Analysis and Comparison of new Downlink Technologies for Earth Observation Satellites

• Main Authors: H. Henniger, S. Seyfarth, E. Diedrich
• Format: Article
• Language: English
• Published: Spolecnost pro radioelektronicke inzenyrstvi 2016-04-01
• Series: Radioengineering
• Subjects: Earth observation; downlink technologies; space mission design; space-to-ground link
• Online Access: http://www.radioeng.cz/fulltexts/2016/16_01_0001_0011.pdf

New generation of Earth observation sensors are creating an increasing amount of data which has to be delivered from space-to-ground. Additionally, many applications require timely availability of this sensor data. As new link technologies have been made available in the last years and data rate requirements are still increasing a revise of the conventional direct-downlink technology at X-band frequencies is essential. This work aims in a trade-off of the available direct-downlink technologies for satellites in low, polar orbits. Generally, there are two approaches to fulfill the requirement of timely delivery of a huge amount of data from space-to-ground. This is either increasing space-to-ground contact time resulting in a more complex ground station network or increasing carrier frequency whereas link reliability is limited by atmospheric effects. In this work different approaches like using K$_a$-band or utilizing ground station network with additional locations are compared against each other.