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Signal Processing Commons

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Articles 181 - 210 of 271

Full-Text Articles in Signal Processing

Prosense, Johnny Favazza Ii, Casey Glasgow, Matt Epperson Jun 2016

Prosense, Johnny Favazza Ii, Casey Glasgow, Matt Epperson

Computer Engineering

This project aims to gather advanced data sets from MEMS sensors and GPS and deliver it to the user, who can capitalize on the data. The once negligible half-degree difference of your board barreling down a wave can be recorded from a gyro and exploited for the perfect turn. The exact speed dreaded by longboarders where speed wobbles turn into a road rash can be analysed and consequently avoided. Ascertaining the summit of your flight using combined GPS sensors from the ski ramp allows for the correct timing of tricks. When it comes to pursuing excellence in professional sports, amateur …


Analysis Of Various Algorithmic Approaches To Software-Based 1200 Baud Audio Frequency Shift Keying Demodulation For Aprs, Robert F. Campbell Jun 2016

Analysis Of Various Algorithmic Approaches To Software-Based 1200 Baud Audio Frequency Shift Keying Demodulation For Aprs, Robert F. Campbell

Master's Theses

Digital communications continues to be a relevant Field of study as new technologies appear and old methodologies get revisited or renovated. The goal of this research is to look into the old digital communication scheme of Bell 202 [67] used by APRS and improve software based demodulation performance. Improved performance is defined by being able to correctly decode more packets in an efficient, real time, manner. Most APRS demodulation is currently done using specialized hardware since that yields the best performance. This research shows that through using Sivan Toledo's javAX25 [72] software package, new demodulation algorithms can be implemented that …


Source Separation Approach To Video Quality Prediction In Computer Networks, Ruairí De Fréin May 2016

Source Separation Approach To Video Quality Prediction In Computer Networks, Ruairí De Fréin

Articles

Time-varying loads introduce errors in the estimated model parameters of service-level predictors in Computer Networks. A load-adjusted modification of a traditional unadjusted service-level predictor is contributed, based on Source Separation (SS). It mitigates these errors and improves service-quality predictions for Video-on-Demand (VoD) by :6 to 2dB.


Design, Analysis, Implementation And Evaluation Of Real-Time Opportunistic Spectrum Access In Cloud-Based Cognitive Radio Networks, Nimish Sharma Jan 2016

Design, Analysis, Implementation And Evaluation Of Real-Time Opportunistic Spectrum Access In Cloud-Based Cognitive Radio Networks, Nimish Sharma

College of Graduate Studies: Theses & Dissertations

Opportunistic spectrum access in cognitive radio network is proposed for remediation of spectrum under-utilization caused by exclusive licensing for service providers that are intermittently utilizing spectrum at any given geolocation and time. The unlicensed secondary users (SUs) rely on opportunistic spectrum access to maximize spectrum utilization by sensing/identifying the idle bands without causing harmful interference to licensed primary users (PUs). In this thesis, Real-time Opportunistic Spectrum Access in Cloud-based Cognitive Radio Networks (ROAR) architecture is presented where cloud computing is used for processing and storage of idle channels. Software-defined radios (SDRs) are used as SUs and PUs that identify, report, …


Performance Analysis Of Secondary Users In Heterogeneous Cognitive Radio Network, Tanjil Amin Jan 2016

Performance Analysis Of Secondary Users In Heterogeneous Cognitive Radio Network, Tanjil Amin

College of Graduate Studies: Theses & Dissertations

Continuous increase in wireless subscriptions and static allocation of wireless frequency bands to the primary users (PUs) are fueling the radio frequency (RF) shortage problem. Cognitive radio network (CRN) is regarded as a solution to this problem as it utilizes the scarce RF in an opportunisticmanner to increase the spectrumefficiency. InCRN, secondary users (SUs) are allowed to access idle frequency bands opportunistically without causing harmful interference to the PUs. In CRN, the SUs determine the presence of PUs through spectrum sensing and access idle bands by means of dynamic spectrum access. Spectrum sensing techniques available in the literature do not …


Joint Detection-State Estimation And Secure Signal Processing, Mengqi Ren Jan 2016

Joint Detection-State Estimation And Secure Signal Processing, Mengqi Ren

Theses and Dissertations

In this dissertation, joint detection-state estimation and secure signal processing are studied. Detection and state estimation are two important research topics in surveillance systems. The detection problems investigated in this dissertation include object detection and fault detection. The goal of object detection is to determine the presence or absence of an object under measurement uncertainty. The aim of fault detection is to determine whether or not the measurements are provided by faulty sensors. State estimation is to estimate the states of moving objects from measurements with random measurement noise or disturbance, which typically consist of their positions and velocities over …


Design, Analysis And Evaluation Of Unmanned Aerial Vehicle Ad Hoc Network For Emergency Response Communications, Robin D. Grodi Jan 2016

Design, Analysis And Evaluation Of Unmanned Aerial Vehicle Ad Hoc Network For Emergency Response Communications, Robin D. Grodi

College of Graduate Studies: Theses & Dissertations

In any emergency situation, it is paramount that communication be established between those affected by an emergency and the emergency responders. This communication is typically initiated by contacting an emergency service number such as 9-1-1 which will then notify the appropriate responders. The communication link relies heavily on the use of the public telephone network. If an emergency situation causes damage to, or otherwise interrupts, the public telephone network then those affected by the emergency are unable to call for help or warn others. A backup emergency response communication system is required to restore communication in areas where the public …


Real-Time Digital Effects Processing Using Ios, Jonah W. Clinard Dec 2015

Real-Time Digital Effects Processing Using Ios, Jonah W. Clinard

Computer Engineering

In today’s society, we are seeing incredible improvements in terms of creating smaller technological devices that behave more and more like the personal computers of yesterday. Mobile “Smart” devices, in particular, are becoming incredibly powerful not just in terms of processing power, but in the fact that they are able to provide assistance to users in their everyday lives. Application developers are now able utilize the power and size of these devices, to create and realize ideas that would have been previously viewed as impossible. This project applies the fields of digital signal processing, music, and mobile application development, to …


Scaled Synthetic Aperture Radar System Development, Ryan K. Green Dec 2015

Scaled Synthetic Aperture Radar System Development, Ryan K. Green

Master's Theses

Synthetic Aperture Radar (SAR) systems generate two dimensional images of a target area using RF energy as opposed to light waves used by cameras. When cloud cover or other optical obstructions prevent camera imaging over a target area, SAR can be substituted to generate high resolution images. Linear frequency modulated signals are transmitted and received while a moving imaging platform traverses a target area to develop high resolution images through modern digital signal processing (DSP) techniques. The motivation for this joint thesis project is to design and construct a scaled SAR system to support Cal Poly radar projects. Objectives include …


Protecting Fly-By-Wireless Systems From Remote Attacks, Vahid Heydari Oct 2015

Protecting Fly-By-Wireless Systems From Remote Attacks, Vahid Heydari

Von Braun Symposium Student Posters

No abstract provided.


Classification Of Digital Communication Signal Modulation Schemes In Multipath Environments Using Higher Order Statistics, Meena Sreekantamurthy Jul 2015

Classification Of Digital Communication Signal Modulation Schemes In Multipath Environments Using Higher Order Statistics, Meena Sreekantamurthy

Electrical & Computer Engineering Theses & Dissertations

Automatic identification and classification of modulation schemes in communication signals and decoding of information from the captured signals has assumed great importance recently in the wireless communication industry. Advancements in communications have introduced a large variety of modulation schemes in the transmitted signals; consequently, reliable detection of the modulation scheme in the intercepted signal has become an important issue in communications. It is the aim of this thesis to address this issue of reliable detection. Therefore, this research is focused on modeling and simulation of an automatic modulation classifier and, in particular, on the development of algorithms to use higher …


Unmanned Aircraft Systems: Air-Ground Channel Characterization For Future Applications, David W. Matolak, Ruoyu Sun Jun 2015

Unmanned Aircraft Systems: Air-Ground Channel Characterization For Future Applications, David W. Matolak, Ruoyu Sun

Faculty Publications

Unmanned aircraft systems (UASs) are being used increasingly worldwide. These systems will operate in conditions that differ from conventional piloted aircraft, and this implies that the airground (AG) channel for UASs can differ significantly from the traditional, simple, AG channel models. After providing some background and motivation, we describe the AG channel features and our efforts in measuring and modeling the AG channel. Some example measurement and model results-for the path loss and the Ricean K-factor-are provided to illustrate some of the interesting AG channel characteristics that are still being investigated.


Synthetic Aperture Radar: Rapid Detection Of Target Motion In Matlab, Daniel S. Kassen May 2015

Synthetic Aperture Radar: Rapid Detection Of Target Motion In Matlab, Daniel S. Kassen

Master's Theses

Synthetic Aperture Radar (SAR) has come into widespread use in several civilian and military applications. The focus of this paper is the military application of imaging point targets captured by an airborne SAR platform. Using the traditional SAR method of determining target motion by analyzing the difference between subsequent images takes a relatively large amount of processing resources. Using methods in this thesis, target motion can be estimated before even a single image is obtained, reducing the amount of time and power used by a significantly large amount. This thesis builds on work done by Brain Zaharri and David So. …


Energy Harvesting And Storage: The Catalyst To The Power Constraint For Leveraging Internet Of Things (Iot) On Trains, Kelechi Nwogu May 2015

Energy Harvesting And Storage: The Catalyst To The Power Constraint For Leveraging Internet Of Things (Iot) On Trains, Kelechi Nwogu

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

The success of Wireless Sensor Networks is heavily constrained by its reliance on storage technology like batteries, which are a finite resource. Whilst the number of transistors in an IC doubles every 18 months, the energy density of batteries is relatively flat during the same time period. This is a key challenge in leveraging the Internet of Things on trains.

The gravity of this problem is increased by an order of magnitude when the network is to be scaled up to hundreds or thousands of nodes. Comprehensive research and development efforts have been devoted to building ultra-low power sensors. These …


Simple Secrecy: Analog Stream Cipher For Secure Voice Communication, John M. Campbell Apr 2015

Simple Secrecy: Analog Stream Cipher For Secure Voice Communication, John M. Campbell

Senior Honors Theses

Voice signals are inherently analog, and some voice communication systems still utilize analog signals. Existing analog cryptographic methods do not satisfactorily provide cryptosecurity for communication systems due to several limitations. This paper proposes a novel means of provided cryptosecurity for analog signals without digitization; thereby avoiding the latency which results from ADC/DAC conversions. This method utilizes the principles of the digital stream cipher, generating instead a continuous pseudorandom analog key stream signal which is transformed with the original analog signal to create an encrypted ciphertext signal which is statistically independent of the original signal and the key stream signal. The …


Hybrid Single And Dual Pattern Structured Light Illumination, Minghao Wang Jan 2015

Hybrid Single And Dual Pattern Structured Light Illumination, Minghao Wang

Theses and Dissertations--Electrical and Computer Engineering

Structured Light Illumination is a widely used 3D shape measurement technique in non-contact surface scanning. Multi-pattern based Structured Light Illumination methods reconstruct 3-D surface with high accuracy, but are sensitive to object motion during the pattern projection and the speed of scanning process is relatively long. To reduce this sensitivity, single pattern techniques are developed to achieve a high speed scanning process, such as Composite Pattern (CP) and Modified Composite Pattern (MCP) technique. However, most of single patter techniques have a significant banding artifact and sacrifice the accuracy. We focus on developing SLI techniques can achieve both high speed, high …


Design And Software Validation Of Coded Communication Schemes Using Multidimensional Signal Sets Without Constellation Expansion Penalty In Band-Limited Gaussian And Fading Channels, Milton I. Quinteros Dec 2014

Design And Software Validation Of Coded Communication Schemes Using Multidimensional Signal Sets Without Constellation Expansion Penalty In Band-Limited Gaussian And Fading Channels, Milton I. Quinteros

LSU New Orleans Theses and Dissertations

It has been well reported that the use of multidimensional constellation signals can help to reduce the bit error rate in Additive Gaussian channels by using the hyperspace geometry more efficiently. Similarly, in fading channels, dimensionality provides an inherent signal space diversity (distinct components between two constellations points), so the amplitude degradation of the signal are combated significantly better.

Moreover, the set of n-dimensional signals also provides great compatibility with various Trellis Coded modulation schemes: N-dimensional signaling joined with a convolutional encoder uses fewer redundant bits for each 2D signaling interval, and increases intra-subset minimum squared Euclidean distance (MSED) to …


Comparison Of Nonlinear Filtering Methods For Battery State Of Charge Estimation, Klaus Zhang Aug 2014

Comparison Of Nonlinear Filtering Methods For Battery State Of Charge Estimation, Klaus Zhang

LSU New Orleans Theses and Dissertations

In battery management systems, the main figure of merit is the battery's SOC, typically obtained from voltage and current measurements. Present estimation methods use simplified battery models that do not fully capture the electrical characteristics of the battery, which are useful for system design. This thesis studied SOC estimation for a lithium-ion battery using a nonlinear, electrical-circuit battery model that better describes the electrical characteristics of the battery. The extended Kalman filter, unscented Kalman filter, third-order and fifth-order cubature Kalman filter, and the statistically linearized filter were tested on their ability to estimate the SOC through numerical simulation. Their performances …


Data Chunking In Quasi-Synchronous Ds-Cdma, Trevor Dalke Jun 2014

Data Chunking In Quasi-Synchronous Ds-Cdma, Trevor Dalke

Master's Theses

DS-CDMA is a popular multiple access technique used in many mobile networks to efficiently share channel resources between users in a cell. Synchronization between users maximizes the user capacity of these systems. However, it is difficult to perfectly synchronize users in the reverse link due to the geographic diversity of mobile users in the cell. As a result, most commercial DS-CDMA networks utilize an asynchronous reverse link resulting in a reduced user capacity. A possible compromise to increase the user capacity in the reverse link is to implement a quasi-synchronous timing scheme, a timing scheme in which users are allowed …


Studies In Software-Defined Radio System Implementation, Harold A. Haldren Iii Apr 2014

Studies In Software-Defined Radio System Implementation, Harold A. Haldren Iii

Senior Honors Theses

Over the past decade, software-defined radios (SDRs) have an increasingly prevalent aspect of wireless communication systems. Different than traditional hardware radios which implement radio protocols using static electrical circuit, SDRs implement significant aspects of physical radio protocol using software programs running on a host processor. Because they use software to implement most of the radio functionality, SDRs are much more easily modified, edited, and upgraded than their hardware-defined counterparts. Consequently, researchers and developers have been developing previously hardware-defined radio systems within software. Thus, communication standards can be tested under different conditions or swapped out entirely by simply changing some code. …


Large-Scale Site And Frequency Diversity In Urban Peer-To-Peer Channels For Six Public Safety Frequency Bands, David W. Matolak, Kate A. Remley, Christopher L. Holloway, Qian Zhang, Qiong Wu Apr 2014

Large-Scale Site And Frequency Diversity In Urban Peer-To-Peer Channels For Six Public Safety Frequency Bands, David W. Matolak, Kate A. Remley, Christopher L. Holloway, Qian Zhang, Qiong Wu

Faculty Publications

We report on peer-to-peer large-scale wireless channel characteristics for an urban environment in six public-safety bands, for five simultaneous receiving sites. Results are based upon measurements taken in Denver in July 2009 with stationary receivers and a pedestrian transmitter. The six frequencies at which we measured are (in MHz) 430, 750, 905, 1834, 2400, and 4860. We quantify both site and frequency diversity, and show that 5-site selection yields minimum average gains of 15 dB in mean received power levels; 5-site selection diversity also reduces received power variation by 17-29 dB, depending on frequency. Frequency diversity yields similar gains. By …


Generator Polynomial Formulation For Parallel Counters With Applications, Lee A. Belfore Ii Jan 2014

Generator Polynomial Formulation For Parallel Counters With Applications, Lee A. Belfore Ii

Electrical & Computer Engineering Faculty Publications

Parallel counters have been studied for several decades as a component in high speed multipliers and multi-operand adder circuits. Using a generator polynomial as a formalism for describing parallel counters in the general case, parallel counter properties can be derived and inferred. Furthermore, the structure and decomposition of the generator polynomial can suggest different implementation strategies. These include simple implementations of (7,3) and (15,4) parallel counters. By grouping factors, the design of a fast (7,3) parallel counter is presented. Finally, the generator polynomial is extended to permit factors of different weights. This extension provides a means for describing the design …


A Study On Countermeasures Against Steganography: An Active Warden Approach, Qilin Qi Dec 2013

A Study On Countermeasures Against Steganography: An Active Warden Approach, Qilin Qi

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

Digital steganography is a method used for hiding information in digital images. It can be used for secure communication. There have been many robust digital steganography methods invented in recent decades. The steganographic message can be inserted in multimedia cover signal such as audio, image and video. However, this technique also may be used by malicious users to transmit dangerous information through the Internet beyond the control of security agencies. How to detect and/or block potentially dangerous information transmission on the Internet through billions of multimedia files while not affecting innocent multimedia communications becomes a challenging problem. Existing steganalysis methods …


Physiologically-Motivated Feature Extraction Methods For Speaker Recognition, Jianglin Wang Oct 2013

Physiologically-Motivated Feature Extraction Methods For Speaker Recognition, Jianglin Wang

Dissertations (1934 -)

Speaker recognition has received a great deal of attention from the speech community, and significant gains in robustness and accuracy have been obtained over the past decade. However, the features used for identification are still primarily representations of overall spectral characteristics, and thus the models are primarily phonetic in nature, differentiating speakers based on overall pronunciation patterns. This creates difficulties in terms of the amount of enrollment data and complexity of the models required to cover the phonetic space, especially in tasks such as identification where enrollment and testing data may not have similar phonetic coverage. This dissertation introduces new …


Understanding Vehicular Traffic Behavior From Video: A Survey Of Unsupervised Approaches, Brendan Tran Morris, Mohan Manubhai Trivedi Oct 2013

Understanding Vehicular Traffic Behavior From Video: A Survey Of Unsupervised Approaches, Brendan Tran Morris, Mohan Manubhai Trivedi

Electrical & Computer Engineering Faculty Research

Recent emerging trends for automatic behavior analysis and understanding from infrastructure video are reviewed. Research has shifted from high-resolution estimation of vehicle state and instead, pushed machine learning approaches to extract meaningful patterns in aggregates in an unsupervised fashion. These patterns represent priors on observable motion, which can be utilized to describe a scene, answer behavior questions such as where is a vehicle going, how many vehicles are performing the same action, and to detect an abnormal event. The review focuses on two main methods for scene description, trajectory clustering and topic modeling. Example applications that utilize the behavioral modeling …


Metrics For Emitter Selection For Multistatic Synthetic Aperture Radar, Sean R. Stevens Sep 2013

Metrics For Emitter Selection For Multistatic Synthetic Aperture Radar, Sean R. Stevens

Theses and Dissertations

A bistatic implementation of synthetic aperture radar (SAR) to form images of the ground from an aircraft makes use of separate emitters and receivers. When not using cooperative emitters, ground based communications systems can provide illumination. One way to improve performance of these waveforms, which are not designed for SAR, is a multistatic implementation, formed from multiple bistatic systems. This leads to the problem of selecting a subset from a potentially large set of emitters to use for image formation. A framework for this selection between sets of emitters is proposed using multiple objective optimization. This approach requires use of …


Adaptive Ofdm For Wireless Interconnect In Confined Enclosures, Vit Sipal, Javier Gelabert, Christopher J. Stevens, Ben Allen, David Edwards Jul 2013

Adaptive Ofdm For Wireless Interconnect In Confined Enclosures, Vit Sipal, Javier Gelabert, Christopher J. Stevens, Ben Allen, David Edwards

Articles

This letter considers and recommends OFDM with adaptive subcarrier modulation as a suitable candidate for wireless UWB communication in computer chassis. A rigorous measurement campaign studies the guaranteed spectral efficiency. It concludes that enhancement of the existing WiMedia OFDM systems with a bandwidth of 528 MHz in order to support adaptive OFDM would enable data-rates above 1 Gbps over short ranges, i.e. the spectral efficiency would be doubled. Moreover, the guaranteed spectral efficiency is shown to increase with bandwidth, i.e. the guaranteed data-rate increases better than linearly with bandwidth.


Path Loss In An Urban Peer-To-Peer Channel For Six Public-Safety Frequency Bands, David W. Matolak, Qian Zhang, Qiong Wu Jun 2013

Path Loss In An Urban Peer-To-Peer Channel For Six Public-Safety Frequency Bands, David W. Matolak, Qian Zhang, Qiong Wu

Faculty Publications

We provide path loss data and models for a peer-to-peer wireless channel for an urban environment in six public safety bands, for simultaneous transmission to five spatially separated receiving sites. Results are from measurements in Denver, Colorado. The six frequencies at which we measured are (in MHz) 430, 750, 905, 1834, 2400, and 4860. Both line-of-sight and non-line-of-sight conditions were covered, and we quantify path loss exponents and linear-fit standard deviations as functions of frequency and location. Line-of-sight results agree with prior work, but non-line-of-sight exponents, from 3.6-7.3, are generally larger than in most other references.


Impact Of Primary User Activity On The Performance Of Energy-Based Spectrum Sensing In Cognitive Radio Systems, Sara L. Macdonald Apr 2013

Impact Of Primary User Activity On The Performance Of Energy-Based Spectrum Sensing In Cognitive Radio Systems, Sara L. Macdonald

Electrical & Computer Engineering Theses & Dissertations

Increasing numbers of wireless devices and mobile data requirements have led to a spectrum shortage. However spectrum utilization percentages are often low due to the current static spectrum allocation process where primary users (PUs) are given exclusive use to spectrum. Several mechanisms to increase spectrum utilization have been proposed including opportunistic spectrum access (OSA). Cognitive Radio (CR) is an emerging concept in wireless communication systems that aims to enable OSA in licensed frequencies by secondary users (SUs). CR systems are expected to sense the spectrum in order to determine if the PU is transmitting. Therefore OSA performance relies on the …


Automatic Modulation Classification Of Common Communication And Pulse Compression Radar Waveforms Using Cyclic Features, John A . Hadjis Mar 2013

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 …