Engineering Commons^™

Gps-Denied Navigation Using Synthetic Aperture Radar, Tucker Hathaway

All Graduate Theses and Dissertations, Fall 2023 to Present

In most modern navigation systems, GPS is used to determine the precise location of the vehicle; however, GPS signals can easily be blocked, jammed, or spoofed. These signals can be blocked by canyons or tall buildings. Additionally, adversaries can transmit signals that either make GPS signals difficult to interpret or that imitate real GPS signals and cause a navigation system to think it is somewhere other than its true location. GPS-denied (GPS-D) navigation is the process of navigating in the absence of GPS.

Many methods of performing GPS-D navigation have been proposed and explored. One such method is to use …

High-Isolation Antenna Technique For Cubesat-Borne, Continuous-Waveform Radar, Logan E. Voigt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Radar is important in target tracking, imaging, and weather prediction applications. As technology is increasingly miniaturized, there is a push for smaller radar. Research and exploration in outer space also benefit from small, low-power technologies. The NASA Jet Propulsion Laboratory’s RainCube was the first successful CubeSat-borne radar. A CubeSat is a type of small satellite that conforms to specific size and weight standards. Radar technology benefits from additional research on how to further miniaturize radar payloads.

Integrating the transmit and receive antennas on the solar panels removes the need for antenna-deployment mechanisms, preserving space on the CubeSat. This thesis also …

Recognizing Traffic Signaling Gestures Through Automotive Sensors., Benjamin James Bartlett

Theses and Dissertations

As technology advances with each new day, so do the applications and uses of the different modalities of technology, including transportation, particularly in ADAS vehicles. These systems allow the vehicle to avoid collisions, change lanes, adjust the vehicle’s speed, and more without the need of driver input. However, each sensor type has a weakness, and most advanced driver- assisted system (ADAS) vehicles rely heavily on sensors, such as RGB cameras, radars, and LiDAR sensors. These visual-based sensors may collect very noisy data in cloudy, raining, foggy, or other obscuring phenomena. Radar, on the other hand, does not rely on visual …

Covert Communications In Continuous-Time Systems, Ke Li

Doctoral Dissertations

This dissertation studies covert wireless communications where a transmitter (Alice) intends to transmit messages to a legitimate receiver (Bob) such that the presence of the message is hidden from an attentive warden (Willie). Here we consider pertinent aspects of covert communications that focus on moving such systems closer to implementation. For example, previous studies use the standard discrete-time communication model when analyzing covert communications, since this is commonly assumed without loss of generality in standard communication theory. However, it is not clear that such a model captures the salient aspects of the continuous-time covert communications problem. A power detector that …

Non-Contact Techniques For Human Vital Sign Detection And Gait Analysis, Farnaz Foroughian

Doctoral Dissertations

Human vital signs including respiratory rate, heart rate, oxygen saturation, blood pressure, and body temperature are important physiological parameters that are used to track and monitor human health condition. Another important biological parameter of human health is human gait. Human vital sign detection and gait investigations have been attracted many scientists and practitioners in various fields such as sport medicine, geriatric medicine, bio-mechanic and bio-medical engineering and has many biological and medical applications such as diagnosis of health issues and abnormalities, elderly care and health monitoring, athlete performance analysis, and treatment of joint problems. Thoroughly tracking and understanding the normal …

Chaos-Based Coffee Can Radar System, Conor Willsie, Rong Chen

Honors Theses

Linear frequency modulated (LFM) radar systems are simple and easy to implement, making them ideal for inexpensive undergraduate research projects. Unfortunately, LFM radar schemes have multiple limitations that make them unviable in many real-world applications. Given the limitations of LFM radar systems, we propose a chaos-based frequency modulated (CBFM) system. In this paper, we present the theory, design, and experimental verification of a CBFM radar system that has both ranging and synthetic aperture radar imaging capabilities. The performance of our CBFM system is compared to that of the LFM system designed by MIT. We document many challenges and unforeseen obstacles …

Correcting For Terrain Interference, Attenuation, And System Bias For A Dual Polarimetric, X-Band Radar, Casey Wolsieffer

Masters Theses

This thesis outlines the procedure and theory used to calibrate the UMass eXperimental X-band Radar (UMAXX) for the purpose of monitoring meteorological events in the Pioneer Valley region. Due to the complex topography of the area, lower tilt angles are subject to partial or full beam blockage as well as ground clutter observed through the main beam or sidelobes. Additionally, there are biases internal and external to the system that impact the reflectivity and differential reflectivity measurements. These biases and corrections are addressed in this work. As the radar has been operational since September of 2018, there is ample data …

Design Of An Ultra-Wideband Frequency-Modulated Continuous Wave Short Range Radar System For Extending Independent Living, Toai-Chi Nguyen

Master's Theses

Falls in the disabled and elderly people have been a cause of concern as they can be immobilized by the fall and have no way to contact others and seek assistance. The proposed frequency modulated continuous wave (FMCW) short range radar (SRR) system, which uses ultra-wideband (UWB) signals can provide immediate assistance by monitoring and detecting fall events. The unique characteristics of this system allow for a frequency-based modulation system to carry out triangulation and sense the location of the fall through the usage of a continuous chirp signal that linearly sweeps frequency. This project focuses on the development, design …

Coffee Can Radar System, Dale Coker

Honors Theses

A Radio Detection and Ranging (“radar”) system detects a target and accurately determines its range and velocity using radio frequency (RF) waves. In the presence of a target, these RF waves are reflected, received, and processed. Until recently, radar systems have been too expensive to implement as undergraduate research projects, primarily because of the cost of the associated RF components. Recently, MIT has developed a low-cost radar system as part of an open-source course. Therefore, one objective of this project is to design and construct a radar system based on the MIT design. A further objective is to develop a …

The Umass Experimental X-Band Radar (Umaxx): An Upgrade Of The Casa Ma-1 To Support Cross-Polarization Measurements, Jezabel Vilardell Sanchez

Masters Theses

Ground-based radars are instruments commonly used to surveil the precipitation climate of the surrounding areas. Weather events are characterized by collecting backscatter data and analyzing computed products such as the Reflectivity Factor, the Doppler Velocity, the Spectrum Width, the Differential Reflectivity, the Co-polar Correlation Coefficient and the Differential Propagation Phase. The ability of the radar to transmit different polarization waves, such as horizontal and vertical polarization, allow for further analysis of the weather given the capability to perform co-polar and cross-polar measurements. The Linear Depolarization Ratio is another computed product based on the difference in power between the co-polarized and …

Mimo Radar Waveform Design And Sparse Reconstruction For Extended Target Detection In Clutter, Christopher Alan Rogers

Electrical & Computer Engineering Theses & Dissertations

This dissertation explores the detection and false alarm rate performance of a novel transmit-waveform and receiver filter design algorithm as part of a larger Compressed Sensing (CS) based Multiple Input Multiple Output (MIMO) bistatic radar system amidst clutter. Transmit-waveforms and receiver filters were jointly designed using an algorithm that minimizes the mutual coherence of the combined transmit-waveform, target frequency response, and receiver filter matrix product as a design criterion. This work considered the Probability of Detection (P _D) and Probability of False Alarm (P _FA) curves relative to a detection threshold, τ _th, Receiver Operating Characteristic (ROC), …

Insar Simulations For Swot And Dual Frequency Processing For Topographic Measurements, Gerard Masalias Huguet

Masters Theses

In Earth remote sensing precise characterization of the backscatter coefficient is important to extract valuable information about the observed target. A system that eliminates platform motion during near-nadir airborne observations is presented in this thesis, showing an improvement on the accuracy of measurements for a Ka- band scatterometer previously developed at Microwave Remote Sensing Laboratory (MIRSL). These very same results are used to simulate the reflectivity of such targets as seen from a spaceborne radar and estimate height errors based on mission-specific geometry. Finally, data collected from a dual-frequency airborne interferometer com- prised by the Ka-band system and an S-band …

Radar Detection, Tracking And Identification For Uav Sense And Avoid Applications, Erik George Moore

Electronic Theses and Dissertations

Advances in Unmanned Aerial Vehicle (UAV) technology have enabled wider access for the general public leading to more stringent flight regulations, such as the "line of sight" restriction, for hobbyists and commercial applications. Improving sensor technology for Sense And Avoid (SAA) systems is currently a major research area in the unmanned vehicle community. This thesis overviews efforts made to advance intelligent algorithms used to detect, track, and identify commercial UAV targets by enabling rapid prototyping of novel radar techniques such as micro-Doppler radar target identification or cognitive radar. To enable empirical radar signal processing evaluations, an S-Band and X-Band frequency …

Safe Pass, Alycia Riese, Julia Hariharan, Greg Synek, Jonathan Hall

Williams Honors College, Honors Research Projects

The purpose of this project is to design a sensor to be mounted on Class IV and higher vehicles to detect on-coming traffic. If traffic has been detected, the system is to warn drivers behind the stopped vehicle that passing is unsafe. The vehicle detection is to be implemented using a LiDAR detection method along with signal processing. A wireless transceiver is to transmit from the front radar module to the rear warning indicator module when the conditions are unsafe for passing. The project goals are to increase road safety and maintain traffic flow. The report details the challenges due …

Adjustment Of Rapidscat Backscatter Measurements For Improved Radar Images, Garrett Scott Mcdonald

Theses and Dissertations

RapidScat is a spaceborne wind scatterometer mounted on the International Space Station (ISS). The RapidScat mission lasted from September 2014 to November 2016. RapidScat enables the measurement of diurnal patterns of sigma-0 measurements. This capability is possible because of the non-sun-synchronous orbit of the ISS, in which the local time of day (LTOD) of sigma-0 measurements gradually shifts over time in any given location. The ISS platform is a relatively unstable platform for wind scatterometers. Because of the varying attitude of the ISS, RapidScat experiences a constant variation of its pointing vector. Variations of the pointing vector cause variations in …

Software Defined Radar For Vital Sign Detection, Chandler J. Bauder, James Bates, Steven Engel, James S. Tucker, Fangzhou Liu

Chancellor’s Honors Program Projects

No abstract provided.

Leveraging 3d Models For Sar-Based Navigation In Gps-Denied Environments, Zachary A. Reid

Browse all Theses and Dissertations

This thesis considers the use of synthetic aperture radar (SAR) to provide absolute platform position information in scenarios where GPS signals may be degraded, jammed, or spoofed. Two algorithms are presented, and both leverage known 3D ground structure in an area of interest, e.g. provided by LIDAR data, to provide georeferenced position information to airborne SAR platforms. The first approach is based on the wide-aperture layover properties of elevated reflectors, while the second approach is based on correlating backprojected imagery with digital elevation imagery. Both of these approaches constitute the system we have designated: SARNAV. Building on 3D backprojection, localization …

Impact Of Near-Field-To-Far-Field Transformation On Sar Images Formed In An Indoor Non-Anechoic Environment, Jacob D. Compaleo

Browse all Theses and Dissertations

This work investigates the impact of the near-field-to-far-field transformation (NFFFT) algorithm on phase history measurement collections completed in the Sensors and Signals Exploitation Laboratory (SSEL). SSEL is an indoor non-anechoic environ- ment that is at risk to some measurement interferences such as multiple bounces. Complete 360-degree phase history measurements of scale model aircraft are con- ducted at varying range values within the near-field limit. These measurements are calibrated with the Mie series scattering solution for a sphere. After calibration, the measurements are transformed using the NFFFT, with radar cross-section (RCS) estimated. RCS of the transformed data is compared with the …

Chaotic Based Self-Synchronization For Rf Steganography Radar/Communication Waveform, Michael A. Gonnella

Browse all Theses and Dissertations

In this project, we continue previous CSR project entitled RF Steganography based Joint Radar/Communication Waveform Design to develop a bio-inspired secure low probability detection (LPD) radio frequency (RF) waveform that can serve multiple purposes simultaneously. Previously, we have developed an RF steganography based RF waveform to conceal a secure digital communication within a linear frequency modulated (LFM) chirp radar signal. By exploiting novel reduced phase shift keying modulation and variable symbol duration, the new waveform is resistant to time domain analysis, frequency domain analysis and cyclostationary analysis. However, to demodulate the hidden communication message, the intended receiver has to know …

Implementation Of Range Autofocus For Sar Radar Imaging, Nicholas J. Testin, Philip Davis

KSU Journey Honors College Capstones and Theses

The range calculation for an FMCW radar depends on accurate linear modulation. In some circumstances, linear modulation may not be available and must be corrected for. This paper describes an autofocus technique used to correct for phase error due to non-linearities in the components of a FMCW radar. Also described here is the algorithm used in calculating the phase error and application of the phase correction with triangle modulation. Known errors were calculated at certain distances and applied to correcting the phase of data taken at similar distances. The results given were generated using a SAR working outside linear ranges.

Improvements, Algorithms And A Simulation Model For A Compact Phased-Array Radar For Uas Sense And Avoid, Adam Kaleo Roberts

Theses and Dissertations

Unmanned aerial systems (UAS) are an influential technology which can enhance life in multiple ways. However, they must be able to sense and operate safely with manned aircraft. Radar is an attractive sensor for UAS because of its all-weather performance. It is challenging, though, to meet the size, weight, and power (SWaP) limitations of UAS and especially small-UAS while still maintaining the needed sensing capability. A working FMCW radar prototype has been created which meets the SWaP requirement of small-UAS. A simulation model for the radar was developed to test the processing algorithms of the radar and proved to be …

Kasi: A Ka-Band And S-Band Cross-Track Interferometer, Gerard Ruiz Carregal

Masters Theses

A dual-frequency system is needed to better understand natural processes that constitute the environment and seasonal cycles of the Earth. A system working at two different wavelengths acquiring data simultaneously will give a valuable dataset since the conditions on the ground will be exactly the same. Hence, elements such as wind, soil moisture or any other changes on the ground will not interfere in the mea- surements. This thesis explains how an S-band radar was built and tested. Moreover, the experiments done with a Ka-band radar used as a scatterometer are explained as well as the data processing and analysis. …

Topography Measurements Using An Airborne Ka-Band Fmcw Interferometric Synthetic Aperture Radar, Kan Fu

Doctoral Dissertations

Radar interferometry at millimeter-wave frequencies has the ability of topography measurement of different types of terrain, such as water surfaces and tree canopies. A Ka-band interferometric radar was mounted on an airborne platform, and flown over the Connecticut river region in western Massachusetts near Amherst on June 11, 2012. More than 20 Gigabytes of raw data was recorded. This dissertation outline presents the results of the data processing, which includes (1) the estimation and removal of the embedded high frequency phase error in the raw data; (2) the synthetic aperture processing; (3) the interferometric processing. The digital elevation model (DEM) …

Performance Simulation And Optimization Of A Simultaneous Transmit And Receive Phased Antenna Array Using Adaptive Beamforming And Genetic Algorithm Techniques, Ian Thomas Cummings

Dissertations, Master's Theses and Master's Reports

The development of simultaneous transmit and receive capabilities is on the cutting-edge of research in phased array technology [1, 2, 3]. The large disparity in power between the transmitted and received signals in antenna systems has traditionally prevented operation in a simultaneous mode. However, simultaneous transmit and receive offers great opportunities for increased capabilities and performance in communications, radar, and electronic warfare applications [3]. This technology will be made feasible by realizing a high level of isolation between the transmitted and received signals through a variety of techniques. This work explores the feasibility of choosing non-standard array partitions that--when paired …

Data Logging System For A Synthetic Aperture Radar Unit, Nicholas J. Testin, Philip Davis, Ian Dorell, Alexander Gillespie

KSU Journey Honors College Capstones and Theses

A small, existing radar unit lacked the ability to automatically store the data it was receiving, which made its use clunky and cumbersome. A system was constructed to allow an on-board microprocessor to track distance traveled, and automatically store the data output from the radar unit to a portable memory unit for later data processing. Distance traveled is determined using a specially designed mobile cart, which electronically converts the rotation of a wheel into an electrical signal while also providing stability for taking accurate radar measurements. The output data from the radar unit is stored as a properly-formatted sound file …

Scaled Synthetic Aperture Rader Development, Jason Garvey Schray

Master's Theses

Several previous Cal Poly thesis projects involve synthetic aperture radar (SAR), automatic target recognition (ATR), and tracking. SAR data was either accessed from a publicly available database or generated using complex computer modeling software. The motivation for this dual thesis project is to design and construct a scaled SAR system to support Cal Poly radar projects. Ideally this is a low-cost, high resolution SAR architecture that produces raw range Doppler data for any desired target area. To that end, a scaled SAR system was successfully designed, built, and tested. The current SAR system, however, does not perform azimuthal compression and …

Evaluating Features For Broad Species Based Classification Of Bird Observations Using Dual-Polarized Doppler Weather Radar, Sheila Werth

Masters Theses

Wind energy is one of the fastest-growing segments of the world energy market; however, wind energy facilities can have detrimental effects on wildlife, especially birds and bats. The ability to monitor vulnerable species in the vicinity of proposed wind sites could enable site selection that favors more vulnerable species, but current monitoring tools lack this classification capability. This work analyzes polarimetric and Doppler measurements of migrating birds for species based variation.

A novel two stage feature extraction technique was developed to enable comparison between birds. Stage one involves mapping time changing radar measurements to the birds behavioral state in time …

The Effects Of Antenna Coupling In A Mimo Radar System, Benjamin T. Arnold

Theses and Dissertations

A mathematical model for a multiple-input multiple-output radar system is presented. The model is used to track signals through the system in order to identify the impact of antenna array mutual coupling on radar system performance. Simulations using the model provide quantitative assessment of the performance degradation as a function of antenna coupling strength. Specifically, the results show that coupling can cause a target to appear at an angle notably different than its actual angle and can cause an increase in the side lobe level. A compensation technique is presented that completely removes these effects for practical levels of coupling. …

Applications In Low-Power Phased Array Weather Radars, Robert A. Palumbo Jr

Doctoral Dissertations

Low-cost X-band radars are an emerging technology that offer significant advantages over traditional systems for weather remote sensing applications. X-band radars provide enhanced angular resolution at a fraction of the aperture size compared to larger, lower frequency systems. Because of their low cost and small form factor, these radars can now be integrated into more research and commercial applications. This work presents research and development activities using a low-cost, X-band (9410 MHz) Phase-Tilt Radar. The phase-tilt design is a novel phased array architecture that allows for rapid electronic scanning in azimuth and mechanical tilting in elevation, as a compromise between …

Modular Multi-Signal Tracking Pulse Descriptor Word (Pdw) Generator With Field Programmable Gate Array (Fpga) Implementation, Justin Darrell Pelan

Browse all Theses and Dissertations

As signal spectra become dense, the task of tracking and identifying radars becomes increasingly cumbersome. The variety of radars in modern theaters of war compound the task due to simultaneous operation. Real-time processing of large data sets prove difficult for sequential systems, and the parallelism of Field Programmable Gate Arrays (FPGAs) becomes an attractive option. To mitigate the increasing complexity of this task, this design proposes an FPGA architecture to produce pulse descriptor words (PDW) for up to eight independent radio frequency signals that can be used in near-real-time processing. Focusing on digital hardware techniques and modular design allow for …