scholarly journals I/Q Imbalance and Imperfect SIC on Two-Way Relay NOMA Systems

Electronics ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 249 ◽  
Author(s):  
Xinji Tian ◽  
Qianqian Li ◽  
Xingwang Li ◽  
Hongxing Peng ◽  
Changsen Zhang ◽  
...  
Keyword(s):  
Outage Probability ◽  
Fading Channels ◽  
Interference Cancellation ◽  
Signal To Noise Ratio ◽  
High Reliability ◽  
System Throughput ◽  
Rician Fading ◽  
High Signal ◽  
Decode And Forward ◽  
Outage Performance

Non-orthogonal multiple access (NOMA) system can meet the demands of ultra-high data rate, ultra-low latency, ultra-high reliability and massive connectivity of user devices (UE). However, the performance of the NOMA system may be deteriorated by the hardware impairments. In this paper, the joint effects of in-phase and quadrature-phase imbalance (IQI) and imperfect successive interference cancellation (ipSIC) on the performance of two-way relay cooperative NOMA (TWR C-NOMA) networks over the Rician fading channels are studied, where two users exchange information via a decode-and-forward (DF) relay. In order to evaluate the performance of the considered network, analytical expressions for the outage probability of the two users, as well as the overall system throughput are derived. To obtain more insights, the asymptotic outage performance in the high signal-to-noise ratio (SNR) region and the diversity order are analysed and discussed. Throughout the paper, Monte Carlo simulations are provided to verify the accuracy of our analysis. The results show that IQI and ipSIC have significant deleterious effects on the outage performance. It is also demonstrated that the outage behaviours of the conventional OMA approach are worse than those of NOMA. In addition, it is found that residual interference signals (IS) can result in error floors for the outage probability and zero diversity orders. Finally, the system throughput can be limited by IQI and ipSIC, and the system throughput converges to a fixed constant in the high SNR region.

scholarly journals Performance Analysis of Cooperative NOMA Networks with Imperfect CSI over Nakagami-m Fading Channels

Sensors ◽  
2020 ◽  
Vol 20 (2) ◽  
pp. 424 ◽  
Author(s):  
Xianli Gong ◽  
Xinwei Yue ◽  
Feng Liu
Keyword(s):  
Outage Probability ◽  
Fading Channels ◽  
Multiple Access ◽  
Base Station ◽  
High Signal ◽  
Direct Link ◽  
Decode And Forward ◽  
Estimation Errors ◽  
Channel Estimation Errors ◽  
Outage Performance

In this paper, we investigate a downlink cooperative non-orthogonal multiple access (NOMA) network with decode-and-forward relaying, where two scenarios of user relaying with direct link and user relaying without direct link are discussed in detail. More particularly, the performance of cooperative NOMA system under the assumption of imperfect channel state information (ipCSI) is studied over Nakagami-m fading channels. To evaluate the outage performance of the above discussed two scenarios, the closed-form expressions of outage probability for a pair of users are derived carefully. The diversity orders of users are achieved in the high signal-to-noise region. An error floor appears in the outage probability owing to the existence of channel estimation errors under ipCSI conditions. Simulation results verify the validity of our analysis and show that: (1) NOMA is superior to conventional orthogonal multiple access; (2) The best user relaying location for cooperative NOMA networks should be near to the base station; and (3) The outage performance of distant user with direct link significantly outperforms distant user without direct link by comparing the two scenarios.

scholarly journals Secrecy Performance Analysis of Half/Full Duplex AF/DF Relaying in NOMA Systems Over κ - μ Fading Channels

2021 ◽  
Author(s):  
Nesrine Zaghdoud ◽  
Adel Ben Mnaouer ◽  
Hatem Boujemaa ◽  
Farid Touati
Keyword(s):  
Fading Channels ◽  
Signal To Noise Ratio ◽  
Multipath Fading ◽  
Full Duplex ◽  
High Signal ◽  
Secrecy Outage Probability ◽  
Amplify And Forward ◽  
Decode And Forward ◽  
Special Cases ◽  
Secrecy Outage

Abstract Although the progress in understanding 5G and beyond techniques such as Non-Orthogonal Multiple Access (NOMA) and full-duplex techniques has been overwhelming, still analyzing the security aspects of such systems under different scenarios and settings is an important concern that needs further exploration. In particular, when considering fading in wiretap channels and scenarios, achieving secrecy has posed many challenges. In this context, we propose to study the physical layer security (PLS) of cooperative NOMA (C-NOMA) system using the general fading distribution κ - μ. This distribution facilitates mainly the effect of light-of-sight as well as multipath fading. It also includes multiple distributions as special cases like: Rayleigh, Rice, Nakagami-m which help to understand the comportment of C-NOMA systems under different fading parameters. The use of Half-Duplex and Full-Duplex communication is also investigated for both Amplify-and-forward (AF) and Decode-and-Forward (DF) relaying protocols. To characterize the secrecy performance of the proposed C-NOMA systems, closed form expressions of the Secrecy Outage Probability (SOP) and the Strictly Positive Secrcey Capacity (SPSC) metrics for the strong and weak users are given for high signal-to-noise ratio (SNR) due to the intractable nature of the exact expressions. Based on the analytical analysis, numerical and simulation results are given under different network parameters.

scholarly journals Performance Analysis of Cooperative NOMA Systems with Incremental Relaying

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Zhenling Wang ◽  
Zhangyou Peng ◽  
Yongsheng Pei ◽  
Haojia Wang
Keyword(s):  
Performance Analysis ◽  
Outage Probability ◽  
Multiple Access ◽  
Signal To Noise Ratio ◽  
Amplify And Forward ◽  
Signal To Noise ◽  
Decode And Forward ◽  
Outage Performance ◽  
Low Snr ◽  
Incremental Relaying

In this paper, we investigate the performance of the non-orthogonal multiple access (NOMA) system with incremental relaying, where the relay is employed with amplify-and-forward (AF) or decode-and-forward (DF) protocols. To characterize the outage behaviors of the incremental cooperative NOMA (ICN) system, new closed-form expressions of both exact and asymptotic outage probability for two users are derived. In addition, the performance of the conventional cooperative NOMA (CCN) system is analyzed as a benchmark for the the purpose of comparison. We confirm that the outage performance of the distant user is enhanced when ICN system is employed. Numerical results are presented to demonstrate that (1) the near user of the ICN system achieves better outage behavior than that of the CCN system in the low signal-to-noise ratio (SNR) region; (2) the outage performance of distant user for the DF-based ICN system is superior to that of the AF-based ICN system when the system works in cooperative NOMA transmission mode; and (3) in the low SNR, the throughput of the ICN system is higher than that of the CCN system.

scholarly journals Performance Analysis of Hybrid Protocol Based AF EH Relaying over Asymmetric Fading Channels

Information ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 50 ◽  
Author(s):  
Xutao Sheng ◽  
Guangyue Lu ◽  
Liqin Shi ◽  
Yinghui Ye
Keyword(s):  
Fading Channels ◽  
Rayleigh Fading ◽  
Signal To Noise Ratio ◽  
System Capacity ◽  
Rician Fading ◽  
High Signal ◽  
Amplify And Forward ◽  
Relay Nodes ◽  
Energy Constrained ◽  
Selection Of

Simultaneous wireless information and power transfer is a practicable solution to encourage energy-constrained relay nodes to cooperate with the source to transmit information to the destination. In this paper, we study the outage performance of hybrid protocol based amplify-and-forward (AF) relay networks over asymmetric fading channels, where the source-relay link and the relay-destination link are subjected to Rician fading and Rayleigh fading, respectively. In particular, we derive the lower bound of outage probability and the upper bound of outage capacity based on a high signal-to-noise ratio approximation, respectively. We further investigate the effects of various system parameters, such as the parameters of hybrid protocol, the target rate, and the Rician K-factor, on the investigated network. It is shown that a good selection of parameters of hybrid protocol is of significance to improve system capacity, and that a larger Rician factor is desirable in the investigated network.

scholarly journals Performance Analysis of IQI Impaired Cooperative NOMA for 5G-Enabled Internet of Things

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Hui Guo ◽  
Xuejiao Guo ◽  
Chao Deng ◽  
Shangqing Zhao
Keyword(s):  
Internet Of Things ◽  
Outage Probability ◽  
Interference Cancellation ◽  
Multiple Access ◽  
Signal To Noise Ratio ◽  
Specific Power ◽  
High Signal ◽  
Quadrature Phase ◽  
Outage Probabilities ◽  
Iot Devices

This paper investigates the joint effects of in-phase and quadrature-phase imbalance (IQI) and imperfect successive interference cancellation (ipSIC) on the cooperative Internet of Things (IoT) nonorthogonal multiple access (NOMA) networks where the Nakagami-m fading channel is taken into account. The closed-form expressions of outage probability for the far and near IoT devices are derived to evaluate the outage behaviors. For deeper insights of the performance of the considered system, the approximate outage probability and diversity order in high signal-to-noise ratio (SNR) regime are obtained. In addition, we also analyze the throughput and energy efficiency to characterize the performance of the considered system. The simulation results demonstrate that, compared with IQI, ipSIC has a greater impact on the outage performance for the near-IoT-device of the considered system. Furthermore, we also find that the outage probabilities of IoT devices can be minimized by selecting a specific power allocation scheme.

Exact Outage Probability Analysis for Selection Decode-and-Forward Cooperation Systems

2011 ◽  
Vol 341-342 ◽  
pp. 509-513
Author(s):  
Yu Long Zou ◽  
Yu Dong Yao
Keyword(s):  
Outage Probability ◽  
Fading Channels ◽  
Signal To Noise Ratio ◽  
Source Node ◽  
Closed Form Expression ◽  
Decode And Forward ◽  
Full Diversity ◽  
Best Relay Selection ◽  
The One ◽  
Outage Analysis

In this paper, we present a selection decode-and- forward (S-DF) cooperation scheme where only the “best” relay, which is selected as the one who can decode correctly its received signal from source node and can achieve the highest instantaneous signal-to-noise ratio (SNR) at the destination, participates in relaying the source’s signal. We derive a novel exact closed-form expression of outage probability for the S-DF scheme over Rayleigh fading channels, based on which an asymptotic outage analysis is further presented in high SNR regime, showing that given M potential relays, M+1 diversity order is achieved by source node. Consequently, the proposed S-DF scheme with the best relay selection can achieve the full diversity at the expense of just two channels only regardless of the number of candidate relays.

scholarly journals Performance Analysis of Multi-Antenna Relay Networks over Nakagami-m Fading Channel

2013 ◽  
pp. 242-255
Author(s):  
E. Soleimani-Nasab ◽  
A. Kalantari ◽  
M. Ardebilipour
Keyword(s):  
Outage Probability ◽  
Fading Channels ◽  
Fading Channel ◽  
Error Probability ◽  
Signal To Noise Ratio ◽  
Relay Networks ◽  
Function Symbol ◽  
Statistical Characteristics ◽  
Decode And Forward ◽  
Analytical Formulas

In this chapter, the authors present the performance of multi-antenna selective combining decode-and-forward (SC-DF) relay networks over independent and identically distributed (i.i.d) Nakagami-m fading channels. The outage probability, moment generation function, symbol error probability and average channel capacity are derived in closed-form using the Signal-to-Noise-Ratio (SNR) statistical characteristics. After that, the authors formulate the outage probability problem, optimize it with an approximated problem, and then solve it analytically. Finally, for comparison with analytical formulas, the authors perform some Monte-Carlo simulations.

scholarly journals Physical Layer Secrecy Analysis of Multihop Hybrid Satellite-Terrestrial Relay Networks with Jamming

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Xiaoqi Wang ◽  
Hanwei Zhang ◽  
Zheng Hou
Keyword(s):  
Signal To Noise Ratio ◽  
Relay Network ◽  
Rician Fading ◽  
High Signal ◽  
Secrecy Outage Probability ◽  
Channel Fading ◽  
Network Resources ◽  
Decode And Forward ◽  
Secrecy Outage ◽  
Theoretical Results

This paper explores the secrecy analysis of a multihop hybrid satellite-terrestrial relay network (HSTRN) with jamming, where one satellite source is aimed at communicating with destination users via multihop decode-and-forward (DF) terrestrial relays, in the existence of an eavesdropper. All the destination users are deployed randomly following a homogeneous Poisson point process (PPP) based on stochastic geometry. Each relay operates not only as a conventional DF relay to forward the received signal but also as a jammer to generate intentional interference to degrade the eavesdropper link, considering shadowed-Rician fading for legitimate link and wiretap link while Rayleigh fading for jamming link. To characterize the secrecy performance of the considered network, the accurate analytical expression for the secrecy outage probability (SOP) is derived. In order to reveal further insights on the achievable diversity order of the network, the asymptotic behavior of SOP expression at high signal-to-noise ratio (SNR) region is deduced. Moreover, the throughput of the system is discussed to characterize the secrecy performance. Finally, the theoretical results are validated through comparison with simulation results and show that (1) the secrecy performance of the considered network gets better with the decreasing of the hops and with the decreasing severity of the channel fading scenario, (2) the relay of the network operating as a jammer can provide better secrecy performance without extra network resources, and (3) small hops and high SNR can yield to high throughput of the system.

scholarly journals MmWave V2X Cooperative Diversity Relay Channel with Feedback Delay and Link Blockage

2021 ◽  
Author(s):  
Elyes Balti
Keyword(s):  
Cooperative Diversity ◽  
Signal To Noise Ratio ◽  
Base Station ◽  
Maximal Ratio Combining ◽  
High Signal ◽  
Relay Channel ◽  
Framework Analysis ◽  
Decode And Forward ◽  
Multiple Transmit ◽  
To Receive

In this work, we present a framework analysis of a millimeter wave (mmWave) vehicular communications systems. Communications between vehicles take place through a cooperative relay which acts as an intermediary base station (BS). The relay is equipped with multiple transmit and receive antennas and it employs decode-and-forward (DF) to process the signal. Also, the relay applies maximal ratio combining (MRC), and maximal ratio transmission (MRT), respectively, to receive and forward the signal.As the vehicles' speeds are relative high, the channel experiences a fast fading and this time variation is modeled following the Jake's autocorrelation model. We also assume narrowband fading channel. Closed-form expressions of the reliability metrics such as the outage probability and the mean rate are derived. Capitalizing on these performances, we derive the high signal-to-noise-ratio (SNR) asymptotes to get full insights into the system gains such as the diversity and coding gains.

Sign in / Sign up

Export Citation Format

Share Document