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Wireless networks

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Full-Text Articles in Physical Sciences and Mathematics

Performance Analysis And Comparison Of Nonideal Wireless Pbft And Raft Consensus Networks In 6g Communications, Haoxiang Luo, Xiangyue Yang, Hongfang Yu, Gang Sun, Bo Lei, Mohsen Guizani Oct 2023

Performance Analysis And Comparison Of Nonideal Wireless Pbft And Raft Consensus Networks In 6g Communications, Haoxiang Luo, Xiangyue Yang, Hongfang Yu, Gang Sun, Bo Lei, Mohsen Guizani

Machine Learning Faculty Publications

Due to advantages in security and privacy, blockchain is considered a key enabling technology to support 6G communications. Practical Byzantine Fault Tolerance (PBFT) and RAFT are seen as the most applicable consensus mechanisms (CMs) in blockchain-enabled wireless networks. However, previous studies on PBFT and RAFT rarely consider the channel performance of the physical layer, such as path loss and channel fading, resulting in research results that are far from real networks. Additionally, 6G communications will widely deploy high-frequency signals such as terahertz (THz) and millimeter wave (mmWave), while performances of PBFT and RAFT are still unknown when these signals are …


Agris: Wind-Adaptive Wideband Reconfigurable Intelligent Surfaces For Resilient Wireless Agricultural Networks At Millimeter-Wave Spectrum, Shuai Nie, M. C. Vuran Jun 2023

Agris: Wind-Adaptive Wideband Reconfigurable Intelligent Surfaces For Resilient Wireless Agricultural Networks At Millimeter-Wave Spectrum, Shuai Nie, M. C. Vuran

School of Computing: Faculty Publications

Wireless networks in agricultural environments are unique in many ways. Recent measurements reveal that the dynamics of crop growth impact wireless propagation channels with a long-term seasonal pattern. Additionally, short-term environmental factors, such as strong wind, result in variations in channel statistics. Next-generation agricultural fields, populated by autonomous tractors, drones, and high-throughput sensing systems, require high-throughput connectivity infrastructure, resulting in the future deployment of high-frequency networks, where they have not been deployed before. More specifically, when millimeter-wave (mmWave) communication systems, a viable candidate for 5G and 6G high-throughput solutions, are deployed for higher throughput, these issues become more prominent due …


Joint Congestion And Contention Avoidance In A Scalable Qos-Aware Opportunistic Routing In Wireless Ad-Hoc Networks, Ali Parsa, Neda Moghim, Sasan Haghani Jan 2023

Joint Congestion And Contention Avoidance In A Scalable Qos-Aware Opportunistic Routing In Wireless Ad-Hoc Networks, Ali Parsa, Neda Moghim, Sasan Haghani

VMASC Publications

Opportunistic routing (OR) can greatly increase transmission reliability and network throughput in wireless ad-hoc networks by taking advantage of the broadcast nature of the wireless medium. However, network congestion is a barrier in the way of OR's performance improvement, and network congestion control is a challenge in OR algorithms, because only the pure physical channel conditions of the links are considered in forwarding decisions. This paper proposes a new method to control network congestion in OR, considering three types of parameters, namely, the backlogged traffic, the traffic flows' Quality of Service (QoS) level, and the channel occupancy rate. Simulation results …


Randomized Algorithms For Resource Allocation In Device To Device Communication., Subhankar Ghosal Dr. Dec 2022

Randomized Algorithms For Resource Allocation In Device To Device Communication., Subhankar Ghosal Dr.

Doctoral Theses

In device to device (D2D) communication, two users residing in close proximity can directly communicate between them, through a common channel, without the need of a base station. A pair of D2D users forms a link and a channel needs to be allocated to it. The interference relationship among the active links at time t is modelled as an interference graph g(t). To establish interference-free communication, we have to assign a channel vector C(t) and a power vector corresponding to the active links such that the required signal to interference plus noise ratio (SINR) is satisfied for each link. Since …


Artificial Intelligence For Natural Disaster Management, Guansong Pang Nov 2022

Artificial Intelligence For Natural Disaster Management, Guansong Pang

Research Collection School Of Computing and Information Systems

Artificial intelligence (AI) can leverage massive amount of diverse types of data, such as geospatial data, social media data, and wireless network sensor data, to enhance our understanding of natural disasters, their forecasting and detection, and humanitarian assistance in natural disaster management (NDM). Due to this potential, different communities have been dedicating enormous efforts to the development and/or adoption of AI technologies for NDM. This article provides an overview of these efforts and discusses major challenges and opportunities in this topic.


Green, Quantized Federated Learning Over Wireless Networks: An Energy-Efficient Design, Minsu Kim, Walid Saad, Mohammad Mozaffari, Mérouane Debbah Jul 2022

Green, Quantized Federated Learning Over Wireless Networks: An Energy-Efficient Design, Minsu Kim, Walid Saad, Mohammad Mozaffari, Mérouane Debbah

Machine Learning Faculty Publications

The practical deployment of federated learning (FL) over wireless networks requires balancing energy efficiency and convergence time due to the limited available resources of devices. Prior art on FL often trains deep neural networks (DNNs) to achieve high accuracy and fast convergence using 32 bits of precision level. However, such scenarios will be impractical for resource-constrained devices since DNNs typically have high computational complexity and memory requirements. Thus, there is a need to reduce the precision level in DNNs to reduce the energy expenditure. In this paper, a green-quantized FL framework, which represents data with a finite precision level in …


Pervasive Machine Learning For Smart Radio Environments Enabled By Reconfigurable Intelligent Surfaces, George C. Alexandropoulos, Kyriakos Stylianopoulos, Chongwen Huang, Chau Yuen, Mehdi Bennis, Mérouane Debbah May 2022

Pervasive Machine Learning For Smart Radio Environments Enabled By Reconfigurable Intelligent Surfaces, George C. Alexandropoulos, Kyriakos Stylianopoulos, Chongwen Huang, Chau Yuen, Mehdi Bennis, Mérouane Debbah

Machine Learning Faculty Publications

The emerging technology of Reconfigurable Intelligent Surfaces (RISs) is provisioned as an enabler of smart wireless environments, offering a highly scalable, low-cost, hardware-efficient, and almost energy-neutral solution for dynamic control of the propagation of electromagnetic signals over the wireless medium, ultimately providing increased environmental intelligence for diverse operation objectives. One of the major challenges with the envisioned dense deployment of RISs in such reconfigurable radio environments is the efficient configuration of multiple metasurfaces with limited, or even the absence of, computing hardware. In this paper, we consider multi-user and multi-RIS-empowered wireless systems, and present a thorough survey of the online …


Efficient Handover Mechanisms For Heterogeneous Networks., Shankar Kumar Ghosh Dr. Apr 2022

Efficient Handover Mechanisms For Heterogeneous Networks., Shankar Kumar Ghosh Dr.

Doctoral Theses

In this thesis, some analytical frameworks have been developed to analyze the effect of different system parameters on handover performances in heterogeneous network (HetNet) and based on such frameworks, some efficient handover algorithms have been proposed. The study starts with an analytical framework to investigate the effect of resource allocation mechanisms, upper layer mobility management protocols (MMPs) and handover decision metrics on user perceived throughput. This analysis reveals that among other factors, handover decision metric plays a crucial role in determining user perceived throughput in HetNet. Subsequently, we develop two handover decision metrics for ultra dense networks (UDN) and unlicensed …


Industrial Digital Twins At The Nexus Of Nextg Wireless Networks And Computational Intelligence: A Survey, Shah Zeb, Aamir Mahmood, Syed Ali Hassan, Md. Jalil Piran, Mikael Gidlund, Mohsen Guizani Apr 2022

Industrial Digital Twins At The Nexus Of Nextg Wireless Networks And Computational Intelligence: A Survey, Shah Zeb, Aamir Mahmood, Syed Ali Hassan, Md. Jalil Piran, Mikael Gidlund, Mohsen Guizani

Machine Learning Faculty Publications

By amalgamating recent communication and control technologies, computing and data analytics techniques, and modular manufacturing, Industry 4.0 promotes integrating cyber–physical worlds through cyber–physical systems (CPS) and digital twin (DT) for monitoring, optimization, and prognostics of industrial processes. A DT enables interaction with the digital image of the industrial physical objects/processes to simulate, analyze, and control their real-time operation. DT is rapidly diffusing in numerous industries with the interdisciplinary advances in the industrial Internet of things (IIoT), edge and cloud computing, machine learning, artificial intelligence, and advanced data analytics. However, the existing literature lacks in identifying and discussing the role and …


Defensive Distillation-Based Adversarial Attack Mitigation Method For Channel Estimation Using Deep Learning Models In Next-Generation Wireless Networks, Ferhat Ozgur Catak, Murat Kuzlu, Evren Catak, Umit Cali, Ozgur Guler Jan 2022

Defensive Distillation-Based Adversarial Attack Mitigation Method For Channel Estimation Using Deep Learning Models In Next-Generation Wireless Networks, Ferhat Ozgur Catak, Murat Kuzlu, Evren Catak, Umit Cali, Ozgur Guler

Engineering Technology Faculty Publications

Future wireless networks (5G and beyond), also known as Next Generation or NextG, are the vision of forthcoming cellular systems, connecting billions of devices and people together. In the last decades, cellular networks have dramatically grown with advanced telecommunication technologies for high-speed data transmission, high cell capacity, and low latency. The main goal of those technologies is to support a wide range of new applications, such as virtual reality, metaverse, telehealth, online education, autonomous and flying vehicles, smart cities, smart grids, advanced manufacturing, and many more. The key motivation of NextG networks is to meet the high demand for those …


Different Approximation Algorithms For Channel Scheduling In Wireless Networks, Qiufen Ni, Chuanhe Huang, Panos M. Pardalos, Jia Ye, Bin Fu Nov 2020

Different Approximation Algorithms For Channel Scheduling In Wireless Networks, Qiufen Ni, Chuanhe Huang, Panos M. Pardalos, Jia Ye, Bin Fu

Computer Science Faculty Publications and Presentations

We introduce a new two-side approximation method for the channel scheduling problem, which controls the accuracy of approximation in two sides by a pair of parameters . We present a series of simple and practical-for-implementation greedy algorithms which give constant factor approximation in both sides. First, we propose four approximation algorithms for the weighted channel allocation problem: 1. a greedy algorithm for the multichannel with fixed interference radius scheduling problem is proposed and an one side -IS-approximation is obtained; 2. a greedy -approximation algorithm for single channel with fixed interference radius scheduling problem is presented; 3. we improve the existing …


Blind Separation For Intermittent Sources Via Sparse Dictionary Learning, Annan Dong May 2019

Blind Separation For Intermittent Sources Via Sparse Dictionary Learning, Annan Dong

Dissertations

Radio frequency sources are observed at a fusion center via sensor measurements made over slow flat-fading channels. The number of sources may be larger than the number of sensors, but their activity is sparse and intermittent with bursty transmission patterns. To account for this, sources are modeled as hidden Markov models with known or unknown parameters. The problem of blind source estimation in the absence of channel state information is tackled via a novel algorithm, consisting of a dictionary learning (DL) stage and a per-source stochastic filtering (PSF) stage. The two stages work in tandem, with the latter operating on …


A Comprehensive Methodology To Evaluate The Performance Of A Cooperative Wireless Network, Aykut Kalaycioğlu, Ahmet Akbulut, Asim Egemen Yilmaz, Di̇lek Arslan Jan 2019

A Comprehensive Methodology To Evaluate The Performance Of A Cooperative Wireless Network, Aykut Kalaycioğlu, Ahmet Akbulut, Asim Egemen Yilmaz, Di̇lek Arslan

Turkish Journal of Electrical Engineering and Computer Sciences

Performance evaluation of a cooperative wireless communication network depends on several parameters. Many of the studies, in fact, take a limited number of performance metrics individually to reach a conclusion about the performance of a network. Besides, in general, some performance metrics might be in conflict. Thus, ignoring the combined effect of all performance criteria in the network may lead to an incorrect conception of the overall communication performance of the network. Therefore, in this study, a comprehensive evaluation methodology in terms of various metrics is proposed to calculate the performance of a cooperative wireless communication network deployment using a …


Towards Dynamically Monitoring Android Applications On Non-Rooted Devices In The Wild, Xiaoxiao Tang, Daoyuan Wu, Yan Lin, Debin Gao Jun 2018

Towards Dynamically Monitoring Android Applications On Non-Rooted Devices In The Wild, Xiaoxiao Tang, Daoyuan Wu, Yan Lin, Debin Gao

Research Collection School Of Computing and Information Systems

Dynamic analysis is an important technique to reveal sensitive behavior of Android apps. Current works require access to the code-level and system-level events (e.g., API calls and system calls) triggered by the running apps and consequently they can only be conducted on in-lab running environments (e.g., emulators and modified OS). The strict requirement of running environment hinders their deployment in scale and makes them vulnerable to anti-analysis techniques. Furthermore, current dynamic analysis of Android apps exploits input generators to invoke app behavior, which, however, cannot provide sufficient code coverage. We propose to dynamically analyze app behavior on non-rooted devices used …


Leveraging Resources On Anonymous Mobile Edge Nodes, Ahmed Salem Apr 2018

Leveraging Resources On Anonymous Mobile Edge Nodes, Ahmed Salem

Computer Science Theses & Dissertations

Smart devices have become an essential component in the life of mankind. The quick rise of smartphones, IoTs, and wearable devices enabled applications that were not possible few years ago, e.g., health monitoring and online banking. Meanwhile, smart sensing laid the infrastructure for smart homes and smart cities. The intrusive nature of smart devices granted access to huge amounts of raw data. Researchers seized the moment with complex algorithms and data models to process the data over the cloud and extract as much information as possible. However, the pace and amount of data generation, in addition to, networking protocols transmitting …


Passive Radiolocation Of Ieee 802.11 Emitters Using Directional Antennae, Bradford E. Law Mar 2018

Passive Radiolocation Of Ieee 802.11 Emitters Using Directional Antennae, Bradford E. Law

Theses and Dissertations

Low-cost commodity hardware and cheaper, more capable consumer-grade drones make the threat of home-made, inexpensive drone-mounted wireless attack platforms (DWAPs) greater than ever. Fences and physical security do little to impede a drone from approaching private, commercial, or government wireless access points (WAPs) and conducting wireless attacks. At the same time, unmanned aerial vehicles (UAVs) present a valuable tool for network defenders conducting site surveys and emulating threats. These platforms present near-term dangers and opportunities for corporations and governments. Despite the vast leaps in technology these capabilities represent, UAVs are noisy and consequently difficult to conceal as they approach a …


Application Of 3d Delaunay Triangulation In Fingerprint Authentication System, Wencheng Yang, Ahmed Ibrahim, Junaid Chaudhry, Song Wang, Jiankun Hu, Craig Valli Jan 2018

Application Of 3d Delaunay Triangulation In Fingerprint Authentication System, Wencheng Yang, Ahmed Ibrahim, Junaid Chaudhry, Song Wang, Jiankun Hu, Craig Valli

Research outputs 2014 to 2021

Biometric security has found many applications in Internet of Things (IoT) security. Many mobile devices including smart phones have supplied fingerprint authentication function. However, the authentication performance in such restricted environment has been downgraded significantly. A number of methods based on Delaunay triangulation have been proposed for minutiae-based fingerprint matching, due to some favorable properties of the Delaunay triangulation under image distortion. However, all existing methods are based on 2D pattern, of which each unit, a Delaunay triangle, can only provide limited discrimination ability and could cause low matching performance. In this paper, we propose a 3D Delaunay triangulation based …


Applying Machine Learning To Advance Cyber Security: Network Based Intrusion Detection Systems, Hassan Hadi Latheeth Al-Maksousy Jan 2018

Applying Machine Learning To Advance Cyber Security: Network Based Intrusion Detection Systems, Hassan Hadi Latheeth Al-Maksousy

Computer Science Theses & Dissertations

Many new devices, such as phones and tablets as well as traditional computer systems, rely on wireless connections to the Internet and are susceptible to attacks. Two important types of attacks are the use of malware and exploiting Internet protocol vulnerabilities in devices and network systems. These attacks form a threat on many levels and therefore any approach to dealing with these nefarious attacks will take several methods to counter. In this research, we utilize machine learning to detect and classify malware, visualize, detect and classify worms, as well as detect deauthentication attacks, a form of Denial of Service (DoS). …


Towards Using Certificate-Based Authentication As A Defense Against Evil Twins In 802.11 Networks, Travis S. Hendershot Nov 2016

Towards Using Certificate-Based Authentication As A Defense Against Evil Twins In 802.11 Networks, Travis S. Hendershot

Theses and Dissertations

Wireless clients are vulnerable to exploitation by evil twins due to flaws in the authentication process of 802.11 Wi-Fi networks. Current certificate-based wireless authentication protocols present a potential solution, but are limited in their ability to provide a secure and usable platform for certificate validation. Our work seeks to mitigate these limitations by exploring a client-side strategy for utilizing alternative trust models in wireless network authentication. We compile a taxonomy of various trust models for conducting certificate-based authentication of wireless networks and methodically evaluate each model according to desirable properties of security, usability, and deployability. We then build a platform …


Stpp: Spatial-Temporal Phase Profiling Based Method For Relative Rfid Tag Localization, Longfei Shangguan, Zheng Yang, Alex X. Liu, Zimu Zhou, Yunhao Liu Jul 2016

Stpp: Spatial-Temporal Phase Profiling Based Method For Relative Rfid Tag Localization, Longfei Shangguan, Zheng Yang, Alex X. Liu, Zimu Zhou, Yunhao Liu

Research Collection School Of Computing and Information Systems

Many object localization applications need the relative locations of a set of objects as oppose to their absolute locations. Although many schemes for object localization using radio frequency identification (RFID) tags have been proposed, they mostly focus on absolute object localization and are not suitable for relative object localization because of large error margins and the special hardware that they require. In this paper, we propose an approach called spatial-temporal phase profiling (STPP) to RFID-based relative object localization. The basic idea of STPP is that by moving a reader over a set of tags during which the reader continuously interrogating …


Application Of Combinatorial Structures In Wireless Communication., Samiran Bag Dr. Jan 2016

Application Of Combinatorial Structures In Wireless Communication., Samiran Bag Dr.

Doctoral Theses

Wireless communication has a compelling need in today’s world. This need is driven by the sudden surge in the demand of ad-hoc networks like wireless sensor networks. These networks consist of many isolated devices called nodes that use the wireless medium for communication. There are three security notions attached to any wireless communication. These are data confidentiality, data integrity and data availability. Cryptographic protocols are required for achieving the first two notions which in turn require shared secret keys. The last notion viz. data availability mainly deals with protecting the data from ‘denial of service attack’.In this thesis, we apply …


Wireless Location Determination: Using Existing 802.11 Wireless Networks To Determine A Users Location, Travis Calvert Aug 2014

Wireless Location Determination: Using Existing 802.11 Wireless Networks To Determine A Users Location, Travis Calvert

Journal of Undergraduate Research at Minnesota State University, Mankato

The ability to determine a user’s location through an existing 802.11 wireless network has vast implications in the area of context-aware and pervasive computing. Such abilities have been developed mainly in the Linux environment to date. To maximize its usefulness, a location determination system was developed for the more dominant Windows operation system. While being able to operate outdoors as well as indoors, this system succeeds where traditional GPS (Global Positioning Systems) fail, namely indoor environments. This system could benefit the large number of existing wireless networks and requires no additional hardware; only a few simple software downloads. The ability …


Coverage And Detection In Wireless Sensor Networks., Mrinal Nandi Dr. Feb 2014

Coverage And Detection In Wireless Sensor Networks., Mrinal Nandi Dr.

Doctoral Theses

A Wireless Sensor Networks (WSNs), which are two or three dimensional systems, usually consist of a large number of small sensors equipped with some processing circuit, and a wireless transceiver. The sensors have small size, low battery capacity, non-renewable power supply, small processing power, limited buffer capacity and low-power radio. They may measure distance, direction, speed, humidity, wind speed, soil makeup, temperature, chemicals, light, and various other parameters. The sensors are autonomous devices with integrated sensing, processing, and communication capabilities.In this thesis, we consider ‘coverage problem’ and ‘detection problem’ in Wireless Sensor Networks (WSNs) in grid as well as in …


Wireless Sensor Localization Using Enhanced Dv-Aoa Algorithm, Peter Brida, Juraj Machaj, Jozef Benikovsky Jan 2014

Wireless Sensor Localization Using Enhanced Dv-Aoa Algorithm, Peter Brida, Juraj Machaj, Jozef Benikovsky

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we deal with the improvement of the positioning accuracy of distance vector (DV)-based positioning algorithms, which use angular information DV- angle of arrival (AoA). This algorithm belongs to an ad-hoc positioning system. We focus on the improvement of the algorithm and its enhanced version is presented. The angular information of particular nodes is obtained and processed by the original algorithm; however, the final position estimation is determined by the proposed novel algorithm using only a subset of all intersections. We assign weights to the individual intersections according to their positions and the positions of the RNs. For …


Fault Tolerant Broadcasting Analysis In Wireless Monitoring Networks, Akbar Ghaffarpour Rahbar Jan 2014

Fault Tolerant Broadcasting Analysis In Wireless Monitoring Networks, Akbar Ghaffarpour Rahbar

Turkish Journal of Electrical Engineering and Computer Sciences

Wireless monitoring networks can be used for security applications such as the monitoring of narrow passages and operational fields. These networks can be designed based on sensor networks. In sensor networks, each node can hear a message and broadcast the message to its neighbor nodes. Nevertheless, nodes may fail, so that faulty nodes cannot hear or cannot transmit any message, where the locations of the faulty nodes are unknown and their failures are permanent. In this paper, the nodes are situated on a line or a square grid-based topology in a plane for security/monitoring applications. For each topology, 2 nonadaptive …


Horizontal Dilution Of Precision-Based Ultra-Wideband Positioning Technique For Indoor Environments, Kerem Küçük Jan 2014

Horizontal Dilution Of Precision-Based Ultra-Wideband Positioning Technique For Indoor Environments, Kerem Küçük

Turkish Journal of Electrical Engineering and Computer Sciences

Ultra-wideband (UWB) technology provides considerable performance in many indoor localization problems thanks to its very wide spectrum and high-resolution characteristics. In this paper, we propose using the horizontal dilution of precision (HDOP) to decrease the localization error in indoor environments for UWB localization systems. To achieve this aim, first we determine the positioning accuracy of a commercially available UWB positioning system using laboratory experiments. Next, the results of the position estimations obtained by the HDOP are compared with the experimental results acquired by the UWB positioning system. Finally, we investigate a detailed comparison with the least squares (LS), nonlinear regression …


A Distributed Consensus Algorithm For Decision Making In Service-Oriented Internet Of Things, Shancang Li, George Oikonomou, Theo Tryfonas, Thomas M. Chen, Li Da Xu Jan 2014

A Distributed Consensus Algorithm For Decision Making In Service-Oriented Internet Of Things, Shancang Li, George Oikonomou, Theo Tryfonas, Thomas M. Chen, Li Da Xu

Information Technology & Decision Sciences Faculty Publications

In a service-oriented Internet of things (IoT) deployment, it is difficult to make consensus decisions for services at different IoT edge nodes where available information might be insufficient or overloaded. Existing statistical methods attempt to resolve the inconsistency, which requires adequate information to make decisions. Distributed consensus decision making (CDM) methods can provide an efficient and reliable means of synthesizing information by using a wider range of information than existing statistical methods. In this paper, we first discuss service composition for the IoT by minimizing the multi-parameter dependent matching value. Subsequently, a cluster-based distributed algorithm is proposed, whereby consensuses are …


Does Your Wireless Lan Have Criminal Intent?, Michael Crowley, Andrew Woodward Nov 2013

Does Your Wireless Lan Have Criminal Intent?, Michael Crowley, Andrew Woodward

Michael Crowley

All of the literature relating to wireless network security has focused on the flaws, newer alternatives and suggestions for securing the network. There is much speculation and anecdotal statements in relation to what can happen if a breach occurs, but this is mostly from a computer security perspective, and mostly expressed in terms of potential for financial loss. This paper examines the potential legal ramifications of failing to properly secure a wireless network. Several scenarios are examined within based on usage of wireless on the various category of attack. Legal opinion, backed up with case law, is provided for each …


Necessary And Sufficient Informativity Conditions For Robust Network Reconstruction Using Dynamical Structure Functions, Vasu Nephi Chetty Dec 2012

Necessary And Sufficient Informativity Conditions For Robust Network Reconstruction Using Dynamical Structure Functions, Vasu Nephi Chetty

Theses and Dissertations

Dynamical structure functions were developed as a partial structure representation of linear time-invariant systems to be used in the reconstruction of biological networks. Dynamical structure functions contain more information about structure than a system's transfer function, while requiring less a priori information for reconstruction than the complete computational structure associated with the state space realization. Early sufficient conditions for network reconstruction with dynamical structure functions severely restricted the possible applications of the reconstruction process to networks where each input independently controls a measured state. The first contribution of this thesis is to extend the previously established sufficient conditions to incorporate …


Wispernet: Anti-Jamming For Wireless Sensor Networks, Miroslav Pajic, Rahul Mangharam Oct 2012

Wispernet: Anti-Jamming For Wireless Sensor Networks, Miroslav Pajic, Rahul Mangharam

Rahul Mangharam

Resilience to electromagnetic jamming and its avoidance are difficult problems. It is often both hard to distinguish malicious jamming from congestion in the broadcast regime and a challenge to conceal the activity patterns of the legitimate communication protocol from the jammer. In the context of energy-constrained wireless sensor networks, nodes are scheduled to maximize the common sleep duration and coordinate communication to extend their battery life. This results in well-defined communication patterns with possibly predictable intervals of activity that are easily detected and jammed by a statistical jammer. We present an anti-jamming protocol for sensor networks which eliminates spatio-temporal patterns …