Jérôme Lafeuille WMO Space Programme Direct Broadcast Network (DBNet) for Near Real-Time Relay of LEO Satellite Data (From RARS to DBNet) Jérôme Lafeuille WMO Space Programme

Talking points From RARS to DBNet Outline of DBNet WG I question on X-Band transmission polarization Annex: RARS status CGMS-43, May 2015

WMO and ITWG Discussions on RARS evolution 2012: RARS Implementation Group & ITSC-18 RARS sub-group: Addressed extension of RARS to hyperspectral sounders and FY-3 sensors Coding, data volumes and dissemination issues for these new sensors April 2014: RARS Technical Subgroup at ITSC-19 (Jeju) actions SSEC, NOAA, EUMETSAT, WMO should coordinate on data formats, software versions, and latency requirements and come up with a plan to provide the DBRTN products for inclusion in RARS The draft Guide on RARS defining the RARS procedures, software, formats, data exchange convention, service requirements, etc. should be finalized, published, and shared widely with potential data providers The RARS Implementation Group within WMO should be reactivated with a broader scope to include NOAA DBRTN Sept. 2014: CBS Ext welcomed “DRARS” and drafting a Guide to DRARS CGMS-43, May 2015

CGMS Discussions on RARS evolution CGMS-41 (Tsukuba, July 2013) NOAA announces DBRTN initiative to establish a network of NPP (X-band) receiving stations and associated processing to provide short timeliness sounding products for NWP A41.54: NOAA and WMO to discuss the relation of the Direct Broadcast Data Initiative to RARS, and how RARS can take advantage of this initiative Nomination of a RARS Task Team CGMS-42 (Guangzhou, May 2014) R42.11: CGMS Satellite operators to support the definition and implementation of community agreed operational procedures for LEO satellite data direct read-out, acquisition, and relay in the context of the DRARS Implementation Group. R42.03 , R42.04, R42.06: are addressing software and acquisition aspects CGMS-43, May 2015

From RARS to DBNet Coordination meeting in Geneva, 11-13 March 2015 Participation: RARS Asia-Pacific (KMA, IMD, JMA, BoM, CMA, Meteo-France) RARS South America (SMN Argentina) RARS Europe/EARS (EUMETSAT) RARS central monitoring unit (EUMETSAT NWPSAF) NOAA DBRTN project WMO Secretariat (SAT, WIS) Chaired by Anthony Rea (BOM, Asia-Pacific RARS coordinator) Reviewed status of RARS, outstanding issue, NOAA DBRTN initiative Considered high-level specifications for new services (NPP, Metop, JPSS, FY-3) can evolve with user needs, potential addition of other sensors Areas of harmonization/standardization required to support new services Agreed to rebrand the overall initiative as “DBNet” CGMS-43, May 2015

Talking points From RARS to DBNet Outline of DBNet WG I question on X-Band transmission polarization Annex: RARS status CGMS-43, May 2015

Towards a Guide on DBNet A Guide to DBNet is being developed to record the DBNet specifications, standard practices, and coordination mechanisms Prompts useful discussions on the best practices to be adopted Draft to be presented to APSDEU-NAEDEX and ITSC-20 (Oct 2015) Will serve as reference for implementing the DBNet services It should be a living document. Sections on future services can be added or refined later First version submitted to WMO CBS (2016) CGMS-43, May 2015

Regional or Sub-regional Node DBNet Components DBNet is composed of regional networks coordinated by regional or sub-regional nodes and a global DBNet Coordination Group Global monitoring of product consistency is performed by the NWPSAF Regional Network Regional or Sub-regional Node DBNet - Europe  EUMETSAT DBNet - Asia-Pacific JMA BoM DBNet - South America INPE SMN Argentina DBNet - North America  NOAA CGMS-43, May 2015

High-level Service Specifications Products, Timeliness, Availability, Coverage Established with user bodies (ITWG, APSDEU-NAEDEX, IPET-SUP) Timeliness: 15 min rather than 30 min Coverage: requirement at the network level, trade-off with cost CGMS-43, May 2015

Current and potential DBNet services Each DBNet regional network contributes to one or more “Services”. A DBNet Service consists of Direct Broadcast acquisition, processing and relay of a certain category of satellite data RARS (ATOVS) will remain, as one of the DBNet Services Categories of services Services/Instruments IR/MW sounding             RARS (AMSU-A, MHS, HIRS) ATMS, VASS (MWTS, MWHS, IRAS) Hyperspectral IR sounding           CrIS, IASI, HIRAS IR/VIS imaging                  VIIRS, AVHRR, MERSI Scatterometry ASCAT MW imagery MWRI CGMS-43, May 2015

DBNet Areas of harmonisation/standardisation DBNet Network Management Operational monitoring Implementation planning User information Common DBNet Standards and Recommended Practices Acquisition Product Processing (AAPP, CSPP etc.) Product Coding, Format and Distribution DBNet Product Registration and Discovery Specific Standards for Groups of DBNet Services IR/MW sounding IR/VIS imaging service High Resolution Sounding Scatterometry CGMS-43, May 2015

Common processing software suite and orbital elements for product consistency CGMS-43, May 2015

DBNet (potential coverage) Current RARS network (ATOVS) Potential RARS Africa (ACMAD) New NOAA sites (Seaspace NPP) CGMS-43, May 2015

DBNet Implementation (1) DBNet Guide will define the agreed specifications and practices DBNet Coordination Group is established within WMO SP to support the development and implementation of DBNet DBNet Coordination Group Terms of Reference include: Keep under review the specifications of DBNet services in consultation with users Coordinate the implementation/expansion of DBNet networks & services Define/maintain standards ensuring interoperability and inter-regional exchange of DBNet products, in consistency with WIS Monitor the performance of DBNet components and take appropriate actions Keep under review the priorities for filling coverage gaps, acquisition scheduling Identify issues to be submitted for consideration by CGMS satellite operators CGMS-43, May 2015

DBNet Implementation (2) DBNet Coordination Group Shall be composed of network coordinators, providers of L0/L1 processing software, technical experts designated by the contributing organizations, and WMO Secretariat should meet annually and hold virtual meetings would report to WMO CBS (via the OPAG ISS) should provide annual report to CGMS CGMS-43, May 2015

DBNet Initial technical actions NOAA and EUMETSAT will collaborate to integrate the NOAA DBRTN project as a component of DBNet Improve availability of RARS products Timeliness issue for some stations Reception scheduling to give higher priority to NOAA-18 than NOAA-15 (given the shift of Equator Crossing Time) Compatibility of RARS and DBRTN BUFR products for IASI and CrIS CGMS Task Team on Metadata to define discovery MD for DBNet Operators to complete registration of DBNet products with WIS Analyse with APSDEU-NAEDEX (Oct. 2015) the request for data exchange through WIS (originating centers, NWP users, data profile, volume and timeliness) CGMS-43, May 2015

Talking points From RARS to DBNet Outline of DBNet WG I question on X-Band transmission polarization Annex: RARS status CGMS-43, May 2015

X-Band transmission polarization issue (1/3) There is a risk of interference in X-Band as meteorological satellites use the same frequency range and (so far) same (RHCP) polarization To mitigate this risk, CMA uses LHCP on FY-3C and announced the intention to use LHCP on every other future spacecraft of FY-3 series CGMS-WG I requested feedback from RARS about possible use of LHCP instead of RHCP for X-Band Direct Broadcast (e.g. for FY-3) CGMS-43, May 2015

X-Band transmission polarization issue (2/3) Comment by DBNet group The risk of interference is in case of simultaneous overpass FY-3E,-3G, candidates for LHCP, are assumed in early morning The other satellites, using RHCP, are in am or pm orbits Simultaneous overpass between em and am/pm can only occur at very high latitude (~80°) If all were using RHCP there would be an additional risk of interference, however limited to very high latitudes If they use different polarizations, users worldwide would not be able to receive all satellites on the same antenna, unless the polarization is made configurable on the receiving system This issue would be critical with FY-3E , which is planned to transmit all data in X-Band only, tentatively in LHCP. CGMS-43, May 2015

X-Band transmission polarization issue (3/3) Conclusion To evaluate the impact on user side, all station operators should be asked the type of receiving station they are operating and should investigate the feasibility of making the polarization configurable (LHCP/RHCP) to be able to acquire future FY-3 E/G DB The RARS regional/subregional coordinators should send enquiries Responses could be compiled by WMO  As a rule, satellite operators should provide details on DB services several years in advance of new systems, including for instance frequency, polarization, encoding, G/T requirements, conformance with CCSDS. CGMS-43, May 2015

General Conclusions RARS is successfully receiving, processing and distributing ATOVS data covering 80% of the Earth surface DBNet provides a framework for adding services based on new sensors (IASI, CrIS, ATMS, VIIRS, MWTS, MWHS, IRAS, HIRAS,…) and integrating the NOAA DBRTN initiative The DBNet coordination group will drive forward the DBNet implementation and consolidate the existing ATOVS services The Guide to DBNet will provide visibility by the user community and enable formal recognition by WMO/CBS Excellent model of collaborative undertaking by satellite operators and user groups, fostered by CGMS and WMO CGMS-43, May 2015

Future actions for CGMS Satellite operators and their partners are playing a crucial role to provide and maintain processing software such as AAPP, CSPP, FY3PP which are core building blocks of DBNet Integration into WIS through data/metadata registration and common format implementation are other key elements for interoperability and wide user uptake DB Net may express recommendations to satellite operators as regards standardization of DB services CGMS WG I members – (former RARS task team) invited to actively contribute to finalizing the Guide to DBNet in view of adoption by CGMS-44/WG I before submission to CBS CGMS-43, May 2015

Thank you! CGMS-43, May 2015

Talking points From RARS to DBNet Outline of DBNet WG I question on X-Band transmission polarization Annex: RARS status (information) CGMS-43, May 2015

Initial WMO RARS concept and objective Global availability of near real-time ATOVS data received by a collection of Direct Broadcast stations distributed around the world Ensuring global consistency by using common software (AAPP), standardized coding and file naming, and quality monitoring Dissemination by the WMO GTS or otherwise (e.g. satellite broadcast) Initial goal: NOAA and Metop ATOVS (L1b) from 90% of the globe available on the GTS in 30 min ATOVS= HIRS, AMSU-A, AMSU-B, MHS CGMS-43, May 2015

RARS/ATOVS implementation status http://www.wmo.int/pages/prog/sat/rars_en.php Regional components January 2009 March 2014 March 2015 (TBC) EARS 10 stations 23% 15 stations 40% Asia-Pacific 14 stations 28% 15 stations 29% 17 stations 33% South-America 5 stations 10% 8 stations 14% 7 stations 13 % Overall network 29 stations 61% 38 stations 75% 39 stations 80% The percentages are the fraction of the globe (except polar caps) above which the DB signal emitted by a SSO satellite is received by at least one station of the RARS network CGMS-43, May 2015

Typical Timeliness monitored in Tokyo (JMA) http://ds. data. jma. go Overall latency between start of reception and availability in Tokyo through the GTS is of the order of 15-20 minutes in most cases for Asia-Pacific RARS/ATOVS data Receiving Processing Transferring CGMS-43, May 2015