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2.1 GrafNav, GrafNav Lite and GrafNav / GrafNet Static Overview
GravNav
GrafNav is a full-featured kinematic and static GNSS post-processing package that uses a proprietary GPS and GLONASS processing engine. It supports both single and multi-baseline (MB) processing. GrafNav supports most single and dual frequency commercial and OEM receivers. See Table 2 on Page 29 for more information.
GrafNav seamlessly switches from static to kinematic processing and has a fixed static solution for static initialization of short or medium length baselines that are 0 to 30 km. A float static solution is available for long and/or noisy baselines. Kinematic Ambiguity Resolution (KAR) allows you to start in kinematic mode and fix otherwise unrecoverable cycle slips. GrafNav’s ionospheric processing improves accuracies for dual frequency users.
This chapter describes how to get started with GrafNav and goes through each menu of its interface. Step-by-step instructions for first-time users are also included.
GrafNav Lite and GrafNav / GrafNet Static
This chapter also describes the features of GrafNav Lite and GrafNav Static.
GrafNav Lite is a simplified version of GrafNav. It contains all of the conversion and logging utilities, but only supports processing intervals of 1 second or lower. GrafNav Lite achieves accuracies of 5 to 20 cm even though it only includes float static initialization and does not support KAR.
GrafNav / GrafNet Static provides the same processing features as GrafNav / GrafNet, but only for static baselines.
See Table 1 on Page 27 for a capability comparison between GrafNav, GrafNav Lite and GrafNav Static.
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2.2 Start a Project with GrafNav
How to install GrafNav
1.See Section 1.2.2, on Page 24 for installation instructions.
How to convert data
1.Select File | Convert | Raw GPS to GPB to access the converter.
2.Navigate to the directory that contains the data.
3.Select Auto | Add All to auto-detect GPS formats.
4.If you want to change the conversion options, click on Options or Global Options to set the rover to kinematic mode.
How to download service data
1.Select Tools | Download Service Data.
2.Click on the Add Closest tab and type in the approximate position of the project area. To compute the average position from the remote GPB file and set the times and file path on the first tab, select Position from GPB and choose the converted GPB file.
3.A list of the nearest service stations appears. Highlight those of interest, and click Add Selected.
4.On the Download tab, enter the time and date of the survey as well as the directory where the files are to be saved.
Before you start a project in GrafNav, you need to verify installation, convert data and download any required data.
Install Software
Verify that the installation was successful by ensuring that you have a Waypoint GPS program group on your computer. If this program group is not there, see Chapter 1 on Page 23 for installation instructions.
Convert Data
To be processed, raw GPS data files have to be converted into Waypoint’s GPB format, including raw data from Waypoint’s data-logger program. Instructions on how to convert these files are in the shaded box.
The GPBView utility can be used to switch between static and kinematic mode. See Chapter 8 on Page 221 for a complete description of the Convert utility.
Download Service Data
If no data was logged from a reference station, you have the option of downloading free GPS data from the Internet. See the shaded box for instructions on how to add the closest service station to your project area.
A reference station can also be added directly from a list. See Section 2.8.12, on Page 140 for these instructions as well as a complete description of the
Download utility.
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