The Optical HighSpeed Infrared Link System (OSIRIS) is a technology demonstrator developed and built by the Institute of Communications and Navigation of DLR at Oberpfaffenhofen. Its goal is the demonstration of a cost-efficient optical downlink system with low technical complexity which can be used on future small satellite missions.

The instrument consists of two different optical transmitter units which are integrated into a single housing. Each unit is connected to an external collimator by fibre optics. The collimators will be mounted on the optical bench to ensure an ideal alignment with the payload cameras and the satellite's z-axis. The supply voltages needed by the transmitters are generated inside a separate box.

The two transmitters use different technologies. One is based on a high power laser diode while the other comprises a laser module and an erbium doped fibre amplifier (EDFA). Both transmitter units work at a wavelength of 1550 nm and use on-off-keying as modulation. OSIRIS has a maximum power consumption of 25 W and a mass of about 1.5 kg. The maximum transmission rate from orbit will be 80 Mbit/s.

The image below shows the OSIRIS FM.


The signals will be received by the Institute of Communications and Navigation in Oberpfaffenhofen through their Optical Ground Station of (OGS-OP, shown below) as well as their Transportable Optical Ground Station (TOGS).