Realizing inter-satellite links is a must for ensuring the success of cubesat swarm missions. Nevertheless, it has hardly been considered until now. The communication systems for cubesats have to deal with a few peculiar demands regarding consumed power, geometry and throughput. Depending on the type of application, required data rates can go up to tens of megabits per second, while power consumption and physical size are limited by the platform. The proposed communication scheme will combine power-efficient modulation and channel coding with multiple access and spread spectrum techniques, enabling the deployment of multiple satellites. Apart from this, the antenna system has to be designed such that links can be established and maintained independent of the satellites' orientation. An electrically steerable radiation pattern is achieved by placing antennas on each face of the cube. Conformal beamforming provides the system with 5 dBi gain for any desired direction of transmission, eliminating the need for attitude control. Furthermore, using planar antennas reduces the complexity of the mechanical part as they require no deployment.

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Recent technological advancements have led to the emergence of a new miniaturized satellite platforms and this opened up the path for a whole new range of applications. The Orbiting Low Frequency Antennas for Radio Astronomy (OLFAR) project is one of these applications, and aims to develop a low-frequency radio telescope for the 0.3 MHz to 30 MHz band. It uses a swarm of 50 or more identical nano-satellites to synthesize a very large aperture to explore the ultra-long electromagnetic (EM) waves in this frequency band. The swarm will act similar to a wireless sensor network (WSN) that samples the cosmic noise, processes the data in a distributed manner, and then sends the data to a base station (BS) for further processing and analysis. The satellites will have a very simple architecture (characteristic of a WSN node) that will focus on three main functionalities: radio observation, data processing, and distribution (inter-satellite and downlink). However, the complexity of the application results in strict requirements for the design of the satellites components, especially for the antenna systems. Starting from OLFAR's requirements and limitations, three separate antenna systems for scientific observation, inter-satellite link (ISL) and data downlink are designed and integrated into a nano-satellite platform.

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