Average GNSS

The Average GNSS tab allows the user to define how the software will handle the averaging of multiple measurements to the same point.

• Point Averaging Mode: Indicate the method by which the Point Average will be approached:
  • From Raw Data: With this option, the complete set of enabled measurements will be used in the processing of the averaged results.
  • GNSSAnalysis: With this option (a forerunner to the more verbose SurvNET Least Squares routine), the analysis approach deals with one Point ID at a time, and works if multiple measurements were taken on that Point ID. The method, however, is designed for a field procedure of distinct single point measurements using Store Point (again, storing the same Point ID on successive measurements) typically at intervals over a period of time. By using this procedure, greater point positional certainty can be obtained through statistical analysis.

    Preconditions to GNSS Analysis: The following preconditions must be available for GNSS Analysis:

    1. The GNSS Receiver itself must offer the option to store GNSS vectors and make this available to Carlson Software.
    2. Both the Job File AND the associated Raw File (of the same name) must be on the same data directory. In other words, if you just copied a CRD file to a PC without the associated RW5 file, GNSS Analysis will not work.
    3. The data in the Raw File has to contain RMS values, DOP values and vector data, stored based on enabling the Store GPS Accuracy in Raw File option.
    4. There should be a significant time delay between the measurements (e.g. +120 minutes).
• Beep on rejected measurements: When enabled, SurvPC will provide an audible alert for measurements that are outside established Tolerances (subject to the main Audible Settings.
• Log Average Observations: When enabled, the individual measurements associated collected by Store Points - Average will be recorded.
• Automatically accept average results: When enabled, the results of a Point Average will be automatically saved.
• SurvNet duplicate point tag: Indicate a character that is used within a point description that indicates the measured point is another instance of a previously measured point:

   1,5000.00,5000.00,100.00,bs
   2,5500.00,5000.00,101.00,op
   3,5322.73,5657.24,102.36,fp
   ...
  13,5322.76,5657.22,102.34,fp =3

• Coordinate Match Tolerance: Indicate an allowable distance that should be used to determine if points within the tolerance can be evaluated as duplicated.
• 2D/3D: Indicate if the Coordinate Match Tolerance value should be treated as a horizontal 2D distance or sloped 3D distance.