Implementing a Cooperative MAC Protocol on GNU Radio PDF Download

Author: Xiaofang Liu
Publisher:
ISBN: 9781109686654
Category :
Languages : en
Pages : 55

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Book Description
In this thesis, we design the details of a cooperative communication protocol on Media Access Control (MAC) layer, and implement the protocol on a Software Defined Radio (SDR) platform. Our protocol is based on Load-Adaptive MAC (LA-MAC), a hybrid protocol of Carrier Sense Multiple Access (CSMA) and Time Division Multiple Access (TDMA), for collision avoidance. We also modified LAMAC to make it compatible with our protocol. Our SDR contains Universal Software Radio Peripheral (USRP), with one motherboard for baseband processing and two daughter boards for sending and receiving processing respectively, and personal computer with Linux system, and they are connected by USB 2.0. We implement the protocol on GNU Radio platform, which is a collection of software that performs as the interface between the hardware radio and higher level software application. Our protocol is developed with C++ and Python. Through experiment results, we demonstrate that the transmission performance is improved after applying the cooperative communication protocol to the system.

Author: Xilin Bai
Publisher:
ISBN:
Category :
Languages : en
Pages : 43

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Book Description
In conventional point-to-point wireless communication, wireless channels may suffer from multipath fading, in which signal attenuation can vary significantly over the course of a given transmission, and thus communication between transmitter and receiver is vulnerable. In recent years, a new paradigm of cooperative communication was proposed and had become a heated topic in the design of wireless networks, such as cellular networks and wireless ad hoc networks. The basic idea lies in cooperative communication is that individual mobile users in wireless networks help each other to send signals to the destination cooperatively. The destination jointly detects multiple copies of the received signals from different cooperative users. Due to the cooperative diversity, the joint detection of the combined signals can be more reliable, and system performance as well as robustness can be significantly improved. The user who helps others forward the information is called a relay. According to the functions of the relay, there are two kinds of cooperative protocols: the relay may first decode the received information and then forward it to the destination as called decode-and-forward (DF) cooperative protocol, or the relay may simply amplify the received signal and forward it as called amplify-and-forward (AF) cooperation protocol. The aim of this thesis research is to implement the DF cooperative communication system based on GNU Radio and Universal Software Radio Peripheral (USRP). Specifically, we focus on a two-user cooperation scheme, one serves as the source node, while the other can be the relay node. The experiments of this model are carried out on GNU Radio, an open-source software development toolkit, and USRPs, computer-hosted software radios. To measure the experiments results, the packet-error-rate (PER) performance analysis is provided for cooperative communications in wireless networks with different configurations, such as various relay positioning, power allocation, payload length and experiment environment. From the simulation results, we can see that the location of the relay plays a critical role in the performance of cooperative communication. The closer the relay to the source, the more transmitter power is preserved; while the closer the relay to the destination, the more receiver power is kept. It is observed that laying the relay near around midpoint of the source and destination will achieve the best cooperative performance. Regarding various power allocation, in a certain low power range, the larger the power is, the better the transmission performance is. However, beyond this power range, different as expected, the less the power is, the better result there will be. This could possibly be caused by the limitation of the amplifier in the USRP boards. Furthermore, with regard to different payload length, the longer the packet is, the more possibilities that the packet is decoded wrong. Finally, tests in different environment show that no matter inside a room, in the narrow hall way, or in open space, the above transmission trend turns out to be the same. The main contribution of the thesis lies in: First, the implementation of the channel estimation based on GNU Radio and USRPs; Second, the design of packet format in order to implement the DF cooperation systems; Third, the implementation of the maximum ratio combing (MRC) and joint decode at the destination. In this research project, we achieve the goal of implementing the DF cooperative communication protocols on the platform of GNU Radio and USRPs, verifying the theoretical performance in books, and learning from experiment results under different scenarios and contributing to the design of DF cooperative communication systems.

Author: Vicente Casares-Giner
Publisher: Springer
ISBN: 3642230415
Category : Computers
Languages : en
Pages : 313

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Book Description
This book constitutes the refereed post-conference proceedings of four workshops colocated with NETWORKING 2011, held in Valencia, Spain, in May 2011: the Workshop on Performance Evaluation of Cognitive Radio Networks: From Theory to Reality, PE-CRN 2011, the Network Coding Applications and Protocols Workshop, NC-Pro 2011, the Workshop on Wireless Cooperative Network Security, WCNS 2011, and the Workshop on Sustainable Networking, SUNSET 2011. The 28 revised full papers presented were carefully reviewed and selected from numerous submissions. The papers cover a wide range of topics addressing the main research efforts in the fields of network coding, sustainable networking, security in wireless cooperative networks, and performance evaluation of cognitive radio networks.

Author: Gesley Abraham George
Publisher:
ISBN:
Category : Computer network protocols
Languages : en
Pages : 42

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Book Description
Abstract: "Software-Defined Radio (SDR) is considered to be the next step in radio communications. Traditional radio systems are limited in capability as they operate in only certain frequency bands using fixed modulation schemes, since the signal processing is handled by customized non-reconfigurable hardware. This restricts devices to understanding only specific communication standards. SDRs do away with such restrictions as they use a combination of reconfigurable hardware and software to do signal processing. This unleashes the potential to operate in any frequency band using any modulation scheme and hence allow radios to understand multiple wireless communication standards. Wireless data communication systems require regulated access to the shared communication media. Medium Access Control (MAC) protocols provide this service. In this thesis, we explore a platform for developing MAC protocols for the GNU Radio open SDR project. The GNU Radio is a collection of software combined with minimal generic hardware -- the Universal Software Radio Peripheral (USRP) that allows construction of software radios. Though GNU Radio relies on software based signal processing, its architecture is unsuitable for developing MAC protocols. We identify the Click software router as a suitable platform for developing MAC protocols for GNU Radio and develop an environment for using GNU Radio signal processing blocks in Click. Further, we implement a simple TDMA protocol as a proof of concept for developing MAC protocols using Click and GNU Radio."

Author: Lagkas, Thomas D.
Publisher: IGI Global
ISBN: 1466641908
Category : Computers
Languages : en
Pages : 438

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Book Description
Cognitive networks can be crucial for the evolution of future communication systems; however, current trends have indicated major movement in other relevant fields towards the integration of different techniques for the realization of self-aware and self-adaptive communication systems. Evolution of Cognitive Networks and Self-Adaptive Communication Systems overviews innovative technologies combined for the formation of self-aware, self-adaptive, and self-organizing networks. By aiming to inform the research community and the related industry of solutions for cognitive networks, this book is essential for researchers, instructors, and professionals interested in clarifying the latest trends resulting in a unified realization for cognitive networking and communication systems.

Author: Rashvand, Habib F.
Publisher: IGI Global
ISBN: 1466609613
Category : Computers
Languages : en
Pages : 656

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Book Description
Although the existing layering infrastructure--used globally for designing computers, data networks, and intelligent distributed systems and which connects various local and global communication services--is conceptually correct and pedagogically elegant, it is now well over 30 years old has started create a serious bottleneck. Using Cross-Layer Techniques for Communication Systems: Techniques and Applications explores how cross-layer methods provide ways to escape from the current communications model and overcome the challenges imposed by restrictive boundaries between layers. Written exclusively by well-established researchers, experts, and professional engineers, the book will present basic concepts, address different approaches for solving the cross-layer problem, investigate recent developments in cross-layer problems and solutions, and present the latest applications of the cross-layer in a variety of systems and networks.

Author: Magnus Jonsson
Publisher: Springer
ISBN: 3319038710
Category : Computers
Languages : en
Pages : 194

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Book Description
This book constitutes the refereed proceedings of the 6th International Workshop on Multiple Access Communications, MACOM 2013, held in Vilnius, Lithuania, in December 2013. The 16 full papers presented were carefully reviewed and selected from various submissions. They describe the latest advancements in the field of multiple access communications with an emphasis on OFDM techniques, channel coding, spectrum management, medium access control protocols and different aspects of wireless access networks.

Author: Guojun Huang
Publisher:
ISBN:
Category : Cognitive radio networks
Languages : en
Pages : 37

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Book Description
This thesis presents an adaptive MAC (AMAC) protocol for supporting MAC layer adaptation in cognitive radio networks. MAC protocol adaptation is motivated by the exibility of emerging software-de ned radios which make it feasible to dynamically adjust radio protocols and parameters in order to maintain communications quality. Dynamic changes to the MAC layer may be useful in tactical or vehicular networking scenarios, where radio node density, tra c volumes and service requirements can vary widely over time. A speci c control framework for the proposed AMAC algorithm is described based on the "CogNet" protocol stack which uses a Global Control Plane (GCP) to distribute control information between nearby radios. An AMAC prototype which switches between CSMA and TDMA is evaluated for various tra c scenarios using the NS-2 simulator. In addition, a proof-of-concept AMAC is implemented using GNUradio/USRP platforms on the ORBIT radio grid testbed. Detailed simulation and experimental results are given for both UDP and TCP tra c with di erent usage scenarios and application models. The results show that AMAC can provide improved performance relative to a conventional static system and can be implemented with reasonable control protocol overhead and latency.

Author: Rana Azeem M. Khan
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Book Description
Cooperative diversity has emerged as a promising technique to combat fading and improve reliability in a wireless environment. In cooperative diversity protocols, neighboring nodes act as virtual multiple-input-multiple-output (VMIMO) systems, where they cooperate with the transmitter-receiver pair to deliver multiple copies of a packet to the receiver via spatially independent fading channels. These multiple copies of the same packet can be combined at the receiver to recover the original packet. Medium Access Control (MAC) protocols play an important part in realizing this concept by effectively coordinating handshake and transmissions between source, partner and destination nodes. In this thesis, we investigate opportunities for improving reliability in Wireless Sensor Networks using cooperative MAC protocols. First, a Medium Access Control protocol, called CPS-MAC, is proposed. Design challenges such as efficiently waking up neighborhood nodes, minimizing energy overhead, and partner selection are also addressed. Then, Reliable Cooperative Transmission-MAC (RCT-MAC) is proposed which extends the functionality of Cooperative Preamble Sampling-MAC (CPS-MAC) by implementing the Cooperation on Demand concept: nodes cooperate only when needed. Furthermore, RCT-MAC is one of the first attempts to compare the performance of a cooperative Wireless Sensor Network (WSN) MAC protocol against conventional protocols for WSNs namely B-MAC, L-MAC, and IEEE 802.15.4. The reliability vs energy efficiency tradeoff is analyzed for both CPS-MAC and RCT-MAC. Lastly, we evaluate a Packet Error Prediction scheme particularly envisioned for preamble sampling cooperative protocols and meant to supplement traditional partner selection schemes. The correlation between the handshake packets and data packets is analyzed using empirical data. ; eng

Author: Shiwen Mao
Publisher: Springer Science & Business Media
ISBN: 146144957X
Category : Technology & Engineering
Languages : en
Pages : 128

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Book Description
This book focuses on the problem of video streaming over emerging cognitive radio (CR) networks. The book discusses the problems and techniques for scalable video streaming over cellular cognitive radio networks, ad hoc CR networks, cooperative CR networks, and femtocell CR networks. The authors formulate these problems and propose optimal algorithms to solve these problems. Also the book analyzes the proposed algorithms and validates the algorithms with simulations.