# An Overview of CubeSat Missions and Applications
## 4 The Use of CubeSats as Telecommunication and Asset-Monitoring Platforms
### Radio Communication CubeSat Technologies  
The radio spectrum is usually defined as the part of the electromagnetic spectrum that covers the frequency range between 3 Hz and 300 GHz, with the electromagnetic waves of the radio spectrum being commonly defined as radio waves. Radio waves are used extensively in all telecommunication applications and by extension, in satellite communication since the beginning of space utilization and exploration. Similarly to their larger counterparts, to perform telecommunication operations, CubeSat platforms can be equipped with a variety of telecommunication-enabling systems. In terms of hardware, the most prominent example of these telecommunication systems are antennas, with a variety of different types such as low-gain monopole, dipole, and patch antennas being designed to be compatible in terms of size with the vast majority of CubeSat platforms. Furthermore, more complex and advanced designs such as inflatable and reflectarray medium-gain or high-gain antennas may also be utilized by large and/or highly specialized CubeSat platforms, such as the ones that undertake deep-space exploration missions. These antennas are coupled with transceivers or transponders providing the CubeSats with radio communication capabilities and commonly operate in the Very High Frequency (VHF), Ultra High Frequency (UHF), S-band, or X-band spectrums [130], with Ku-, Ka-, and W-band communications also being possible. In that regard, Figure 10 presents information about the communication frequencies used by past and present CubeSat missions where it is visible that UHF, S-band, and X-band communication frequency ranges represent the most popular choices. Table 4 presents the designations of radio frequency bands as specified by the Institute of Electrical and Electronics Engineers (IEEE) [131]. These radiofrequency bands cover the spectrum that is most commonly used by satellite communication systems. In general, the different communication systems found on satellites, based on their type and application, may operate in different radio frequencies and in a considerable number of cases, a single satellite may be equipped with two or more distinct communication systems that operate in different frequencies, each intended for distinct applications. The same is true for a variety of CubeSats who, despite their small size, may be equipped with an array of  
Figure 10: An overview of the communication frequencies utilized by CubeSat and other nanosatellite platforms as of the beginning of 2025. Data and illustration by Nanosats Database/Erik Kulu [17]. different communication systems. More detailed technical information regarding the antenna designs, communication systems, and frequencies utilized by CubeSat platforms can be found in [132]. Over the last 25 years, there have been a considerable number of examples of CubeSat missions that were dedicated to the in-orbit testing and demonstration of various communication hardware such as antennas and transceivers, as well as communication related software and new telecommunication concepts. One prominent example of such a demonstration mission was GomSpace Express-4 (GomX-4) which consisted of two 6U CubeSats, GomX-4A and GomX-4B, that were developed by GomSpace, the Danish Ministry of Defense and ESA. GomX-4A and GomX-4B were tasked with the demonstration of a variety of novel technologies which included multispectral imaging for Earth observation, but most importantly, the satellites successfully demonstrated the operation of hardware and software designed telecommunication applications such as S-band Inter-Satellite Link (ISL) communications, Automatic Identification Systems (AIS), and Automatic Dependent Surveillance-Broadcast (ADS-B) application hardware [133; 134]. Another prominent example of a successful telecommunication technology demonstration mission is the Integrated Solar Array and Reflectarray Antenna (ISARA) mission which was jointly developed by NASA's JPL and the Aerospace Corporation (Chantilly, VA, USA).