Development of an experimental low-cost ground station for the small satellite project BIRD

Abstract

In the frame of the small satellite project BIRD, an Experimental Ground Station (EGS) is developed. The objectives of the EGS are: 1. Investigation and demonstration of direct user reception of regional data from earth observing satellites with a "low-cost" ground station 2. Analysis of autonomous activity capabilities, including high level image processing and alarm generation, such as new fire detection algorithms 3. Experimental tests for mission operations (commanding) The basic idea consist in the philosophy to give the user only regional limited data, for which a high performance ground station is not necessary. Thus the data volume to be received can be reduced. Many local authorities, such as agriculture or fire combat departments for example, needs only regional limited data to do a more efficient work in their region. The basic idea of the EGS is therefore, to analyze the capabilities and limits of a low-cost ground station, which outputs only the data, which is needed by the local end-user. The antenna size of such a Station can be small, which is one of the important cost drivers. The low-cost aspect of the system leads to a design, which incorporates the extensive use of existing commercial-of-the-shelf (COTS) hard- and software. A common PC with a Pentium class CPU is used for data reception and processing as well as for commanding. In order to have a compact size and a easy transportable system, most of the baseband hardware is built into the PC. The software for the downlink is intended to receive, display and store payload and housekeeping data. Payload data can be processed with a separate software, which uses algorithms developed by DLR. Special effort is made to implement fire detection algorithms. The housekeeping data can be displayed online, so that the health of the satellite can be monitored in real time or past data can be stored in order to analyze the satellite systems during no-contact times. The software for the uplink of telecommands allows also to send other data to the satellite, which can be used e.g. to update the on-board software or to support the classification algorithm. As for end of April 2000, most of the station hardware is in place and running. Some additions and modifications will be made in the Summer of 2000 in order to be ready for the launch of BIRD.