EUREF'03: National Report of Switzerland
New Developments in Swiss National Geodetic Surveying
11111111B. Vogel, E. Brockmann, P. Kummer, U. Marti, D. Schneider, A. Schlatter, A. Wiget and U. Wild, 2W. Gurtner
- Making available procedures for the transformation 1 Introduction
between old and new reference frames (position Beginning in 1988 the Federal Office of Topography and height) (swisstopo) has conceived a new national geodetic - Linking the Swiss Positioning Service swipos to reference system CHTRS95 which should replace the those of the neighboring countries (e.g. SAPOS) existing frames LV03 (position) and LN02 (height) - Practical application of GPS humidity measure-with its new reference frames CHTRF95 (global) and ments to meteorology LV95 (local). CHTRS95, which is closely related by a
geometric transformation to ETRS89, also consists of 2 Fundamental Station Zimmerwald a new height system, a geoid model on the cm level The fundamental station Zimmerwald is jointly oper-and a kinematic model. ated by the Astronomical Institute of the University of After 15 years most elements of the new system have Berne (AIUB) and the Swiss Federal Office of been realized and most of the data is available to the Topography (swisstopo). user. The fundamental station Zimmerwald together
with 5 EUREF stations links the national networks to 2.1 SLR observations
the European and worldwide reference frames. Since 1997, when the first SLR observations were Various geodetic measuring techniques such as SLR, performed with the new SLR system in Zimmerwald, GPS and gravimetry are already collocated at a continuously increasing number of observed passes Zimmerwald. As a contribution to the ECGN initiative, could be submitted to the International Laser Ranging the number of measuring techniques is presently Service (ILRS). being increased.
Although there was an almost two-month shutdown The Automated GPS Network (AGNES) with 29 of the station due to maintenance (re-coating of the permanently operating GPS stations is used for primary mirror), Zimmerwald ranked # 9 out of about various applications such as real-time positioning and 40 stations regarding the total number of collected GPS meteo. It is optimally integrated into the EUREF passes, and # 5 in the rating with respect to the permanent network. The national GPS network LV95 number of Lageos normal points. From March 16 to has been densified and includes 206 well-22, 2003, Zimmerwald collected the largest number of monumented control points. A large effort has been passes for that week worldwide. undertaken to establish a new height reference frame
Thanks to the possibility of automated and unat-LHN95 which, together with the new geoid, is
tended operation or remote control during limited compatible with the 3D frame of LV95.
times (typically a few hours per day), a nearly 24-hour Presently geodetic work is focused on the following tracking coverage can be realized with only two shifts tasks: per day. - Connecting geodetic networks (AGNES, LV95,
Zimmerwald was the first ILRS station to submit dual-LHN95 etc.) with the objective of making them
color range observations on a regular basis between compatible (GPS–leveling)
mid-August and December 2002. - Completing the combined kinematic adjustment of
2.2 GNSS observations - Improving the geoid model
- Developing a local–regional kinematic model Presently the following GNSS receivers are operating describing tectonic motion in Zimmerwald:
- Improving the access to geodetic data by the user - Trimble 4000 SSI receiver (main receiver, providing (Internet services) tracking data to the IGS)
1 swisstopo (Swiss Federal Office of Topography); Geodesy Division, Seftigenstrasse 264, CH-3084 Wabern, Switzerland, Phone:
++41 31 963 22 56, Fax: ++41 31 963 24 59, e-mail: firstname.lastname@example.org, Web-Site: http://www.swisstopo.ch 2 AIUB (Astronomical Institute of the University of Berne); Sidlerstrasse 5, CH-3012 Berne, Switzerland. Phone: ++41 31 631 85 99, Fax: ++41 31 631 38 69, e-mail: email@example.com
- Ashtech Z18 (combined GPS/GLONASS receiver) processing showed a good agreement of the two - Javad Legacy receiver (combined GPS/GLONASS methods (see chap.4).
receiver) Parallel to the software updates, the server archi-The Trimble receiver runs with the GPS Base Station tecture was enhanced. The VRS computation was Software and provides daily files to the IGS data separated from the data communication and the data centers. Furthermore, hourly files are generated and storage on the Web server. In addition, a new distributed with a time delay of a few minutes, and software tool allowing the VRS computation for post-are used for near real-time applications by the IGS and processing applications was installed on the AGNES other institutions. The delivery rate of the daily Web server. The new configuration provides a observation files was very high during the last three maximum flexibility for data communication (e.g. years: 99% for 2000, and nearly 100% for 2001 and data exchange over the Internet, see below). 2002. In addition, the Trimble receiver provides
The real-time service swipos-GIS/GEO and the cor-epoch-wise GPS data in real-time to the central
AGNES server, which is one of the currently 29 responding SAPOS service in Baden-Württemberg
(Germany) were connected over a direct phone line, AGNES stations (see chap. 3).
which will be replaced by an Internet connection as In addition to the main GPS receiver, two combined soon as possible. The data of 9 stations are exchanged GPS/GLONASS receivers are installed at Zimmerwald, on a real-time basis, allowing an improvement of the both providing data for the IGLOS-PP. This quality of VRS processing in the region along the International GPS Service Pilot Project is a follow-up border between Germany and Switzerland. project of the former IGEX-98 campaign and Connections to SAPOS in Bavaria (Germany) and to maintains a global station network and provides Austria are planned and will be realized within the precise orbits for the GLONASS satellites. next year.
2.3 Contribution to ECGN The developments of EUREF-IP were followed closely.
First tests were performed in August 2002 and Switzerland contributes to the ECGN project with showed good results even for RTK applications over various observations in Zimmerwald [Brockmann et Internet. Swisstopo would therefore like to become al., 2003]. an "Internet Broadcaster" within EUREF-IP for DGPS
correction data. The installation of the corresponding 3 Permanent GPS network AGNES and server infrastructure is planned for the end of 2003. positioning service
The Automated GPS Network of Switzerland (AGNES) 4 Analysis of permanent GPS networks reached its final configuration of 29 stations by the The permanent GPS networks analyzed at swisstopo end of 2001. During 2002 the last refinements of the are shown in Tab. 4-1. station installations were done, including an improved
lightning protection unit and a remote-accessible Network Stations Analysis interval; power switch for the station computers. In addition, Delay local ties and the connection to the old national first EUREF daily; after 21 order network LV03 were measured at 23 stations in 20 (1 AGNES) subnet days order to contribute to the determination of the
transformation parameters between the old (LV03) AGNES + daily; after 21 65 (29 AGNES) and the new reference frame (LV95). EUREF days subnet The overall performance of AGNES was excellent, and
AGNES + the availability of the RINEX data files on the Web hourly; after 0.5 EUREF 63 (29 AGNES) server was 99.1% (mean value over all stations). At 20 hours subnet stations the station outages were below the indicator
of 3 days/year, at 9 stations this value could not be Tab. 4-1: Routine GPS data analysis at swisstopo attained. These "critical stations" were identified, and
The data of the AGNES sites have been monitored organizational and technical actions were taken in
since the end of 1998 on a daily basis. In addition to order to improve the availability of the data.
the 29 AGNES sites, 40 EUREF permanent sites are For the real-time positioning service swipos-GIS/GEO, processed with the Bernese GPS Software Version 4.2 a new version of the Virtual Reference Station (VRS) [Hugentobler et al., 2001] using the final IGS orbit software was installed, which performed better with products with a time delay of 3 weeks. This respect to stability, initialization times and accuracy. monitoring allows the detection of possible site In addition, the new software version allows the movements. An updated multi-year solution, where storage of real-time estimates of the troposphere. the site coordinates and velocities are solved for, is Comparisons of these "real-time" tropospheric automatically generated after having processed an parameters with those of our geodetic post-additional week of data. The results are e.g. estimated
velocity and repeatability plots. As an example, the 5 National reference frame LV95 and
horizontal velocities relative to Zimmerwald are its relation to the old networks shown in Fig. 4-1.
5.1 The national reference frame LV95
The densification of the GPS network LV95 has been
completed on the national level. There are a total of
206 well-monumented control stations serving as the
basis for the reference frame. In order to ensure the
transition between the old and the new reference
frame, transformation programs were developed, one
each for height and position. These control points
together with the AGNES stations serve as a reliable
basis for the determination of the transformation
5.2 Transformation LV03 ; LV95
As in many other countries, the transformation be-
Fig. 4-1: Horizontal site velocities in ITRF00 (rela-tween the old reference frame (LV03), determined tive to Zimmerwald. The time span of the mainly by triangulation, and the new GPS reference sites with the longest “history” is summer frame (LV95) still has to be realized. Due to the dis-1998 till May 2004). tortions of the triangulation network in the order of
more than 1.5 m (see Fig. 5-1), a simple modeling of Since 1999 swisstopo has been active in the European the differences by means of a 4-parameter similarity project COST-716 (exploitation of ground-based GPS transformation does not give adequate results. A for climate and numerical weather prediction possible solution would be to divide the country into application). After a successful benchmarking [van der sub-regions and to use individual transformation Marel et al., 2001], swisstopo has been contributing parameters for each sub-region. But this would result zenith total delay estimates in near real-time (NRT-in ambiguous coordinates along the boundaries. ZTD) since December 2001. 95-98% of the solutions Another possibility that was chosen by several arrive at the data archive of the UK met office within 1 countries was to model the differences by polyno-hour and 45 minutes. mials of a certain degree. This method causes the MeteoSwiss used the NRT-ZTD estimates in a test problem of reversibility of the transformation and can study for numerical weather prediction. The numer-lead to unrealistic results in regions without known ical forecast models were computed for the different common points. test periods (summer, autumn, winter) in two Switzerland has chosen another method which is different schemes: a run with assimilated GPS-derived called FINELTRA (finite element transformation), ZTD estimates and a run without assimilated ZTDs. A whereby the whole territory is covered with triangles. comparison of the results showed a positive impact of For each of these triangles an affine transformation GPS [Guerova et al., 2002] for summer and a slightly with 6 parameters is defined. This method has the negative impact for winter. A by-product of the hourly following advantages: processing is the monitoring of the site coordinates.
- the transformation is continuous - no ambiguous Cumulative solutions averaging 12-24 hourly solutions
coordinates at the boundaries allow the detection of coordinate changes of the
- the transformation is reversible and works in both order of 2 cm.
directions Swisstopo will also be active in the follow-up Euro-- the common points which are used as transfor-pean project TOUGH "Targeting Optimal Use of GPS mation check points in both networks transform Humidity Measurements in Meteorology" (2003-2005). exactly to the coordinates of the other network
Since January 2003, ZTD values can also be extracted Up to now the mesh of triangles has been defined on from the real-time positioning software GPSNet 2.0 stndthe level of the 1 and 2 order triangulation points with accumulation intervals of 1 minute with a (Fig. 5-2) which allows a transformation in the order negligible time delay. of about 5 to 20 cm, depending on the region and the
quality of the old triangulation. Presently the cantonal The results of the different analyses are available on
surveying authorities are working on further http://www.swisstopo.ch/en/geo/pnac.htm.
densifying the triangles.
Since FINELTRA is a rather special solution which
cannot be implemented easily in GPS receivers, an
approximation of this method had to be developed,
where the differences between LV03 and LV95 are real-time. For a 1-km grid maximal differences are calculated in a regular grid of 1-km spacing. This grid usually better than 1 cm compared to the solution of can be stored directly in the GPS receivers and the FINELTRA.
surveyors obtain the still official LV03 coordinates in
Fig. 5-1 Differences LV95 minus LV03
the differences into one part that is a function of only
the horizontal position and into a second part that is a
function of the elevation as well. The first part (Fig.
5-3) is identical to the differences between LN02 and
normal heights, and reaches amounts between -20
and +10 cm. This part includes the distortions of LN02,
the influence of vertical movements and a part of the
influence of the gravity field. It shows practically no
correlation with height.
The second part of the differences, which is identical
to the difference between normal heights and
orthometric heights, works like a local scale factor. It
reaches amounts between -40 and +220 ppm. The stndFig. 5-2 Triangles defined by 1 and 2 order Bouguer anomalies are a very good approximation for
triangulation points this scale factor.
Therefore, the total of the differences are modeled by 5.3 Transformation LN02 ; LHN95 the function A similar problem as the one for the position is the
transformation of heights between the old leveling g(x,y)ΔBougH=H+f(x,y)H network LN02, which was adjusted without taking LHN95LN02ginto account the influence of the gravity field, and the
new orthometric height system LHN95. Due to the The transformation calls for one grid that represents special structures of leveling networks, an approach the differences between LN02 and normal heights with triangles, as it was used for position, is not f(x,y), and another grid of the Bouguer anomalies. recommendable. In addition, the differences between Near the leveling lines and in flatter areas, the LN02 and LHN95 show a strong correlation with the accuracy of the transformation is in the order of height. Therefore, an approach was chosen that splits
?2 mm. In mountainous regions the accuracy is de-Fig. 5-4 shows the total of the differences between creased and can reach amounts of up to 2 cm. LN02 and LHN95, which are between -20 and +60 cm.
The correlation with the height is clearly visible.
SH 50 SSH 3SH 23SH 6SH 9SH 58TG 157ZH 298SH 63SH 62SH 25TG 209SH 33TG 204TG 169TG 206TG 197SH 78TG 223TG 232DEU 132TG 179TG 177DEU 137TG 181TG 247TG 249DEU 140ZH 246ZH 266AG 38 KAG 37 KAG 36AG 42TG 259TG 34ZH 257TG 261AG 62AG 29AG 24SH 39AG 591ZH 253aZH 243TG 275ZH 232ZH 211DEU 151AG 73AG 3AG 2AG 10TG 11ZH 205BS 36BS 41TG 3ZH 220TG 4ZH 216AG 83AG 82ZH 202BS 39BS 3BS 1AG 95AG 145AG 148AG 115AG 120AG 149AG 122BS 18AG 205AG 103TG 42ZH 347AG 104BS 16BL 4aBL 112BL 19aAG 571AG 166TG 291ZH 197TG 44BL 15BL 9BL 10BL 12ZH 193ZH 340AG 171AG 562AG 563ZH 333TG 47JU 115AG 178AG 218BL 96AG 182AG 185SG 251SG 240SG 243SG 226AG 552AG 553TG 53AG 201AG 202AG 554BL 32AG 191AG 388AG 256AG 245AG 255SG 210SG 209SG 311SG 207JU 125SG 206BL 38BL 105BL 106BL 42BL 44BL 79BL 46BL 119BL 47SG 201AG 233ZH 172AG 540BL 85ZH 321ZH 320BL 89BL 121BL 127BL 135ZH 317AG 537SG 171SG 283SG 168SG 287ZH 170SG 302SG 301SG 276AG 224AG 534AG 357BL 142JU 141SG 165JU 143JU 144ZH 163BL 67BL 66ZH 302SG 293AG 521ZH 155SG 295SG 296aSG 345JU 148ZH 137JU 156JU 155BL 71BL 152AG 349BL 151AG 497AG 498JU 158SG 361ZH 4ZH 3SO 116ZH 16SO 111SO 113SO 132SO 104AG 339JU 105SO 100SO 131SO 98JU 170JU 171AG 440AG 330AG 326SO 85SO 84SO 83SO 95JU 100JU 93AG 321JU 180SO 74SG 379SG 377JU 91SG 117JU 181JU 182SG 116SG 114AG 476AG 416AG 429aSG 384AG 425SG 387JU 78SG 113ZH 61ZH 66BE J138SO 61AG 486AG 309BE J135BE J134SG 99BE J130SG 98SG 604SG 605AG 405AG 446ZH 118ZH 73ZH 79AG 298SG 660JU 66BE N222SG 14sSG 594SG 398ZH 85BE N218BE J111JU 61JU 60SG 589aBE J109SO 53BE J 96LU 131LU 130ZH 92SG 415SG 413AG 290JU 57FL 101SO 51SG 79SG 80SG 561LU 323SO 49LU 125JU 51ZH 96BE N300SZ 113SG 569SZ 112SO 27LU 320LU 118SZ 107BE J 19BE J 18BE J 20BE J 16SZ 1040.10 mSO 2BE J 12BE N329SG 71SG 69ZG 33SG 64BE N196SZ 150SZ 99JU 45LU 108LU 105LU 106BE J 9ZG 44BE J 37BE J 5ZG 86BE J 39BE J 3BE J 42BE N 79BE J 49ZG 17SG 480SG 485ZG 12ZG 13BE J 51BE J 50BE J 60BE N 70SG 56GL 5GL 4GL 23GL 6GL 18LU 159BE N 68BE N 65GL 16GL 30SG 503GL 58SG 5040.08 mBE J 67LU 91SG 491NE 125NE 124SG 51BE N347SG 518NE 297ZG 1SZ 92SZ 91SG 50BE N172BE N 46NE 295NE 293NE 121NE 115SG 47SZ 11BE N168NE 112SZ 81NE 288SZ 78SZ 80SG 42SZ 75LU 69SG 41LU 145SG 534SG 533NE 105NE 107BE N 42NE 284NE 285SZ 74SG 39BE N 36BE N156LU 36LU 34SG 34NE 97SG 647SG 36SG 35NE 276BE N1490.06 mLU 7NE 81LU 6SZ 25SZ 24LU 208GL 146LU 200LU 1SZ 68LU 204LU 25LU 176BE N374BE N373NE 139SZ 29GL 68LU 58LU 52NE 96BE N 24SZ 42BE N431BE N433NE 72BE N142LU 182NE 143NE 87NE 68NE 65SG 18aNE 83NE 60BE N135NE 150NE 55GL 87BE N 4NE 38NE 370.04 mNE 47NE 44GR 2 5NE 27NE 28NE 33GR 1418GR 1414NE 263NE 262GR 1410NE 257NW 7NE 156NE 252SZ 63GL 104GR 2 19NW 11NE 248NE 249NW 14NE 19NE 18FR 351FR 352GR 3337NE 235NE 236NE 222LU 254LU 258GR 2 24NE 163BE S 20BE S 3BE S 9BE S313GR 3332BE S104GR 2 29FR 321NE 167NE 165GR 2 37BE S3220.02 mUR 4FR 315BE S286UR 6UR 5BE S 83BE S263BE S 85GR 3328GL 124BE S215GL 118NE 169NE 180BE S218NE 179NE 200BE S112BE S339NE 171GR 3327NE 185NE 174BE S 95UR 10NE 173BE S273NE 188UR 275LU 282OW 22GR 1391LU 277GR 2 50FR 153UR 217UR 270UR 261NE 3UR 209UR 19UR 244UR 249UR 256UR 309UR 308UR 234GR 2 53GR 3318GR 1365GR 1364-0.00 mGR 1380NE 194FR 145UR 23VD O189FR 277GR 1136GR 2 59GR 1144BE S234VD O448GR 1149GR 2 63GR 2 61GR 2309UR 25GR 2 73GR 2 64FR 284FR 283FR 134OW 40VD O431GR 3302FR 250VD E120VD E115VD O428VD O427OW 44GR 2 69FR 265GR 3298GR 3293GR 2 84VD O410VD O406VD O170VD O409VD O408VD O174GR 3288GR 3287GR 1431GR 3465GR 2 85GR 3466FR 106FR 108-0.02 mGR 3282GR 2 89GR 3276VD O398GR 3275GR 3463GR 3274GR 1 96GR 1218BE S252FR 96BE S251VD O208GR 3255GR 3248GR 3247GR 1436GR 3251UR 41GR 3245OW 53GR 3269UR 42GR 1 81UR 44OW 57GR 3264GR 3262GR 3243FR 87OW 63BE O 12BE O 3BE O 4BE O156UR 49BE O147UR 201BE O178UR 199BE O168BE O170VD O222BE O167BE O191UR 50BE O349UR 204UR 198BE O346BE O343BE O352UR 195GR 1 61-0.04 mBE O362BE O356BE O358VD O382BE O364BE O366UR 206UR 53GR 3235GR 1 54UR 191BE O194BE O143BE O340BE O 33GR 1457VD O230GR 2180FR 80GR 2183BE O334VD O370BE O213BE O330VD O371UR 187BE O215BE O 37GR 1 43BE O327UR 65GR 1 41GR 1230BE O324BE O220BE O221VD O367GR 1 46GR 1 47aBE O130BE O134GR 3353GR 1246GR 2196BE O233GR 2197GR 2200BE O127BE O 49BE O 45GR 1 33aGR 1 33GR 1 34aGR 3345UR 71GR 1476BE O237BE O369BE O368GR 2208GR 1251GR 3224GR 3225GR 1256BE O243GR 1 19BE O 93BE O 95GR 3355GR 3378VD O358BE O470-0.06 mUR 77UR 80GR 1 17UR 78VD O356VD O361VD O360GR 3376UR 146GR 1479UR 149BE O 82BE O 83GR 1261VD O245VD O247VD O248GR 1 14GR 1482GR 3362BE O493BE O 68GR 1 6BE O511GOTT327GR 2213GR 1 12GR 2215GR 3219VD O351UR 138UR 136UR 97BE O405VD O348VD O347UR 128UR 127GR 3371UR 101UR 102bGR 3369UR 105aGR 3215GOTT332GR 1486VD O345VD O344GR 1490UR 286GR 3212BE O268UR 108UR 109FR 175BE O520FR 54UR 152UR 113GR 1493VD O265VD O341GOTT337BE O522GR 3208FR 48FR 47BE O282BE O286-0.08 mUR 156BE O289GR 1498UR 174UR 117GOTT341UR 163VD O336UR 178BE O422GR 1293GR 1300TI 1FR 32VS D 5UR 184VS D 8BE O423aBE O424aTI 7FR 29BE O531VD O284TI 604BE O314GR 1308GR 1309VS D 23VS D 34VS D 35VS D 28TI 10VS D 24VS D 26GR 2241VS D 39TI 12GR 3173GOTT639VS D 41TI 14TI 15TI 16VD O327FR 24TI 19TI 20VD O293VD O292BE O541VS D 48TI 22GR 2246-0.10 mGR 1318GR 2249TI 25GOTT634GR 2252GR 1346TI 36TI 40aFR 185GR 1324VD E 1VD E 2BE O546VD E 18TI 39GR 3161VD O 12GR 1330VD O 18VS D 54GR 1353TI 563VD O 27BE O442BE O441GR 1356FR 7VD E292VD E293TI 71TI 67FR 5BE O448GR 3 70GR 2289GR 3151TI 73VD E248BE O556BE O560BE O559GR 2283VS D 64GR 3140GR 3139GR 2267GR 2278BE O561VD E251GR 3 65GR 2272VD E485VD O 40VD E285BE O459GR 3 64-0.12 mVD E254BE O457BE O455VD E479VD E264VD E477VD O324VD E265VD O322LOET391VD E458VD E464TI 541VD O320VD O319VD E272VD E277GR 3 58VS D 81VD O318VD O317VD E300aVD E301VD O311VD O309VD O308LOET415TI 93VS D 86VD O 70TI 97GR 3 47TI 132LOET426VD O305VD E319VD E318LOET732VS D 93VD O 74-0.14 mVS D 96GR 3 42GR 3 41LOET724VS F161VD O 79VD O 76VD O 80VS F154LOET714BE O563GR 3103BE O564GR 3 38VS F150VS F148LOET706aTI 118TI 512VD E410GR 3 87GR 3 86GR 3 84VD E343GR 3 32VD E426GR 3 78GR 3 77VS F144VS F142VS D206VS D205-0.16 mVS D119VD E347VD E397VS D200TI 139TI 141VD O 97VD O 98VD E390VS D141VD E389SIMP032VD E386VS D197VD E353SIMP037VS D136VS D194VS D188SIMP045VD E358VS D170aVS D175VS D249VS D248VS D368VS D367SIMP051VS D157VS D254VS D255GR 3 21VS D156aVS D366VS D151VD E360VS D164VS F 1VS D369VS D407VS D158VS D370SIMP060VS D371-0.18 mVD E365SIMP077GE 52VS F138VS D267SIMP 37VS F 22VS F 21VS F 25VS D216VS D217GR 3 6VS D270VS D271VS D275VS D273SIMP 53VS F 36VS D219GE 44VS F 34VS F 31SIMP 58VS D277GE 37VD E380VS F127SIMP 67VS D345-0.20 mGE 1GE 2SIMP 18SIMP 19GE 7GE 6TI 176TI 177ITA 10VS D301FRA 114VS D296VS D304GE 32VS D286VS D294GE 30VS D221TI 192TI 206VS D291VS D289VS F121TI 217aVS D226TI 473TI 474TI 231TI 236TI 241TI 245VS F107TI 313VS F101VS D231VS F 85aVS F 93TI 251VS F 86VS F 90VS F 91VS F 83VS F 78VS F194TI 328VS F202VS F272VS F281VS F284VS F290VS F293TI 340VS F233VS D241TI 344VS F243TI 360VS F249TI 363TI 379VS F255TI 384VS F257TI 398VS F260TI 399VS F262VS F264VS F267VS F269TI 402TI 509TI 403TI 406TI 460
Fig. 5-3 Differences between LN02 and normal heights
0.65 m0.60 m0.55 m0.50 m0.45 m0.40 m0.35 m0.30 m0.25 m0.20 m0.15 m0.10 m0.05 m-0.00 m-0.05 m-0.10 m-0.15 m-0.20 m
Fig. 5-4: Differences between LHN95 and LN02
6.2 National control points 6 Maintenance of networks in This maintenance concept includes the following Switzerland networks: The organization and the revision cycle of the various - the permanent stations of the Automated GPS networks are defined in the internal report 02-01 Network of Switzerland, AGNES (including the "Landesvermessung der Schweiz, Unterhaltskonzept fundamental station Zimmerwald) der geodätischen Netze" [Santschi et al., 2002]. The - stations of the GPS network LV95 revision work, quality standards, data management, - transformation fiducial points for the conversion of documentation and archiving are defined for the the national triangulation network LV03 ; national various categories. All stations of the European GPS control network LV95 (first order points) networks are integrated in these categories and thus - control points of the old LV03 (first order points) their maintenance is ensured. - height control points (benchmarks) of the national
height network LHN95 (first order points) 6.1 EUREF stations - test networks of the national survey This maintenance concept includes the following
The organization and revision cycles are shown in Tab. networks:
6-1. - non-permanent EUREF stations - fundamental station Zimmerwald
number distance establishment maintenance Tasks of sites km when what where when
1 250 -- operation/measurement CH perm./yearly Zimmerwald
3 150 if required inspection CH every 5 years EUREF
29 50 if required operation/inspection CH perm./every 5 years AGNES
206 15 if required inspection CH every 5 years LV95
inspection Centr.Plateau every 15 years 3000 5 no new sites First order inspection Prealps/Jura every 25 years points 1) Alps if required (LV03)
9000 3 if required inspection CH every 15 years First order
2 0-5 if required inspection CH every 5 years Test nets
1) Maintenance will be discontinued when LV95 is introduced as the reference frame for all surveying applications in
Tab. 6-1 Maintenance concept of the Swiss control points
In the scope of the transition from the old triangula-7 Current projects tion network LV03 to the new GPS control network
LV95, it is very important to maintain and keep up the 7.1 Control point data service data of the control points. In order to achieve this goal, The schedule of the initial project "Datashop Geo-close collaboration is required between the Geodesy desy" was revised and renamed "Control point data Division, the Federal Directorate for Cadastral service" in June 2001. The focus of this project is no Surveying and the cantons. Currently a Java user longer in just preparing the data of the control points interface is being programmed and the data from for use on the Internet, but in establishing and swisstopo and the cantons are being imported. updating a central database of the control points together with the surveying authorities of the cantons, whereby the data will be made available to customers via the so-called "Central Point of Delivery".
- finishing the scans for the site documentation 7.2 GIS for the national border
- developing the new database in the scope of the The responsibility of the technical administration and project "Control point data service" (see chap. 7.1) the maintenance of the national border network lie with the Geodesy Division. For some time already, the The introduction of LHN95 as the official vertical ref-main focus has been on drafting a new maintenance erence frame for cadastral surveying was rejected by and documentation concept on the one hand, and on the surveying authorities of the cantons. Therefore, coordinating this information with the official the valid height reference frame for official cadastral cadastral surveying data on the other hand. Therefore, surveying is still the "old" LN02. However, LHN95 will in addition to the daily business, the efforts were remain indispensable for applications in national concentrated on this concept, which resulted in the surveying, scientific research, for the integration of new project "National Border". European height systems, and for large engineering The project consists of the following tasks: projects such as the new Alpine railway tunnels
(AlpTransit). As a consequence, increased significance - securing and maintaining the points of the national will be placed on the software for the transformation border together with the neighboring countries between LN02 and LHN95. - modernizing the data management and docu-
mentation 7.4 Swiss 4D: Establishing a kinematic - making the coordinates available in the European
model for Switzerland reference frame ETRF89 as well as in the reference
frames of the neighboring countries Based on the data of the Swiss permanent GPS - preparing the data and their integration in the GIS of network AGNES and repeated measurements, the official cadastral survey and in the topographic swisstopo is developing a kinematic model in col-database laboration with the Geodesy and Geodynamics Lab of
the Swiss Federal Institute of Technology in Zürich, The data management is to be part of a GIS. The which will take into account recent tectonic same instrument should also be used for the ad-movements (see Fig. 7-1). ministration of the boundaries between cantons,
districts and municipalities. In addition, the data The determination of a local–regional kinematic model should be revised and made available in the model for Switzerland (CHKM95) is an essential geographic data standard INTERLIS in order to component of the new definition of the Swiss geo-guarantee a uniform data transfer. This conversion detic reference system CHTRS95. CHKM95 describes should be realized by the end of 2007. regional movements in Switzerland relative to the
European reference system ETRS89 as well as local 7.3 New national height system LHN95 movements in the geodetic networks LV95 and The activities in 2002 were mainly focused on the LHN95 in all three dimensions.
following subjects: Last but not least, the deformation of space and time - integrating the new observations 2001/02 of the 1st will be analysed so that tectonic interpretations are order leveling network and the connections to the possible. Continuous spatial velocity or strain rate AGNES and LV95 stations fields are suited for the description of the deformation - documenting the network concept LHN95; processes. Also, seismic and geological information is observation schedule 2004-2008 of interest. - collaboration in the CHGeo2003 campaign [Brockmann et al., 2003]
- coordination with the users of the official cadastral survey and GIS
- developing the software module for the transition
LHN95 ; LN02 (see chap. 5.3)