Impact of CCI on Performance Analysis of Downlink Satellite-Terrestrial Systems: Outage Probability and Ergodic Capacity Perspective

Abstract The evolution of non-orthogonal multiple access (NOMA) has raised many opportunities for massive connectivity with less latency in signal transmissions at great distances. Power-Domain NOMA transmits user signals superimposed in the same resource block by varying the power coefficient of each user according to their channel state information (CSI). At the receiver’s end, successive interference cancellation (SIC) is performed to extract the desired signal from the superimposed signal. Imperfect CSI should therefore be studied in this context. Satellite-terrestrial networks and relay networks have already gained significance in the field of communications through their efficient data transmission techniques. We aimed to integrate NOMA with a satellite communications network under both imperfect CSI and co-channel interference (CCI) from nearby systems with respect to analysis of ground user performance. In our considered system, two users perform downlink communications under Power-Domain NOMA. We analyzed the performance of this system with two modes of shadowing effect: Heavy Shadowing (HS) and Average Shadowing (AS). Performance was analyzed in terms of the outage probability and ergodic capacity of the system. We derived closed-form expressions and performed a numerical analysis. We discovered that the performance of two destinations depends on the strength of the transmit power at the satellite. However, floor outage occurs because the system depends on other parameters, such as satellite link modes, noise levels, and the number of interference sources. More specifically, if, for example, the number of interference sources is 5, the outage performance of the system experiences a decrease of approximately 40% at a signal to noise ratio (SNR) of 30 dB at the satellite. Outage probability and ergodic capacity became saturated at SNRs of 50 dB and 45 dB, respectively. To verify the authenticity of the derived closed-form expressions, we also performed Monte-Carlo simulations.

Download Full-text

Enabling Non-Linear Energy Harvesting in Power Domain Based Multiple Access in Relaying Networks: Outage and Ergodic Capacity Performance Analysis

Electronics ◽

10.3390/electronics8070817 ◽

2019 ◽

Vol 8 (7) ◽

pp. 817 ◽

Cited By ~ 5

Author(s):

Thanh-Luan Nguyen ◽

Minh-Sang Van Nguyen ◽

Dinh-Thuan Do ◽

Miroslav Voznak

Keyword(s):

Energy Harvesting ◽

Outage Probability ◽

Multiple Access ◽

Signal To Noise Ratio ◽

Ergodic Capacity ◽

Green Communications ◽

Access Policy ◽

Power Domain ◽

Proposed Model ◽

Non Linear

The Power Domain-based Multiple Access (PDMA) scheme is considered as one kind of Non-Orthogonal Multiple Access (NOMA) in green communications and can support energy-limited devices by employing wireless power transfer. Such a technique is known as a lifetime-expanding solution for operations in future access policy, especially in the deployment of power-constrained relays for a three-node dual-hop system. In particular, PDMA and energy harvesting are considered as two communication concepts, which are jointly investigated in this paper. However, the dual-hop relaying network system is a popular model assuming an ideal linear energy harvesting circuit, as in recent works, while the practical system situation motivates us to concentrate on another protocol, namely non-linear energy harvesting. As important results, a closed-form formula of outage probability and ergodic capacity is studied under a practical non-linear energy harvesting model. To explore the optimal system performance in terms of outage probability and ergodic capacity, several main parameters including the energy harvesting coefficients, position allocation of each node, power allocation factors, and transmit signal-to-noise ratio (SNR) are jointly considered. To provide insights into the performance, the approximate expressions for the ergodic capacity are given. By matching analytical and Monte Carlo simulations, the correctness of this framework can be examined. With the observation of the simulation results, the figures also show that the performance of energy harvesting-aware PDMA systems under the proposed model can satisfy the requirements in real PDMA applications.

Download Full-text

Outage probability and ergodic capacity for MIMO-MRT systems under co-channel interference and imperfect CSI

2011 IEEE Swedish Communication Technologies Workshop (Swe-CTW) ◽

10.1109/swe-ctw.2011.6082487 ◽

2011 ◽

Cited By ~ 2

Author(s):

Thi My Chinh Chu ◽

Trung Q. Duong ◽

Hans-Jurgen Zepernick

Keyword(s):

Outage Probability ◽

Ergodic Capacity ◽

Imperfect Csi ◽

Channel Interference

Download Full-text

Performance of Multibeam Very High Throughput Satellite Systems Based on FSO Feeder Links with HPA Nonlinearity

10.36227/techrxiv.12413384 ◽

2020 ◽

Author(s):

Emna Zedini ◽

Abla Kammoun ◽

Mohamed-Slim Alouini

Keyword(s):

Outage Probability ◽

High Throughput ◽

Direct Detection ◽

Satellite Communications ◽

Ergodic Capacity ◽

Heterodyne Detection ◽

High Signal ◽

Free Space Optical ◽

Asymptotic Results ◽

Very High

Due to recent advances in laser satellite communications technology, free-space optical (FSO) links are presented as an ideal alternative to the conventional radio frequency (RF) feeder links of the geostationary satellite for next generation very high throughput satellite (VHTS) systems. In this paper, we investigate the performance of multibeam VHTS systems that account for nonlinear high power amplifiers at the transparent fixed gain satellite transponder. Specifically, we consider the forward link of such systems, where the RF user link is assumed to follow the shadowed Rician model and the FSO feeder link is modeled by the Gamma-Gamma distribution in the presence of beam wander and pointing errors where it operates under either the intensity modulation with direct detection or the heterodyne detection. Moreover, zero-forcing precoder is employed to mitigate the effect of inter-beam interference caused by the aggressive frequency reuse in the user link. The performance of the system under study is evaluated in terms of the outage probability, the average bit-error rate (BER), and the ergodic capacity that are derived in exact closed-forms in terms of the bivariate Meijer's G function. Simple asymptotic results for the outage probability and the average BER are also obtained at high signal-to-noise ratio.

Download Full-text

On the Performance Balancing for Uplink NOMA Systems

International Journal of Intelligent Engineering and Systems ◽

10.22266/ijies2020.1231.40 ◽

2020 ◽

Vol 13 (6) ◽

pp. 454-459

Author(s):

Nam-Soo Kim ◽

Keyword(s):

Outage Probability ◽

Multiple Access ◽

Signal To Noise Ratio ◽

Ergodic Capacity ◽

Base Station ◽

Cellular Systems ◽

Mobile Cellular ◽

Noise Ratio ◽

Outage Probabilities ◽

Error Floors

Outage probability and capacity are the representative performance measures for the quality of service (QoS) in mobile cellular systems. Recently, power back-off scheme is proposed in uplink non-orthogonal multiple access (NOMA) systems. The power back-off scheme improves the performance of a near user, however, decreases that of a far user. In comparison, the scheme indicates the error floors with an outage probability of 2.4×〖10〗^(-1) and 9.1×〖10〗^(-2) with power back-off 5 dB and 10 dB, respectively under the specified condition. To address these drawbacks, we propose an equal average signal-to–interference plus noise ratio (SINR) scheme that derives the same average SINR from active users at the base station (BS) in uplink non-orthogonal multiple access (NOMA) systems. Numerical results show that required signal-to-noise ratio (SNR) for the outage probability of 1×〖10〗^(-3) of the near and far users are close enough within 1 dB, which means an outage balance between two users. And it is noticed that the outage probabilities in the proposed scheme decrease as the increase of the received SNR without error floors. Also, different from the power back-off scheme, we noticed that the capacities of the two users in the proposed scheme are coincident and increase with SNR. The outage probabilities and ergodic capacity of the near and far users are derived in closed-form expressions. The analytical results are conformed by Monte Carlo simulation.

Download Full-text

Uplink IoT Networks: Time-Division Priority-Based Non-Orthogonal Multiple Access Approach

10.20944/preprints202103.0709.v1 ◽

2021 ◽

Author(s):

Basem M. Elhalawany ◽

Ahmad A.Aziz El-Banna ◽

Kaishun Wu ◽

Wali Ullah Khan

Keyword(s):

Power Allocation ◽

Spectral Efficiency ◽

Interference Cancellation ◽

Multiple Access ◽

Signal To Noise Ratio ◽

Ergodic Capacity ◽

Transmission Time ◽

Limited Power ◽

Iot Devices ◽

Time Division

Non-orthogonal multiple access (NOMA) has been investigated to support massive connectivity for Internet-of-things (IoT) networks. However, since most IoT devices suffer from limited power and decoding capabilities, it is not desirable to pair a large number of devices simultaneously, which encourages two-user NOMA grouping. Additionally, most existing techniques have not considered the diversity in the target QoS of IoT devices, which may lead to spectrum inefficiency. Few investigations have partially considered that issue by using an order-based power allocation (OPA) approach, where the power is allocated according to the order to the user's target throughput within a priority-based NOMA (PNOMA) group. However, this does not fully capture the effects of diversity in the values of the users' target throughputs. In this work, we handle both problems by considering a throughput-based power allocation (TPA) approach, that captures the QoS diversity, within a three-users PNOMA group as a compromise between spectral efficiency and complexity. Specifically, we investigate the performance of a time-division PNOMA (TD-PNOMA) scheme, where the transmission time is divided into two-time slots with two-users per PNOMA group. The performance of such TD-PNOMA is compared with a fully PNOMA (F-PNOMA) scheme, where the three users share the whole transmission time, in terms of the ergodic capacity under imperfect successive interference cancellation (SIC). The results reveal the superiority of TPA compared with OPA approach in both schemes, besides that the throughput of both schemes can outperform each other under imperfect SIC based on the transmit signal-to-noise ratio and the deployment scenarios.

Download Full-text

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

International Journal of Interdisciplinary Telecommunications and Networking ◽

10.4018/ijitn.2020100105 ◽

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.

Download Full-text

Novel approximate distribution of the sum of lognormal-Rician turbulence channels with pointing errors and applications in MIMO FSO links

10.36227/techrxiv.16566192.v1 ◽

2021 ◽

Author(s):

Xiaofeng Li ◽

maoke miao

Keyword(s):

Performance Analysis ◽

Outage Probability ◽

Closed Form ◽

Bit Error Rate ◽

Error Rate ◽

Ergodic Capacity ◽

New Method ◽

Pointing Errors ◽

Approximate Distribution ◽

Siso Systems

<p>The performance analysis for the MIMO-FSO systems employing EGC technology over Lognormal-Rician turbulence channels with pointing errors is important. However, the results so far are greatly limited since the PDF of Lognormal-Rician turbulence channels is not analytic, even for the SISO systems. In this paper, we propose a new method to approximate the sum of lognormal-Rician turbulence channels with Rayleigh pointing errors. Based on the developed formula, the approximate closed-form expressions of ergodic capacity, outage probability, and bit-error rate are derived. Numerical results demonstrate the accuracy of the proposed approach.</p>

Download Full-text

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

Wireless Communications and Mobile Computing ◽

10.1155/2020/3812826 ◽

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.

Download Full-text