User Guide
Table Of Contents
- Contents
- 1 Preface
- 2 Features
- 3 Getting Started
- 4 Concept and Philosophy
- 5 u-center Menus and Windows
- 5.1 Main frame and toolbars
- 5.2 Views and windows
- 6 NTRIP
- 7 Google Earth server
- 8 Tools
- 9 How To
- 10 Troubleshooting
- 11 Related Documents
- 12 Revision History
u-center-User Guide
UBX-13005250 - R18
Production Information 4 Concept and Philosophy
Page 10 of 67
4 Concept and Philosophy
Understanding the basic concept behind u-center is important in order to get the highest benefit out of this
powerful evaluation software. Figure 5 depicts the architecture of the software. The program gets a data stream
from either a communication port or a log file and splits this stream into protocol messages. From the messages,
relevant parameters are extracted and inserted into the current dataset of the database that is used by the display
and analysis features of the application.
In the current dataset, statistical values of the parameters are calculated. Average, minimum, maximum and
standard deviation are calculated for most parameters. If the available messages do not provide a parameter, u-
center tries to calculate the parameter from the ones that are available. For example if velocity-north and velocity-
east are available, u-center calculates the speed over ground and course over ground, unless this data is already
available in other messages.
Figure 5: Engine Architecture
When a new epoch (change in time) is detected, the current dataset is stored as history in the database. The
database used is Sqlite and the name of the database file is ucenter.db. It can be found in the directory defined
with the environment variable named %LOCALAPPDATA%\u-blox. Every instance of u-center creates this file
with a unique timestamp added to its name. The file is not deleted after u-center closes, so the database can be
used for post-processing using the standard SQL language. However, to avoid leaving large amounts of historical
database files lying around, when u-center starts it tries to delete all database files that are currently not in use.
The database size may be adjusted. If the size is exceeded u-center keeps only the latest datasets and the oldest
ones are removed. Refer to Database limitations for the details.
Very long recordings may decrease performance of u-center.