Date of Award


Degree Name

Master of Science in Engineering


Mechanical and Aerospace Engineering

First Advisor

Kristina Lemmer, Ph.D.

Second Advisor

Muralidhar Ghantasala, Ph.D.

Third Advisor

Michael McDonald, Ph.D.


ECR, microwave, plasma, propulsion, thruster

Access Setting

Masters Thesis-Open Access


Presented in this work is the process in the design and optimization of a coaxial electron cyclotron resonance thruster. Electron cyclotron resonance thrusters are novel microwave-based thrusters which possess select technological advantages over mature electric propulsion concepts such as being electrodeless and only requiring a single power source. The thruster constructed in this work is a coaxial configuration and is termed the Western electron cyclotron resonance thruster. Thruster dimensions were optimized based on past experimentation completed with ECR thrusters. In an attempt to enhance the microwave plasma coupling of the coaxial thruster design three different antenna configurations were considered: a monopole as used in previous studies, a ring antenna, and a helical antenna. Only the monopole and helical antenna went through experimental verification.

The characterization of the thruster was completed at Western Michigan University through a series of experiments and is presented here. These include the use of a variety of plasma diagnostic equipment consisting of a Langmuir probe, Faraday cup, and a retarding potential analyzer. The experiments allow the plasma properties and performance metrics such as thrust, specific impulse, and thruster efficiencies to be calculated. The thruster displayed performance on par with other first design iterations of electron cyclotron resonance thrusters; although, it did notreach the maximum performance obtained from more recent designs. From results obtained during experiments on the initial thruster design, a second thruster design was developed with select changes and improvements. Future investigations may include studies on microwave plasma coupling and magnetic nozzle physics. It is believed that electron cyclotron resonance thrusters possess the capability to play a significant role in the space industry and aid in its future development.