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Communication Technology In The Military, Jordan Diehl 2013 Bridgewater College

Communication Technology In The Military, Jordan Diehl

Senior Seminars

No abstract provided.


Detecting Point-Like Sources Of Unknown Frequency Spectra, Raffaele Solimene, Giuseppe Ruvio, Angela Dell’Aversano, Antonio Cuccaro, Max Ammann, Rocco Pierri 2013 Seconda Università di Napoli

Detecting Point-Like Sources Of Unknown Frequency Spectra, Raffaele Solimene, Giuseppe Ruvio, Angela Dell’Aversano, Antonio Cuccaro, Max Ammann, Rocco Pierri

Articles

The problem of detecting point-like sources whose frequency spectrum is unknown is addressed. Limitations of single-frequency approaches are identified by analytical as well as numerical arguments. To overcome these limits, different multifrequency approaches which combine frequency data incoherently are compared. In particular, a novel multifrequency MUSIC-like algorithm based on interferometric concepts is proposed. Results show that the algorithm outperforms other methods under comparison.


Time Synchronization For Ofdm Transmission With Applications To 4g Wimax Wireless Systems, Hamad Alhajri 2013 Old Dominion University

Time Synchronization For Ofdm Transmission With Applications To 4g Wimax Wireless Systems, Hamad Alhajri

Electrical & Computer Engineering Theses & Dissertations

Orthogonal Frequency Division Multiplexing (OFDM) has recently gained a lot of attention as a promising new technology for Broadband Wireless Access. OFDM-based communication systems decompose a high rate data stream into a set of lower data rate streams that are transmitted simultaneously over multiple subcarriers. WiMAX is an efficient and reliable wireless transmission standard that employs OFDM transmission. Due to its flexibility and mobility, WiMAX is becoming a preferred air interface for next generation broadband wireless systems. OFDM systems, including WiMAX, are very sensitive to time offsets introduced by radio signal propagation between transmitters and receivers. The lack of time …


Stochastic Modeling And Time-To-Event Analysis Of Voip Traffic, Imad Al Ajarmeh 2013 DePaul University

Stochastic Modeling And Time-To-Event Analysis Of Voip Traffic, Imad Al Ajarmeh

College of Computing and Digital Media Dissertations

Voice over IP (VoIP) systems are gaining increased popularity due to the cost effectiveness, ease of management, and enhanced features and capabilities. Both enterprises and carriers are deploying VoIP systems to replace their TDM-based legacy voice networks. However, the lack of engineering models for VoIP systems has been realized by many researchers, especially for large-scale networks. The purpose of traffic engineering is to minimize call blocking probability and maximize resource utilization. The current traffic engineering models are inherited from the legacy PSTN world, and these models fall short from capturing the characteristics of new traffic patterns. The objective of this …


Automatic Modulation Classification Of Common Communication And Pulse Compression Radar Waveforms Using Cyclic Features, John A . Hadjis 2013 Air Force Institute of Technology

Automatic Modulation Classification Of Common Communication And Pulse Compression Radar Waveforms Using Cyclic Features, John A . Hadjis

Theses and Dissertations

This research develops a feature-based MAP classification system and applies it to classify several common pulse compression radar and communication modulations. All signal parameters are treated as unknown to the classifier system except SNR and the signal carrier frequency. The features are derived from estimated duty cycle, cyclic spectral correlation, and cyclic cumulants. The modulations considered in this research are BPSK, QPSK, 16-QAM, 64-QAM, 8-PSK, and 16-PSK communication modulations, as well as Barker coded, Barker coded, Barker coded, Frank coded, Px49 coded, and LFM pulse compression modulations. Simulations show that average correct signal modulation type classification %C 90% is achieved …


Spectrum Regrowth For Ofdm-Based Lte And Wimax Systems, Bosi Chen 2013 Portland State University

Spectrum Regrowth For Ofdm-Based Lte And Wimax Systems, Bosi Chen

Dissertations and Theses

An abstract of the thesis of Bosi Chen for the Master of Science in Electrical and Computer Engineering presented Aug 1st, 2012. Title: Spectrum Regrowth for OFDM-based LTE and WiMAX Systems. In OFDM-based (Orthogonal Frequency Dimension Multiplexing) LTE (Long Term Evolution) and WiMAX (Worldwide Interoperability for Microwave Access) Systems, one of the critical components is the RF power amplifier. With current technologies, RF power amplifiers are not perfectly linear. The nonlinearity of an RF power amplifier is one of the main concerns in RF power amplifier design. The nonlinearity control is described by the out-of-band power emission levels, and the …


Comparison Of Post-Detonation Combustion In Explosives Incorporating Aluminum Nanoparticles: Influence Of The Passivation Layer, William K. Lewis, C. G. Rumchik, M. J. Smith, K. A. Shiral Fernando, Christopher A. Crouse, Jonathan E. Spowart, Elena A. Guliants, Christopher E. Bunker 2013 Air Force Research Laboratory

Comparison Of Post-Detonation Combustion In Explosives Incorporating Aluminum Nanoparticles: Influence Of The Passivation Layer, William K. Lewis, C. G. Rumchik, M. J. Smith, K. A. Shiral Fernando, Christopher A. Crouse, Jonathan E. Spowart, Elena A. Guliants, Christopher E. Bunker

Electrical and Computer Engineering Faculty Publications

Aluminum nanoparticles and explosive formulations that incorporate them have been a subject of ongoing interest due to the potential of aluminum particles to dramatically increase energy content relative to conventional organic explosives. We have used time-resolved atomic and molecular emission spectroscopy to monitor the combustion of aluminum nanoparticles within the overall chemical dynamicsof post-detonation fireballs. We have studied the energy release dynamics of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) charges incorporating three types of aluminum nanoparticles: commercial oxide-passivated nanoparticles, oleic acid-capped aluminum nanoparticles (AlOA), and nanoparticles in which the oxide shell of the particle has been functionalized with an acrylic monomer and copolymerized into …


Maintaining The Master International Frequency Register, Frans G. von der Dunk 2013 University of Nebraska - Lincoln

Maintaining The Master International Frequency Register, Frans G. Von Der Dunk

Space, Cyber, and Telecommunications Law Program: Faculty Publications

The present paper is the written elaboration of a presentation held under the same title at the workshop “International Regulations of Space Communications” held in Luxembourg on 24 and 25 May 2012. Consequently, the topic of this paper, the maintenance of the Master International Frequency Register as a key tool for allowing satellite communications to be a viable international sector of space activities, is viewed through the looking glass of the session title, “WRC-12 from the Perspective of International Telecommunications Law.”

In other words, it does not purport to deal with the actual details of maintaining the Register …


A New Variable Step-Size Zero-Point Attracting Projection Algorithm, Jianming Liu, Steven L. Grant 2013 Missouri University of Science and Technology

A New Variable Step-Size Zero-Point Attracting Projection Algorithm, Jianming Liu, Steven L. Grant

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a new variable step-size (VSS) scheme for the recently introduced zero-point attracting projection (ZAP) algorithm. The proposed variable step-size ZAPs are based on the gradient of the estimated filter coefficients' sparseness that is approximated by the difference between the sparseness measure of current filter coefficients and an averaged sparseness measure. Simulation results demonstrate that the proposed approach provides both faster convergence rate and better tracking ability than previous ones. © 2013 IEEE.


Independent Component Analysis Enhancements For Source Separation In Immersive Audio Environments, Yue Zhao 2013 University of Kentucky

Independent Component Analysis Enhancements For Source Separation In Immersive Audio Environments, Yue Zhao

Theses and Dissertations--Electrical and Computer Engineering

In immersive audio environments with distributed microphones, Independent Component Analysis (ICA) can be applied to uncover signals from a mixture of other signals and noise, such as in a cocktail party recording. ICA algorithms have been developed for instantaneous source mixtures and convolutional source mixtures. While ICA for instantaneous mixtures works when no delays exist between the signals in each mixture, distributed microphone recordings typically result various delays of the signals over the recorded channels. The convolutive ICA algorithm should account for delays; however, it requires many parameters to be set and often has stability issues. This thesis introduces the …


Dual-Band Omnidirectional Circularly Polarized Antenna, Adam Narbudowicz, Xiulong Bao, Max Ammann 2013 Technological University Dublin

Dual-Band Omnidirectional Circularly Polarized Antenna, Adam Narbudowicz, Xiulong Bao, Max Ammann

Articles

A dual-band omnidirectional circularly polarized antenna is proposed. The antenna comprises back-to-back microstrip patches fed by a coplanar waveguide. A very low frequency ratio of 1.182 has been achieved, which can be easily tuned by adjusting four lumped capacitors incorporated into the antenna. An analysis of the omnidirectional circular polarization mechanism as well the dual band operation is provided and confirmed by numerical and experimental data. Key parameters to tune the resonant frequencies and the axial ratio have been identified. The prototype antenna provides omnidirectional circular polarization in one plane with cross polar isolation better than 12 dB for both …


Tunable Fano Resonances Based On Two-Beam Interference In Microring Resonator, Ting Hu, Ping Yu, Chen Qui, Huiye Qui, Fan Wang, Mei Yang, Xiaoqing Jiang, Hui Yu, Jianyi Yang 2013 Zhejiang University of Technology

Tunable Fano Resonances Based On Two-Beam Interference In Microring Resonator, Ting Hu, Ping Yu, Chen Qui, Huiye Qui, Fan Wang, Mei Yang, Xiaoqing Jiang, Hui Yu, Jianyi Yang

Electrical & Computer Engineering Faculty Research

In this paper, a resonant system is demonstrated on silicon-on-insulator wafer to achieve tunable Fano resonances. In this system, the Fano resonance originates from the interference of two beams resonant in the microring resonator. The shapes of the Fano resonances are tunable through controlling the phase difference of the two beams. Both large slope and high extinctionratio (ER) are obtained when the phase difference is 0.5π or 1.5π. Experimental results show that Fano resonances with steep slope and ER over 20 dB are achieved in the whole free spectral range by controlling the microheaters to meet the phase condition.


Estimation Of Performance Indices For The Planning Of Sustainable Transportation Systems, Alexander Paz, Pankaj Maheshwari 2013 University of Nevada, Las Vegas

Estimation Of Performance Indices For The Planning Of Sustainable Transportation Systems, Alexander Paz, Pankaj Maheshwari

Electrical & Computer Engineering Faculty Research

In the context of sustainable transportation systems, previous studies have either focused only on the transportation systemor have not used a methodology that enables the treatment of incomplete, vague, and qualitative information associated with the available data. This study proposes a system of systems (SOS) and a fuzzy logic modeling approach. The SOS includes the Transportation, Activity, and Environment systems. The fuzzy logic modeling approach enables the treatment of the vagueness associated with some of the relevant data. Performance Indices (PIs) are computed for each system using a number of performance measures. The PIs illustrate the aggregated performance of each …


Optimal Network Topologies And Resource Mappings For Heterogeneous Networks-On-Chip, Haera Chung 2013 Portland State University

Optimal Network Topologies And Resource Mappings For Heterogeneous Networks-On-Chip, Haera Chung

Dissertations and Theses

Communication has become a bottleneck for modern microprocessors and multi-core chips because metal wires don't scale. The problem becomes worse as the number of components increases and chips become bigger. Traditional Systems-on-Chips (SoCs) interconnect architectures are based on shared-bus communication, which can carry only one communication transaction at a time. This limits the communication bandwidth and scalability. Networks-on-Chip (NoC) were proposed as a promising solution for designing large and complex SoCs. The NoC paradigm provides better scalability and reusability for future SoCs, however, long-distance multi-hop communication through traditional metal wires suffers from both high latency and power consumption. A radical …


Performance Evaluation And Comparison Of Distributed Messaging Using Message Oriented Middleware, Naveen Mupparaju 2013 University of North Florida

Performance Evaluation And Comparison Of Distributed Messaging Using Message Oriented Middleware, Naveen Mupparaju

UNF Graduate Theses and Dissertations

Message Oriented Middleware (MOM) is an enabling technology for modern event- driven applications that are typically based on publish/subscribe communication [Eugster03]. Enterprises typically contain hundreds of applications operating in environments with diverse databases and operating systems. Integration of these applications is required to coordinate the business process. Unfortunately, this is no easy task. Enterprise Integration, according to Brosey et al. (2001), "aims to connect and combines people, processes, systems, and technologies to ensure that the right people and the right processes have the right information and the right resources at the right time"[Brosey01]. Communication between different applications can be achieved …


Bit Error Rate Estimation In Wimax Communications At Vehicular Speeds Using Nakagami-M Fading Model, Biswojit Bose 2013 Edith Cowan University

Bit Error Rate Estimation In Wimax Communications At Vehicular Speeds Using Nakagami-M Fading Model, Biswojit Bose

Theses: Doctorates and Masters

The wireless communication industry has experienced a rapid technological evolution from its basic first generation (1G) wireless systems to the latest fourth generation (4G) wireless broadband systems. Wireless broadband systems are becoming increasingly popular with consumers and the technological strength of 4G has played a major role behind the success of wireless broadband systems. The IEEE 802.16m standard of the Worldwide Interoperability for Microwave Access (WiMAX) has been accepted as a 4G standard by the Institute of Electrical and Electronics Engineers in 2011. The IEEE 802.16m is fully optimised for wireless communications in fixed environments and can deliver very high …


Conductive Concrete For Electromagnetic Shielding – Methods For Development And Evaluation, Aaron P. Krause 2012 University of Nebraska-Lincoln

Conductive Concrete For Electromagnetic Shielding – Methods For Development And Evaluation, Aaron P. Krause

Department of Computer Electronics and Engineering: Dissertations, Theses, and Student Research

This research investigates the development and evaluation innovative methods for the use of conductive concrete as an electromagnetic shield. New testing methods are developed to determine the best conductive components to use in the design of a concrete mixture for shielding that shows the best promise. The conductive concrete mixture has the potential to provide electromagnetic shielding that is cost-effective in terms of construction, operation, and maintenance compared to conventional approaches. Two testing methods, Small Sample Testing and Large Slab Testing, are developed based on standardized testing methods that have been modified for the testing of conductive concrete mixtures. As …


Radio Link Analysis And Characterization Of Past And Future Cal Poly Cubesats, Brian Gilbert Tubb 2012 California Polytechnic State University - San Luis Obispo

Radio Link Analysis And Characterization Of Past And Future Cal Poly Cubesats, Brian Gilbert Tubb

Electrical Engineering

Cal Poly's satellites design team, PolySat, has three satellites in Low Earth Orbit (LEO) and four more planned to launch within the next two years. Radio communication of past and current orbiting satellites has been an exercise in frustration, prompting significant research into the satellite-side of the radio link by several other Senior Projects and Thesis papers. However, minimal effort has been spent on evaluating why these problems were discovered only once the satellites reached orbit. This paper details the downfalls of relying heavily on link budgets and improper long range test setups, then experimentally determines the sensitivity of PolySat's …


Radio Direction Finding Network Receiver Design For Low-Cost Public Service Applications, Marcel Colman Eric Stieber 2012 California Polytechnic State University, San Luis Obispo

Radio Direction Finding Network Receiver Design For Low-Cost Public Service Applications, Marcel Colman Eric Stieber

Master's Theses

A low-cost radio direction finding (RDF) VHF receiver has been investigated for development into a radio direction finding network (RDFN) with a particular focus towards public service and commercial asset tracking applications. The primary design criteria were reproducibility, low-cost, and simplicity such that public service and volunteer organizations can benefit from the technology. Two receiver designs were built and tested to allow for comparison of practicality, cost, and accuracy. A pseudo-Doppler RDF and a time difference of arrival (TDOA) receiver were built as proof-of-concept for a system design based on commercial off-the-shelf (COTS) components. The pseudo-Doppler system is a less …


Design And Analysis Of An Adaptive Asynchronous System Architecture For Energy Efficiency, Brent Michael Hollosi 2012 University of Arkansas, Fayetteville

Design And Analysis Of An Adaptive Asynchronous System Architecture For Energy Efficiency, Brent Michael Hollosi

Graduate Theses and Dissertations

Power has become a critical design parameter for digital CMOS integrated circuits. With performance still garnering much concern, a central idea has emerged: minimizing power consumption while maintaining performance. The use of dynamic voltage scaling (DVS) with parallelism has shown to be an effective way of saving power while maintaining performance. However, the potency of DVS and parallelism in traditional, clocked synchronous systems is limited because of the strict timing requirements such systems must comply with. Delay-insensitive (DI) asynchronous systems have the potential to benefit more from these techniques due to their flexible timing requirements and high modularity. This dissertation …


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