An advanced research environment for Ka-band satellite communications

The Institute of Astronautics (IA, Lehrstuhl Raumfahrttechnik / LRT) at Technische Universität München has a strong background in inter-satellite communication. The efforts were driven by the need of developing key methods and hardware for controlling robotic space applications by a user on ground. In this framework, research was conducted to control robotic applications on Earth via a geostationary relay satellite. Extensive tests showed that high bandwidth is necessary to fulfill the high performance requirements on a communication link for robotic systems featuring haptic and visual feedback. Thus, a Ka-band ground station and a Ka-band satellite mock-up system was set up at the LRT. The antenna system was developed with a special measurement configuration to meet the requirement of a high flexibility degree for measurements. To guarantee high precision measurements, the ground station is equipped with an inject-pilot system in the reception. The high precision coupler and power meter in the transmission path allow a well adjustable uplink power to the satellite. The performance of the ground station was verified with an extended ESVA (Earth Station Verification & Acceptance) test together with EUTELSAT and ESA (European Space Agency). The whole antenna system was calibrated with a high precision Standard-Gain-Horn to increase the measurement performance. This paper describes ongoing activities at the LRT, focusing the Ka-band ground station and the Ka-band satellite mock-up system. It further outlines the possibilities that arise from using a Ka-band environment (ground station and mock-up) that can be easily accessed and used by research partners, since the ground station and the mock-up are not dedicated to one satellite operator only.