HIGH PERFORMANCES DATA HANDLING AND TRANSMISSION SYSTEMS: THE COSMO SECOND GENERATION SOLUTION

摘要

The Payload Data Handling and Transmission (PDHT) is a subsystem operating on board Earth observationsatellites to provide handling and transmission to Ground of the data acquired by high resolution radar instruments,typically Synthetic Aperture Radar (SAR).The really challenging needs, according to the requirements stated by ASI and I-MoD, of the COSMO SecondGeneration (CSG) mission, requires very high performances in terms of SAR acquisition data rates and data volumesper orbit, leading to a Payload Data Handling and Transmission (PDHT) architecture design completely new withrespect to the present flight proven solution.On the first generation of COSMO Sky-Med (CSK) satellites the SAR payload produces one data flow with amaximum rate of 600Mbps; on CSG the SAR is designed to simultaneously operate in dual polarization with anhigher resolution, providing to the PDHT two input data flows with an overall input data rate almost quadruple of theCSK one. Therefore, a significant improvement of the state of art PDHT storage capability and downlinkperformances are resulted necessary.The competitive mission needs together with the availability of good technology maturity level and theconsequent compatibility with the programme time schedule have driven the trade-off phase allowing theidentification of a new and high performance technological and architectural PDHT solution.The baseline PDHT solution has been identified; it is designed with a faster data acquisition interface and with anew modulation and coding scheme, the 4D-TCM 8PSK with Reed Solomon and interleaving, to enhance spectralefficiency and to allow increasing the downlink capabilities (higher than 500Mbps).Details on the PDHT baseline architecture for high performance real time data handling and transmission in theframe of Cosmo Second Generation mission will be provided highlighting the main features in terms of architecturaland technological aspects.