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1

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

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2022

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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.

2

Performance Analysis of Filtered OFDM Based Downlink and Uplink NOMA System over Nakagami-m Fading Channel

Mukhtar Shaika, Begh Gh. Rasool

Journal of Telecommunications and Information Technology

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2021

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nr 2

11--23

EN

Efficient consumption of available resources and fulfillment of increasing demands are the two main challenges which are addressed by exploring advanced multiple access schemes along with efficient modulation techniques. To this end, non-orthogonal multiple access (NOMA) is discussed as a promising scheme for future 5G traffic. NOMA enables the users to share same resource block, permitting certain level of interference. In this paper, we propose filtered OFDM (F-OFDM) as a transmission waveform for NOMA systems, as it offers all the advantages of OFDM with the additional provision of sub-band filtering to satisfy the diverse services of the users. We examine F-OFDM in both downlink and uplink NOMA systems. Error-related performances of both downlink and uplink F-OFDM NOMA systems are analyzed and compared with conventional OFDM NOMA system over Nakagami-m fading channel. The results show that the error performance of F-OFDM NOMA is better than that of OFDM NOMA. An improvement of about 2 dB and 1 dB in bit error rate is achieved in downlink and uplink F-OFDM NOMA, respectively. Monte Carlo simulations are conducted for different values of fading parameter m, supporting the obtained analytical results.

3

Cooperative MIMO OFDM system based on Amplify and Forward Relay: Evaluation of ZF-SIC and MMSE-SIC equalization

Rahman M., Alam S., Islam S., Samy A. A., Islam N. A.

Przegląd Elektrotechniczny

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2018

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R. 94, nr 9

75--79

EN

In the world of wireless communication, cooperative communication is a modern and unprecedented approach which enables wireless nodes to transfer the information in a cooperative manner and finally to reach the destination without least possible deterioration. Orthogonal frequency division multiplexing (OFDM) can provide high data rate and better performance and a combination of OFDM and cooperative communication may push a wireless network forward to its next generation with enhanced reliability and efficiency. In this work, we develop a mathematical model for cooperative multiple input multiple output (MIMO) OFDM system. Results are achieved in the study to evaluate and compare bit error rate (BER) for different detection schemes. Based on the results it can be mentioned that the performance of cooperative MIMO-OFDM with space time block code (STBC) under amplify and forward (AF) relay for the MMSE-SIC detection scheme was found very satisfactory with improved signal to noise ratio (SNR).

PL

W artykule przedstawiono model matematyczny kooperacyjnej komunikacji bezprzewodowej wiele wejść, wiele wyjść (MIMO) z multipleksingiem i ortogonalnym podziałem częstotliwości (OFDM). Określono współczynnik BER (bit error rate) dla różnych metod detekcji. Najlepsze parametry otrzymano dla systemu STBC (space time block code).

4

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.

5

Iteracyjne sukcesywne usuwanie interferencji międzykanatowych w systemach OFDM

Kotrys R., Krasicki M., Remlein P., Stelter A., Szulakiewicz P.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2013

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nr 2-3

43--47

PL

Przedstawiono zastosowanie iteracyjnej metody sukcesywnego usuwania interferencji (SIC - Succesive Interference Cancellafion) do usuwania interferencji międzykanałowych w przypadku sygnałów OFDM. Omówiono znane z literatury przykłady jej wykorzystania, m.in. w systemach CDMA i OFDMA. Zaprezentowano iteracyjną wersję metody SIC (ISIC) w zastosowaniu do usuwania ACI z dwóch sąsiednich kanałów OFDM. Zademonstrowano przykład potencjalnego użycia metody ISIC w odbiorniku systemu WLAN, pokazano jak - dzięki proponowanej metodzie ISIC - można efektywnie korzystać z widma telekomunikacyjnego w systemach bezprzewodowych.

EN

In this paper an iterative successive interference cancellation (ISIC) method fa removing adjacent channel interference (ACI) from OFDM signals is developed. Prior to that, the genuine (non-iterative) SIC and its applications for CDMA and OFDMA systems are briefly reviewed. Results of a simulation experiment show that it is possible to exploit the telecommunication bandwidth in a more efficient way by incorporating ISIC block into WLAN (Wireless Local Area Network) 802.11ac receivers.