scholarly journals MULTIPLE ACCESS TECHNIQUES FOR 5G NETWORKS

2020 ◽  
Vol 5 (2) ◽  
pp. 305-314
Author(s):  
Mrs. Rinkoo Bhatia
Keyword(s):  
Multiple Access ◽  
Heterogeneous Traffic ◽  
5G Networks ◽  
Comprehensive Overview ◽  
Fifth Generation ◽  
Power Domain ◽  
Different Types ◽  
Code Domain ◽  
Multiple Access Schemes ◽  
Multiple Domains

Fifth generation (5G) wireless networks face various challenges in order to support largescale heterogeneous traffic and users, therefore new modulation and multiple access (MA) schemes are being developed to meet the changing demands. As this research space is ever increasing, it becomes more important to analyze the various approaches, therefore, in this article we present a comprehensive overview of the most promising Multiple Access schemes for 5G networks. Our article focuses on various types of non-orthogonal multiple access (NOMA) techniques. Specifically, we first introduce different types of modulation schemes, potential for OMA. We then pay close attention to various types of NOMA candidates, including power-domain NOMA, code-domain NOMA, and NOMA multiplexing in multiple domains. From this exploration, we can identify the opportunities and challenges that will have the most significant impacts on modulation and MA designs for 5G networks.

scholarly journals Code Domain Non- Orthogonal Multiple Access Schemes for 5G and Beyond Communication Networks: A Review

2021 ◽  
Author(s):  
Aasheesh Shukla ◽  
◽  
Manish Kumar ◽  
Vinay Kumar Deolia ◽  
◽  
...  
Keyword(s):  
Communication Networks ◽  
Multiple Access ◽  
Heterogeneous Data ◽  
Data Traffic ◽  
5G Networks ◽  
Comprehensive Overview ◽  
Power Domain ◽  
Rate Splitting ◽  
Code Domain ◽  
Multiple Access Schemes

Future communication networks may encounter various issues in order to facilitate heavy heterogeneous data traffic and large number of users, therefore more advanced multiple access (MA) schemes are being developed to meet the changing requirements. The research space on making more robust MA scheme is continuously increasing, so it becomes significant to analyze the various schemes to determine the appropriate MA scheme for 5G networks. Therefore, in this paper the comprehensive overview of the most popular and recent MA schemes is presented for 5G networks. This paper mainly classifies the MA techniques in orthogonal MA (OMA) and various types of non-OMA (NOMA) techniques. Specifically, we introduce RSMA (Rate splitting multiple access) and IDMA (interleave division multiple access). Further the close attention is paid to NOMA family, including code-domain NOMA (e.g., SCMA (sparse code multiple access)), power-domain NOMA. Above all, from this exploration, the opportunities and challenges could be notified in MA schemes and further the optimum MA technique can be point out among discussed MA schemes for 5G and beyond communication networks.

Non-Orthogonal Multiple Access

2019 ◽  
Author(s):  
Sanjeev Gurugopinath
Keyword(s):  
Interference Cancellation ◽  
Communication Systems ◽  
Multiple Access ◽  
Future Research ◽  
Superposition Coding ◽  
Fifth Generation ◽  
Power Domain ◽  
Code Domain ◽  
5G Communication ◽  
Code Division Multiple

Non-orthogonal multiple access (NOMA) has been recently proposed as a technique to increase the network throughput and to support massive connectivity, which are major requirements in the fifth generation (5G) communication systems. The NOMA can be realized through two different approaches, namely, in (a) power-domain, and (b) code-domain. In the power-domain NOMA (PD-NOMA), multiple users are assigned different power levels – based on their individual channel quality information – over the same orthogonal resources. The functionality of PD-NOMA comprises of two main techniques, namely, superposition coding at the transmitter and successive interference cancellation (SIC) at the receiver. An efficient implementation of SIC would facilitate to remove interference across the users. The SIC is carried out at users with the best channel conditions and is performed in descending order of the channel. On the other hand, in the code-domain NOMA (CD-NOMA), multiplexing is carried out using low-density spreading sequences for each user, similar to the code division multiple access (CDMA) technology. In this article, we provide an introduction to NOMA and present the details on the working principle of NOMA systems. Later, we discuss the different types of NOMA schemes under PD- and CD-domains, and investigate the related applications in the context of 5G communication systems. Additionally, we discuss the integration of NOMA with other technologies related to 5G such as cognitive radio and massive MIMO, and discuss some future research challenges.

A Review of Power Domain Non-Orthogonal Multiple Access in 5G Networks

2018 ◽  
Vol 10 (7) ◽  
Author(s):  
Aiman Kassir ◽  
◽  
Rudzidatul Akmam Dziyauddin ◽  
Hazilah Mad Kaidi ◽  
Mohd Azri Mohd Izhar ◽  
...  
Keyword(s):  
Multiple Access ◽  
5G Networks ◽  
Power Domain

A survey and taxonomy on nonorthogonal multiple-access schemes for 5G networks

2017 ◽  
Vol 29 (1) ◽  
pp. e3202 ◽  
Author(s):  
Mehak Basharat ◽  
Waleed Ejaz ◽  
Muhammad Naeem ◽  
Asad Masood Khattak ◽  
Alagan Anpalagan
Keyword(s):  
Multiple Access ◽  
5G Networks ◽  
Multiple Access Schemes

scholarly journals NOMA for Multinumerology OFDM Systems

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Ayman T. Abusabah ◽  
Huseyin Arslan
Keyword(s):  
Orthogonal Frequency Division Multiplexing ◽  
Multiple Access ◽  
Frequency Division ◽  
Ofdm Systems ◽  
Superposition Coding ◽  
Promising Technique ◽  
Successive Interference Cancelation ◽  
Power Domain ◽  
Multiple Access Schemes ◽  
Spectrally Efficient

Nonorthogonal multiple access (NOMA) is a promising technique which outperforms the traditional multiple access schemes in many aspects. It uses superposition coding (SC) to share the available resources among the users and adopts successive interference cancelation (SIC) for multiuser detection (MUD). Detection is performed in power domain where fairness can be supported through appropriate power allocation. Since power domain NOMA utilizes SC at the transmitter and SIC at the receiver, users cannot achieve equal rates and experience higher interference. In this paper, a novel NOMA scheme is proposed for multinumerology orthogonal frequency division multiplexing system, that is, different subcarrier spacings. The scheme uses the nature of mixed numerology systems to reduce the constraints associated with the MUD operation. This scheme not only enhances the fairness among the users but improves the bit error rate performance as well. Although the proposed scheme is less spectrally efficient than conventional NOMA schemes, it is still more spectrally efficient than orthogonal multiple access schemes.

scholarly journals Effects of Power Allocation and User Mobility on Non-Orthogonal Multiple Access Using Successive Interference Cancellation

ELKHA ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 1
Author(s):  
Khoirun Niamah ◽  
Solichah Larasati ◽  
Raudhatul Jannah
Keyword(s):  
Power Allocation ◽  
High Power ◽  
Interference Cancellation ◽  
Multiple Access ◽  
Successive Interference Cancellation ◽  
Channel Gain ◽  
User Mobility ◽  
Power Domain ◽  
Code Domain

This research based on simulation to show impact of the power allocation on Non-Orthogonal Multiple Access (NOMA) using Successive Interference Cancellation (SIC). NOMA used superposition code (SC) on the transmitter and SIC on the receiver. NOMA has two categories power domain (PD) and code domain (CD). This research based on PD-NOMA simulated for downlink. The number of users who use the same recourse block are divided into two conditions: user with apply SIC and without SIC base on the value of channel gain from each user. Applying SC on the transmitter and SIC on the receiver will cancel of interference. Novelties of this research are the best performance of power allocation and user mobility based on parameter BER and SNR. Allocation of the power transmit based on value of channel gain every user, where user with value of channel gain is low will be allocated high power transmit, and otherwise. The best result performance of BER vs SNR used ratio power transmit 0.45 dB:0.55 dB, BER  get value SNR for 17 dB and  18 dB. The best performance SNR for mobility of user with speed    = 40 km/h value SNR 18 dB for BER . This research has proposed to show impact of power transmit and interference in performance NOMA.

scholarly journals Evaluation of 5G Key Technique: Non-Orthogonal Multiple Access

2019 ◽  
Vol 8 (2S8) ◽  
pp. 1314-1316
Keyword(s):  
Power Allocation ◽  
Spectral Efficiency ◽  
Interference Cancellation ◽  
Multiple Access ◽  
Quality Data ◽  
Data Service ◽  
Front Edge ◽  
Power Domain ◽  
Channel Interference ◽  
Code Domain

Non-orthogonal multiple access has been put forward as a key technique for 5G. It can provide power-domain and code-domain multiplexing and enables to satisfy the data demand. Its capacity and spectral efficiency are investigated-ed and analyzed. In comparison to the conventional orthogonal multiple access, the existing dominant non-orthogonal multiple access can provide a higher quality data service for multiple users when the transmitted signals are empowered by the power allocation technique and the received signals are decoded by the channel interference cancellation scheme. In this study, NOMA is found to be a front-edge technology the 5G communications.

Uplink Power-Domain Non-Orthogonal Multiple Access (NOMA)

2020 ◽  
Vol 12 (4) ◽  
pp. 65-73
Author(s):  
Faeik T. Al Rabee ◽  
Richard D. Gitlin
Keyword(s):  
Channel Estimation ◽  
Interference Cancellation ◽  
Multiple Access ◽  
Signal To Noise Ratio ◽  
Estimation Error ◽  
Channel Estimation Error ◽  
Estimation Errors ◽  
Channel Estimation Errors ◽  
Fifth Generation ◽  
Power Domain

Non-orthogonal multiple access (NOMA) has been proposed as a promising multiple access (MA) technique in order to meet the requirements for fifth generation (5G) communications and to enhance the performance in internet of things (IoT) networks by enabling massive connectivity, high throughput, and low latency. This paper investigates the bit error rate (BER) performance of two-user uplink power-domain NOMA with a successive interference cancellation (SIC) receiver and taking into account channel estimation errors. The analysis considers two scenarios: perfect (ideal) channel estimation and a channel with estimation errors for various modulations schemes, BPSK, QPSK, and 16-QAM. The simulation results show that, as expected, increasing of the modulation level increases the SIC receiver BER. For example, at a signal-to-noise ratio (SNR) of 5 dB for perfect channel estimation and QPSK modulation, the user that is detected first has a BER of 0.005 compared to 0.14 for the user that is detected with the aid of the SIC receiver. Similarly, the BER of QPSK, assuming 0.25 channel estimation error of user 1, is equal to 0.06 at SNR = 15 dB compared to 0.017 for perfect estimation.

scholarly journals Nothing but hot air?—On the molecular ballistic analysis of backspatter generated by and the hazard potential of blank guns

2021 ◽  
Author(s):  
Jan Euteneuer ◽  
Annica Gosch ◽  
Cornelius Courts
Keyword(s):  
Correct Identification ◽  
Str Typing ◽  
Comprehensive Overview ◽  
Biological Investigation ◽  
Biological Targets ◽  
Hazard Potential ◽  
Hot Air ◽  
Different Types ◽  
Blank Cartridge ◽  
Blank Cartridges

AbstractBlank cartridge guns are prevalent especially in countries with laws restricting access to conventional firearms, and it is a common misconception that these weapons are harmless and only used as toys or for intimidation. However, although their harming potential is well-documented by numerous reports of accidents, suicides, and homicides, a systematic molecular biological investigation of traces generated by shots from blank cartridges at biological targets has not been done so far. Herein, we investigate the occurrence and analyzability of backspatter generated by shots of different types of blank cartridge guns firing different types of blank ammunition at ballistic gelatin model cubes doped with human blood and radiological contrast agent soaked into a spongious matrix and covered with three different variants of skin simulants. All skin simulants were penetrated, and backspatter was created in 100% of the shots in amounts sufficient for forensic short tandem repeat (STR) typing that resulted in the correct identification of the respective blood donor. Visible backspatter was documented on the muzzle and/or inside the barrel in all cases, and in 75% of cases also on the outer surfaces and on the shooter’s hand(s). Wound cavities were measured and ranged between 1 and 4.5 cm in depth. Discussing our findings, we provide recommendations for finding, recovering, and analyzing trace material from blank guns, and we demonstrate the considerable hazard potential of these devices, which is further emphasized by the presentation of a comprehensive overview of the pertinent literature on injuries inflicted by blank guns.

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