The objective is to design and develop a prototype remote interface and data handling unit for hosted payload instruments and SmallSat missions.

Miniaturisation of instrumentation for Space Weather (SWE) measurement systems is typically limited by the need to provide the interfaces to the spacecraft, in particular the power conditioning and voltage conversion. A flexible interfacing to the S/C bus and the isolation of potential failures within the instruments are necessary for the acceptance of payloads on-board of commercial hosting satellites in particular to realise flight opportunities with short notice. The activity shall develop a low-resource processing and interface unit that is optimised for space weather purposes and suitable for a variable set of instruments selected depending on the flight opportunity.

 

This activity shall develop a Payload Interface Data Handling Unit (PIDHU) for SWE hosted payloads which shall provide power supplies at various voltages required by space weather/environment instruments limiting the mass required for individual instrument voltage transformers. The PIDHU shall receive data streams from instruments through various protocols including UART (RS-422/485), SpaceWire, MIL-STD-1553 and CAN Bus and provide data though a single data interface adaptable to hosting spacecraft requirements. As an option, the PIDHU will include on-board data processing and storage capabilities to reduce the data bandwidth required and therefore increasing the volume of useable, processed data to be downlinked. As a further option, the system will include an interface to a dedicated transmitter allowing for independent downlink of data to a SSA or other ground stations. The design phase shall also consider the desired compatibility with a SmallSat mission which is currently under study.

The mass, volume and power requirement of such an PIDHU will depend strongly on the number of instruments to be supported, the ratio of the power conversion needed and the amount of on-board processing capability required. The baseline PIDHU to support more than 5 instruments and convert power from a 28 V (TBC) supply shall have a mass less than 2 kg and a volume envelope of less than 200 x 200 x 200 mm, which can be traded versus recurrent costs versus a modular building blocks approach. The power required by the instruments will be further investigated during the design phase of the study.

 

A proto-flight model of the PIDHU shall be built to conform to the requirements of an identified flight opportunity to test a selection of space weather/environment instruments presently under development. This proto-flight model shall undergo standard space environment tests and end-to-end qualification tests with the instruments identified as part of the payload.