Performance Analysis of Cooperative Communication Systems PDF Download

Author: Hafiz Yasar Lateef
Publisher:
ISBN:
Category :
Languages : en
Pages : 234

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Author: Mohammad Jafar Taghiyar Renani
Publisher:
ISBN:
Category : Wireless communication systems
Languages : en
Pages : 0

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Space-time coding has demonstrated that the deployment of multiple antennas at the transmitter allows for simultaneous increase in throughput and reliability. However, the use of antenna arrays is impractical for deployment in some practical scenarios. Therefore, cooperative diversity has been recently introduced for realizing transmit diversity. Most of the literature in cooperative diversity assume perfect channel state information (CSI). However, in practice, imperfect CSI should be considered. In this thesis, we first investigate the performance of cooperative communications with imperfect CSI, where the channel estimates are obtained by pilot symbols. We present an exact bit error probability expression in the presence of channel estimation errors. We also study the effect of imperfect CSI in two-way multi-relay cooperative networks when the max-min relay selection is used. We derive an exact expression for the outage probability based on which a novel optimum power allocation scheme is proposed.

Author:
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Category :
Languages : en
Pages : 0

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Author: Rahat Ali Khan Langah
Publisher: LAP Lambert Academic Publishing
ISBN: 9783659197451
Category :
Languages : de
Pages : 68

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With the rapid growth of multimedia services, future generations of cellular communications require higher data rates and a more reliable transmission link while keeping satisfactory quality of service. In this respect, multiple input multiple-output (MIMO) antenna systems have been considered as an efficient approach to address these demands by offering significant multiplexing and diversity gains over single antenna systems without increasing requirements on radio resources such as bandwidth and power. Although MIMO systems can unfold their huge benefit in cellular base stations, they may face limitations when it comes to their deployment in mobile handsets. This work is based on cooperative communications in wireless networks. We focus on Bit error rate (BER) performance analysis of cooperative communications with either an amplify-and-forward (AF) or decode-and-forward (DF) cooperation protocol using Matlab. We consider the single and multi relay scenario in our simulations.

Author: Yong Zhou
Publisher:
ISBN:
Category : Ad hoc networks (Computer networks)
Languages : en
Pages : 103

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Wireless ad hoc networks have been attracting more and more attentions in recent years from both academia and industry, because of their low deployment costs and broad applications. Due to the scarcity of the radio spectrum, supporting concurrent transmissions by exploiting the spatial frequency reuse gain is necessary to enhance spectrum utilization. On the other hand, cooperative communication is a practical technique for realizing the spatial diversity gain to mitigate the detrimental effect of wireless channel and enhance the transmission reliability. Enabling concurrent cooperative transmissions across a network can achieve both types of gains. Due to the broadcast nature of wireless communications, the concurrent cooperative transmissions using the same radio channel generate interference to each other, which is the main performance-limiting factor. Accurate characterization of interference is a fundamental step towards evaluating the performance of cooperative communication in a wireless ad hoc network. However, the distributed network operation, random node locations, interference redistribution due to relay transmissions, and dynamic traffic arrival pose significant challenges in interference characterization. Under the protocol interference model, this thesis evaluates the effectiveness of cooperative communication in a wireless ad hoc network from a perspective of overall network performance through investigating the network throughput, which captures the tradeoff between single-link cooperation gain and network-wide reduced spatial frequency reuse due to relay transmissions. In particular, based on stochastic geometry, the outage probabilities of direct and cooperative transmissions are derived to characterize single-link cooperation gain. On the other hand, according to a randomized scheduling scheme, the expected numbers of concurrent direct and cooperative transmissions that can be accommodated within the network coverage area are calculated to characterize network-wide reduced spatial frequency reuse. The analytical results show that a locally beneficial cooperation decision is not guaranteed to be network-wide beneficial. The number of potential relays determines the achievable performance of a cooperative link, and varies for different source-destination pairs due to random relay locations. This thesis proposes an opportunistic cooperation strategy based on the number of potential relays available for each source-destination pair. Under the physical interference model, the correlation of node locations induces the correlation of interference power. Via modeling node locations as a Poisson point process (PPP) and based on the Campbell's theorem, the temporal correlation coefficient of interference power at a destination node is analyzed. In addition, we derive the outage probability of opportunistic cooperation while taking into account the spatial and temporal interference correlation. The overall network performance can be enhanced by adjusting the proportion of concurrent cooperative transmissions. In addition to random node locations and interference redistribution, dynamic traffic arrival further complicates the interference characterization. This thesis investigates the performance of cooperative communication in a wireless ad hoc network with unsaturated traffic, which introduces a correlation between the interferer density and packet retransmission probability. Based on queueing theory and stochastic geometry, the interference power is characterized from two aspects, namely stationary interferer density and interference correlation in two consecutive time-slots, to evaluate the network performance. The analytical results show that the performance analysis under the assumption of independent interference power overestimates the network performance. The proposed theoretical performance analysis framework provides a step towards better understanding of the benefits and limitations of cooperative communication in wireless ad hoc networks with spatially random nodes, and in turn provides useful insights on protocol design and parameter setting for large-scale networks.

Author: Hongzheng Wang
Publisher: Open Dissertation Press
ISBN: 9781374808713
Category : Technology & Engineering
Languages : en
Pages : 116

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This dissertation, "Performance Analysis of Cooperative Systems With Spatial Random Relays and Interfering Nodes" by Hongzheng, Wang, 王宏征, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. DOI: 10.5353/th_b4420504 Subjects: Internetworking (Telecommunication) Wireless communication systems Signal processing

Author: Mohammed Khalid Yousif
Publisher:
ISBN: 9783659901652
Category :
Languages : en
Pages : 100

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Author: Essam Saleh Altubaishi
Publisher:
ISBN:
Category :
Languages : en
Pages : 123

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Cooperative communication has recently become a key technology for modern wireless networks such as 3GPP long-term evolution and WiMAX, because in such networks the transmission rate, the communication reliability, and coverage problems could be improved in a cost-effective manner. This, however, faces many design challenges. First, cooperative transmission typically involves a relaying phase which requires extra resources. This may cause a reduction in the spectral efficiency. Second, extra control signaling increases the complexity of operation, which may limit practical implementation. In addition, a wireless channel is time-varying, mainly due to the multipath propagation. As a result, a careful design of efficient cooperative communication systems is required, not only to enhance the spectral efficiency and maintain the quality-of-service (QoS), but also to be practical. In this dissertation, we aim to address the challenges imposed by cooperative communication and wireless transmission, and design the efficient and distributed systems which can be practically implemented in existing wireless systems. The research work is divided into two main topics: 1) adaptive cooperative wireless systems with variable-rate transmission, and 2) cooperative wireless systems with a power consumption constraint. The first topic investigates how the spectral efficiency of cooperative wireless communication systems can be improved while maintaining the QoS in terms of bit error rate and outage probability. The spectral efficiency enhancement is achieved by using three techniques: adaptivity over the relay node (i.e., relay node is active or not), adaptivity over the modulation mode, and relay selection. Based on that, we propose several adaptive cooperative schemes for both the decode-and-forward (DF) and amplify-and-forward (AF) protocols. To evaluate these schemes, we provide performance analysis in terms of average spectral efficiency, average bit error rate (ABER), and outage probability over Rayleigh fading channels. We start with the single-relay cooperative system using DF protocol, in which two adaptive cooperative schemes with variable-rate transmission are proposed. The first scheme, called the minimum error rate scheme (MERS), aims to exploit the transmit diversity to improve the bit error rate. By trading the multiplexing gain against the diversity gain, we propose the second scheme, called the maximum spectral efficiency scheme (MSES), in which cooperative transmission is avoided whenever it is not beneficial. The MERS improves the ABER significantly and achieves equal or better average spectral efficiency compared to the fixed (i.e., non-adaptive) relaying scheme. In contrast, the MSES provides the best average spectral efficiency due to its ability to not only adapt to the channel variation but also to switch between cooperative and non-cooperative transmissions. To further increase the spectral efficiency, we then propose the third scheme, called variable-rate based relay selection (VRRS) scheme, in which a relay node is selected from among the available relay nodes, based on a predefined criterion. Furthermore, we propose two AF adaptive cooperative schemes, mainly to enhance the spectral efficiency. In the first scheme, we introduce a generalized switching policy (GSP) for a single-relay cooperative wireless system that exploits the variable-rate transmission and useful cooperative regions. The second scheme, called the AF efficient relay selection (AFERS) scheme, extends the GSP to also consider the relay selection technique. Analytical and simulation results verify that the AFERS scheme not only outperforms conventional direct transmission in terms of the average spectral efficiency, but also the AF fixed relaying and the outage-based AF adaptive cooperative scheme. The second topic investigates the fair power consumption of the relay nodes for AF cooperative wireless communication systems. The fairness is defined as to achieve equal power consumption over the relay nodes. We focus on how the relay selection process can be controlled in a distributed manner so that the power consumption of the relay nodes can be included in relay selection. We first introduce a simple closed-form expression for the weight coefficient used in order to achieve the considered fairness that depends only on the local average channel conditions of the relay path. We then derive closed-form expressions of the weighted outage probability and ABER and show that our proposed strategy not only has less complexity than the conventional centralized one but also provides better accuracy in distributing the total consumed power equally among the relay nodes without affecting the performance.

Author: Praveen Kumar Devulapalli
Publisher: CRC Press
ISBN: 1040051561
Category : Computers
Languages : en
Pages : 123

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Book Description
This book covers wireless cooperative communication and advanced communication techniques for research scholars and post-graduate students. Features: • This book will be the reference book for cooperative communication. • It addresses the problems in small-scale cooperative communication. • It presents cooperative routing algorithms for large-scale cooperative networks with the constraint of throughput and transmission time. • It presents energy- efficient transmission approach by making use of multiple radio terminals. • It presents adaptive routing algorithm for large-scale cooperative network under mobility environment.

Author: Hemanta Kumar Sahu
Publisher:
ISBN: 9789999315715
Category : Technology & Engineering
Languages : en
Pages : 0

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Diving into the cutting-edge realm of wireless communication, "Harvesting Signals" offers a meticulous exploration of the synergistic potential between cooperative communication, Space Shift Keying (SSK) modulation, and Radio Frequency (RF) energy harvesting. In a landscape where the demand for efficient wireless networks is ever-growing, this book presents a groundbreaking investigation into the fusion of cooperative strategies with advanced modulation techniques, promising not only enhanced spectral efficiency but also sustainable energy utilization through RF energy harvesting. Authored by leading experts in the field, this comprehensive analysis delves into the theoretical foundations, practical implementations, and performance evaluations of cooperative communication systems employing SSK modulation and RF energy harvesting. Through a blend of rigorous mathematical frameworks and practical insights, readers are guided through the intricacies of system design, resource allocation, and optimization strategies. From theoretical derivations to real-world experimentation, "Harvesting Signals" offers a roadmap for researchers, engineers, and students alike to navigate the complexities of next-generation wireless networks. Whether seeking to optimize spectral efficiency, extend network lifetime, or minimize energy consumption, this book serves as an indispensable resource in unlocking the full potential of cooperative communication combined with SSK modulation and RF energy harvesting. Prepare to embark on a journey into the forefront of wireless communication research, where innovation meets sustainability, and where the pursuit of performance leads to the harvesting of signals.