scholarly journals Ergodic sum rate of transmitting antenna selection in non-orthogonal multiple access for modern systems

2018 ◽  
Vol 7 (3.29) ◽  
pp. 61
Author(s):  
M Ravi Sankar ◽  
Dr K. V. Satyanarayana
Keyword(s):  
High Throughput ◽  
Multiple Access ◽  
Antenna Selection ◽  
Multiple Antennas ◽  
High Capacity ◽  
Wireless Systems ◽  
Base Station ◽  
Single Base ◽  
Sum Rate ◽  
Transmitting Antenna

Wireless systems hiring multiple antennas at the transmitter side used for the transmission of the high capacity information through the channels making the system more complex and costlier. To overcome these problems, the multiple antennas at the transmitter side must be reduced and the performance should retained with reduced antennas as earlier. This can be achieved by using the algorithm Transmitting Antenna Selection (TAS) which is carried out by considering the transmission of the information through the channels using the Non-Orthogonal Multiple Access (NOMA). The NOMA algorithm is used to provide the high throughput using the heterogeneous demands in which there is no interference between the transmitted signals from the multiple antennas equipped in a single base station. TAS-NOMA algorithm is proposed in this paper for selecting the best transmitting antenna out of multiple antennas equipped in the base station by using the Ergodic sum rate which is measured at the transmitter side considering the average of the channels capacity.  

scholarly journals Low Power Allocation Based Error Improvements in wireless 5G

2019 ◽  
Vol 8 (4) ◽  
pp. 11049-11052
Keyword(s):  
Multiple Access ◽  
Antenna Selection ◽  
Base Station ◽  
Time Varying ◽  
Transmit Antenna Selection ◽  
User Experiences ◽  
Common Technique ◽  
Sum Rate ◽  
Simulation Results ◽  
Time Varying Channel

Transmit antenna selection is very common technique to reduce system complexity and power consumption at transmitter side while maintaining nearly the same performance of multiple antennas. In this paper, we introduce a transmit antenna selection (TAS) scheme for non orthogonal multiple access (NOMA) to improve the performance in terms of total sum rate. Therefore different antenna elements added at the base station experiences different fading conditions (A channel is a time varying channel).Experiences different SNR values adding more number of antennas at the base station. Increases the complaxicity as well as the performance with respect to the sum rate Non linear the user experiences the Bit error rate at the receiver simulation results shows that the BER is verified for different antenna error consideration (MIMO).

scholarly journals Novel Resource Allocation Techniques for Downlink Non-Orthogonal Multiple Access Systems

2020 ◽  
Vol 10 (17) ◽  
pp. 5892 ◽  
Author(s):  
Zuhura J. Ali ◽  
Nor K. Noordin ◽  
Aduwati Sali ◽  
Fazirulhisyam Hashim ◽  
Mohammed Balfaqih
Keyword(s):  
Resource Allocation ◽  
Energy Efficiency ◽  
Power Allocation ◽  
Multiple Access ◽  
High Capacity ◽  
Kkt Conditions ◽  
Optimal Power Allocation ◽  
User Pairing ◽  
Optimal Power ◽  
Sum Rate

Non-orthogonal multiple access (NOMA) plays an important role in achieving high capacity for fifth-generation (5G) networks. Efficient resource allocation is vital for NOMA system performance to maximize the sum rate and energy efficiency. In this context, this paper proposes optimal solutions for user pairing and power allocation to maximize the system sum rate and energy efficiency performance. We identify the power allocation problem as a nonconvex constrained problem for energy efficiency maximization. The closed-form solutions are derived using Karush–Kuhn–Tucker (KKT) conditions for maximizing the system sum rate and the Dinkelbach (DKL) algorithm for maximizing system energy efficiency. Moreover, the Hungarian (HNG) algorithm is utilized for pairing two users with different channel condition circumstances. The results show that with 20 users, the sum rate of the proposed NOMA with optimal power allocation using KKT conditions and HNG (NOMA-PKKT-HNG) is 6.7% higher than that of NOMA with difference of convex programming (NOMA-DC). The energy efficiency with optimal power allocation using DKL and HNG (NOMA-PDKL-HNG) is 66% higher than when using NOMA-DC.

scholarly journals Ambient BackCom in Beyond 5G NOMA Networks: A Multi-Cell Resource Allocation Framework

2021 ◽  
Author(s):  
Wali Ullah Khan ◽  
Kapal Dev ◽  
Muhammad Awais Javed ◽  
Dinh-Thuan Do ◽  
Nawab Muhammad Faseeh Qureshi ◽  
...  
Keyword(s):  
Resource Allocation ◽  
Multiple Access ◽  
Optimization Problem ◽  
Original Problem ◽  
Base Station ◽  
Joint Optimization ◽  
Theory Approach ◽  
Closed Form Solutions ◽  
Cell Network ◽  
Sum Rate

This article proposes a new resource allocation framework that uses the dual theory approach. Specifically, the sum-rate of the multi-cell network having backscatter tags and NOMA user equipments is maximized by formulating a joint optimization problem. To find the efficient base station transmit power and backscatter reflection coefficient in each cell, the original problem is first divided into two subproblems and then derived the closed-form solutions. A comparison with the orthogonal multiple access (OMA) ambient BackCom and pure NOMA transmission has been provided.

scholarly journals A Novel Fairness-Aware Resource Allocation Scheme in Multiuser SISO-OFDMA Downlink

2010 ◽  
Vol 2010 ◽  
pp. 1-10 ◽  
Author(s):  
Vasileios D. Papoutsis ◽  
Ioannis G. Fraimis ◽  
Stavros A. Kotsopoulos
Keyword(s):  
Resource Allocation ◽  
Multiple Access ◽  
Computational Cost ◽  
Wireless Systems ◽  
Base Station ◽  
Proportional Fairness ◽  
Allocation Scheme ◽  
Single Input Single Output ◽  
Data Rates ◽  
Resource Allocation Scheme

The problem of resource allocation for the downlink of wireless systems operating over a frequency-selective channel is investigated. It is assumed that both the Base Station (BS) and each user are equipped with a single antenna (Single Input Single Output-SISO case), and Orthogonal Frequency Division Multiple Access (OFDMA) is used as a multiple access scheme. The aim is to maximize the sum of the users' data rates subject to constraints on total available power and proportional fairness among users' data rates. Achieving the optimal solution has a high computational cost thereby the use of suboptimal techniques is necessary. A suboptimal, but efficient, scheme is devised, and it is shown, via simulation, that not only the proposed resource allocation scheme achieve higher sum of the users' data rates than other existing schemes but also the sum data rate is distributed fairly and flexibly among users. In addition, the proposed scheme is complexity effective and can be applied to latest-generation wireless systems that provide Quality-of-Service (QoS) guarantees.

scholarly journals Hybrid Direction of Arrival Precoding for Multiple Unmanned Aerial Vehicles Aided Non-Orthogonal Multiple Access in 6G Networks

2022 ◽  
Vol 12 (2) ◽  
pp. 895
Author(s):  
Laura Pierucci
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Multiple Access ◽  
Estimation Method ◽  
Direction Of Arrival ◽  
Base Station ◽  
Flying Height ◽  
Maximization Problem ◽  
Aerial Vehicles ◽  
Sum Rate ◽  
Hybrid Beamforming

Unmanned aerial vehicles (UAV) have attracted increasing attention in acting as a relay for effectively improving the coverage and data rate of wireless systems, and according to this vision, they will be integrated in the future sixth generation (6G) cellular network. Non-orthogonal multiple access (NOMA) and mmWave band are planned to support ubiquitous connectivity towards a massive number of users in the 6G and Internet of Things (IOT) contexts. Unfortunately, the wireless terrestrial link between the end-users and the base station (BS) can suffer severe blockage conditions. Instead, UAV relaying can establish a line-of-sight (LoS) connection with high probability due to its flying height. The present paper focuses on a multi-UAV network which supports an uplink (UL) NOMA cellular system. In particular, by operating in the mmWave band, hybrid beamforming architecture is adopted. The MUltiple SIgnal Classification (MUSIC) spectral estimation method is considered at the hybrid beamforming to detect the different direction of arrival (DoA) of each UAV. We newly design the sum-rate maximization problem of the UAV-aided NOMA 6G network specifically for the uplink mmWave transmission. Numerical results point out the better behavior obtained by the use of UAV relays and the MUSIC DoA estimation in the Hybrid mmWave beamforming in terms of achievable sum-rate in comparison to UL NOMA connections without the help of a UAV network.

Capacity Limits of Base Station Cooperation in Cellular Networks

2010 ◽  
pp. 102-132
Author(s):  
Symeon Chatzinotas ◽  
Muhammad Ali Imran ◽  
Reza Hoshyar
Keyword(s):  
Channel Model ◽  
High Capacity ◽  
Path Loss ◽  
Base Station ◽  
Cellular Systems ◽  
Current Channel ◽  
Capacity Limits ◽  
Base Station Cooperation ◽  
Rate Capacity ◽  
Sum Rate

In the information-theoretic literature, it has been widely shown that multicell processing is able to provide high capacity gains in the context of cellular systems. What is more, it has been proved that the per-cell sum-rate capacity of multicell processing systems grows linearly with the number of base station (BS) receive antennas. However, the majority of results in this area have been produced assuming that the fading coefficients of the MIMO subchannels are completely uncorrelated. In this direction, this chapter investigates the ergodic per-cell sum-rate capacity of the Gaussian MIMO cellular channel under correlated fading and BS cooperation (multicell processing). More specifically, the current channel model considers Rayleigh fading, uniformly distributed user terminals (UTs) over a planar cellular system, and power-law path loss. Furthermore, both BSs and UTs are equipped with correlated multiple antennas, which are modelled according to the Kronecker product correlation model. The per-cell sum-rate capacity is evaluated while varying the cell density of the system, as well as the level of receive and transmit correlation. In this context, it is shown that the capacity performance is compromised by correlation at the BS-side, whereas correlation at the UT-side has a negligible effect on the system’s capacity.

scholarly journals Ambient BackCom in Beyond 5G NOMA Networks: A Multi-Cell Resource Allocation Framework

2021 ◽  
Author(s):  
Wali Ullah Khan ◽  
Kapal Dev ◽  
Muhammad Awais Javed ◽  
Dinh-Thuan Do ◽  
Nawab Muhammad Faseeh Qureshi ◽  
...  
Keyword(s):  
Resource Allocation ◽  
Multiple Access ◽  
Optimization Problem ◽  
Original Problem ◽  
Base Station ◽  
Joint Optimization ◽  
Theory Approach ◽  
Closed Form Solutions ◽  
Cell Network ◽  
Sum Rate

This article proposes a new resource allocation framework that uses the dual theory approach. Specifically, the sum-rate of the multi-cell network having backscatter tags and NOMA user equipments is maximized by formulating a joint optimization problem. To find the efficient base station transmit power and backscatter reflection coefficient in each cell, the original problem is first divided into two subproblems and then derived the closed-form solutions. A comparison with the orthogonal multiple access (OMA) ambient BackCom and pure NOMA transmission has been provided.

scholarly journals Power Allocation for Energy-Harvesting-based Fading Cognitive Multiple Access Channels: with or without Successive Interference Cancellation

2017 ◽  
Vol 63 (1) ◽  
pp. 65-72
Author(s):  
Qun Li ◽  
Ding Xu
Keyword(s):  
Power Allocation ◽  
Interference Cancellation ◽  
Multiple Access ◽  
Base Station ◽  
Successive Interference Cancellation ◽  
Multiple Access Channel ◽  
Power Constraint ◽  
Transmit Power ◽  
Sum Rate ◽  
Power Limit

Abstract This paper considers a fading cognitive multiple access channel (CMAC), where multiple secondary users (SUs), who share the spectrum with a primary user (PU), transmit to a cognitive base station (CBS). A power station is assumed to harvest energy from the nature and then provide power to the SUs. We investigate the power allocation problems for such a CMAC to maximize the SU sum rate under the interference power constraint, the sum transmit power constraint and the peak transmit power constraint of each individual SU. In particular, two scenarios are considered: with successive interference cancellation (SIC) and without SIC. For the first scenario, the optimal power allocation algorithm is derived. For the second scenario, a heuristic algorithm is proposed. We show that the proposed algorithm with SIC outperforms the algorithm without SIC in terms of the SU sum rate, while the algorithm without SIC outperforms the algorithm with SIC in terms of the number of admitted SUs for a high sum transmit power limit and a low peak transmit power limit of each individual SU.

scholarly journals Transmit Antenna Selection Schemes for NOMA with Randomly Moving Interferers in Interference-Limited Environment

Electronics ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 36
Author(s):  
Dinh-Thuan Do ◽  
Thanh-Luan Nguyen ◽  
Byung Moo Lee
Keyword(s):  
Stochastic Geometry ◽  
Multiple Access ◽  
Poisson Point Process ◽  
Antenna Selection ◽  
Ergodic Capacity ◽  
Base Station ◽  
Selection Strategy ◽  
Practical Consideration ◽  
Transmit Antenna Selection ◽  
Spatial Topology

In this paper, non-orthogonal multiple access (NOMA) is studied at downlink under impact of surrounding interference. This study benefits the practical NOMA system since spatially random interference is adopted. More specifically, we consider the antenna selection strategy applied at the base station and compare the performance of two users. By applying a stochastic geometry-based model, homogeneous Poisson point process (PPP) is employed to consider the spatial topology of interference which is located near to users, and such a model is extremely suitable for practical consideration. We first consider outage probability and then ergodic capacity is examined as main metrics to recommend such model in practice. According to the considered antenna section scheme of the base station, we compare these schemes related to selected antenna serving each user. To confirm exactness of derived expressions, we perform Monte Carlo simulations to verify the analytical results.

scholarly journals Exploiting Joint Base Station Equipped Multiple Antenna and Full-Duplex D2D Users in Power Domain Division Based Multiple Access Networks

Sensors ◽  
2019 ◽  
Vol 19 (11) ◽  
pp. 2475 ◽  
Author(s):  
Dinh-Thuan Do ◽  
Minh-Sang Van Nguyen ◽  
Thi-Anh Hoang ◽  
Byung Moo Lee
Keyword(s):  
Multiple Access ◽  
Antenna Selection ◽  
Base Station ◽  
Base Stations ◽  
Full Duplex ◽  
Mobile Users ◽  
Multiple Antenna ◽  
Transmit Antenna Selection ◽  
Single Output ◽  
Power Domain

In this paper, we investigate power domain division-based multiple access (PDMA) to support the base stations (BS) equipped with multiple antennas to serve mobile users. Such a system deploys multiple input single output (MISO)-based wireless transmission and a full-duplex (FD) scheme. Furthermore, such MISO PDMA system consists of BS employing transmit antenna selection to reduce complexity in signal processing at the receivers. We distinguish two kinds of mobile users, device-to-device (D2D) users and traditional users. In such MISO PDMA, there exists a trade-off between outage performance of each PDMA user and power allocation factors. Since the implementation of the FD scheme at PDMA users, bandwidth efficiency will be enhanced despite the existence of self-interference related to such FD. In particular, exact expressions of outage probability are derived to exhibit system performance with respect to D2D users. Finally, valuable results from the simulated parameters together with the analytical results show that MISO PDMA can improve its performance by increasing the number of transmit antennas at the BS.

Sign in / Sign up

Export Citation Format

Share Document