Engineering Commons^™

Generalized Model To Enable Zero-Shot Imitation Learning For Versatile Robots, Yongshuai Wu

Master's Theses

The rapid advancement in Deep Learning (DL), especially in Reinforcement Learning (RL) and Imitation Learning (IL), has positioned it as a promising approach for a multitude of autonomous robotic systems. However, the current methodologies are predominantly constrained to singular setups, necessitating substantial data and extensive training periods. Moreover, these methods have exhibited suboptimal performance in tasks requiring long-horizontal maneuvers, such as Radio Frequency Identification (RFID) inventory, where a robot requires thousands of steps to complete.

In this thesis, we address the aforementioned challenges by presenting the Cross-modal Reasoning Model (CMRM), a novel zero-shot Imitation Learning policy, to tackle long-horizontal robotic …

Time-Domain Evaluation Of Atmospheric Ducting Effects On X-Band Propagation Over Water, Jack A. Gallegos

Master's Theses

The marine atmospheric boundary layer (MABL) is the region of atmosphere that interacts with the ocean surface. The atmospheric variability (i.e. temperature and relative humidity) in this region can result in rapid changes in the refractive index with increasing height from the sea surface. The complex region can result in non-standard propagation of electromagnetic (EM) waves beyond the horizon under atmospheric ducting conditions. However, when ducting layers are not present, EM waves are limited to line-of-sight transmission. Atmospheric ducting research is typically conducted using radio frequencies in the X-band (around 8-12 GHz) due to its impact on performance of marine …

X-Band Rf Transmitter Design For Multi-Purpose Small Satellite Communication Operations, Omer F. Gumus

Master's Theses

This thesis provides a description of the analysis, design, and tests of an X-band RF Transmitter communication system for small satellites. X-band transmitter systems are becoming popular in the upcoming deep space missions. Most of the deep-space ground stations have been using X-band frequencies to receive or transmit signals. The X-band (<10 GHz) can offer lower atmospheric losses and up to a couple of Mbps data rates for multiple satellite operations. Nowadays, many small satellites have been using frequency bands such as VHF, UHF, L, and S-band frequencies for communication. From deep space to the ground station, the low-frequency ranges are inadequate in providing Mbps level data rates and enough bandwidth for deep space missions.

The main focus of this thesis was the development of the subsystems such as gain block amplifier, Mixer, Bandpass Filter, and RF power amplifier. The subsystems were designed separately, then they were connected together to perform an end-to-end system test. One of the thesis aims is to design …

Indoor Positioning Using Synchronized Ultrasonic Ofdma Signals, Julian Bartolone

Master's Theses

This paper proposes a method of short-range indoor localization using differential phase measurements of synchronized two-tone ultrasonic signals in an Orthogonal Frequency Multiple Access (OFDMA) scheme. This indoor positioning system (IPS) operates at an ultrasonic frequency of approximately 40kHz and synchronizes using an infrared signal. The OFDMA scheme allows for a receiver to process the signals from multiple transmitters continuously without the signals interfering with each other. The phases of the signals are measured using Goertzel Filters, allowing for low-complexity frequency content analysis. A MATLAB simulation using the proposed localization method is performed using four transmitter nodes in the corners …

Scalable Cognitive Radio Network Testbed In Real Time, Kevin Z. Yu

Master's Theses

Modern society places an increasingly high demand on data transmission. Much of that data transmission takes place through communication over the frequency spectrum. The channels on the spectrum are limited resources. Researchers realize that at certain times of day some channels are overloaded, while others are not being fully utilized. A spectrum management system may be beneficial to remedy this efficiency issue. One of the proposed systems, Cognitive Radio Network (CRN), has progressed over the years thanks to studies on a wide range of subjects, including geolocation, data throughput rate, and channel handoff selection algorithm, which provide fundamental support for …

An Exploratory Study Of Pulse Width And Delta Sigma Modulators, Logan B. Penrod

Master's Theses

This paper explores the noise shaping and noise producing qualities of Delta-Sigma Modulators (DSM) and Pulse-Width Modulators (PWM). DSM has long been dominant in the Delta Sigma Analog-to-Digital Converter (DSADC) as a noise-shaped quantizer and time discretizer, while PWM, with a similar self oscillating structure, has seen use in Class D Power Amplifiers, performing a similar function. It has been shown that the PWM in Class D Amplifiers outperforms the DSM [1], but could this advantage be used in DSADC use-cases? LTSpice simulation and printed circuit board implementation and test are used to present data on four variations of these …

Simulation Of An Sp8t 18 Ghz Rf Switch Using Smt Pin Diodes, Andre De Souza Vigano

Master's Theses

Radio frequency (RF) and microwave switches are widely used in several different applications including radar, measurement systems, telecommunications, and other areas. An RF switch can control a radar’s transmit vs. receive mode, select the operating band, or direct an RF signal to different paths. In this study, a single pole eight throw (SP8T) switch using only Surface Mount (SMT) components is designed and simulated in Keysight’s Advanced Design System (ADS). Single pole eight throw is defined as one input and eight possible outputs. A star network configuration with series-shunt PIN diode switches is used to create the 8-way RF switch. …

Iot Camera System For Monitoring Strawberry Fields, Simon Schoennauer

Master's Theses

A wireless imaging system for monitoring strawberry fields provides enough quality image data for computer vision algorithms to make meaningful yield predictions. This report contains a design for a wireless sensor network modified with mesh networking techniques to extend coverage range and a solar energy harvesting system to improve sensor node lifetime. A two hop system with six nodes is implemented in a laboratory environment validating the communication systems integrity over an 800’ range. Moving from a primary battery system to solar energy harvesting increases the module lifetime indefinitely.

Distance Estimation Using Ofdm Signals For Ultrasonic Positioning, Kyman Huang

Master's Theses

This paper describes a method of estimating distance via Time-of-Flight (TOF) measurement using ultrasonic Orthogonal Frequency Division Multiplexing (OFDM) signals. Using OFDM signals allows the signals and their sub-carriers to remain orthogonal to each other while continuously transmitting. This estimation method is based on the change of phase of a traveling wave as it propagates through a medium (air for ultrasonic signals). By using signals containing multiple tones, the phase change between each frequency component is slightly different. This phase difference is dependent on the distance traveled and can thus be used to estimate distance. This paper studies the impact …

The Design, Testing, And Analysis Of A Constant Jammer For The Bluetooth Low Energy (Ble) Wireless Communication Protocol, Aiku Shintani

Master's Theses

The decreasing cost of web-enabled smart devices utilizing embedded processors, sensors, and wireless communication hardware have created an optimal ecosystem for the Internet of Things (IoT). IEEE802.15.4, IEEE802.11ah, WirelessHART, ZigBee Smart Energy, Bluetooth (BT), and Bluetooth Low Energy (BLE) are amongst the most commonly used wireless standards for IoT systems. Each of these standards has tradeoffs concerning power consumption, range of communication, network formation, security, reliability, and ease of implementation. The most widely used standards for IoT are Bluetooth, BLE, and Zigbee. This paper discusses the vulnerabilities in the implementation of the PHY and link layers of BLE. The link …

Indoor Positioning Using Acoustic Pseudo-Noise Based Time Difference Of Arrival, Nicholas J. Luong

Master's Theses

The Global Positioning System (GPS) provides good precision on a global scale, but is not suitable for indoor applications. Indoor positioning systems (IPS) aim to provide high precision position information in an indoor environment. IPS has huge market opportunity with a growing number of commercial and consumer applications especially as Internet of Things (IoT) develops. This paper studies an IPS approach using audible sound and pseudo-noise (PN) based time difference of arrival (TDoA). The system’s infrastructure consists of synchronized speakers. The object to be located, or receiver, extracts TDoA information and uses multilateration to calculate its position. The proposed IPS …

Development And Characterization Of An Iot Network For Agricultural Imaging Applications, Jacob D. Wahl

Master's Theses

Smart agriculture is an increasingly popular field in which the technology of wireless sensor networks (WSN) has played a large role. Significant research has been done at Cal Poly and elsewhere to develop a computer vision (CV) and machine learning (ML) pipeline to monitor crops and accurately predict crop yield numbers. By autonomously providing farmers with this data, both time and money are saved. During the past development of a prediction pipeline, the primary focuses were CV and ML processing while a lack of attention was given to the collection of quality image data. This lack of focus in previous …

Involuntary Signal-Based Grounding Of Civilian Unmanned Aerial Systems (Uas) In Civilian Airspace, Keith Conley

Master's Theses

This thesis investigates the involuntary signal-based grounding of civilian unmanned aerial systems (UAS) in unauthorized air spaces. The technique proposed here will forcibly land unauthorized UAS in a given area in such a way that the UAS will not be harmed, and the pilot cannot stop the landing. The technique will not involuntarily ground authorized drones which will be determined prior to the landing. Unauthorized airspaces include military bases, university campuses, areas affected by a natural disaster, and stadiums for public events. This thesis proposes an early prototype of a hardware-based signal based involuntary grounding technique to handle the problem …

Analog Single Sideband-Pulse Width Modulation Processor For Parametric Acoustic Arrays, Vikrant A. Marathe

Master's Theses

Parametric acoustic arrays are ultrasonic-based loudspeakers that produce highly directive audio. The audio must first be preprocessed and modulated into an ultrasonic carrier before being emitted into the air, where it will self-demodulate in the far field. The resulting audio wave is proportional to the double time-derivative of the square of the modulation envelope. This thesis presents a fully analog processor which encodes the audio into two Pulse Width Modulated (PWM) signals in quadrature phase and sums them together to produce a Single Sideband (SSB) spectrum around the fundamental frequency of the PWM signals. The two signals are modulated between …

Development Of A Myoelectric Detection Circuit Platform For Computer Interface Applications, Nickolas Andrew Butler

Master's Theses

Personal computers and portable electronics continue to rapidly advance and integrate into our lives as tools that facilitate efficient communication and interaction with the outside world. Now with a multitude of different devices available, personal computers are accessible to a wider audience than ever before. To continue to expand and reach new users, novel user interface technologies have been developed, such as touch input and gyroscopic motion, in which enhanced control fidelity can be achieved. For users with limited-to-no use of their hands, or for those who seek additional means to intuitively use and command a computer, novel sensory systems …

Adaptation Of Vt-Dbr Lasers For Lidar, Luke Horowitz

Master's Theses

Vernier Tuned Distributed Bragg Reflector (VT-DBR) lasers have had great success in the field of Swept-Source Optical Coherence Tomography (SS-OCT) due to their continuous and nearly 40 nm wavelength tuning range in a single longitudinal mode. Fast sweeps allow for real time imaging with micrometer resolution at a distance of a few centimeters. While this laser has proven quite useful as a medical imaging tool via OCT, it has yet to similarly prove itself for general light detection and ranging (LIDAR) applications due to range limitations that arise from a finite laser coherence length. The goal of this thesis is …

Design And Verification Of A Labview Automated Antenna Radiation Pattern Measurement System, Dylan C. Bloom

Master's Theses

In 2014, Toyon Research Corporation donated a 6’x6’x8’ anechoic chamber to the Cal Poly EE department to advance student education in the areas of antennas and wireless communications. An anechoic chamber is a room designed to suppress electromagnetic radiation reflections so that accurate measurement of radio frequency (RF) systems such as wireless radios and antennas can take place. Despite the fact that Cal Poly already has a larger anechoic chamber, primarily used for antenna characterization, it is the purpose of this project to design, code, and equip the new chamber so that it performs at least as good, or better …

The Design, Building, And Testing Of A Constant On Discreet Jammer For The Ieee 802.15.4/Zigbee Wireless Communication Protocol, Alexandre J. Marette

Master's Theses

As wireless protocols become easier to implement, more products come with wireless connectivity. This latest push for wireless connectivity has left a gap in the development of the security and the reliability of some protocols. These wireless protocols can be used in the growing field of IoT where wireless sensors are used to share information throughout a network. IoT is being implemented in homes, agriculture, manufactory, and in the medical field. Disrupting a wireless device from proper communication could potentially result in production loss, security issues, and bodily harm. The 802.15.4/ZigBee protocol is used in low power, low data rate, …

Vehicle Pseudonym Association Attack Model, Pierson Yieh

Master's Theses

With recent advances in technology, Vehicular Ad-hoc Networks (VANETs) have grown in application. One of these areas of application is Vehicle Safety Communication (VSC) technology. VSC technology allows for vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications that enhance vehicle safety and driving experience. However, these newly developing technologies bring with them a concern for the vehicular privacy of drivers. Vehicles already employ the use of pseudonyms, unique identifiers used with signal messages for a limited period of time, to prevent long term tracking. But can attackers still attack vehicular privacy even when vehicles employ a pseudonym change strategy? The major contribution …

Rf Front End For An Integrated Silhouette Capture And Boundary Detection Frequency Modulated Continuous Wave Ultra-Wideband Radar System For The Extension Of Independent Living, Adrian Smet

Master's Theses

Limitations of current eldercare monitoring systems leave a need for new solutions. A monitoring system based on a frequency modulated continuous wave ultra-wideband short-range radar is proposed for this application. The complete proposed monitoring system is comprised of four blocks: boundary detection, silhouette capture, human identification, and data transmission. This paper develops the RF front end hardware for the silhouette capture subsystem.

System requirements are derived for the silhouette capture subsystem. An architecture for the RF front end is designed, and required individual component specifications are determined. Components are selected off the shelf or custom designed for each socket. Full …

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

Master's Theses

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

Master's Theses

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

Master's Theses

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, 2.4GHz Dipole …

Uhf Rfid Antenna Impedance Matching Techniques, Kamron Sockolov

Master's Theses

Radio Frequency Identification (RFID) systems use electromagnetic signals to wirelessly identify and track RFID-tagged objects. A reader transmits a carrier wave request signal to an RFID tag, which then transmits a unique identification signal back to the reader. Applications include supply chain inventory management, automated toll booth fee systems, sports event timing, restricted access control, pet monitoring and retail theft prevention. An RFID tag includes an antenna connected to a Radio Frequency Integrated Circuit (RFIC). RFID tags in the ultra-high frequency (UHF), industrial, scientific and medical (ISM) 902-928MHz band and global Electronic Product Code (EPC) 860‑960MHz band are powered passively …

Thermal Evolution Of Moon, Arshdeep Singh Gill

Master's Theses

In August, 2014 three experiments were conducted using infrared systems deployed at White Mountain Research center, CA. The data was acquired for the whole month of August. Teams of 3-4 students from Cal Poly San Luis Obispo and UC Santa Barbara were stationed at the research center for 2-3 days to operate the equipment. The three experiments were:(1) creating spatial-temporal time series of lunar surface temperatures;(2) identifying atmospheric meteor trails;(3) search for meteor impacts on the Moon surface. Out of the three this thesis focusses on experiment 1 and the results from this experiment could also help with the other …

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 …

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 …

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 …

Design And Fabrication Techniques Of Devices For Embedded Power Active Contact Lens, Errol Heradio Leon

Master's Theses

This thesis designed and fabricated various devices that were interfaced to an IC for an active contact lens that notifies the user of an event by detection of an external wireless signal. The contact lens consisted of an embedded antenna providing communication with a 2.4GHz system, as well as inductive charging at an operating frequency of 13.56 MHz. The lens utilized a CBC005 5µAh thin film battery by Cymbet and a manufactured graphene super capacitor as a power source. The custom integrated circuit (IC) was designed using the On Semiconductor CMOS C5 0.6 µm process to manage …

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. …