Precise thinking  

Technical Reports About Waypoint Software Products and Their Applications

Precise Point Positioning

Inertial Explorer

RTKNav/RtStatic

  • Tracking Sonobuoy's with RTKNav (PDF - 113KB)
  • This report describes how RTKNav was used to process data from GPS equiped sonobuoys in the calibration of underwater sonar systems. This report is provided here with the kind permission of Gregory J. Baker of the Defense Research Establishment and Hermes Electronics Inc.

  • Monitoring Movement of the San Andreas Fault with RtStatic (PDF - 111KB)
  • This report describes describes a 252 day test of RtStatic using two IGS stations on opposite sides of the San Andreas fault.

  • Slope Deformation Monitoring with RTKNav / RtStatic (PDF - 628KB)
  • RtStatic uses Waypoint's GrafNav processing receiver to provide Fixed Static solutions in near real-time. Simultaneously, the standard kinematic receiver processes the same data in real-time to monitor fast moving events.

Kinematic Ambiguity Resolution

Batch Processing

  • Kinematic Batch Processing Accuracies of One Data Set at Varying Baseline Distances using CORS Stations in GrafNav Version 7.50 (PDF - 209KB)
  • This report shows obtainable accuracies for one data set when batch processing using CORS base station data. In each run, three CORS stations are used at average baseline lengths of 130 km, 545 km and 1,270 km. Results are compared with the processing results from three locally established base stations which had an average baseline length of 14 km during the survey. Batch processing results are presented both with Waypoint's older style of batch processing as well as the new style available in version 7.50. The new method of batch processing uses all of the data simultaneously in one Kalman filter.

  • SCOUT, OPUS, GrafNet and GIPSY - a Comparison (PDF - 108KB)
  • This report compares the free email/ftp based static processing services of SCOUT, OPUS, and GIPSY. Batch results from GrafNet are also compared.

ION Papers

  • Reliable Single Frequency Dual Antenna Processing System for Marine Dredging Applications (PDF - 547KB)
  • GPS real-time kinematic (RTK) has been utilized for harbor dredging applications for a number of years. Such applications require both accurate position and heading in order to obtain the location of the dredging vessel implements. The method described here involves mounting two remote GPS antennae on the vessel, denoted R1 and R2. Their distance separation is pre-calibrated and will remain constant with vessel dynamics. A base station (M) is also employed on shore. The vessel's position is obtained by solving for the vector M-R1 or M-R2, while vessel azimuth is computed from R1-R2. Optimal accuracies are obtained using on-the-fly (OTF) techniques.

  • Tracking the relative motion of four space payloads launched from a sub-orbital NASA rocket (PDF - 157KB)
  • This report describes the use of moving baseline software in tracking post-mission, the relative trajectories of 4 Ashtec G12 HDMA GPS receivers attached to payloads jettisoned from a Black Brant XII rocket.

Low Cost Receivers

High End Receivers

Moving Baselines

Long Baselines

  • Static Baseline Accuracies as a Function of Baseline Length, Observation Time and the Effect of using the Precise Ephemeris (PDF - 112KB)
  • Examined in this report are static baseline accuracies for baseline lengths of 5, 20, 40, 60, 200, 300, 400, 500, 700, 800, 900 and 1000 km. Each baseline is processed with 1, 3, 6, 12 and 24 hours of data with both the broadcast and precise ephemeris in order to establish:

    1. When the precise ephemeris begins to make a measurable difference
    2. What level of accuracy to expect for given baseline lengths and occupation times
    3. How much data should be collected before little or no improvement is seen in the convergence of the solution
  • SCOUT, OPUS, GrafNet and GIPSY - a Comparison (PDF - 107KB)
  • This report compares the free email/ftp based static processing services of SCOUT, OPUS, and GIPSY. Batch results from GrafNet are also compared.

  • 1000 KM Baseline Determination in Static and Kinematic Mode. (PDF - 233KB)
  • This report tests the accuracy of GrafNav in determining 1000 KM baselines between CORS stations. The static results obtained by GrafNav are compared against results obtained by JPL's GIPSY program as obtained through their internet service. Lastly this report investigates GrafNav's ability to process 1000 KM baselines in kinematic mode. Although, this is not recommended, it is of interest to examine the results obtained.

  • Establishing Local GPS Base Stations using GrafNet and a Network of Long Baselines (PDF - 381KB)
  • The purpose of this report is to demonstrate how to use GrafNet to establish a local base station by using a network of long baselines. This is often necessary when a DGPS survey is being performed in an area with no local control.

  • Kazakh - Northern Block, Single Frequency Long Baseline Adjustment (PDF - 320KB)
  • The following is a report on a long baseline adjustment for a GPS survey performed in Kazakhstan by Stuart Engineering and Surveying (SESL) of Calgary. Apart from results of the survey, detailed information is provided on access to IGS RINEX data files, CORS precise ephemeris files and the NIMA EGM96 worldwide geoid model.

  • Accuracy Tests on Kinematic Long Distance Baselines (PDF - 434KB)
  • These tests use four United States NGS CORS stations with baseline lengths of 460km, 1180km, and 2640km. We performed this test to determine the feasibility of utilizing kinematic carrier phase on long baselines.

Airborne Surveys

  • Using CORS/IGS Base Stations for Airborne (PDF - 327KB)
  • This report discusses the accuracy of using CORS/IGS as base stations for Airborne data.

  • GPS Airborne Accuracies (PDF - 34KB)
  • Photogrammetry is used to map large areas of the ground using overlapping photographs. Instead of placing control points on the ground, the airborne GPS positions each photograph accurately by acting like a control point for each photo.

Research Reports by Waypoint Consulting

The goal of the following reports is not to promote any of our software packages, but rather to inform users regarding topics of interest in GPS. All reports are in PDF format.

Disclaimer: These reports reflect the views of Waypoint Consulting. Users should conduct their own tests should the results be of interest in some application.