Cubesat Broadcasting: Feasibility and Considerations

As part of a research project involving a constellation of seven Cubesats, we are exploring the possibility of broadcasting using these small satellites. While Cubesats offer incredible potential for various applications, their size and limitations pose challenges when it comes to broadcasting. In this article, we will delve into the feasibility of broadcasting with Cubesats, explore the underlying considerations, and discuss the necessary factors to achieve this goal.

Introduction to Cubesats and Broadcasting

Cubesats, also known as CubeSats, are nanosatellites that measure approximately 10 cm x 10 cm x 10 cm, and have revolutionized space research and technology. They are often used for educational purposes, testing new technologies, and for providing a platform for various experimental payloads. However, when it comes to broadcasting, the limitations become evident due to their size and power constraints.

Understanding the Challenge

The question often arises whether Cubesats can perform broadcasting. It is important to clarify the term: broadcasting usually refers to transmitting information to a broad region continuously. Traditional broadcasting is typically associated with geosynchronous satellites, which are large and powerful enough to cover vast areas. In contrast, Cubesats in low Earth orbit (LEO) are moving too quickly to maintain continuous coverage of a fixed region.

Current Capabilities of Cubesats

Cubesats can transmit information to ground stations using their onboard communication systems. However, these transmissions are limited by the satellite’s power output. A Cubesat’s radio system requires significant power, and due to its small size, it has limited capability to generate such power. Therefore, the transmission power of Cubesats is often insufficient for conventional broadcasting.

Moreover, a single Cubesat in LEO is moving so fast that its coverage of the Earth’s surface is limited. This means that a Cubesat would not be an effective solution for broadcasting over a wide geographical area. However, the concept of a constellation of many smaller Cubesats working together could theoretically provide a broad coverage area, similar to that of a network of geosynchronous satellites.

Unintended Broadcasting

It is worth noting that Cubesats do not necessarily need to broadcast in the traditional sense. Due to their small size and the use of omnidirectional antennas, Cubesats actually emit a wide signal, essentially broadcasting to a region around them. This can be advantageous in certain scenarios, such as emergency situations where the satellite loses control and cannot point its antenna correctly. An omnidirectional antenna allows the signal to be detected from any direction, which increases the chances of recovery.

Power and Antenna Considerations

The effectiveness of a Cubesat’s broadcasting capability depends heavily on the power available for the radio system and the size of the receiving and transmitting antennas. Traditional broadcasting relies on large antennas and powerful amplifiers to achieve the necessary signal strength. In contrast, Cubesats have limited power and very small antennas, which means their signal will be weaker and more dispersed.

One critical factor is the electrical power available for the radio. Cubesats are small and have limited power sources, typically solar panels. The radio signals transmitted by Cubesats are therefore not as powerful as those from larger satellites. Additionally, the Earth's curvature means that receivers below the satellite are closer, further diminishing the signal strength for side receivers.

Another crucial element is the design of the antenna and its frequency. While these are indeed challenging aspects, they play a significant role in determining the overall effectiveness of transmission.

Conclusion

While Cubesats may not be ideal for traditional broadcasting, they can still perform a form of broadcasting through their omnidirectional antennas and wide signal distribution. The feasibility of broadcasting with Cubesats depends on the size of the receiving and transmitting antennas, the available power, and other design factors.

We believe that our exploration into utilizing Cubesats for broadcasting could pave the way for innovative applications in media art installations and other interdisciplinary projects. By overcoming the challenges and leveraging the unique capabilities of Cubesats, we can push the boundaries of what is possible in small satellite communication.