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Degrees Of Freedom Region For An Interference Network With General Message Demands, Lei Ke, Aditya Ramamoorthy, Zhengdao Wang, Huarui Yin 2017 Qualcomm, Inc.

Degrees Of Freedom Region For An Interference Network With General Message Demands, Lei Ke, Aditya Ramamoorthy, Zhengdao Wang, Huarui Yin

Zhengdao Wang

We consider a single hop interference network with K transmitters, each with an independent message and J receivers, all having the same number (M) of antennas. Each receiver requests an arbitrary subset of the messages. This generalizes the well-known K user M antenna interference channel, where each message is requested by a unique receiver. For this setup, we derive the exact degrees of freedom (DoF) region. Our achievability scheme generalizes the interference alignment scheme proposed by Cadambe and Jafar '08. In particular, we achieve general points in the DoF region by using multiple base vectors and aligning the interference at ...


Differential Tilt Variance Effects Of Turbulence In Imagery: Comparing Simulation With Theory, Daniel A. LeMaster, Russell C. Hardie, Szymon Gladysz, Matthew D. Howard, Michael Armand Rucci, Matthew E. Trippel, Jonathan D. Power, Barry K. Karch 2017 Air Force Research Laboratory

Differential Tilt Variance Effects Of Turbulence In Imagery: Comparing Simulation With Theory, Daniel A. Lemaster, Russell C. Hardie, Szymon Gladysz, Matthew D. Howard, Michael Armand Rucci, Matthew E. Trippel, Jonathan D. Power, Barry K. Karch

Russell C. Hardie

Differential tilt variance is a useful metric for interpreting the distorting effects of turbulence in incoherent imaging systems. In this paper, we compare the theoretical model of differential tilt variance to simulations. Simulation is based on a Monte Carlo wave optics approach with split step propagation. Results show that the simulation closely matches theory. The results also show that care must be taken when selecting a method to estimate tilts.


Efficient Macromodeling And Fast Transient Simulation Of High Speed Distributed Interconnects, Sadia Wahid 2017 The University of Western Ontario

Efficient Macromodeling And Fast Transient Simulation Of High Speed Distributed Interconnects, Sadia Wahid

Electronic Thesis and Dissertation Repository

In the first part of the thesis, an efficient macromodeling technique based on Loewner Matrix (LM) approach has been presented to model multi-port distributed systems using tabulated noisy data. In the proposed method, Loewner Model data from previous rational approximation are used to create less noisy eigenvectors in an iterative manner. As a result, the biasing effect of the LM model approximated by the noisy data is reduced. It is illustrated that this method improves the accuracy of the Loewner Matrix modeling for noisy frequency data.

In the second part, a fast and robust algorithm is introduced for time-domain simulation ...


Recursive Robust Pca Or Recursive Sparse Recovery In Large But Structured Noise, Chenlu Qiu, Namrata Vaswani, Brian Lois, Leslie Hogben 2017 Iowa State University

Recursive Robust Pca Or Recursive Sparse Recovery In Large But Structured Noise, Chenlu Qiu, Namrata Vaswani, Brian Lois, Leslie Hogben

Namrata Vaswani

This paper studies the recursive robust principal components analysis problem. If the outlier is the signal-of-interest, this problem can be interpreted as one of recursively recovering a time sequence of sparse vectors, St, in the presence of large but structured noise, Lt. The structure that we assume on Lt is that Lt is dense and lies in a low-dimensional subspace that is either fixed or changes slowly enough. A key application where this problem occurs is in video surveillance where the goal is to separate a slowly changing background (Lt) from moving foreground objects (St) on-the-fly. To solve the above ...


Capturing Cognitive Fingerprints From Keystroke Dynamics, J. Morris Chang, Chi-Chen Fang, Kuan-Hsing Ho, Norene Kelly, Pei-Yuan Wu, Yixiao Ding, Chris Chu, Stephen B. Gilbert, Amed E. Kamal, Sun-Yuan Kung 2017 Iowa State University

Capturing Cognitive Fingerprints From Keystroke Dynamics, J. Morris Chang, Chi-Chen Fang, Kuan-Hsing Ho, Norene Kelly, Pei-Yuan Wu, Yixiao Ding, Chris Chu, Stephen B. Gilbert, Amed E. Kamal, Sun-Yuan Kung

Morris Chang

Conventional authentication systems identify a user only at the entry point. Keystroke dynamics can continuously authenticate users by their typing rhythms without extra devices. This article presents a new feature called cognitive typing rhythm (CTR) to continuously verify the identities of computer users. Two machine techniques, SVM and KRR, have been developed for the system. The best results from experiments conducted with 1,977 users show a false-rejection rate of 0.7 percent and a false-acceptance rate of 5.5 percent. CTR therefore constitutes a cognitive fingerprint for continuous. Its effectiveness has been verified through a large-scale dataset. This article ...


Impact Of Threshold Clipping On Bit Error Rate In Ofdm-Like Systems, Felipe Hoshino, Theodore Grosch 2017 University of Campinas

Impact Of Threshold Clipping On Bit Error Rate In Ofdm-Like Systems, Felipe Hoshino, Theodore Grosch

The Kennesaw Journal of Undergraduate Research

In wireless communications, 3GPP LTE is one of the solutions to meet the greater transmission data rate demand. One issue inherent to this technology is the PAPR (Peak-to-Average Power Ratio) of OFDM (Orthogonal Frequency Division Multiplexing) modulation. This high PAPR affects of the efficiency of power amplifiers. One approach to mitigate this effect is the Crest Factor Reduction (CFR) technique. In this work we simulate the impact of Hard Limited Clipping Crest Factor Reduction technique on BER (Bit Error Rate) in OFDM based Systems. In general, the results showed CFR has more effect on higher digital modulation schemes, as expected ...


Autonomous Speed Control For Kia Optima, Andrew J. Combs, Kyle Fugatt, Kevin McFall 2017 Kennesaw State University

Autonomous Speed Control For Kia Optima, Andrew J. Combs, Kyle Fugatt, Kevin Mcfall

The Kennesaw Journal of Undergraduate Research

The standard method for speed control is the cruise control system built into most modern vehicles. These systems employ a PID controller which actuates the accelerator thus, in turn, maintains the desired vehicle speed. The main drawback of such a system is that typically the cruise control will only engage above 25 mph. The goal of this paper is to describe a system which we used to control vehicle speed from a stop to any desired speed using an Arduino microcontroller and a CAN BUS shield, from where autonomous features can be built upon. With this system, we were able ...


Network Connection Blocker, Method, And Computer Readable Memory For Monitoring Connections In A Computer Network And Blocking The Unwanted Connections, Douglas W. Jacobson, James A. Davis 2017 Iowa State University

Network Connection Blocker, Method, And Computer Readable Memory For Monitoring Connections In A Computer Network And Blocking The Unwanted Connections, Douglas W. Jacobson, James A. Davis

Douglas Jacobson

A network connection blocker for monitoring connections between host computers in a network and blocking the unwanted connections. The host computers transmit connection packets between each other in accordance with a network protocol suite when seeking to establish, providing network services with, and close the connections. The network protocol suite includes a connection oriented transport layer protocol. The network connection blocker comprises a network interface that receives the connection packets transmitted between the host computers. It also comprises a blocking module that processes the received connection packets to detect the unwanted connections. The blocking module then generates connection packets in ...


Smart Grid Technology In The Developing World, Jacob R. Young 2017 Seattle Pacific University

Smart Grid Technology In The Developing World, Jacob R. Young

Honors Projects

A smart grid is the integration of communication and information technologies with contemporary power infrastructure to enhance load service and to incorporate continually evolving end-use applications. It is the latest advancement in the areas of power generation, transmission and distribution. It has advanced beyond the traditional grid structure at every stage; a smart grid is capable of incorporating distributed generation (DG) renewable sources and has improved transmission capabilities through implementation of technologies such as Flexible AC Transmission Systems (FACTS). Through the addition of control technology in the distribution network a smart grid is able to implement “self-healing” and other methods ...


The Following Robot, Juan D. Cerda, Matthew S. Kwan, Vi M. Le 2017 California Polytechnic State University, San Luis Obispo

The Following Robot, Juan D. Cerda, Matthew S. Kwan, Vi M. Le

Computer Engineering

The objective of this project is to design, build, and test an autonomous robot with an associated Android application. The robot uses on board inertial measurement sensors (magnetometer, accelerometer, gyroscope) and coordinates itself through Bluetooth communication with the similar built­in measurement sensors on the Android phone to mimic and follow movement. The Following Robot incorporates the same basic movement functionality as a typical RC car. The robot follows the user’s phone through an application on one’s phone. This application accesses the phone’s accelerometer and gyroscope data and translates into appropriate conversions. Methods of tracking and calculating ...


Remote Cable Gantry, Allen L. Bailey 2017 California Polytechnic State University, San Luis Obispo

Remote Cable Gantry, Allen L. Bailey

Electrical Engineering

The Remote Cable Gantry is a robotic system that was initially intended to aid in the art of aerial videography. It was designed to enable novice and expert users alike to capture both video footage and audio from perspectives unachievable by current methods. This system uses a series of cables to control the position of a camera gimbal in a defined 3D space and, as a self-contained unit, is portable and easy to use. The Remote Cable Gantry offers a quiet, intuitive, and safe alternative to existing technology, which has been limiting the market and potential of aerial photography and ...


Wireless Communication For Greenhouse Environment, Chris J. Lambert, Dean T. Lockman, Ian A. Nielsen 2017 California Polytechnic State University, San Luis Obispo

Wireless Communication For Greenhouse Environment, Chris J. Lambert, Dean T. Lockman, Ian A. Nielsen

Electrical Engineering

Modern day population growth and global climate change requires high-yield agricultural systems that can function in harsh environments. Greenhouses can maintain temperature and humidity, while serving as a protective, nurturing alternative to vulnerable farm environments. With weather effects eliminated, greenhouses provide productive environments for experimental agriculture techniques such as hydroponics and aquaculture. These methods of agriculture, specifically aquaculture, require constant monitoring. The failure of electronic devices such as an air pump prove fatal to a fish population in a short time frame. In developing countries, agricultural locations may be a significant distance from a farmer’s home, with no internet ...


Investigation Of Mimo Communications, Rodrigo Mendez Olea, William C. Tran, Patrick C. Kezer, Jean M. Whitmore 2017 California Polytechnic State University, San Luis Obispo

Investigation Of Mimo Communications, Rodrigo Mendez Olea, William C. Tran, Patrick C. Kezer, Jean M. Whitmore

Electrical Engineering

This project focuses on the background of multiple input multiple output (MIMO) communication and its advantages over the other possible implementations. A background of wireless communication in regards to modulation types, information theory, antenna background and a hardware implementation using a VSA and VSG is provided. The theory is compared and verified with the hardware implementation with regards to the effect of the increase in the number of antennas and the parameter vector error magnitude.


Estimating Transit Ridership Patterns Through Automated Data Collection Technology: A Case Study In San Luis Obispo, California, Ashley Kim 2017 California Polytechnic State University – San Luis Obispo

Estimating Transit Ridership Patterns Through Automated Data Collection Technology: A Case Study In San Luis Obispo, California, Ashley Kim

Master's Theses and Project Reports

Public transportation offers a crucial solution to the travel demand in light of national and global economic, energy, and environmental challenges. If implemented effectively, public transit offers an affordable, convenient, and sustainable transportation mode. Implementation of new technologies for information-harvesting may lead to more effective transit operations. This study examines the potential of automated data collection technologies to analyzing and understand the origin-destination flow patterns, which is essential for transit route planning and stop location placement.

This thesis investigates the collection and analysis of data of passengers onboard San Luis Obispo Transit buses in February and March 2017 using Bluetooth ...


Complex Filters As Cascade Of Buffered Gingell Structures: Design From Band-Pass Constraints, Nicole M. Hay, Nicole M. Hay 2017 California Polytechnic State University, San Luis Obispo

Complex Filters As Cascade Of Buffered Gingell Structures: Design From Band-Pass Constraints, Nicole M. Hay, Nicole M. Hay

Master's Theses and Project Reports

Complex filters are multi-input, multi-output networks designed to discriminate based upon the relative phase difference between input signals. Complex filters find application in modern wireless systems for single sideband transmission and image-reject reception. This thesis presents one active complex filter implementation using two operational amplifiers per stage, termed “type-II” topology. The “type-II” originates from the passive RC-CR polyphase topology presented by Gingell in his 1973 paper, “Single sideband modulation using sequence asymmetric polyphase networks.” This new topology gains several advantages over existing complex filter implementations, namely “cascadability” (multiple sections placed in series to create a higher-order response) without altering the ...


Verification Of Receiver Equalization By Integrating Dataflow Simulation And Physical Channels, David M. Ritter, Tina Smilkstein Dr. 2017 Cal Poly SLO State University

Verification Of Receiver Equalization By Integrating Dataflow Simulation And Physical Channels, David M. Ritter, Tina Smilkstein Dr.

Master's Theses and Project Reports

This thesis combines Keysight’s SystemVue software with a Vector Signal Analyzer (VSA) and Vector Signal Generator (VSG) to test receiver equalization schemes over physical channels. The testing setup, “Equalization Verification,” is intended to be able to evaluate any equalization scheme over any physical channel, and a decision-directed feed-forward LMS equalizer is used as an example. The decision-directed feed-forward LMS equalizer is shown to decrease the BER from 10-2 to 10-3 (average of all trials) over a CAT7 and CAT6A cable, both simulated and physical, for 1GHz and 2GHz carrier, and 80MHz data rate. A wireless channel, 2 ...


Detecting Insider Threats Using Radish: A System For Real-Time Anomaly Detection In Heterogeneous Data Streams, Northrop Grumman Corporation, Srikanta Tirthapura, Yung-Yu Chung 2017 Iowa State University

Detecting Insider Threats Using Radish: A System For Real-Time Anomaly Detection In Heterogeneous Data Streams, Northrop Grumman Corporation, Srikanta Tirthapura, Yung-Yu Chung

Electrical and Computer Engineering Publications

We present a scalable system for high-throughput real-time analysis of heterogeneous data streams. Our architecture enables incremental development of models for predictive analytics and anomaly detection as data arrives into the system. In contrast with batch data-processing systems, such as Hadoop, that can have high latency, our architecture allows for ingest and analysis of data on the fly, thereby detecting and responding to anomalous behavior in near real time. This timeliness is important for applications such as insider threat, financial fraud, and network intrusions. We demonstrate an application of this system to the problem of detecting insider threats, namely, the ...


Vehicle Occupancy Detection System, Hannah Miller, Justin Wert, Kelsey Lunberg 2017 University of Wyoming

Vehicle Occupancy Detection System, Hannah Miller, Justin Wert, Kelsey Lunberg

Honors Theses AY 16/17

Personal vehicles often become traps for unattended occupants throughout the year. Sadly, this can lead to severe health complications or even death if exposed for too long. Although these complications arise primarily in hot climates, it has been demonstrated that they can happen in any environment. Prolonged exposure to an unfamiliar and often dangerous setting without competent human intervention can be detrimental to health. This problem predominantly impacts pets and young children. In an effort to reduce these preventable health complications and possible deaths, we have developed a vehicle occupancy detection system.

The goal of developing this occupancy detection system ...


Dynamic Shadow-Power Estimation For Wireless Communications, Aleksandar Dogandžić, Benhong Zhang 2017 Iowa State University

Dynamic Shadow-Power Estimation For Wireless Communications, Aleksandar Dogandžić, Benhong Zhang

Aleksandar Dogandžić

We present a sequential Bayesian method for dynamic estimation and prediction of local mean (shadow) powers from instantaneous signal powers in composite fading-shadowing wireless communication channels. We adopt a Nakagami-m fading model for the instantaneous signal powers and a first-order autoregressive [AR(1)] model for the shadow process in decibels. The proposed dynamic method approximates predictive shadow-power densities using a Gaussian distribution. We also derive Crame/spl acute/r-Rao bounds (CRBs) for stationary lognormal shadow powers and develop methods for estimating the AR model parameters. Numerical simulations demonstrate the performance of the proposed methods.


Bayesian Nde Defect Signal Analysis, Aleksandar Dogandžić, Benhong Zhang 2017 Iowa State University

Bayesian Nde Defect Signal Analysis, Aleksandar Dogandžić, Benhong Zhang

Aleksandar Dogandžić

We develop a hierarchical Bayesian approach for estimating defect signals from noisy measurements and apply it to nondestructive evaluation (NDE) of materials. We propose a parametric model for the shape of the defect region and assume that the defect signals within this region are random with unknown mean and variance. Markov chain Monte Carlo (MCMC) algorithms are derived for simulating from the posterior distributions of the model parameters and defect signals. These algorithms are then utilized to identify potential defect regions and estimate their size and reflectivity parameters. Our approach provides Bayesian confidence regions (credible sets) for the estimated parameters ...


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