Satellite Visibility
This section contains a satellite map and over time plots each tracked satellites orbital path. GPS satellites and their trails are in blue, and GLONASS satellites and their trails are in red. The present location of the satellite is represented by the marker 
, and the Satellite Vehicle Identifier is located adjacent to it.
The top of the satellite map marked as 0o degrees is the bearing in relation to North. The 90o, 180o and 270o markings represent East, South and West respectively. The concentric circles on the satellite map represent the angle above the horizon. Therefore; the centre of the map represents the space directly above the antenna looking up into orbit.
Satellite Signal Reception
The satellite signal reception section is used to display the real-time strength of satellites being tracked. Any satellite that is showing an excess of 35dBHz with good health reporting in the health almanac, and which are not below the antenna mask angle will be used for time and position calculations. These are shown as solid bars. Satellites that do not meet these criteria will be shown as a faded coloured bar.
- Blue Bars indicated GPS satellites
- Purple/Red bars indicate GLONASS satellites
The number above each bar indicates the signal strength (dB Hz) of the satellite to the GNSS receiver.
The number below each bar indicates the Space Vehicle number. The space vehicle number is a unique identifier of each GPS or GLONASS satellite.
If you select a bar in the satellite signal reception section the SV number and marker in the satellite visibility map will be highlighted
Location
The location section is used to provide information regarding the store position reported by the GNSS receiver. The position is displayed in degrees, minutes and milli-minutes, and the elevation is displayed in metres.
Status
The status section of the GNSS tab provides real-time information on the status of the clock.
The following are a list of valid messages that may appear
|
Antenna Current Low |
The antenna circuit drain is low (typically under 3mA). This could be caused by poor connections, or if the connected antenna has a lower current drain specification or if a component in the antenna system is providing power to the antenna and therefore the clock is not seeing a connected load. |
|
Antenna Current High |
The antenna circuit drain is high (typically over 100mA). This is caused by a short in the antenna circuit or by moisture ingress in the circuit, or if the antenna connected has a higher current drain specification |
|
Antenna Ok |
Antenna system is connected and is perceived to be operating normally. |
|
GNSS position Hold |
Almanac has been downloaded. Position is known and the GNSS is providing its most accurate time. |
|
Doing Fixes |
Synced to one or more satellites and now calculating positioning and timing solution. Downloading Almanac |
|
Acquiring |
Searching for satellites |
|
Bad Geometry |
Insufficient satellite distribution to calculate and accurate position |
Settings
In the GNSS settings for the live view, there are many configuration options to allow optimal GNSS coverage.
Mask Angle
This is the angle (in degrees) from the horizontal plane (horizon) below which satellites signals will not be used in calculating time and position. Increasing the mask angle will avoid errors caused by ionosphere, troposphere and multipath effects. however, this will also limit the number of satellites being tracked. The default setting is 5 degrees. The configurable range is 0 to 90 degree.
When the mask angle is modified, the satellite map is dynamically updated with grey shading which indicates the masked section of the horizon.
Cable Delay
The Cable delay setting can be used to calibrate the delay between the antenna and the time server. To optimize the precision of the output signals at the clock output terminals, enter a value in this field corresponding to approximately 4ns per 1m of antenna cable. For example, if the antenna cable is 30m long, the "cable delay" should be configured to 120ns.
Constellation
As GNSS cover multiple constellations the Tekron configuration tool software allows you to choose which constellations (or combination of constellations) you wish to acquire satellites from.
Currently, the configuration software supports:
- GPS
- GLONASS
- GPS + GLONASS
Anti-Jamming Mode
The anti-jamming mode setting will help to mitigate jamming or spoofing attempts by preventing the tracking of only a single satellite. When this option has selected a minimum of 2 satellites are required to maintain synchronisation. when this option has not been checked, one satellite operation is allowed, which helps maintain synchronisation on sites where there is poor satellite coverage.
Mobile GNSS
"Mobile GPS/GNSS" box should be checked when the clocks are installed in moving platforms(such as moving vehicles or vessels). When this option has been checked, the position and timing solution is continuously updated.
Minimum SN Value
The minimum SN value setting allows the user to configure the minimum signal to noise ratio that a satellite must have before it can be used for timing.
For example, if the SN value is 35dB then any satellite with a signal to noise ratio below 35dB will not be used for timing.
Reset "GPS" or "GNSS" button
The reset GNSS or GPS button is used to reset the GNSS or GPS receiver, clear the receiver’s memory and discard the stored almanac.