scholarly journals Delivering more to cell edge via joint multi‐cell non‐orthogonal multiple access and traffic offloading

IET Networks ◽  
2021 ◽  
Author(s):  
Yi Zhao ◽  
Di Yuan ◽  
Lei You
Keyword(s):  
Multiple Access ◽  
Cell Edge ◽  
Traffic Offloading

Performance Analysis Of Non-Orthogonal Multiple Access Technique Using Simulink

2021 ◽  
Vol 9 (7) ◽  
pp. 921-928
Keyword(s):  
Multiple Access ◽  
Additive White Gaussian Noise ◽  
Multipath Fading ◽  
Rician Fading ◽  
Similar Data ◽  
Cell Edge ◽  
Novel Technology ◽  
Cell Coverage ◽  
Power Domain ◽  
Rician Fading Channel

Non orthogonal multiple access (NOMA) is a novel technology for transmission of the data with similar data-rate for users both at the cell center and the at cell edge. Due to its good cell coverage and large transmission bandwidth enables reliable communication for users located at the cell edge. The signals for the users are transmitted through entire spatial bandwidth by multiplexing in the power domain. This work presents the Simulink implementation of non-orthogonal multiple access over additive white Gaussian noise channel, Rayleigh and Rician fading channel. The NOMA Transmitter and the receiver blocks with SIC are implemented for two user and three user environments. Multipath fading environment was providing using parameter settings available in theblocks. Performance of the models implemented are analyzed with respect to Bit error rate (BER) v/s Eb/Noplots comparing using various modulation schemes over various channels. The results are tabulated and analyzed.

Cooperative multiple access in cognitive radios to enhance QoS for cell edge primary users: asynchronous algorithm and convergence

2015 ◽  
Vol 61 (4) ◽  
pp. 631-643
Author(s):  
Sang-wook Han ◽  
Hoon Kim ◽  
Youngnam Han ◽  
John M. Cioffi ◽  
Victor C. M. Leung ◽  
...  
Keyword(s):  
Multiple Access ◽  
Cognitive Radios ◽  
Asynchronous Algorithm ◽  
Cell Edge ◽  
Primary Users

scholarly journals Rate-Splitting Multiple Access for Intelligent Reflecting Surface aided Multi-User Communications

2021 ◽  
Author(s):  
Ankur Bansal ◽  
Keshav Singh ◽  
Bruno Clerckx ◽  
Chih-Peng Li ◽  
Mohamed-Slim Alouini
Keyword(s):  
Interference Cancellation ◽  
Multiple Access ◽  
Base Station ◽  
Control Technique ◽  
Decode And Forward ◽  
Cell Edge ◽  
Single Antenna ◽  
Rate Splitting ◽  
Reflecting Surface ◽  
The Impact

Intelligent reflecting surface (IRS) has recently emerged as a promising technology for 6G wireless systems, due to its capability to reconfigure the wireless propagation environment. In this paper, we investigate a Rate-Splitting Multiple Access (RSMA) for IRS-assisted downlink system, where the base station (BS) communicates with single-antenna users with the help of an IRS. RSMA relies on rate-splitting (RS) at the BS and successive interference cancellation (SIC) at the users and provides a generalized multiple access framework. We derive a new architecture called IRS-RS that leverages the interplay between RS and IRS. For performance analysis, we utilize an \textit{on-off control technique} to control the passive beamforming vector of the IRS-RS and derive the closed-form expressions for outage probability of cell-edge users and near users. Moreover, we also analyze the outage behavior of cell-edge users for a sufficiently large number of reflecting elements. Additionally, we also analyze the outage performance of cooperative RS based decode-and-forward (DF)-assisted framework called DF-RS. Through simulation results, it is shown that the proposed framework outperforms the corresponding DF-RS, RS without IRS and IRS-assisted conventional non-orthogonal multiple access (NOMA) schemes. Furthermore, the impact of various system's parameters such as the number of IRS reflecting elements and the number of users on the system performance is revealed.

scholarly journals Stochastic Optimal Control for Buffer-Aided Cooperative Relaying Systems Using Nonorthogonal Multiple Access

2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Zhishan Deng ◽  
Qianyun Gong ◽  
Quanzhong Li ◽  
Jiayin Qin
Keyword(s):  
Optimization Algorithm ◽  
Multiple Access ◽  
Asymptotic Optimality ◽  
Low Complexity ◽  
Base Station ◽  
Cooperative Relaying ◽  
Cell Edge ◽  
Data Buffer ◽  
Lyapunov Optimization ◽  
Cell Edge User

In this paper, a multiple-cluster downlink multiple-input single-output (MISO) nonorthogonal multiple access (NOMA) system is considered. In each cluster, there are one central user and one cell-edge user. The central user has a data buffer with finite storage units, which will decode the cell-edge user’s message and store it at the data buffer. To enhance the performance of the cell-edge user, the central user operates as a relay and helps forward the message to the cell-edge user. Our objective is to maximize the long-term average sum rates for the cell-edge users by designing the beamforming vectors and online power control, under the constraints of the data buffer causality, required information rates for central users, and transmit power at the base station and central users. Based on the current buffer state and the channel state information, we propose a low-complexity online Lyapunov optimization algorithm combined with a constrained concave-convex procedure (CCCP) to solve the causal and nonconvex problem. Furthermore, we verify the asymptotic optimality of the proposed online Lyapunov optimization algorithm. Simulation results demonstrate that our proposed scheme performs better than the greedy algorithm and the orthogonal multiple access (OMA) scheme.

scholarly journals On the Performance Evaluations of Cooperative Retransmission Scheme for Cell-Edge Users of URLLC in Multi-Carrier Downlink NOMA Systems

Sensors ◽  
2021 ◽  
Vol 21 (21) ◽  
pp. 7052
Author(s):  
Won-Jae Ryu ◽  
Jae-Woo Kim ◽  
Soo-Young Shin ◽  
Dong-Seong Kim
Keyword(s):  
Multiple Access ◽  
Prior Information ◽  
Loss Rate ◽  
High Reliability ◽  
Packet Loss Rate ◽  
Performance Evaluations ◽  
Cell Edge ◽  
Low Snr ◽  
Reliability Constraint ◽  
Cell Edge User

Non-orthogonal multiple access (NOMA) has a key feature that the cell-center user (CCU) has prior information about the messages of the cell-edge user(CEU) in the same user-pair. It means that CCU can be used for retransmission when the CEU requests retransmission. As ultra-reliability and low-latency communication (URLLC) requires high-reliability constraints (e.g., 99.999%), using CCU for retransmission can be useful to satisfy the reliability constraint. In this study, to ensure the reliability of CEU, cooperative retransmission (CR) scheme for downlink NOMA systems is proposed. And the CR scheme is evaluated with Block error rate (BLER) considering reliability and with packet loss rate (PLR) in terms of reliability and latency constraints. And the evaluation results showed that the proposed CR scheme can satisfy the target BLER for URLLC low SNR compared to the conventional retransmission scheme, and showed the improved PLR compared to the conventional retransmission scheme in low SNRs.

scholarly journals Rate-Splitting Multiple Access for Intelligent Reflecting Surface aided Multi-User Communications

2021 ◽  
Author(s):  
Ankur Bansal ◽  
Keshav Singh ◽  
Bruno Clerckx ◽  
Chih-Peng Li ◽  
Mohamed-Slim Alouini
Keyword(s):  
Interference Cancellation ◽  
Multiple Access ◽  
Base Station ◽  
Control Technique ◽  
Decode And Forward ◽  
Cell Edge ◽  
Single Antenna ◽  
Rate Splitting ◽  
Reflecting Surface ◽  
The Impact

Intelligent reflecting surface (IRS) has recently emerged as a promising technology for 6G wireless systems, due to its capability to reconfigure the wireless propagation environment. In this paper, we investigate a Rate-Splitting Multiple Access (RSMA) for IRS-assisted downlink system, where the base station (BS) communicates with single-antenna users with the help of an IRS. RSMA relies on rate-splitting (RS) at the BS and successive interference cancellation (SIC) at the users and provides a generalized multiple access framework. We derive a new architecture called IRS-RS that leverages the interplay between RS and IRS. For performance analysis, we utilize an \textit{on-off control technique} to control the passive beamforming vector of the IRS-RS and derive the closed-form expressions for outage probability of cell-edge users and near users. Moreover, we also analyze the outage behavior of cell-edge users for a sufficiently large number of reflecting elements. Additionally, we also analyze the outage performance of cooperative RS based decode-and-forward (DF)-assisted framework called DF-RS. Through simulation results, it is shown that the proposed framework outperforms the corresponding DF-RS, RS without IRS and IRS-assisted conventional non-orthogonal multiple access (NOMA) schemes. Furthermore, the impact of various system's parameters such as the number of IRS reflecting elements and the number of users on the system performance is revealed.

scholarly journals Rate-Splitting Multiple Access for Intelligent Reflecting Surface aided Multi-User Communications

2021 ◽  
Author(s):  
Ankur Bansal ◽  
Keshav Singh ◽  
Bruno Clerckx ◽  
Chih-Peng Li ◽  
Mohamed-Slim Alouini
Keyword(s):  
Interference Cancellation ◽  
Multiple Access ◽  
Base Station ◽  
Control Technique ◽  
Decode And Forward ◽  
Cell Edge ◽  
Single Antenna ◽  
Rate Splitting ◽  
Reflecting Surface ◽  
The Impact

Intelligent reflecting surface (IRS) has recently emerged as a promising technology for 6G wireless systems, due to its capability to reconfigure the wireless propagation environment. In this paper, we investigate a Rate-Splitting Multiple Access (RSMA) for IRS-assisted downlink system, where the base station (BS) communicates with single-antenna users with the help of an IRS. RSMA relies on rate-splitting (RS) at the BS and successive interference cancellation (SIC) at the users and provides a generalized multiple access framework. We derive a new architecture called IRS-RS that leverages the interplay between RS and IRS. For performance analysis, we utilize an \textit{on-off control technique} to control the passive beamforming vector of the IRS-RS and derive the closed-form expressions for outage probability of cell-edge users and near users. Moreover, we also analyze the outage behavior of cell-edge users for a sufficiently large number of reflecting elements. Additionally, we also analyze the outage performance of cooperative RS based decode-and-forward (DF)-assisted framework called DF-RS. Through simulation results, it is shown that the proposed framework outperforms the corresponding DF-RS, RS without IRS and IRS-assisted conventional non-orthogonal multiple access (NOMA) schemes. Furthermore, the impact of various system's parameters such as the number of IRS reflecting elements and the number of users on the system performance is revealed.

Sign in / Sign up

Export Citation Format

Share Document