%, a false alarm probability equal to 0.06, and a global system error probability equal to 0.09% were obtained with a signal-to-noise ratio (SNR) less than 0 dB, while maintaining a simple level of complexity. The results obtained in this paper indicate the potential of the optical fibre-based MIMO-NOMA system based on H-DCT-W technology in CR networks. Therefore, its suitability for practical CR applications is demonstrated by the improvements obtained in false alarms, detection probability, and error rates at low levels of SNR. This study contributes to the development of efficient and reliable wireless communication systems by linking cooperation and synergy concerning MIMO-NOMA, optical fibres, as well as the proposed detection technique (H-DCT-W).
2
Content available remote Non orthogonal multiple access verses orthogonal multiple access performance comparison in 5G communication system
Ahmad Bushra Muhammed, Mahmood Farhad E., Alsawaf Hiba A.
Przegląd Elektrotechniczny
|
2023
|
R. 99, nr 1
129--133
EN
The current generation of mobile networks requires speeding up the steps to meet the future demand for high data rates, and low latency. In 5G, the Third Generation Partnership Project (3GPP) is working to support numerous users and high spectral efficiency via different technologies, such as the Non-Orthogonal Multiple Access (NOMA) scheme. This paper provides a study of NOMA and how NOMA addresses the 5G requirements, ongoing standardization efforts for NOMA, and a comparative study of NOMA with other OMA schemes like orthogonal frequency division multiple access (OFDMA). The results show improved user productivity in NOMA compared to OFDMA. We also proposed a new technique called the multi-tier hybrid NOMAOMA to get the robustness of OMA and the flexibility of NOMA to increase the spectrum efficiency and the number of users. The multi-tier facilitates the user such that to reduce the interference. We also study the impact of several tiers on the capacity, the result shows that five tiers provide the best capacity in multi-tier hybrid NOMAOMA.
PL
Obecna generacja sieci komórkowych wymaga przyspieszenia kroków w celu zaspokojenia przyszłego zapotrzebowania na dużą szybkość transmisji danych i niskie opóźnienia. W ramach 5G, Projekt Partnerstwa Trzeciej Generacji (3GPP) pracuje nad wsparciem wielu użytkowników i wysokiej wydajności widmowej za pomocą różnych technologii, takich jak schemat nieortogonalnego dostępu wielokrotnego (NOMA). Ten artykuł zawiera analizę NOMA i sposobu, w jaki NOMA spełnia wymagania 5G, trwające wysiłki normalizacyjne dla NOMA oraz badanie porównawcze NOMA z innymi schematami OMA, takimi jak wielokrotny dostęp z ortogonalnym podziałem częstotliwości (OFDMA). Wyniki pokazują lepszą produktywność użytkownika w NOMA w porównaniu z OFDMA. Zaproponowaliśmy również nową technikę zwaną wielowarstwową hybrydową NOMAOMA, aby uzyskać solidność OMA i elastyczność NOMA w celu zwiększenia wydajności widma i liczby użytkowników. Wielopoziomowy ułatwia użytkownikowi tak, aby zmniejszyć zakłócenia. Badamy również wpływ kilku warstw na pojemność, wynik pokazuje, że pięć warstw zapewnia najlepszą pojemność w wielowarstwowej hybrydowej NOMAOMA.
3
Content available Performance Enhancement of Cooperative MIMO-NOMA Systems Over Sub-6 GHz and mmWave Bands
Saleh Ahmed A., Ahmed Mohamad A.
Journal of Telecommunications and Information Technology
|
2023
|
nr 2
70--77
EN
In this paper, two radio links with different frequency bands are considered for base stations (BS) serving users via decode-and-forward (DF) cooperative relays. Backhaul and access links are proposed with sub-6 GHz and millimeter wave (mmWave) bands, respectively. Non-orthogonal multiple access (NOMA) is employed in the backhaul link to simultaneously transmit a superposed signal in the power domain, using the same band. The superposed signals, containing two signals that differ in terms of power allocation factors (PAFs), are designed for two selected DF relays in the BS. The two relays are chosen from several relays to be serviced by the BS based on a pairing algorithm that depends on different users’ circumstances. The furthest DF relay detects the incoming NOMA signal directly, while the nearest one applies successive interference cancellation (SIC) before extracting its signal. Each DF relay forwards the detected signals toward their intended users over mmWave channels. Three performance metrics are utilized to evaluate the system’s performance: outage probability, achievable throughput, and bit error rate. Comparisons between two mmWave bands in the access link (28 and 73 GHz) are made to demonstrate the superiority of the 28 GHz band in terms of the three performance-related metrics.
4
Content available Zipf Distribution Power AllocationAapproach for NOMA Systems
Himeur Hanane, Meriah Sidi Mohammed, Derraz Fouad
International Journal of Electronics and Telecommunications
|
2023
|
Vol. 69, No. 3
559--564
EN
Non-orthogonal multiple access (NOMA) has received tremendous attention for the development of 5G and beyond wireless networks. Power-domain NOMA works on the concept of assigning varying power levels to users within the same frequency and time block. In this paper we propose a novel power allocation approach that uses the Zipf distribution law that satisfies the basic condition of a NOMA system. The Zipf PA is characterized by the simplicity and ease of implementation that allows to extend the capacity of the system to support a large number of users. The numerical results show that the system achieves high throughput and energy efficiency without any parameter optimization constraints as well as improved capacity by increasing the number of users compared to the NOMA system with existing power allocation techniques.
5
Content available Investigation of Vehicular S-LSTM NOMA Over Time Selective Nakagami-m Fading with Imperfect CSI
Shankar Ravi, Chaudhary Bhanu Pratap, Mishra Ritesh Kumar
Journal of Telecommunications and Information Technology
|
2022
|
nr 4
47--59
EN
In this paper, the performance of a deep learningbased multiple-input multiple-output (MIMO) non-orthogonal multiple access (NOMA) system is investigated for 5G radio communication networks. We consider independent and identically distributed (i.i.d.) Nakagami-m fading links to prove that when using MIMO with the NOMA system, the outage probability (OP) and end-to-end symbol error rate (SER) improve, even in the presence of imperfect channel state information (CSI) and successive interference cancellation (SIC) errors. Furthermore, the stacked long short-term memory (S-LSTM) algorithm is employed to improve the system’s performance, even under time-selective channel conditions and in the presence of terminal’s mobility. For vehicular NOMA networks, OP, SER, and ergodic sum rate have been formulated. Simulations show that an S-LSTM-based DL-NOMA receiver outperforms least square (LS) and minimum mean square error (MMSE) receivers. Furthermore, it has been discovered that the performance of the end-to-end system degrades with the growing amount of node mobility, or if CSI knowledge remains poor. Simulated curves are in close agreement with the analytical results.
6
Content available 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
|
2022
|
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.
7
Content available 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
|
2022
|
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.
8
Content available The Performance Evaluation of NOMA for 5G Systems Using Automatic Deployment of Multi Users
Suprith P. G., Mohammed Riyaz Ahmed
International Journal of Electronics and Telecommunications
|
2022
|
Vol. 68, No. 2
337--342
EN
Non-Orthogonal Multiple Access (NOMA) in the fifth generation (5G) system is one of the optimistic technologies for wireless radio access networks. Compared to orthogonal multiple accesses (OMA) reduce the spectral efficiency; NOMA provides the best solution by increasing the data rates. This study evaluates NOMA with a downlink in the automatic deployment of multiusers. The outage performance and ergotic sum-rate gain give the NOMA better performance can be concluded at the final results. NOMA provides the Quality of Service (QoS) to the multi-users by considering the power allocation and data rate factors. Here is considered the outage probability will be 1 when it identifies the different user and allocates the data rate and power.
9
Content available Enabling Power Beacons and Wireless Power Transfers for Non-Orthogonal Multiple Access Networks
Le Chi-Bao, Nguyen Nhan Duc
Journal of Telecommunications and Information Technology
|
2021
|
nr 3
1--9
EN
This paper studies downlink cellular networks relying on non-orthogonal multiple access (NOMA). Specifically, the access point (AP) is able to harvest wireless power from the power beacon (PB). In the context of an AP facilitated with multiple antennas, the transmit antenna selection procedure is performed to process the downlink signal, with the transmission guaranteed by energy harvesting. Therefore, a wireless power transfer-based network is introduced to overcome power outages at the AP. In particular, an energy-constrained AP harvests energy from the radio frequency signals transmitted by the PB in order to assist in transmitting user data. Outage performance and ergodic capacity are evaluated with the use of closed-form expressions. In order to highlight some insights, approximate computations are provided. Finally, numerical simulations are performed to confirm the benefits of combining the downlink NOMA transmission and the transmit power scheme at the AP in order to serve a multitude of users.
10
Content available Selected aspects of non-orthogonal multiple access for future wireless communications – for IoT
Wysocki Tadeusz A., Flizikowski Adam, Marciniak Tomasz
Zeszyty Naukowe. Telekomunikacja i Elektronika / Uniwersytet Technologiczno-Przyrodniczy w Bydgoszczy
|
2020
|
nr 24
45--65
EN
This paper has provided an overview of selected IoT architectures, relevant requirements towards 5G (and beyond) systems as well as indication of NOMA techniques suitability as a multiple access technique and recent developments in the area of radio interface for IoT coexisting with 5G (and beyond) mobile networks. The authors assume that IoT networks in the future will be augmented with NOMA-capable sink-nodes (proxy or gateway) that can deliver aggregated data from multiple sensors for delivery to the cloud or other server. The main aim of this paper is to go beyond state of the art available nowadays and indicate directions for NOMA that make it even more attractive in combination with edge computing, cloud-RAN and especially AI/ML to improve future 6G networks.
11
Sieci radiokomunikacyjne piątej generacji (5G) i ich znaczenie dla krajowego sektora elektroenergetycznego
Świderski Jacek
Wiadomości Elektrotechniczne
|
2020
|
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.
12
Content available 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
|
2019
|
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.
13
Content available Uplink NOMA Scheme for Wi-Fi Applications
Ghazi H. S., Wesołowski K.
International Journal of Electronics and Telecommunications
|
2018
|
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.
14
Nieortogonalna metoda dostępu wielokrotnego dla systemów następnych generacji
Gajewska M.
Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne
|
2017
|
nr 6
202--2015, CD
PL
W artykule zaprezentowano nieortogonalną, metodę dostępu wielokrotnego do kanału, nazywaną w skrócie metodą NOMA, która jest prawdopodobna do zastosowania w systemach 5G. Porównano ją z dotychczas powszechnie stosowanymi metodami ortogonalnymi OMA. Analizę przeprowadzono dla łącza w dół i łącza w górę.
EN
In the article a non-orthogonal multiple access method called NOMA is presented. This method is planned for use in 5G systems. The NOMA is compared with groups orthogonal methods named OMA which are currently used. This analysis was performed both for downlink and uplink.
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