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RACELOGIC Support Centre

Create - SatGen 4

This page covers the Create tab in the SatGen 4 software and its features and functionalities. It includes the options involved in the creation of the various possible outfput files.

The Create Tab

Click on the Create tab to configure and create your output file. You will see the following: 

Create Default - LabSat 3 Wideband - Hidden directory.png

Output 
Format

Select the format of your output file, which is the LabSat product you wish to replay the scenario on. 

You have the following options: 

  • LabSat 1
  • LabSat 2
  • LabSat 3
  • LabSat Realtime
  • LabSat 3 Wideband 
  • NMEA

Create - format_LabSat 3 Wideband_cropped.png

Information

Click on the information icon to the right of the selected format to see relevant information for your chosen LabSat product, such as the Data rate, Sample rate, Bandwidth and Frequency. 

Create - Format - Information - LabSat 3 Wideband.png

Directory
This is the location where you wish to save the scenario file. SatGen 4 will use the SatGen OutputFiles folder by default, but you can change the location by clicking on the  button next to the directory name. This will open the Windows File Explorer, where you can navigate to the required save location.  Directory_framed.png
File name

This is where you enter the name for your scenario file. SatGen 4 will use New Scenario_xxxx as the default name. 

If you have entered a file name but want to revert to the automatic naming system, you can click on the Reset button behind the file name. 

File name_framed.png
Signals

This area will display the signals that are available. They will change depending on the set output format and the SatGen 4 variant you are using. 

Click on the signals you wish to include in your file.

Selected options will be highlighted in blue. 

Signals.png
Quantisation

This area gives you the option to select between 1-, 2- or 3-bit quantisation.

Note: The available options will depend on the set output format and the SatGen 4 variant you are using. 

quantisation.png
Signal to Noise Ratio

You can use the attenuation tick box to enable or disable the attenuation.

When it is enabled, you have the option to adjust it between 0 and -15 dB.

Note: You can read more about the Signal-to-noise ratio in SatGen 4 here.

Signal to noise ratio.png
Create File
Click on the Create File button to make SatGen 4 generate your scenario file and save it in your chosen directory. The file will be available in the queue where you can see the progress of the creation.  Create file button.png

Note: The generation of scenario files takes a lot of resources, and your computer may struggle to perform other tasks while SatGen generates these files. If you need to create multiple scenario files, we recommend that you use the Add to Queue button to save your file in the queue while you configure your other scenarios. You can then choose to resume the file generation when you are ready. 

Add to Queue
Click on the Add to Queue button to make SatGen 4 send the scenario file to the queue and pause the file generation. This lets you resume the file generation process at a suitable time.     Add to queue button.png

Note: The generation of scenario files takes a lot of resources, and your computer may struggle to perform other tasks while SatGen generates these files.

Real Time Creation

The SatGen software can generate a live signal stream to a LabSat Realtime unit that can convert the RF data from digital to analogue with less than 1 second’s latency.

Real Time is an output format in SatGen 4. There are two variations of this feature:

  • Current Time: You can create a live signal output for the current time.
  • User Time: You can create a live signal output for a specified time and date.

Once you have specified your desired route, you can proceed to create the scenario.

 

  1. Select LabSat Realtime as your Format
Create - format_cropped.png
  1. Select the Mode you wish to use, Real Time (Current Time) or Real Time (User Time) 

Note:

  • Real Time - Current Time will always start the simulation at the next whole minute.
  • Real Time - User Time will start the simulation instantly.
LabSat RT - mode_cropped.png
  1. Select the Reference Clock you wish to use from the following options:
  • OXCO
  • TCXO
  • External 10MHz
  • External 16.368MHz
Reference clock_cropped.png
  1. You can also choose 1- or 2-bit quantisation and whether you want to attenuate the signal-to-noise ratio. 
quantisation and attenuation.png
  1. Click the Simulate button to confirm the output format. This will open a Live Output tab next to the Create tab.

Note: When you want to run real-time simulations, we recommend that you disable all background activity in Windows, pause Windows Updates, etc.

Simulate button.png
Live Output - Mode
Auto

This mode will use the total number of satellites as restricted to the value in the Total Satellites setting. 

If a buffer under-run occurs, (indicating that the computing power required to simulate that many satellites exceeds the capabilities of the computer), SatGen 4 will reduce the total number of satellites by 1. 

This makes it safer to run a real-time simulation on a slower machine, as the number of satellites will keep dropping one by one until there are no more buffer under-runs and the simulation is stable. 

That final number of satellites is then remembered between sessions, to avoid buffer under-runs the next time you run a real-time simulation. 

Note: The simulated satellites are chosen by an algorithm that promoting the satellites that are going to stay in view longer.

Mode - Auto_cropped.png
Constellation 

The number of satellites is limited separately for each constellation.  You can, for example, select 8 GPS satellites and 5 Galileo satellites.

Constellation Satellite number

You can select the number of satellites you wish to simulate from each available constellation. The available constellations will depend on your system. 

Note: The simulated satellites are chosen by an algorithm that promoting the satellites that are going to stay in view longer.

Mode - constellation_cropped.png
Total

This mode will use the total number of satellites as restricted to the value in the Total Satellites setting. 

If a buffer under-run occurs, (indicating that the computing power required to simulate that many satellites exceeds the capabilities of the computer), SatGen 4 will attempt to simulate the specified number of satellites even if the machine is not capable of sustaining it.

Note: The simulated satellites are chosen by an algorithm that promoting the satellites that are going to stay in view longer.

Mode - total_cropped.png
No Limit

The number of satellites is not limited in any way.  All satellites in view will be simulated whether the PC can process the simulation or not.

Mode - No limit_cropped.png
Manual

You can select the satellites you wish to simulate manually from the list of visible satellites.

Unlike in the Constellation, Auto and Total modes, where you select the number of satellites but not which satellites in each available constellation, you have full control over which satellites are simulated in Manual mode. 

Mode - manual_cropped.png
Total Satellites

This setting defines the maximum number of satellites SatGen can use in the simulation.

Use the up and down arrows to adjust the number of satellites. 

Reset

Click the Reset button to set the number of Total Satellites to the default value of 999.

Total satellites.png
Stop Button

Click the Stop button to stop the simulation.

Stop button.png
Attenuation Sliders

You can use the attenuation sliders to add attenuation to the individual satellites. Alternatively, you can link the attenuation sliders to apply the same level of attenuation to the entire constellation.

Note: Due to the Automatic Gain Control always amplifying the signal to fully utilise the 1- or 2-bit output range, reducing the level of all satellites will not affect the signal. You can reduce the level of 1 or 2 satellites in relation to the others, but the total signal power will always remain constant. 

Attenuation sliders.png
Status Indicator

You will also see a new status indicator on the Toolbar. 

Live output - toolbar.png

The status indicator will display yellow when the simulation first starts and the time is being synchronised. It will display green when live signals are being transmitted. If too many satellites are present the status will briefly display red to symbolise an overload and reduce the number of satellites until it is able to successfully transmit again.

A counter will be displayed in the status to make it easy to see how many times the software has encountered an overload during the simulation.

SatGen Wideband

SatGen 4 can create wideband signals in the upper and lower L band and will take advantage of the LabSat 3 Wideband unit's ability to read RF data at up to 95 MB/s. SatGen 4 can create the following signals in 1-, 2- or 3-bit I & Q Format:

  • GPS L1C/A
  • L1P
  • L1M
  • L2C
  • L2P
  • L2M
  • L5
  • Galileo E1 B/C
  • E5a
  • E5b
  • E6 B/C
  • GLONASS L1OF
  • L2OF
  • BeiDou B1I
  • B2I
  • B3l
  • NAVIC L5 SPS
  • S SPS

You can find the full signal description for each signal here

NMEA 

Mode: To File 

Directory

This is the location that you wish to save the scenario file in. SatGen 4 will use the SatGen OutputFiles folder by default, but you can change the location by clicking on the  button next to the directory name. This will open the Windows File Explorer, where you can navigate to the required location. 

File name

This is where you enter the name for your scenario file. SatGen 4 will use New Scenario_xxxx as the default name. 

If you have entered a file name but want to revert to the automatic naming system, you can click on the Reset button behind the file name. 

Include VTG

Tick this box to include the VTG message in your output file. 

NMEA - File.png
Mode: RS232 Stream

COM Port

Select the COM port you wish to use for the output stream.

Baud Rate (B/s)

Set the required baud rate for your output stream.

Include VTG

Tick this box to include the VTG message in your output stream. 

Playback

Output Rate (Hz)

Select the output rate you wish to use:

Output Speed

Select the output speed you wish to use: 

  • 1
  • 2
  • 5
  • 10
  • 20
  • 50
  • 100
  • 0.1x
  • 0.25x
  • 0.5x
  • 1x
  • 1.5x
  • 2x
  • 5x
  • 10x

Repeat

Tick this box to make the stream loop.

NMEA RS232.png
Live Output

RS232NMEA-Live_output-full screen_framed.png

 

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