# Presentation: 167372

## The National Geodetic Survey’s Cooperative CORS Program

**NGS Convocation**
- October 24-28, 2005
- Don Haw
- Coop CORS Manager
- National Geodetic Survey

- http://www.ngs.noaa.gov/CORS/Coop

**Notes:**

Why have a “cooperative” CORS?
We started Cooperative CORS several years ago in order for those agencies and organizations that were not part of the National CORS but wanted to be part of the National Spatial Reference System.  
It turns out that there is an added bonus to being a Coop CORS site.... And it is the fact that anyone wanting the Coop data had to visit that organizations web site to get it.  Not only is this organization now part of the NSRS, but are getting free advertising.

It was only recently that we had begun producing daily solutions for the Coop CORS.  Before Jan 2005, the Coop team would average 3 days of data once a month and see how the new position differed from the published position.  If the difference was greater than the CORS tolerance, a new position was entered into the database.

A better way... Is to calculate a position daily, and observe the changes over a smaller time interval.

I would like to show you how we collect and process the Coop CORS data to produce a daily solution and how it differs slightly from National CORS.

## Coop vs. National

- Web page shows status of sites
- Data downloaded daily to compute position using metadata in NGS Database
- If data not present for solution, no daily position will be calculated. Will NOT download data to archive.
- Data removed after 11 days

**Notes:**
Coop CORS vs. National CORS

Coop has a Web page that displays the status of the sites.  National has a link to a directory where text files can be viewed

Coop collects the data from the many sites using Java and Perl programs.  National uses individual Korn Shell scripts, but are in the process of changing over to the Coop CORS method

Coop CORS will not look for data older than 7 days.  If the are  no data for a particular site at 10 pm Eastern time.... no daily position.  National CORS will expend much effort to find missing data in order to archive it. The primary difference between the 2 is that you get National CORS data from the NGS server and you get Coop CORS data from the Coop member.

Coop removes data after 15 days, but it is available at the participants web site.  National keeps all data, but DOES decimated the data to 30 seconds after 30 days for archiving.  The CORS West collector in Boulder, CO is considering archiving raw data and rinex at its original rate.

## Coop vs. National

- National CORS outnumbers Coop CORS by nearly 7 to 1
- Station Log and Data are the responsibility of the participant
- Not involved in multiyear solution, yet
- OPUS will not automatically select Coops

**Notes:**
Coop vs. National (cont.)

With Coop, the station log and data are the responsibility of the group supplying the data.  National keeps the station log and data in house
Coop is not involved in the multi-year solution to better determine velocities.... Yet.
OPUS will not look for a Coop CORS in its processing unless the user selects a Coop CORS site. 

## Coop vs. National

- Web page shows status of sites
- Data downloaded daily to compute position using metadata in NGS Database
- If data not present for solution, no daily position will be calculated.
- Data removed after 11 days

**Notes:**
Coop CORS vs. National CORS

Coop has a Web page that displays the status of the sites.  National has a link to a directory where text files can be viewed

Coop collects the data from the many sites using Java and Perl programs.  National uses individual Korn Shell scripts, but are in the process of changing over to the Coop CORS method

Coop CORS will not look for data older than 7 days.  If the are  no data for a particular site at 10 pm Eastern time.... no daily position.  National CORS will expend much effort to find missing data in order to archive it. The primary difference between the 2 is that you get National CORS data from the NGS server and you get Coop CORS data from the Coop member.

Coop removes data after 15 days, but it is available at the participants web site.  National keeps all data, but DOES decimated the data to 30 seconds after 30 days for archiving.  The CORS West collector in Boulder, CO is considering archiving raw data and rinex at its original rate.

## Coop_status.html

**Notes:**
Coop_status.html

This is the Coop status web page.  It gives us a quick look at where I am in the processing of the site.  It supplies links to the participants web page so we can check on logfiles and data.

It also links to the Repeatability Plot and Published Position when finalized

** point out some columns ** 

## Coop vs. National

- Web page shows status of sites
- Data downloaded daily to compute position using metadata in NGS Database
- If data not present for solution, no daily position will be calculated.
- Data removed after 11 days

**Notes:**
Coop CORS vs. National CORS

Coop has a Web page that displays the status of the sites.  National has a link to a directory where text files can be viewed

Coop collects the data from the many sites using Java and Perl programs.  National uses individual Korn Shell scripts, but are in the process of changing over to the Coop CORS method

Coop CORS will not look for data older than 7 days.  If the are  no data for a particular site at 10 pm Eastern time.... no daily position.  National CORS will expend much effort to find missing data in order to archive it. The primary difference between the 2 is that you get National CORS data from the NGS server and you get Coop CORS data from the Coop member.

Coop removes data after 15 days, but it is available at the participants web site.  National keeps all data, but DOES decimated the data to 30 seconds after 30 days for archiving.  The CORS West collector in Boulder, CO is considering archiving raw data and rinex at its original rate.

## Coop CORS Data Collector

**Notes:**
Coop CORS Data Collector

This is a screen capture of the “All Sites” display of the Java program “coopCors.jar” written by Hong Chen.  It allows me easy access to the NGS Database.  With it, I enter the necessary information for the Perl program, Tasker, to use.

Tasker runs constantly looking for missing data for seven days.

At 10:00 PM Eastern time, a network solution is run on 
Coop CORS data from 7 days previous.

At the moment there are 122 Coop CORS sites.....

## Coop vs. National

- Web page shows status of sites
- Data downloaded daily to compute position using metadata in NGS Database
- If data not present for solution, no daily position will be calculated.
- Data removed after 11 days

**Notes:**
Coop CORS vs. National CORS

Coop has a Web page that displays the status of the sites.  National has a link to a directory where text files can be viewed

Coop collects the data from the many sites using Java and Perl programs.  National uses individual Korn Shell scripts, but are in the process of changing over to the Coop CORS method

Coop CORS will not look for data older than 7 days.  If the are  no data for a particular site at 10 pm Eastern time.... no daily position.  National CORS will expend much effort to find missing data in order to archive it. The primary difference between the 2 is that you get National CORS data from the NGS server and you get Coop CORS data from the Coop member.

Coop removes data after 15 days, but it is available at the participants web site.  National keeps all data, but DOES decimated the data to 30 seconds after 30 days for archiving.  The CORS West collector in Boulder, CO is considering archiving raw data and rinex at its original rate.

## Repeatability Plot

- Easy Drive in Austin, TX (EZAU)

**Notes:**

If no data present...... No Solution.

Such is the case with this site in Austin.  They thought they had the data in the correct location after they had made a change to the server, but this plot told us that something was wrong.   They then made the corrections so we could continue to collect data.

## Coop vs. National

- National CORS outnumbers Coop CORS by nearly 7 to 1
- Station Log and Data are the responsibility of the participant
- Not involved in multiyear solution, yet
- OPUS will not automatically select Coops

**Notes:**
Coop vs. National (cont.)

With Coop, the station log and data are the responsibility of the group supplying the data.  National keeps the station log and data in house
Coop is not involved in the multi-year solution to better determine velocities.... Yet.
OPUS will not look for a Coop CORS in its processing unless the user selects a Coop CORS site. 

## Baseline Plot Coop

**Notes:**
Baseline Plot

This is a plot of the baselines used for the solution on day 72
Sunday March 13.  

And here is the plot for the same day for National CORS...
** click next slide **

## 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

## Coop vs. National

- National CORS outnumbers Coop CORS by nearly 7 to 1
- Station Log and Data are the responsibility of the participant
- Not involved in multiyear solution, yet
- OPUS will not automatically select Coops

**Notes:**
Coop vs. National (cont.)

With Coop, the station log and data are the responsibility of the group supplying the data.  National keeps the station log and data in house
Coop is not involved in the multi-year solution to better determine velocities.... Yet.
OPUS will not look for a Coop CORS in its processing unless the user selects a Coop CORS site. 

## Cors Station Log Tool

## Coop vs. National

- National CORS outnumbers Coop CORS by nearly 7 to 1
- Station Log and Data are the responsibility of the participant
- Not involved in multiyear solution, yet
- OPUS will not automatically select Coops

**Notes:**
Coop vs. National (cont.)

With Coop, the station log and data are the responsibility of the group supplying the data.  National keeps the station log and data in house
Coop is not involved in the multi-year solution to better determine velocities.... Yet.
OPUS will not look for a Coop CORS in its processing unless the user selects a Coop CORS site. 

## Multi-Year Solution

**Notes:**
Multi – Year solution

The multi-year solution is the method used to compute velocities of the CORS sites.

At this time Coop CORS is not involved with the multi-year solution that National CORS runs.

There is a good possibility that we can produce a multi-year solution using the sinex files that are produced by the daily solution.

## Coop vs. National

- National CORS outnumbers Coop CORS by nearly 7 to 1
- Station Log and Data are the responsibility of the participant
- Not involved in multiyear solution, yet
- OPUS will not automatically select Coops

**Notes:**
Coop vs. National (cont.)

With Coop, the station log and data are the responsibility of the group supplying the data.  National keeps the station log and data in house
Coop is not involved in the multi-year solution to better determine velocities.... Yet.
OPUS will not look for a Coop CORS in its processing unless the user selects a Coop CORS site. 

## Select OPUS Sites

**Notes:**
Select OPUS Sites

Even though OPUS does not automatically select the Coop Sites for a solution, the user is given the opportunity to select them manually using the OPUS options page.

I will allow the Coop site into the option page only if the participant follows the NGS directory structure for rinex data and the data is “OPUS Worthy”.  Meaning that a good solution can be generated using those sites.