ÁREA DE GEODESIA

Current status of the National GNSS Permanent Stations Network (ERGNSS)E. Azcue Infanzón, S. Calvo Ferruelo, P. Gonzalo López, J. A. Sánchez Sobrino, M. Valdés Pérez de Vargas

Área de Geodesia – Subdirección General de Geodesia y Cartografía – Instituto Geográfico Nacional

1. Introduction

In 1998 IGN-E started to install the National GNSS Permanent StationsNetwork, with the first station installed in the tide gauge of Alicante, verticaldatum for the Spanish Height System. This station was the first integratedin the EUREF Permanent Network, EPN (ALAC).

Later, new stations were installed mainly in other observatories and tidegauges, like YEBE, co-located next to the former 14 m VLBI antenna of theYebes Observatory. Main objectives of the network were:

To contribute to the realizations of ITRF and ETRS89 in Spain.To provide public data for users of cartography, civil engineering,navigation, earth sciences investigation, etc.To constitute an active network which provide access to ETRS89through real time positioning.

Currently, ERGNSS network is formed by 72 stations whose:24 EPN stations.

3 IGS stations.

13 in the ITRF realization.

68 GPS + GLONASS.

29 individual calibration antennas.

Through agreements with Autonomous Region networks, some stations that fullfil the necessaryrequirements are being integrated in the national network ERGNSS. The completed network willconsist of about 92 stations.

Most of them are being connected with the Spanish High Precision Levelling Network and others withthe absolute gravimetric network.

Data of the network in the IGN EUREF Local Data Center: ftp://ftp.geodesia.ign.es

2. Current status of ERGNSS

EUREF-IP caster provides single point RTK solution from all stations from2002.

A new service of real time positioning network-based solution has beenimplemented in collaboration with Autonomous Regions networks.

Service available in Peninsula and Balearic Islands with about 210 stationsparticipating in the solutions. In the near future the system will beimplemented in Canary Islands.

Running over GNSMART (Geo++) the stations are divided geographicallyin 17 clusters with overlaping and 7 servers processing.

The service provides VRS, MAC, FKP and single point solutions to theusers, all with GPS or GPS+GLONASS.

Precision tests carried out in several areas along the country fulfill theexpected accuracy of RTK service (1-2 cm in planimetric and better than 3-4 cm in altimetry).

3. Real time services

4. Proccessing GNSS data at IGN-E

Current status of ERGNSS network.

SUBDIRECCIÓN GENERAL DE GEODESIA Y CARTOGRAFÍA

EUREF LAC: weekly proccessing since 2001, currently 75 stations subnetwork,BSW5.2.

Repro2: 125 EPN stations analyzed from 1994 to 2014 in the west area of Europe.

Dense velocity field project: Iberian Network (IBERRED) with geodynamicpurposes. Including stations of IGN, Autonomous Region networks, privatecompanies, Portugal (IGP), south of France (IGN-F) and other public institutions.As a result of this process IGN is also making time series analysis of thecoordinates for monitoring and geodynamical studies of about 350 stations,collaborating at the same time with the “Regional Dense Velocitiy Field” Projectmanaged by the same called IAG Working Group.

E-GVAP: Zenith Troposphere Delay (ZTD) is estimated in “near real time” eachhour in a set of stations covering all the Iberian Peninsula and archipelagos (about350 stations) for Numerical Weather Prediction by meteorological agenciesintegrated in the EUMETNET organization.

Hourly data are collected immediately after every hour from 15 different networks.Data in COST file format are sent to Met-Office (GB) around minute 30, whichdisseminates the information.

National coordinates: in collaboration with Autonomous Regions homogeneousETRF00 coordinates to all Spanish networks are being provided. Three regionalinstitutions and IGN are reprocessing data from 2011 to 2015 in order to stablish aconsistent reference frame, following the guidelines for EUREF densifications.

Volcanic monitoring system: continuous processing of a dedicated GNSSnetwork in Canary Islands, mainly in two of them (Tenerife and El Hierro) withrecent volcanic and seismic activity. Hourly and daily coordinates are obtained fortime series monitoring purposes.

Map of stations participating in the real-time service.

ALAC station at tide gauge. ACOR station at tide gauge. YEBE co-located station and VLBI antenna.

Examples of real-time service users.

Network processed in IBERRED project. IBERRED time serie.

Time series of HI03 and HI08 (El Hierro). HI08: volcanic monitoring station.

Acknowledgements to all institutions that provide data for these projects.

• J.A. Sánchez Sobrino, M. Valdés, M. A. Cano (2013): “E-GVAP, un proyecto europeo meteorológico con GNSS. Participación del IGN”. Topografía y cartografía: Revista del Ilustre Colegio Oficial de Ingenieros Técnicos en Topografía, ISSN 0212-9280, Vol. 28, Nº 165.

• M. Valdés, M. A. Cano, P. Gonzalo, J.A. Sánchez Sobrino (2014): "Actividades GNSS del Área de Geodesia del Instituto Geográfico Nacional (IGN)". VIII Asamblea Hispano-Lusa de Geodesia y Geofísica. Evora (Portugal), 29-31 enero 2014.

Bibliography