98 jun 01 updated 98 sep 23

What's Happening?

This is an exciting year, 1998. On a firm foundation of basic knowledge, we are patiently building the test and measurement facilities to evaluate equipment and optimize results as we look forward to the implementation of the Spectra Precision vision: Integrated Surveying™. Indeed, our fascination is with what might be termed: Integrated Development, encompassing GIS to the field.

We have been beta-testing new software forthcoming from ESRI, called the Tracking Analyst, that we find to be a valuable tool for better observing, understanding, using, managing, and applying GPS technology. Direct, real-time output from the GPS receiver appears on the ArcView screen, epoch-by-epoch. A database is simultaneously fed enabling continued analysis after the fact. While we now have the ultimate tool set for for post-processing, GeoGenius 1.6, earlier this summer we conducted some observations with RT. It is very satisfying to have the resource, Erla. The foundation for good real-time GPS is a good reference position. We have established several mechanisms for controlled study of GPS performance, enabling optimization of the result from field campaigns. While we have yet to achieve final optimizations, here are some preliminary reports.

With Spectra Precision (SP) RTK, we have observed 95% of epochs falling in a circle of radius 2.0cm, 80% within 1.1cm. Using the more neutral (and correspondingly less efficient) RTCM 2.1 protocol, we observed 95% epochs within a 4.8cm radius and 80% within 3.0cm. There was also an 8mm bias between the two epicenters. This is an initial trial and further optimizations are anticipated to yield slightly better results.

  80 95 99 %epochs
RTK 1.1 2.0 3.5 cm radius
RTCM 3.0 4.8 7.3 cm radius

These tests were using short baselines. Our next endeavor will push the baseline to 30 miles. We have observed radio communication from our roof to the outer reaches of I-275 North and East. Another requirement for good Real-Time GPS is good radio engineering. We now have our radio license and the analytic tools to master the radio component. We expect more complete trials and results using all the final products during October.

Using the Ashtech Reliance, single-frequency receiver and StarLink BEACON Receiver, we have recorded about 80% of epochs within a 1m radius using the St. Louis BEACON SIGNAL. Before we had the tools to identify the source of the BEACON, we tried to hide from the signal by locating the antenna in the foothills of Dayton, KY along the river--but never lost the signal! Since then, we have learned that the Louisville CORS was up, but went down with the rain, forcing a rebuild of the site that was completed in August.

If you have been noticing the ads, Spectra Precision is putting the pieces together for a solution with unprecedented scope: from field to instrument to data collector to desktop to final design, and then back to the field--enabling the design model to directly drive the earth-moving machines. GPS is properly a foundation for SP, both for its absolute, world-wide common coordinate system, and for its equally common measuring ability. When comprehensive satellite positioning technology is coupled with superior survey tools represented by Geodimeter, the result is unparalleled economy based on consistency. And we can expect the software to make it easy. Better, easier, lower cost.

In May, we exhibited at two GIS conferences: CAGIS sponsored the MidWest ESRI User Group Meeting at Convention Center, and the KY GIS Conference was held in Somerset, KY. Then in June we exhibited at the GITA IKO Regional Conference at Kings Island. At each conference, John presented a session entitled USING CORS: PUBLIC ACCESS GIS. In demonstrating the BEACON signal, we had to fall back on St. Louis which we have found to be useful except when there is a significant rain/storm pattern in between. Louisville, now in place, is a strong, clear and stable signal, consistent with our early observation.

We are soon to schedule a new seminar showing the final result of all these beta pieces falling into finished form. Epochal !!

Until then, back to work!