Modeling and Measurement of Permittivity for Near Space Communications

Team NASAE, Not your Average Socially Awkward Engineers, is designing a circuit and package that can measure the permittivity of the air, as altitude changes, even near space, at 100 thousand feet.

Problem Statement
Our mission is to make new and exciting discoveries by designing, fabricating, and testing new devices to collect and analyze information about near space. The information to be measured is a quantity known as permittivity which describes a substance’s ability to resist an electric field. In order to measure permittivity in near space, aspects such as temperature, humidity, and signal frequency will need to be taken into consideration for accurate data collection. It is desirable to then plot this quantity with respect to time and position.

Mechanical Engineering Design Goals
Create a functional package (housing) for the electrical components to work and collect data properly. Model/Simulate forces, temperature, and other conditions on payload and package. Ensure that the payload will return to ground safely without affecting any of the packages inside. Find a material that will insulate our electric components to function at certain temperatures that will not interfere with data recording. Allows airflow to measurement devices. Allow component to work in different environments.

Electrical Engineering Design Goals
The goal of this project is to measure the permittivity of the air, from the ground to near space. We want to send a payload to near space, one hundred thousand kilometers, while measuring the permittivity as it goes up. At the very least, we will simulate this behavior using circuit design software. Permittivity: the ability of a substance to store electrical energy in an electric field. Basically, we want to measure the resistance of the air has to an electric field, or how long it takes for a charged particle to get from point A to point B. We will do this by measuring the capacitance of the air, as it goes higher into the atmosphere. Using equations that relate capacitance to permittivity, we will find what the permittivity of the air is, at certain points in the atmosphere.

Antenna Method
Using the Antenna method, we can calculate the permittivity by measuring how long it takes for the receiving antenna to capture the signal from the transmitting antenna.

The Package








Mechanical Analyses on the Package
Thermal Analysis Pictured to the right is a thermal analysis on the package that will be surrounding the circuit boards we create. This package will keep our electronics warm enough to operate during the flight. The circuit boards will be kept at about 20 °C, even at 100,000 feet.

Displacement Analysis Displacement Analysis of forces acting on top moving downward the box.

Strain Analysis Strain Analysis on Box as Forces Acting Downwards on top of the box.

Stress Analysis Stress Analysis on Box as Forces Acting Downwards on Top of the box.

Power Method
We will use a variant of the Friis equation, to find permittivity. We can do this by measuring the power transmitted, and the power received between two antennas.

Capacitor Method
Measure the capacitance of a parallel plate capacitor then use the equation, C = ε 𝐴/𝑑, to solve for the permittivity. Viable up to roughly 1 Ghz

Laser/Phase Velocity Method
Measure the phase velocity of a signal and use the equation, vp = 𝑐/sqrt(μ𝑠*ε𝑠), assuming μs is 1.

Boundary Condition Method
Using the relationship between a conductor and a dielectric we can find the electric field in free space and the surface charge of the conductor to calculate ε using the equation, ρs = ε Et.

Benjamin VanSant
Mechanical Engineering Student

Hometown: Stanwood, WA

Hobbies and Interests: I love being outdoors and being active. Soccer, rock climbing, mountain biking, and snowboarding are a few of my favorite activities. I am interested in motorsports and racing. Someday I would love to find a job in that field, designing (or driving) high end cars or motorcycles.

Future Plans: Next year I will be entering the workforce. I am planning to move to either the Puget Sound area or southern California to find a design or manufacturing job which will give me the opportunity to grow as an engineer.

Email: vans6909@vandals.uidaho.edu



Brett Morris
Mechanical Engineering Student

Hometown: Oakley, CA

Hobbies/Interests: I am interested in how things work in mechanical systems and how they are designed. I always thought it was fascinating how people created 2D objects and transformed them into 3D models using CAD and other programs. Some of my hobbies are; snowboarding, video games, hanging out with family/friends, and sports.

Plan for Future: Pass the Fundamental Engineering exam as soon as possible and then start working towards passing the Professional Engineering exam. I would like to live and work in the Pacific Northwest.

Email: morr7547@vandals.uidaho.edu



Cameron Murdock
Electrical Engineering Student

Hometown: Laclede, ID

Hobbies/Interests: In general, my interests involve understanding how various systems work and how to improve those systems. In the field of Electrical Engineering, my interests include signal analysis and control theory. In my free time, I enjoy learning about new technologies and exploring the outdoors.

Plan for Future: As of now, I am not set on a particular path. I may go on to graduate school at Montana State University in order to study photonics so that I can eventually work at Bridger Photonics which is a company where I was an intern over the Summer of 2016.

Email: murd7115@vandals.uidaho.edu



Jeffrey Craig
Electrical Engineering Student

Hometown: Enumclaw, WA

Hobbies and interests: I am interested in technology in general. I like to build models, draw, and play videogames. It is fascinating how fast technology is growing, take the Nintendo Switch for example, it is so innovative. I have been involved with many engineering related clubs on campus, including IEEE, IMAPS, and ECE Ambassadors. Working on electrical projects on the side is also pastime of mine, I recently build a board that lights up with LEDs.

Plan for the future: After graduation I would like to work in the Seattle area. I have worked for the same company the past two summers, and would like to work for them again, in the avionics industry. It would be fun to eventually end up working for Nintendo though.

Email: crai5936@vandals.uidaho.edu



Ryan May
Electrical Engineering Student

Hometown: Boise, ID

Hobbies and interests: I am interested in communication systems as far as electrical engineering goes, I am also interested in science in general. Since my freshman year I have been involved in a research lab in the biology department investigating how transmissible vaccines could improve how we combat viruses in both epidemic and endemic situations through mathematical models. My hobbies include video games, mountain biking, and skiing.

Plan for the future: After graduating I do not plan to pursue a career involving communication, ideally working either with satellite communication or radar with ships and submarines.

Email: may6552@vandals.uidaho.edu