1. Operational deployment of GPS Dancer: organisation, status and schedule Henno Boomkamp Jerôme Verstrynge, Jeff Daniels, Claus Randolph, Veronique Séjan, et al. For list of all project volunteers please see GPSdancer.org  Project  Credits IAG REFAG 2014 Luxembourg 13-17 October

2. GPS Dancer IN A NUTSHELL (1) 2 current situation REFAG 2014 Luxembourg Global network solutions (IGS) limited to ~250 stations each Result: layered densification to user level –Too few stations included at NEQ level (…only EUREF, AFREF, SIGRAS etc) –Each layer adds errors, latency, cost, regulations, … High accuracy of ITRF fails to reach regional sites & users 2.8 mm RMS RTK, DGPS

3. GPS Dancer IN A NUTSHELL (2) 3REFAG 2014 Luxembourg Rigorous LSQ solutions for all permanent GPS sites in the world Pile of computations is too large for one computer  …split in many piles –Price to pay is data traffic and some repeated, parallel computations Most sites do not publish their data  …bring the process to the site ?!? … … ……

4. GPS Dancer IN A NUTSHELL (3) 4 dancer approach REFAG 2014 Luxembourg IGS-like solutions via a peer-to-peer internet process –Workload for one peer process per receiver: ~0.5 x IGS AC –Data traffic grows as a logarithmic function of network size N –Observations and local products remain private to the receiver! High accuracy can reach regional sites and users 2.8 mm RMS RTK, DGPS

5. GPS Dancer project timeline REFAG 2014 Luxembourg5 analysis software implementation organization fundraising operations web presence key meetings now releases

6. Roadmap towards operational system REFAG 2014 Luxembourg6 Step 1: Deployment Build up backbone network for ~100 ITRF sites Test runs on basis of one week of RINEX files Near real-time runs in parallel to IGS Step 1: Deployment Build up backbone network for ~100 ITRF sites Test runs on basis of one week of RINEX files Near real-time runs in parallel to IGS Step 2: Calibration / Validation Routine comparisons against IGS products Tune all models and standards to IGS repro-2 standard Step 2: Calibration / Validation Routine comparisons against IGS products Tune all models and standards to IGS repro-2 standard Step 3: Pilot project Users can join with their own stations Alignment to ITRF via backbone network No guarantee of service Step 3: Pilot project Users can join with their own stations Alignment to ITRF via backbone network No guarantee of service Step 4: Nominal operations Global products made available to IGS (if desired) Limited guarantee of service to users (e.g. 99% of time) Step 4: Nominal operations Global products made available to IGS (if desired) Limited guarantee of service to users (e.g. 99% of time) 24 arc length Low data rate (5 min) Low product rate (6 hrs) 18 hour arc overlaps 24 arc length High data rate (30 sec) High product rate (0.5 hrs) 23.5 hour arc overlaps

7. Computing resources: options considered Plan A: use the station computers –but: modern receivers stream data directly –inhomogeneous performance & bandwidth Plan B: voluntary analysis campaign –but: unreasonable processing load –100 peers equivalent to ~50 analysis centers Plan C: cloud computing –unlimited capacity @ low cost to user –highly homogeneous hardware & network –no charge for incoming data or internal data Funding needed for backbone networks 7 200 MB internal 100 kB out 1 MB in REFAG 2014 Luxembourg

8. Dancer in the cloud = smart receiver! 8 Today Smart receiver 1 Smart Receiver 2 Smart receiver 3 Dancer in the cloud Hardware Software GNSS observations (RINEX, RTCM) GNSS products HF signals expensive new hardware cheap new hardware existing hardware REFAG 2014 Luxembourg GNSS products

9. Backbone network budget Required start-up budget –Step 1: deployment E2C …........~20 k –Step 2: CalVal / ITRF low rate …~30 k –Step 3: Pilot project ……………..~50 k  Total ~100 k DART development by means of EU H2020 project REFAG 2014 Luxembourg9 1000 sites (>100 ITRF) 100 ITRF sites 250 ITRF sites

10. Funding options and their pitfalls public funding (ESA) single private investor many private investors REFAG 2014 Luxembourg Full funding imposes political constraints Development only: ESA is no service operator Scientific control is lost Difficult to involve other manufacturers Weak governance Available public funding is not exploited Reference frame should not be commercialized, scientific supervision (IAG, IGS) is important Option A Option B Option C 10

11. GPS Dancer operational organization REFAG 2014 Luxembourg 11 (1) Global Geodetic Grid Foundation Governance: 5 (or 7) representatives from the scientific community Assets: IPR of the GPS Dancer software (…released via Apache 2 license) Run time start-up passwords IPR global estimation products orbits, satellite clocks, ERP 50% of the GCCS (3) Users of the service Assets: IPR of GNSS observation data IPR local estimation products position, station clocks, tropo (2) Geodetic Cloud Computing Service Governance: 50% GGGF (…board votes as one) Proportional vote by shareholders 50% “virtual vote” for each co-funder ! GGGFGGGF Start-up funding Operational ownership Smart Receiver Manufacturers

12. Fundraising status Oct 2014 REFAG 2014 Luxembourg12 First choice: receiver manufacturers (…have been / will be contacted) Second choice: GNSS / geodesy SME Known contacts via IGS / IAG ESA contractor firms …etc. Third choice: any private investor Yes Maybe No …yet to be contacted Yes Start of fundraisingMay 2014 Decision deadline Jan 2015 Target # for go-ahead 8 … 10 Start of fundraisingMay 2014 Decision deadline Jan 2015 Target # for go-ahead 8 … 10 *

13. Dart implementation Schedule 2015 ESA BIC Evaluation Board  Feb 2015 –Dancer moves from IAG voluntary project to paid service –Not aimed at profit, but cost must be carried by the users IAG 2013 Postdam13 GGGF v1 GGGF v2 GCCS GmbH Week 7: TEB Step 1: deployment Step 2: CalVal Week 25 AGU 2015 / IGS 2016 Step 3: Pilot project ICDs with manufacturers Certification of cloud service

14. Conclusions Dancer wants to bridge the accuracy gap from ITRF core to all regional sites, and then to the user Progress 2014 –Operational organization developed in detail Cloud service (GCCS) under scientific supervision (GGGF) Realistic funding devised and being consolidated Target for start of public pilot project is now AGU 2015 DART (Dancer-RT) project now also under preparation –Aiming for a H2020 project over 2016-2018 period 2018: 2.8 mm ITRF anywhere on Earth, in real time? IAG 2013 Postdam14

15. …why do we need GPS Dancer? IAG 2013 Postdam 15 All regional sites at high ITRF accuracy Guarantee of service W1 N W2 street level pseudolites roof top GPS base station local offset surveyed Densifications to 1 km or less