Compact UHF Antenna Utilizing CubeSat's Characteristic Modes

The paper investigates the use of CubeSat body as an UHF antenna for 435 MHz band. Since the lowest characteristic modes in 1U CubeSat become significant around 1 GHz, a set of four arms is developed to decrease this frequency and realize compact antenna that can be enclosed within in a sphere of 0.3 λ diameter. The antenna does not rely on any deployment mechanism, significantly increasing reliability of the satellite. Two use-cases are investigated: a linearly polarized with omnidirectional pattern and a bidirectional circularly polarized. Both offer broad beams with 1.6 dB gains, which is comparable to much larger deployable CubeSat antennas.