This SpringerBrief examines anti-jamming transmissions in cognitive radio networks (CRNs), including several recent related research topics within this field. The author introduces the transmissions based on uncoordinated spread spectrum to address smart jammers in CRNs. The author applies game theory to investigate the interactions between secondary users and jammers while providing game theoretic solutions to suppress jamming incentives in CRNs. Later chapters evaluate the Nash equilibrium and Stackelberg equilibrium of the jamming games under various network scenarios. Professionals and researchers working in networks, wireless communications and information technology will find Anti-Jamming Transmissions in Cognitive Radio Networks valuable material as a reference. Advanced-level students studying electrical engineering and computer science will also find this brief a useful tool.

This monograph is intended for the designers and would-be designers of secure and efficient wireless communication systems under intentional interference. Along with the widespread of wireless devices, especially reconfigurable software defined radios, jamming has become a serious threat to civilian communications. In this book, going beyond traditional communication system design that mainly focuses on accurate information transmission under benign environments, we aim to enhance the physical layer security of communication systems by integrating modern cryptographic techniques into transceiver design, so as to achieve secure high-speed transmission under hostile interference with high reliability and efficiency. We revisit existing jamming patterns, and introduce new jamming patterns. We analyze the weaknesses of existing anti-jamming techniques. We present innovative and feasible anti-jamming techniques, which can strengthen the inherent security of the 3G, 4G and the upcoming 5G systems with minimal and inexpensive changes to the existing CDMA, frequency hopping and OFDM schemes. We also provide benchmarks for system performance evaluation under various jamming scenarios through capacity analysis. This book includes design principles, in-depth theoretical analysis and practical design examples, and will be of interest to academic researchers as well as professionals in industry.

With wireless devices and applications booming, the problem of inefficient utilization of the precious radio spectrum has arisen. Cognitive radio is a key technology to improve spectrum utilization. A major challenge in cognitive radio networks is spectrum sensing, which detects if a spectrum band is being used by a primary user. Spectrum sensing plays a critical role in cognitive radio networks. However, spectrum sensing is vulnerable to security attacks from malicious users. In this dissertation, we propose a malicious user detection scheme, a density based SSDF detection scheme, a conjugate prior based SSDF detection scheme, and an anti-jamming algorithm to achieve robust and secure cooperative spectrum sensing in cognitive radio networks. Performance analysis and simulation results show that our proposed schemes can achieve very good performance in detecting malicious users, excluding abnormal sensing reports, and defending the jamming attack, thus improve spectrum sensing performance in cognitive radio networks.

Cognitive radio technologies are forms of wireless communication with many and varied applications. The contributions in this book will benefit researchers and engineers as they offer cutting-edge knowledge in the field. Subjects include uses of wideband voltage controlled oscillators, control planes for spectrum access and mobility in networks with heterogeneous frequency devices. Other chapters cover cognitive media access control and measurement methods for spectrum occupancy. In addition, there are contributions on delay analysis and channel selection in single-hop networks for delay-sensitive applications, the application of transmission security (TRANSEC) protocols to cognitive radio communication and the use of blind detection, parameters, estimation and the despreading of DS-CDMA signals in multirate, multiuser cognitive radio systems.

Broadcast spectrum is scarce, both in terms of our ability to access existing spectrum and as a result of access rules created by governments. An emerging paradigm called cognitive radio, however, has the potential to allow different systems to dynamically access and opportunistically exploit the same frequency band in an efficient way, thereby allowing broadcasters to use spectrum more efficiently. Cognitive Radio and Interference Management: Technology and Strategy brings together state-of-the-art research results on cognitive radio and interference management from both theoretical and practical perspectives. It serves as a bridge between people who are working to develop theoretical and practical research in cognitive radio and interference management, and therefore facilitate the future development of cognitive radio and its applications.

In this dissertation, I examine the performance of a cognitive radio (CR) system in a hostile environment where an intelligent adversary tries to disrupt communications with a Gaussian noise signal. I analyze a cluster-based network of secondary users (SUs). The adversary can limit access for SUs by either transmitting a spoofing signal in the sensing interval, or a desynchronizing signal in the code acquisition interval. By jamming the network during the transmission interval, the adversary can reduce the rate of successful transmission. In the first part (Chapters 2 and 3), I investigate the optimal strategy for spoofing and jamming to minimize the SU throughput in a generic communication system. I investigate the system performance under attack over slow and fast Rayleigh fading channels. I present how the adversary can optimally allocate power across subcarriers during sensing and transmission intervals with knowledge of the system, using a simple optimization approach. I determine a worst-case optimal-energy allocation for spoofing and jamming, which gives a lower bound to the overall information throughput of SUs under attack. I then extend the analysis to optimal spoofing power allocation for a CR network operating in Nakagami-m fading. The optimized adversary reduces the throughput by a factor of 4 to 5, relative to an adversary who divides power equally across all bands, around 25 dB jamming-to-signal-power ratio (JSR), under slow fading. Under fast fading, the optimized adversary can disrupt the communication at a JSR 10 dB lower than an unoptimized adversary. In the second part (Chapters 4 and 5), I consider the disruptive attacks on a video-transmitting CR network. I investigate the optimal strategy for spoofing, desynchronizing and jamming a cluster based CR network with a Gaussian noise signal. I generalize the optimization approach from Chapter 1 to show how the adversary can optimally allocate its energy across subcarriers during sensing, code acquisition and transmission intervals. I determine a worst-case optimal-energy allocation for spoofing, desynchronizing and jamming, which gives an upper bound to the received video distortion of SUs. I also propose cross-layer resource allocation algorithms and evaluate their performance under disruptive attacks. The optimized adversary can reduce the received video peak-signal-to-noise-ratio up to 5 dB lower than an equal-power adversary, at low JSR.

Cognitive Radio Communications and Networks gives comprehensive and balanced coverage of the principles of cognitive radio communications, cognitive networks, and details of their implementation, including the latest developments in the standards and spectrum policy. Case studies, end-of-chapter questions, and descriptions of various platforms and test beds, together with sample code, give hands-on knowledge of how cognitive radio systems can be implemented in practice. Extensive treatment is given to several standards, including IEEE 802.22 for TV White Spaces and IEEE SCC41 Written by leading people in the field, both at universities and major industrial research laboratories, this tutorial text gives communications engineers, R&D engineers, researchers, undergraduate and post graduate students a complete reference on the application of wireless communications and network theory for the design and implementation of cognitive radio systems and networks - Each chapter is written by internationally renowned experts, giving complete and balanced treatment of the fundamentals of both cognitive radio communications and cognitive networks, together with implementation details - Extensive treatment of the latest standards and spectrum policy developments enables the development of compliant cognitive systems - Strong practical orientation – through case studies and descriptions of cognitive radio platforms and testbeds – shows how real world cognitive radio systems and network architectures have been built Alexander M. Wyglinski is an Assistant Professor of Electrical and Computer Engineering at Worcester Polytechnic Institute (WPI), Director of the WPI Limerick Project Center, and Director of the Wireless Innovation Laboratory (WI Lab) - Each chapter is written by internationally renowned experts, giving complete and balanced treatment of the fundamentals of both cognitive radio communications and cognitive networks, together with implementation details - Extensive treatment of the latest standards and spectrum policy developments enables the development of compliant cognitive systems - Strong practical orientation – through case studies and descriptions of cognitive radio platforms and testbeds – shows how "real world" cognitive radio systems and network architectures have been built