# Presentation: 731241

## FGCS  Methodology

- Joe Evjen, Chair

## Agenda

- Recent Guidelines
- OPUS (all-inclusive)
- Datasheet Format

## Recent Guidelines

- Agenda item 1)

## Recent Guidelines

- Heights
- Bench Mark Reset
- GPS-derived Orthometric Heights
- Real-Time
- Classical RTK
- Guidelines for establishing CORS
*Developing: Guidelines for establishing RTN*

## OPUS (all-inclusive)

- Agenda item 2)

## 				WHAT IS OPUS?

**O**n-line **P**ositioning                                                     **U**ser **S**ervice

- Fast & easy access     to the NSRS (**National Spatial Reference System)**  for GPS users

**Notes:**
Now I would like to spend the remainder of our time talking about OPUS the ON-line Positioning User Server.

This program provides faster and easier access 
to the National Spatial Reference System.

I’m probably the number one fan of OPUS

I submit over a 150 runs a month 
to check the stability of the cooperative  base stations.

I find it very easy to use and very accurate.

## Why do we need OPUS?

- Recognize most positioning done with GPS
- Want to provide fast, accurate, consistent, reliable access to NSRS
- CORS data alone does not ensure consistency
- OPUS
- NGS computers
- NGS software
- Standard parameterization
- Standard coordinates/velocities
- Your machine talks to our machine

## Quick Link to OPUS from NGS Home Page

- www.ngs.noaa.gov

## CORS Network: Where We are Today

-  1191 National CORS
-  190+ Cooperative CORS

**National CORS**

**CORS Network: Where We are Today**

## Baseline Plot National

**Notes:**
Baseline Plot

As you can see there a few more sites here.
There are 541 national CORS.  The ratio is about ...
4.5 to 1

## How does OPUS compute your position?

- CORS solution 1

- solution 3

- solution 2

**How does OPUS compute your position?**

- 3 single baselines computed

- 3 positions averaged —
- simple mean (equal weights)

## DEFAULTS:
 $$$ receiver
 hours of data
 one receiver
 no archive
 no delimiters
 US only
 GPS only

** ****$$$ receiver**
** ****hours of data**
** ****one receiver**
** ****no archive**
** ****no delimiters**
** ****US only**
** ****GPS only**

_**[OPUS](http://www.ngs.noaa.gov/OPUS/)**__** in the works**_

**¢¢ ****receivers****	****	***_[OPUS ](http://www.ngs.noaa.gov/OPUS/OPUS_GIS.html)__[mapper](http://www.ngs.noaa.gov/OPUS/OPUS_GIS.html)_
**minutes**** ****of data****	****OPUS-RS****	****	**
**multiple ****receivers****	*****OPUS-projects**
**share**** ****results****	****	*****OPUS-DB**
**delimited**** ****results****	****OPUS-XML****	**
**global**** ****results****	****	*****OPUS-global**
**GNSS**** signals****	****	*****OPUS-GNSS**
****** ****heights****	****	*****OPUS-leveling**

- Operational components are available at http://www.ngs.noaa.gov/OPUS/
- * Prototype components are available at  http://beta.ngs.noaa.gov/OPUS/

**Notes:**
OPUS Database
Stream-lined method for users to publish their results
User registration - ID  & password, Validation process, 
OPUS solutions can be integrated into the NGS database
Data elements from OPUS , Additional metadata
Submission review by user and NGS

OPUS Projects
Managers can define a project
Process any number of stations under a project, Project can span several days to weeks, Contract work
Project processing
Each dataset sent to OPUS but identified with a project, Results returned to submitter a few minutes later, Manager can monitor processing and submission
Final adjustment
Entire project adjusted as one campaign, Review & submission to NGS

OPUS Rapid Static
User requests, Single frequency capability, Rapid static solutions (10 – 15 minutes of data), Will be processed with carrier phases
Accurate to several centimeters, Need more accurate ionospheric and tropospheric modelling In development at OSU and NGS

OPUS GIS
Compute a differential pseudorange solution for less expensive GPS receivers
Aimed at the GIS community who do not require cm level accuracies
Allows processing in a consistent approach and “certify” their locations in the NSRS
Generate rapid static solution from seconds or minutes of data
Accuracies: A few decimeters to a meter horizontally
Pilot project underway in Phoenix, Arizona

## Datasheet format

- Agenda item 3)

## Datasheet Basics

**The NGS Data Sheet**
**See file dsdata.txt for more information about the datasheet.**
**DATABASE = Sybase ,PROGRAM = datasheet, VERSION = 7.56**
**1        National Geodetic Survey,   Retrieval Date = NOVEMBER 20, 2007**
** ****AE8289 *************************************************************************
** ****AE8289  CBN         -  This is a Cooperative Base Network Control Station.**
** ****AE8289  TIDAL BM    -  This is a Tidal Bench Mark.**
** ****AE8289  DESIGNATION -  602**
** ****AE8289  PID         -  AE8289**
** ****AE8289  STATE/COUNTY-  MN/ST LOUIS**
** ****AE8289  USGS QUAD   -  DULUTH (1993)**
** ****AE8289**
** ****AE8289                         *CURRENT SURVEY CONTROL**
** ****AE8289  ___________________________________________________________________**
** ****AE8289* NAD 83(2007)-  46 46 29.11030(N)    092 05 37.38857(W)     ADJUSTED  **
** ****AE8289* NAVD 88     -       184.348  (meters)     604.82   (feet)  ADJUSTED  **
** ****AE8289  ___________________________________________________________________**
** ****AE8289  EPOCH DATE  -        2002.00**
** ****AE8289  X           -    -159,876.198 (meters)                     COMP**
** ****AE8289  Y           -  -4,373,152.968 (meters)                     COMP**
** ****AE8289  Z           -   4,624,765.065 (meters)                     COMP**
** ****AE8289  LAPLACE CORR-          -3.07  (seconds)                    DEFLEC99**
** ****AE8289  ELLIP HEIGHT-         156.113 (meters)          (02/10/07) ADJUSTED**
** ****AE8289  GEOID HEIGHT-         -28.19  (meters)                     GEOID03**
** ****AE8289  DYNAMIC HT  -         184.373 (meters)     604.90  (feet)  COMP**
** ****AE8289**
** ****AE8289  ------- Accuracy Estimates (at 95% Confidence Level in cm) --------**
** ****AE8289  Type    PID    Designation                      North   East  Ellip**
** ****AE8289  -------------------------------------------------------------------**
** ****AE8289  NETWORK AE8289 602                               0.47   0.37   0.76**
** ****AE8289  -------------------------------------------------------------------**
** ****AE8289  MODELED GRAV-     980,748.1   (mgal)                       NAVD 88**
** ****AE8289**
** ****AE8289  VERT ORDER  -  FIRST     CLASS II**
** ****AE8289**
** ****AE8289.The horizontal coordinates were established by GPS observations**
** ****AE8289.and adjusted by the National Geodetic Survey in February 2007.**

- what's on a datasheet
- Position
- Accuracy
- How to locate and identify
- help files (dsdata.txt, glossary, ...)

## Web Statistics

**Web Statistics**

|  | 2005 | 2006 | 2007 | 2008* |
| --- | --- | --- | --- | --- |
| Datasheets downloaded
 (including shapefiles) | 6.0 million | 8.3 million | 6.2 million | 9.2 million |
| CORS retrievals
(User-friendly + FTP) | 3.9million | 5.7 million
 | 6.2 million | 12.1 million |
| OPUS solutions
 | 130,000
 | 167,000 | 233,000 | 239,000 |

*** extrapolated from 7 months**

## OPUS Output - Standard

-  1008   NOTE:  Antenna offsets supplied by the user were zero.  Coordinates
-  1008   returned will be for the antenna reference point (ARP).
-  1008
-                               NGS OPUS SOLUTION REPORT
-                               ========================
-       USER: jeff.olsen@noaa.gov                     DATE: January 13, 2006
- RINEX FILE: corv059f.05o                            TIME: 19:08:14 UTC
-   SOFTWARE: page5  0601.10 master3.pl              START: 2005/02/28  05:00:00
-  EPHEMERIS: igs13121.eph [precise]                  STOP: 2005/02/28  06:59:30
-   NAV FILE: brdc0590.05n                        OBS USED:  4228 /  4314   :  98%
-   ANT NAME: ASH700936B_M    NONE             # FIXED AMB:    25 /    29   :  86%
- ARP HEIGHT: 0.0                              OVERALL RMS: 0.013(m)
-  REF FRAME: NAD_83(CORS96)(EPOCH:2002.0000)            ITRF00 (EPOCH:2005.1596)
-          X:     -2498423.165(m)   0.018(m)          -2498423.872(m)   0.018(m)
-          Y:     -3802822.048(m)   0.021(m)          -3802820.836(m)   0.021(m)
-          Z:      4454737.695(m)   0.024(m)           4454737.792(m)   0.024(m)
-        LAT:   44 35  7.91054      0.002(m)        44 35  7.92698      0.002(m)
-      E LON:  236 41 43.48129      0.014(m)       236 41 43.42434      0.014(m)
-      W LON:  123 18 16.51871      0.014(m)       123 18 16.57566      0.014(m)
-     EL HGT:          107.485(m)   0.034(m)               107.108(m)   0.034(m)
-  ORTHO HGT:          130.010(m)   0.043(m) [Geoid03 NAVD88]
-                         UTM COORDINATES    STATE PLANE COORDINATES
-                          UTM (Zone 10)         SPC (3601 OR N)
- Northing (Y) [meters]     4936954.907           105971.557
- Easting (X)  [meters]      475821.322          2277335.385
- Convergence  [degrees]    -0.21381402          -1.98897497
- Point Scale                0.99960719           0.99994603
- Combined Factor            0.99959034           0.99992918
- US NATIONAL GRID DESIGNATOR: 10TDQ7582136955(NAD 83)
-                               BASE STATIONS USED
- PID       DESIGNATION                        LATITUDE    LONGITUDE DISTANCE(m)
- AH2489 NEWP NEWPORT CORS ARP               N443506.072 W1240342.736   60138.7
- AJ6959 CHZZ CAPE MEARS CORS ARP            N452911.437 W1235841.187  113322.4
- DH4503 P376 EOLARESVR_OR2004 CORS ARP      N445628.313 W1230608.100   42648.2
-                  NEAREST NGS PUBLISHED CONTROL POINT
- AH2486      CORVALLIS CORS ARP             N443507.910 W1231816.519       0.0

- OPUS Output - *Standard*

- FILE: corv0590.05o 000416827
-  1008   NOTE:  Antenna offsets supplied by the user were zero.  Coordinates
-  1008   returned will be for the antenna reference point (ARP).
-  1008
-                               NGS OPUS SOLUTION REPORT
-                               ========================
-       USER: jeff.olsen@noaa.gov                     DATE: January 13, 2006
- RINEX FILE: corv059f.05o                            TIME: 19:08:14 UTC
-   SOFTWARE: page5  0601.10 master3.pl              START: 2005/02/28  05:00:00
-  EPHEMERIS: igs13121.eph [precise]                  STOP: 2005/02/28  06:59:30
-   NAV FILE: brdc0590.05n                        OBS USED:  4228 /  4314   :  98%
-   ANT NAME: ASH700936B_M    NONE             # FIXED AMB:    25 /    29   :  86%
- ARP HEIGHT: 0.0                              OVERALL RMS: 0.013(m)
-  REF FRAME: NAD_83(CORS96)(EPOCH:2002.0000)            ITRF00 (EPOCH:2005.1596)
-          X:     -2498423.165(m)   0.018(m)          -2498423.872(m)   0.018(m)
-          Y:     -3802822.048(m)   0.021(m)          -3802820.836(m)   0.021(m)
-          Z:      4454737.695(m)   0.024(m)           4454737.792(m)   0.024(m)
-        LAT:   44 35  7.91054      0.002(m)        44 35  7.92698      0.002(m)
-      E LON:  236 41 43.48129      0.014(m)       236 41 43.42434      0.014(m)
-      W LON:  123 18 16.51871      0.014(m)       123 18 16.57566      0.014(m)
-     EL HGT:          107.485(m)   0.034(m)               107.108(m)   0.034(m)
-  ORTHO HGT:          130.010(m)   0.043(m) [Geoid03 NAVD88]
-                         UTM COORDINATES    STATE PLANE COORDINATES
-                          UTM (Zone 10)         SPC (3601 OR N)
- Northing (Y) [meters]     4936954.907           105971.557
- Easting (X)  [meters]      475821.322          2277335.385
- Convergence  [degrees]    -0.21381402          -1.98897497
- Point Scale                0.99960719           0.99994603
- Combined Factor            0.99959034           0.99992918
- US NATIONAL GRID DESIGNATOR: 10TDQ7582136955(NAD 83)
-                               BASE STATIONS USED
- PID       DESIGNATION                        LATITUDE    LONGITUDE DISTANCE(m)
- AH2489 NEWP NEWPORT CORS ARP               N443506.072 W1240342.736   60138.7
- AJ6959 CHZZ CAPE MEARS CORS ARP            N452911.437 W1235841.187  113322.4
- DH4503 P376 EOLARESVR_OR2004 CORS ARP      N445628.313 W1230608.100   42648.2
-                  NEAREST NGS PUBLISHED CONTROL POINT
- AH2486      CORVALLIS CORS ARP             N443507.910 W1231816.519       0.0

- <?xml version="1.0" encoding="UTF-8"?>
- <OPUS_SOLUTION>
-   <USER_INFORMATION>
-     <USER_EMAIL>           joe.evjen@gmail.com    </USER_EMAIL>
-     <SOLUTION_DATE>        February 19, 2008      </SOLUTION_DATE>
-     <SOLUTION_TIME>        01:16:22 UTC           </SOLUTION_TIME>
-     <RINEX_FILE_NAME>      zzyy1500.07o           </RINEX_FILE_NAME>
-   </USER_INFORMATION>
-   <DATA_INFORMATION>
-     <SOFTWARE>
-       <PAGES_VERSION>      page5  0612.06         </PAGES_VERSION>
-       <OPUS_VERSION>       master3.pl             </OPUS_VERSION>
-     </SOFTWARE>
-     <EMPHEMERIS>           igs14293.eph [precise] </EMPHEMERIS>
-     <NAV_FILE>             brdc1500.07n           </NAV_FILE>
-     <ANTENNA_NAME>         TRM41249.00     NONE   </ANTENNA_NAME>
-     <ARP_HEIGHT>           0.0                    </ARP_HEIGHT>
-     <START_TIME>           2007/05/30  00:00:00   </START_TIME>
-     <END_TIME>             2007/05/30  23:59:00   </END_TIME>
-     <OBS_USED>
-       <NUMBER_USED>        52955                  </NUMBER_USED>
-       <TOTAL_OBS>          55069                  </TOTAL_OBS>
-       <PERCENTAGE>         96                     </PERCENTAGE>
-     </OBS_USED>
-     <FIXED_AMB>
-       <NUMBER_FIXED>       218                    </NUMBER_FIXED>
-       <NUMBER_AMB>         242                    </NUMBER_AMB>
-       <PERCENTAGE>         90                     </PERCENTAGE>
-     </FIXED_AMB>
-     <OVERALL_RMS UNIT="m"> 0.021                  </OVERALL_RMS>
-   </DATA_INFORMATION>
-   <POSITION>
-     <REF_FRAME>            NAD_83(CORS96)         </REF_FRAME>
-     <EPOCH>                2002.0000              </EPOCH>
-     <COORD_SET>
-       <RECT_COORD>
-         <COORDINATE AXIS="X" UNIT="m" UNCERTAINTY="0.003"> -496255.901 </COORDINATE>
-         <COORDINATE AXIS="Y" UNIT="m" UNCERTAINTY="0.022"> -5510741.494 </COORDINATE>
-         <COORDINATE AXIS="Z" UNIT="m" UNCERTAINTY="0.017"> 3162058.243 </COORDINATE>
-       </RECT_COORD>
-       <ELLIP_COORD>
-         <LAT>
-           <DEGREES> 29 </DEGREES>
-           <MINUTES> 54 </MINUTES>
-           <SECONDS> 48.44070 </SECONDS>
- <UNCERTAINTY> 0.003 </UNCERTAINTY>
- <UNCERTAINTY_UNIT>m </UNCERTAINTY_UNIT>
-  </LAT>
- <EAST_LONG>
- <DEGREES>264 </DEGREES>
- <MINUTES>51</MINUTES>
- <SECONDS>15.31122</SECONDS>
- <UNCERTAINTY>0.002</UNCERTAINTY>
- <UNCERTAINTY_UNIT>m</UNCERTAINTY_UNIT>
- </EAST_LONG>
- <EL_HEIGHT>
- <VALUE>-7.199</VALUE>
- <UNCERTAINTY>0.027</UNCERTAINTY>
- <UNCERTAINTY_UNIT>m</UNCERTAINTY_UNIT>
- </EL_HEIGHT>
- </ELLIP_COORD>
- </COORD_SET>
- </POSITION>
- <POSITION>
- <REF_FRAME>ITRF00 (EPOCH:2007.4096)</REF_FRAME>
- <EPOCH>2007.4096</EPOCH>
- <COORD_SET>
- <RECT_COORD>
- <COORDINATE AXIS="X" UNIT="m" UNCERTAINTY="0.003">-496256.585</COORDINATE>
- <COORDINATE AXIS="Y" UNIT="m" UNCERTAINTY="0.022">-5510740.027</COORDINATE>
- <COORDINATE AXIS="Z" UNIT="m" UNCERTAINTY="0.017">3162058.057</COORDINATE>
- </RECT_COORD>
- <ELLIP_COORD>
- <LAT>
- <DEGREES>29</DEGREES>
- <MINUTES>54</MINUTES>
- <SECONDS>48.45813</SECONDS>
- <UNCERTAINTY>0.003</UNCERTAINTY>
- <UNCERTAINTY_UNIT>m</UNCERTAINTY_UNIT>
- </LAT>
- <EAST_LONG>
- <DEGREES>264</DEGREES>
- <MINUTES>51</MINUTES>
- <SECONDS>15.28092</SECONDS>
- <UNCERTAINTY>0.002</UNCERTAINTY>
- <UNCERTAINTY_UNIT>m</UNCERTAINTY_UNIT>
- </EAST_LONG>
- <EL_HEIGHT>
- <VALUE>-8.505</VALUE>
- <UNCERTAINTY>0.027</UNCERTAINTY>
- <UNCERTAINTY_UNIT>m</UNCERTAINTY_UNIT>
- </EL_HEIGHT>
- </ELLIP_COORD>
- </COORD_SET>
- </POSITION>
- <ORTHO_HGT UNCERTAINTY="0.037" UNIT="m" SOURCE="[Geoid03 NAVD88]">20.154</ORTHO_HGT>
- <PLANE_COORD_INFO>
- <PLANE_COORD_SPEC TYPE="UTM" ZONE="15">
- <NORTHING UNIT="m">3311130.625</NORTHING>
- <EASTING UNIT="m">292843.826</EASTING>
- <CONVERGENCE UNIT="deg">-1.07044705</CONVERGENCE>
- <SCALE>1.00012949</SCALE>
- <CF>1.00013062</CF>
- </PLANE_COORD_SPEC>
- <PLANE_COORD_SPEC TYPE="SPC" ZONE="4204(TXSC
- )">
- <NORTHING UNIT="m">4236668.327</NORTHING>
- <EASTING UNIT="m">972105.452</EASTING>
- <CONVERGENCE UNIT="deg">1.88824726</CONVERGENCE>
- <SCALE>0.99991407</SCALE>
- <CF>0.99991520</CF>
- </PLANE_COORD_SPEC>
- <USNG>15RTP9284411131(NAD 83)
- </USNG>
- </PLANE_COORD_INFO>
- <BASE_STATION_USED>
- <PID>DE5999</PID>
- <STATION_ID>ADKS</STATION_ID>
- <DESIGNATION>ADDICKS 1795 CORS ARP</DESIGNATION>
- <LATITUDE>N294727.47185</LATITUDE>
- <LONGITUDE>W0953511.04262</LONGITUDE>
- <DISTANCE>44692.309</DISTANCE>
- </BASE_STATION_USED>
- <BASE_STATION_USED>
- <PID>DJ8995</PID>
- <STATION_ID>ROD1</STATION_ID>
- <DESIGNATION>ROD1 CORS ARP</DESIGNATION>
- <LATITUDE>N300420.45377</LATITUDE>
- <LONGITUDE>W0953136.45801</LONGITUDE>
- <DISTANCE>40769.489</DISTANCE>
- </BASE_STATION_USED>
- <BASE_STATION_USED>
- <PID>DH3612</PID>
- <STATION_ID>TXLI</STATION_ID>
- <DESIGNATION>LIBERTY CORS ARP</DESIGNATION>
- <LATITUDE>N300321.18092</LATITUDE>
- <LONGITUDE>W0944615.67967</LONGITUDE>
- <DISTANCE>39457.656</DISTANCE>
- </BASE_STATION_USED>
- <NGS_PUBLISHED_CONTROL_POINT>
- <PID>AA9861</PID>
- <DESIGNATION>LAKE HOUSTON 2050 CORS L1 PHS </DESIGNATION>
- <LATITUDE>N295448.44005</LATITUDE>
- <LONGITUDE>W0950844.68949</LONGITUDE>
- <DISTANCE>0.000</DISTANCE>
- </NGS_PUBLISHED_CONTROL_POINT>
- <NOTE> This position and the above vector components were computed without any
- knowledge by the National Geodetic Survey regarding the equiqment or
- field operating procedure used. </NOTE>
- </OPUS_SOLUTION>

- OPUS Output - *XML*

**Notes:**
WHAT DOES THE OPUS OUTPUT LOOK LIKE
OPUS was designed to be a one page document that was simple and easy to read.
There’s basically three sections to the it.  
The first part is information about the dataset you submitted and the software used.
Here I would check your antenna name and the height you entered.  
If you don’t have the correct antenna, well, you know.
Over here, you have the number of possible observations vs the number used, you want to be in, say the 90% range.
Next is the number and ratio of fixed ambiguities and again I like to see this number pretty high at least around 80% if not better.
And I like the overall RMS to be under three.
The second part is the meat and potatoes, the coordinates you were looking for.
You have your NAD83 (CORS96) position reported at the 2002.0 epoch and ITRF00 coordinates  at the epoch of the midpoint of your data.
Coordinates are reported in both the Cartesian xyz, and geodetic coordinates systems. 
The Orthometric ht. is based on the current geoid model.
You have your UTM coordinates, your US National Grid Designator, and your State Plane coordinates if you chose that option.
Do you remember I said that OPUS performs 3 independent solutions?  
These numbers to the right of the solution are Peak to Peak errors.  
They are shown for both coordinates systems and may differ between the two.  
Peak to peak errors are the difference between the max and min values of the 3 individual solutions.
These numbers are indicative of the CORS that were used in the processing. 
 If you have large peak to peaks, say over 4 or 5 cm or so, I would try to determine which CORS is the problem by selecting different ones.  
Hopefully in the future we will have a “do not use” menu much as there is a choice menu.
And the third part lists which Base Stations were used in the solution along with their position and the distance from the GPS station being solved for.
The closest published station is shown,  and in this case, it is itself since this is a published CORS.
And of course the ever more popular disclaimer is at the bottom of every solution.
Now I want you to notice that this solution used the precise orbits.