GPS Server Screenshots

The GPS Server connects to a single GPS device attached to the local COM: port or to a remote instance of the same GPS server using telnet (TCP/IP). 

The map displays the given antenna position as well as the current position reported by the GPS unit using the symbols and labels defined here.
Note: currently no map data available.

The GPS Server provides its data to an optionally limited number of clients using the built-in telnet- and web-server.

Clients connecting via telnet receive the original data stream from the GPS unit or may even filter out NMEA sentences required.

• Telnet:  send * or a list of NMEA identifiers (eg. GPGSV) ending with a <CR>.
  Send EXIT<CR> to end the session .

Web clients receive the current NMEA sentences in XML format or the corresponding HTML page dynamicalls generated by the GPS server using a simple XSLT template. 

• XML/XSL Output
• HTML Output

Current NMEA senteces are displayed in the GPS monitor window.

Status messages and server connections are displayed below.

Depending on the GPS unit features, internal data such as the board temperature of the GPS 25 unit by Garmin may be displayed.

The GPS Server optionally sets the system time and date with regard to summer time settings.

The most important data for positioning is displayed here (if provided by the GPS unit). Signal strength is shown graphically and numerically. 

In sky-view, you can monitor the current position of the GPS satellites in view from your position.

Check the tool-tip (not visible on the screen shot) for azimut, elevation and signal strength for each satellite.

This histogram shows which satellites are operational now and how often they are used to calculate the current position.

In the upper histogram all satellites are listed (ID01-ID31). After running for months, all satellites passed except 12.

How many satellites could be used to calculate the position? The lower digram shows, that for 39% of the servers uptime, 9 satellites were available.

The quality of the positioning heavily depends on the antenna position and a clear view. The next screenshots illustrates this.

This figure shows the tracks of each satellite and plots the signal strength: the brighter the splash, the stronger the signal.

The anteanna of this GPS unit is mounted on the roof of a house with a clear view but the top of the roof lies in south western direction.

The black hole demonstrates the fact, that the GPS satellites don't pass in northern directions viewed from this position.

Here is the position data.

Optionally, this map (if any available, no free source implemted yet) would be reloaded  if the position changes significantly.

How accurate is GPS? The ground plot shows the track of the current position calculated by the GPS unit.

The antenna position given by the user lies in the center of this picture. The current position (blue) and the mean position (red) are plotted.

The red oval shows the mean position and its dimensions correspond to the statistical variance of the current position plot.