Carl L. Kobza

Date of Award


Document Type


Degree Name

Master of Science in Space Systems


Department of Aeronautics and Astronautics

First Advisor

Richard Cobb, PhD.


Increasingly capable CubeSat missions require antenna with improved Radio Frequency performance over the traditional CubeSat antennas. Deployable quadrifilar helical antennas (QHA) enable an acceptable stowing volume and deploy to provide increased gain and bandwidth over traditional patch and dipole antennas. Extensive ground testing is required to ensure the antenna is space qualified and to characterize the antenna deployment in the space environment. AFIT requires a QHA to perform a future CubeSat geolocation mission and contracted Helical Communication Technologies (HCT) to design and manufacture a Shape Memory Alloy (SMA) L-band deployable QHA. Vibration, thermal vacuum, laser vibrometer, and Voltage Standing Wave Ratio (VSWR) experiments were conducted on the HCT antenna to verify the hardware in a simulated launch environment and to characterize the SMA deployment in the simulated space environment.The HCT QHA successfully passed all required NASA General Environmental Verification Standards space qualification testing. Several anomalies experienced by the QHA encourage a redesign. The deployed antenna length varied from 250-290 mm and future RF testing is required to determine if the antenna geometry variations are significant enough to impact the geolocation mission.This research documents the test results for a QHA deployable CubeSat antenna testing and aids the development of CONOPS for the future AFIT CubeSat mission utilizing the HCT QHAs.

AFIT Designator


DTIC Accession Number