# Presentation: 501068

## OPUS  Online Positioning User Service

- Status & Future Prospects

**Neil Weston**
**NGS Convocation, 2005**
**Silver Spring, MD**

## OPUS – Current Status

- Accepts GPS Data in
- Native receiver format
- RINEX format (versions 2.0 & 2.1)
- Data Processing
- Uses three CORS stations
- Minimum of two hours of dual-frequency data
- Provides
- NAD83 & ITRF coordinates
- State plane coordinates
- UTM coordinates
- US National grid designator
- G-file, statistics, etc.

## OPUS Performance
Solution returned within a few minutes
Almost 12,000 solutions processed per month
Over 13,000 users

- Solution returned within a few minutes
- Almost 12,000 solutions processed per month
- Over 13,000 users

## OPUS Developments

- OPUS Database (OPUS-DB)
- 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 (Photos, descriptions)
- Submission review by user and NGS

## OPUS Rapid Static (OPUS-RS)

Rapid static solutions (10 – 15 minutes of data)
Accurate to few centimeters (1-2 horizontal, 2-4 vertical)
Network solution rather than individual baselines
Need more accurate ionospheric and tropospheric modeling

- Rapid static solutions (10 – 15 minutes of data)
- Accurate to few centimeters (1-2 horizontal, 2-4 vertical)
- Network solution rather than individual baselines
- Need more accurate ionospheric and tropospheric modeling

## OPUS Rapid Static (OPUS-RS) cont.

Uses RSGPS program instead of PAGES
	(based on OSU MPGPS program)
Uses P1 and P2 as well as L1 and L2 obs.
Resolves all ambiguities with LAMBDA
Geometry free linear combination used to determine DD ionospheric delays

- Uses RSGPS program instead of PAGES
- 	(based on OSU MPGPS program)
- Uses P1 and P2 as well as L1 and L2 obs.
- Resolves all ambiguities with LAMBDA
- Geometry free linear combination used to determine DD ionospheric delays

## 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

- 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 GIS

Compute a differential pseudo range 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

- Compute a differential pseudo range 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

## Questions ?

Suggestions !

- Suggestions !

**OPUS**