Data Collection Platforms
The collection and distribution of environmental data from Data Collection Platforms (DCP) is one of the core services for many meteorological satellites around the globe. DCP stations transmit data from various meteorological and environmental sensors in the UHF band (Ultra High Frequency) via satellites. Depending on the Data Collection System, the DCP band is subdivided into several hundred DCP channels.
Since 2002 SCISYS provide Software Defined Radio Receivers for DCP Reception Systems used in North and South America as well as in Europe.
In February 2018, SCISYS finished the development of the new Data Collection Platform Facility (DCP-F) on behalf of EUMETSAT. DCP-F is the new multi-mission component for GEO missions supporting the acquisition, processing and dissemination of messages transmitted by the DCP platforms and relayed by GEO satellites in support of the CGMS DCS mission.
Within an ESA project, SCISYS developed a reference DCP Transmitter supporting all DCP missions for GOES and METEOSAT SRDCP and HRDCP. The HRDCP transmitter has been certified by EUMETSAT as part of the project. The second major achievement of the project was the preliminary definition of a potential DCP New Air Interface, the Enhanced DCP.
DCP-F is the new multi-mission component for the EUMETSAT GEO missions supporting the acquisition, processing and dissemination of messages transmitted by the DCP platforms and relayed by METEOSAT in support of the CGMS DCS mission. In preparation for the METEOSAT Third Generation, this involvement included the design, development and test of a new MTG DCP receiver as well as the digital simulation of up to 700 parallel MTG DCP messages at radio frequency level. The design and definition of the target platform for the operational and validation systems of the DCP Facility and the integration, testing and verification including all existing DCP-F subsystems like the Processing element and the MTG DCP receivers is also part of our contribution.
HRDCP certified TX for EUMETSAT
Within an ESA ARTES 5.1 technology program project, SCISYS developed a reference DCP Transmitter supporting the legacy DCP missions of the GOES 300/1200 Baud, the international 100 Baud SRDCP as well as EUMETSAT’s 1200 Baud HRDCP specification.
The developed prototype is market competitive at all points, performance-, production costs- and manageability-wise. Furthermore, it is certified by EUMETSAT for Meteosat HRDCP operation. TRL6 is reached for HRDCP and TRL5 for all other missions including EDCP (Enhanced DCP). Design challenges like high frequency stability and low phase noise of the UHF carrier versus low power operation over a wide supply voltage and operating temperature range have been mastered. Only a few small modifications of the prototype design will be necessary to meet all the target specifications established at the beginning of the project.
The DCP market is dominated by US companies. There is no European supplier of DCP transmitters. The DCP-Tx design can serve as a basis for European companies interested in the DCP market.
Beside this the new generation radio interface specification could support the definition of a new international DCP standard closing the bridge between the different DCP specifications used by the different satellite operators.
The DCP transmitter shall autonomously work under harsh environmental conditions. Due to this and due to the DCP standards, a number of design drivers have been identified such as
- very high frequency stability and low phase noise
- requirements for very low standby power consumption
- wide operating temperature and self-heating during transmit operation
- likelihood of periods without GPS reception in certain environments (forest, etc.)
Furthermore, SCISYS aimed for a common DCP-Tx HW platform supporting the legacy DCP and the new generation air interface. This approach could not be confirmed unless the baseline specification of the new generation air interface was decided. Accordingly, the HW and FW design have to support Software Defined Radio to be flexible.
The DCP-Tx system features are intended to be competitive with other DCP transmitters from the US. Beside the TRL Level 5, the current design has reached the EUMETSAT certification (No 2018-004-DCP-HDR). In addition, the same HW supports the proposed new generation air interface standard up to prototype level. The DCP-Tx is ready to allow EDCP tests via the METEOSAT satellite.
EDCP proposal for future work/enhancements
The second major achievement of the ESA ARTES 5.1 technology program project was the preliminary definition of a potential DCP New Air Interface. EDCP stands for “Enhanced Data Collection Platform” and was so named as a proposed enhancement to the existing options supported by EUMETSAT and potentially by other DCP operators world-wide.
The goals for the “new air interface” were very broadly defined at the start and during the project we solicited responses from many people, companies, and organizations with an interest in the use and future of the DCP system. From this we analysed the desired performance goals and proposed two EDCP variations, targeting mainly movement tolerance and data integrity while maintaining transponder compatibility and still fitting into existing Meteosat and GOES channel slots.
Both EDCP alternatives, BPSK and Pi/2-BPSK were implemented in the transmitter prototype hardware and proven to work together with the extended 2met! DCP Acquisition software in laboratory tests.
In addition, simulations of the complete TX-RX chain in view to Gaussian noise, FM/AM effects and sweeping/fixed CW interference clearly showed the EDCP phase noise robustness advantages, especially compared to the older SRDCP and GOES standards.