Systems and Communications Commons^™

Autonomous Terrain-Mapping Robot For Search And Rescue, Soumil Joshi, Seann Calub

Electrical Engineering

This report documents the design, modular testing, and challenges faced while developing an autonomous terrain-mapping robot intended to navigate to a destination waypoint and deliver a small payload for search-and-rescue applications. The system combines a LiDAR sensor, an IMU sensor, and a Raspberry Pi 3B as the onboard processor, and an ESP32 microcontroller interfacing with motor drivers over a four-wheel chassis. A companion mobile application was developed to enable remote control and monitoring of the robot over a WiFi hotspot connection. A lithium-ion battery pack supplies power to all onboard components, with power budgets verified against component datasheets. Testing progresses …

Archimedean Spiral Antenna Array With Klopfenstein And Exponential Tapered Balun Feeds, Leo Joseph Alvelais Iv, Paul Obrecht, Naguib Abdulla, Preston Mavady, Collin Fan

Electrical Engineering

This project presents the design, fabrication, and experimental evaluation of a broadband 3x3 Archimedean spiral antenna array tile for 2.8-3.8 GHz. Each element combines a two-arm spiral on Rogers RO4350B, a printed 50 to 150 Ω tapered balun, and a conductive backplane. Klopfenstein and Exponential feed implementations were modeled in Ansys HFSS, generated and tuned with automated scripting, fabricated, and evaluated with calibrated network and anechoic-chamber measurements. The Klopfenstein-fed hardware met the -10 dB input-reflection criterion across the project band. The exponential array provided a broad matched response but reached approximately -8 dB near 2.95 GHz. Measured center-element patterns retained …

Discrete S-Band Low-Noise Amplifier Designs For High Data-Rate Cubesat Uplink, Alejandro Martin Cosper, Alejandro Cosper

Master's Theses

In the world of small satellites, there is growing interest in higher-data-rate systems and the technologies that enable them. Due to limitations in the extremely reliable and proven Ultra-High Frequency (UHF) systems, the current CubeSats developed by the Cal Poly CubeSat Laboratory operate at 9600 Baud. However, the low Baud rate is rooted in decades of proven flights and is very resistant to many forms of signal degradation. While a slow but simple system was critical to past successes, future satellite payloads may require higher data rates to drastically reduce the number of passes needed to transfer large amounts of …

A Study On Quantization And Hardware Cost Tradeoffs In A 5g Nr Ldpc Decoder On Fpga, Giancarlo Acosta

Master's Theses

The fixed-point implementation of a 5G New Radio LDPC decoder forces a tradeoff between precision and hardware cost, governed by the variable node word length W_L, the check node message width W_R, and the normalized min-sum correction factor α. This thesis characterizes how these three parameters affect both error correction performance and FPGA resource utilization for an LDPC decoder on an established LDPC decoder architecture. A bit-accurate MATLAB core model records bit error rate (BER) and frame error rate (FER) while a verified HDL Coder model generates synthesizable VHDL for Vivado synthesis, and both are swept …

Performance Evaluation Of Roadside Unit-Assisted Wireless Communication For Connected Vehicles, Keyrollos A. Hanna, Ethan M. Nguyen

Electrical Engineering

This project presents the design and implementation of a wireless communication network intended to improve situational awareness between vehicles and reduce the likelihood of multivehicle collisions. Two TurtleBot3 Burger platforms equipped with Raspberry Pi computers were used to simulate vehicles operating within a shared environment. Communication latency and packet loss were evaluated under multiple operating conditions, including direct vehicle-to-vehicle communication and communication assisted by a roadside unit (RSU). The results were analyzed to determine whether the proposed system could transmit warning messages with sufficient speed and reliability for collision prevention applications. The project demonstrates the feasibility of low-cost vehicle communication …

Wildlife Tracking Via Uav&Rf, Nam Ah Nguyen

Electrical Engineering

Animal tracking collars transmit very-high-frequency (VHF) beacon signals so researchers can locate tagged wildlife in terrain where direct visual tracking is difficult. This project develops a radio-frequency (RF) wildlife tracking prototype in which a UAV carries a receiving antenna and receiver over the search area to detect the collar signal and send measurements to a ground station. A transmitter test device was built to emulate a tracking collar. An STM32 microcontroller reads keypad input, controls a digital-to-analog converter (DAC), tunes a voltage-controlled oscillator (VCO) to the selected VHF frequency, and sends the RF signal through an amplifier and antenna. The …

Portable Food Pasteurization Using Pulsed Electric Fields (Pef), Thomas E. Mcmillan Iii

Electrical Engineering

Foodborne illnesses remain a significant public health concern, motivating continued development of alternative food pasteurization technologies. Pulsed electric field (PEF) treatment is a non-thermal pasteurization method that inactivates microorganisms through electroporation while minimizing thermal degradation of food products. The long-term objective of this project was development of a portable PEF food pasteurization system.

An iterative design approach was used to investigate generation of the high-voltage pulses required for PEF treatment. Multiple pulse forming network topologies were evaluated through simulation, leading to selection of a solid-state Marx generator architecture. A low-voltage five-stage prototype was designed, constructed, and tested to validate the …

Wireless Communication In Autonomous Vehicles, Kaylie Bao, Nicholas Andrews, Mark Negus

Electrical Engineering

This project focuses on developing and testing a vehicle-to-everything (V2X) communication system using Dedicated Short Range Communications (DSRC) based on the IEEE 802.11p standard. The system uses the NXP i.MX 8XLite V2X Evaluation Kit, which includes the SAF5400 modem for wireless communication in the 5.9 GHz band.

The main goal of this project was to establish reliable communication between two V2X evaluation boards and to verify that custom, user-defined data could be transmitted between them. Through iterative testing, we were able to successfully send and receive custom 802.11 frames using the provided command-line tools and achieve consistent communication between nodes. …

Lora Radio Propagation & Antenna Design For Freight Trains, Cesar Chavez, Marlon Jennson Hernandez

Electrical Engineering

Freight-train environments present significant challenges for wireless communication due to large metallic structures, varying cargo types, and changing antenna orientations that can degrade radio-frequency propagation. This project evaluated the performance of LoRa-based communication links intended for End-of-Train (EOT) and Head-of-Train (HOT) systems operating at 915 MHz. Field testing was conducted to characterize antenna performance using metrics including received signal strength indicator (RSSI), signal-to-noise ratio (SNR), and communication range. Experimental results showed that antenna polarization and directivity significantly affect communication performance in freight-train environments. Directional antennas provided improved signal strength when properly aligned but experienced performance degradation as antenna orientation changed. …

Space Quacker Advanced Development (Squad): Lora Modulation On A Leo Cubesat Mission For Evaluation Of 916 Mhz Uplink, Samantha Brunton

Master's Theses

The LoRa Modulation format was developed by SEMTECH in 2018 and has revolutionized terrestrial Internet of Things (IoT) networks. LoRa (Long Range) has been successfully demonstrated as a long-range, low-data-rate communication modulation format and packet protocol for low-power terrestrial applications. LoRa offers low power consumption, low cost, robust signal sensitivity, and long communication range. Recently, interest has grown in using LoRa communication in Low Earth Orbit (LEO) satellite systems, especially for global IoT connectivity. Previous studies have investigated the theoretical feasibility and simulated the performance of LoRa satellite communication. Companies such as Lacuna Space have demonstrated the practical potential of …

Deterministic Methods To Improve The Field-Of-View For Direction Finding Using Sparse Digital Arrays, Nolan J. Egging

Master's Theses

Direction finding algorithms are used with digital phased arrays to determine the incoming angle of arrival (AoA) of an incident signal. These algorithms, and direction finding as a whole, have a wide range of civilian and military applications from radar, electronic reconnaissance, mobile communication, et cetera. However, for situations where the spacing between antenna elements needs to be large, gating lobes appear in the radiation pattern of analog arrays. This work demonstrates that for digital beamforming algorithms, the field of view (FoV) of a uniform linear digital array matches the grating lobe free range of a similarly spaced analog array. …

Building A Smart Transportation Network To Prevent Multi-Vehicle Collisions During Sudden Slowdowns, Leo Huang, Patrick Zhao

College of Engineering Summer Undergraduate Research Program

This proposed SURP project aims to design and evaluate a smart transportation network capable of preventing multiple-vehicle collisions due to sudden slowdowns in traffic. This project will simulate abrupt braking scenarios and implement adaptive vehicle-to-vehicle (V2V) communication protocols. By enhancing real-time awareness and responsiveness among vehicles, the system will reduce pileup risks and improve road safety.

Building Pathways To Computer Science Careers For Latinx Students Through Multilingual Collaborative Block-Based Programming, Cis Garcia, Noemi Corona Calvario

College of Engineering Summer Undergraduate Research Program

The underrepresentation of Latinx students in computer science highlights the need for innovative and inclusive educational approaches. This project addresses challenges such as limited access to educational resources and the demand for multilingual learning tools by developing a co-located, collaborative, game-based programming environment. Designed for use on phones, tablets, and laptops, this tool supports English, Spanish, and Mixtec, facilitating broader engagement. By promoting peer collaboration and interactive learning, our approach challenges traditional notions of solitary programming and reinforces the idea that expertise is shared, fostering an inclusive and equitable learning environment.

Owl Solar-Powered Link: Duck Radio Mesh For Autonomous Monitoring, Jaden Tran, Shane Williams

Electrical Engineering

The Solar Duck Sensor Node transforms a standard DuckLink into a fully self-sustaining environmental monitor. A compact solar panel / power bank module plugs into the power ports of both the DuckLink and the Raspberry Pi Zero 2 W, keeping them charged through day-night cycles. The Pi Zero 2 W will perform local processing of sensor data. Sensor output will come from the Raspberry Pi AI Camera and its object detection capabilities. This output will be distilled into metadata and advertised over BLE. The DuckLink captures these packets, encapsulates them into LoRa payloads, and forwards them across the ClusterDuck mesh …

Streamlined Intelligence: Resource-Efficient Machine Learning For 5g Nr V2v Channel Equalization, Jacqueline G. Radding

Master's Theses

As autonomous vehicles continue to evolve, reliable and efficient real-time communication between vehicles is essential for safety and performance. This thesis explores Streamlined Intelligence: Resource Efficient machine learning for 5G NR V2V Channel Equalization, focusing on lightweight random forest decision tree models to address the challenges of channel equalization in 5G New Radio (NR) vehicle to vehicle (V2V) systems. Using orthogonal frequency division multiplexing (OFDM) with QPSK modulation, the study simulates data transmission in nonlinear channels characterized by obstructions, Doppler shifts, and fading. Decision trees are proposed as a computationally efficient alternative to other machine learning methods while being compared …

Coherent Synchronization For Distributed Digital Phased Arrays, Zachary C. Numa

Master's Theses

Distributed digital phased arrays are rising technologies that help enable applications such as search and rescue operations, wireless communication, radar navigation, and military operations, among many others. Due to their improved angular resolution, digital phased arrays offer superior direction-finding capabilities compared to traditional analog phased array systems. However, this improvement comes at the cost of increased complexity—specifically, the need for precise synchronization of phase, time, and frequency across physically separated nodes. Without synchronization, the distributed phased array's gain and direction-of-arrival (DoA) estimations deteriorate significantly.

There are multiple aspects to implementing and synchronizing a non-stationary distributed digital phased array. This research …

Open Source Microgrid Integration, Zachary J. Kwast

Master's Theses

Microgrids are small-scale electrical systems that operate in tandem with a centralized grid to provide power to a smaller group of target devices. These microgrids are used for a wide range of different purposes, which invites the need for a generalized model that can be tweaked for a variety of uses. This document goes over the theory used to design an open source AC and DC microgrid meant for use by anyone. The microgrid is created using a Raspberry Pi that controls two different power converters so that a wide range of voltage and current characteristics can be achieved. These …

Single-Sided Hearing Assistance Application, Harryson Nguyen, Jp Haratani

Electrical Engineering

The product is a hearing assistance smartphone application which aims to improve the quality of life of people with single-sided hearing loss/deafness by providing them with a cheaper and more reliable alternative to medically-prescribed hearing aids. Due to development setbacks, the product instead uses open-ear earbuds. Since the earbuds are not directly inserted into the user’s ear canals, they will not obstruct the hearing of the user’s non-deaf ear, and the user will still be able to hear the sounds that come from their non-deaf side. Some users may find that Bluetooth earbuds can be quite expensive, but are ultimately …

Wireless Communication In Autonomous Vehicles, Ethan Paul Spalard, Alan Rubalcava, Jarnail Singh Sanghera

Electrical Engineering

This project focuses on building a realistic, standards based V2X communication platform using DSRC (IEEE 802.11p) to support future autonomous vehicle control research. The system is built around commercial off-the-shelf (COTS) hardware, specifically the NXP i.MX 8XLite – V2X Evaluation Kit, which integrates an automotive-grade processor and the SAF5400 V2X modem to handle low-level DSRC transmission in the 5.9 GHz band.

We successfully completed the hardware bring-up, verified over-the-air communication between two nodes, and performed initial RF characterization using a spectrum analyzer. The SAF5400 was confirmed to operate on all seven DSRC channels (172–184), maintaining the correct 10 MHz bandwidth …

Direction Finding From Aerial Platforms With Amateur Radio Arrays, Ben Duval Iii, Esteban Perez

Electrical Engineering

This senior project presents the development of a communication network designed to remotely control and program a distributed digital antenna array for autonomous synchronization and calibration. The system facilitates command transmission using a custom BPSK communication protocol operating in the UHF band (430–450 MHz) and employs a two-tone waveform to extract frequency, phase, and timing offsets between array nodes. These offsets are critical for aligning received signals in preparation for digital beamforming. The array comprises four nodes: three aerial units and one ground-based control unit. Each node is built using a LimeSDR Mini 2.0, Raspberry Pi, portable battery pack, and …

Digital Drone Arrays: Two-Tone Communication, Armin Behbahani, Alejandro Martin Cosper, Landon Leroy John Foster, Mont Ziadoon Murad

Electrical Engineering

Over the last few years, there has been great interest in distributed antenna arrays. These arrays require each element to be precisely located and synchronized with each other in time, phase, and frequency. To this end, a drone-mounted, two-tone communication system was developed. It uses a transmit-retransmit-receive architecture, which obtains all of the necessary data required to compute and correct the phase, frequency, and time differences between each element while estimating distance. When integrated into a distributed array of drones, this two-tone communication system will be essential for reliable operation.

Project Owl: Quad Rc2, Ethan Cy Zane

Electrical Engineering

Quad RC2 is a new radio designed to be compatible with the Cluster Duck Protocol (CDP). It must be able to act as all parts of the mesh network and be able to find its location with GPS. Much of the RC2 effort is already completed. This project ports the previously developed firmware to the new board and runs tests to assess its capabilities.

An Analysis Of The Power Consumption Of Various Computer Vision Machine Learning Techniques On A Microcontroller Utilizing The Clusterduck Protocol, Kaveh Shafiei

Electrical Engineering

Constant data processing is essential for effective data collection, particularly in remote and hard-to-reach areas. The need for efficient, autonomous data acquisition and transmission is increasingly addressed by integrating machine learning within larger communication networks. This paper explores the application of machine learning techniques with Internet of Things (IoT) mesh networks. Utilizing the LoRa communication protocol, data is captured and analyzed on an edge device and transmitted to a larger communication network. The ClusterDuck Protocol (CDP), developed by OWL Integrations, serves as an IoT mesh network designed to allow for communication in areas lacking traditional static infrastructure such as WiFi …

Compact, Low-Power Underwater Acoustic Modem Characterization And Sensing Network Node Implementation, Lucas W. Lucia

Master's Theses

There is a growing market for compact, power-efficient underwater communication technology. Due to the limited propagation of electromagnetic waves through water, modulated acoustic waves have emerged as an effective means of wireless communication underwater. In decades past, many acoustic modems had been developed primarily for defense customers in larger systems functioning at high power. In recent years, smaller, relatively inexpensive acoustic modems have become available on the market—but data on their performance in a real-world environment is scarce. Companies such as OWL Integrations are interested in employing such acoustic modems as part of sensing networks across multiple mediums. For such …

Study On The Application Of Smart Electric Meters For Secondary Voltage Protection, Jayaditya Sisodia

Master's Theses

The purpose of our research is to utilize PG&E’s Smart Meters installed across California to protect the Secondary Voltage delivered to the meter. This means detecting electrical faults between the utility’s distribution transformer and the installed Smart Meter. Our goal is to propose and implement various solutions through additional devices and protocols to detect and prevent these faults, communicate them with the meter, and forward fault information to the utility. A device will be designed to be installed on the transformer, detect faults, shut off power transmission, and communicate to the meter via fiber optic cable. Research will then be …

Remote Monitoring And Control Of Protection Relays Via Programmable Logic Controller, Rio Mcgown-Kauffman

Master's Theses

The purpose of this study is to explore the ability of a programmable logic controller (PLC) to wirelessly monitor and control power protection relays. The technologies surrounding power protection and industrial automation are ever evolving and have developed significantly in recent history. Industrial power applications call for consistent condition monitoring and status updates for various high-importance components. The high-importance components have power protection schemes that are managed by digital relays to trip circuit breakers in fault or unsafe operating conditions. The smart relays have a wide range of capabilities, including communications. Cal Poly assembled a collection of relays from Schweitzer …

Remote Operated Amateur Radio Using Raspberry Pi And Limesdr, Esteban I. Perez

College of Engineering Summer Undergraduate Research Program

This project presents the design and implementation of a portable, remotely programmable amateur radio system operating on the 2-meter and 70-cm bands. The system utilizes Raspberry Pi 5 and LimeSDR hardware to facilitate communication between aerial and ground units, allowing for efficient transmission and reception of synchronization and calibration waveforms. A custom communication protocol incorporating BPSK modulation and a two-tone signaling mechanism enables time-of-flight measurements for calculating distances between nodes. This low-cost solution has potential applications in civilian sectors, such as search and rescue operations, where accurate direction finding and target localization are critical. Full-duplex operation enhances the system's capability …

Measurement Automation & Measurement System Research Endowment, Brian Bivinetto, Beneda Loya, Shiron Bendrihem

College of Engineering Summer Undergraduate Research Program

Road travel safety is always the most important issue in transportation systems. In general, several factors cause road accidents, such as human error, vehicle mechanical failure, roadway limitations (e.g. pavement, lane geometry, etc.), and inclement weather conditions. The major focus of today’s transportation developments is related to making highway transportation safer, smarter, and greener to enhance livability. Many accidents are caused when drivers lack a better understanding of the surrounding traffic conditions because the driver not only needs to control his/her vehicle but also needs to be aware of the movements of the vehicles around him/her. A driver cannot be …

Sal-E: Responsive Space Pathfinder Mission, Liam Duckworth, Berfredd Quezon

College of Engineering Summer Undergraduate Research Program

The main objective of the SAL-E mission is to grow the Cal Poly CubeSat Lab’s (PolySat) capabilities in rapid spacecraft design, as well as to provide the current generation of students with the opportunity to design, test, integrate, and communicate with a satellite. This summer we will be focusing on a few aspects of the spacecraft design and preparing our test facilities for Fall. Specifically, we will be ordering electronics boards that were designed in Spring, testing the boards as they arrive, developing software to interface with the payloads, begin integrated testing, updating the control system in our thermal vacuum …

High-Power Microwave Antenna Design, Luke C. Chase

Electrical Engineering

High-power microwave antennas are essential for defense industry radar systems, cyber warfare, and power transmission. The US Department of Defense a SBIR proposal specifying the need for a high-power phased-array microwave antenna for the US Air Force.

Vivaldi antennas, invented in 1978 by Peter Gibson, have been widely adopted for radar applications due to their high bandwidth and gain performance. Considerable amounts of research exists on designing Vivaldis for different applications ranging from radar to communications. Using antenna theory and past research, a new Vivaldi antenna was designed to meet the requirements mandated by the DoD research contract.

This project …