05 - LabSat 3 Recording and Replaying

Media/Memory

LabSat 3 units use an SSD Drive or SD cards to record and playback GNSS data.

We recommend that you use an SSD Drive (such as the LS03WSSD-1TB) to record and replay GNSS data. This is to make sure that you get the best and most stable data transfer possible. 

LabSat 3 Triple Constellation Variant

If you need to use an SD card, it is important to note that due to the high-speed transfer rates and data transfer methods used by the LabSat 3 Triple Constellation variant, specific SD cards are required, such as SanDisk Extreme Pro 32 GB (RLACS352). 

Notes:

• SD cards used with Racelogic products must be formatted as FAT32. LabSat 3 can format cards and HDD units to FAT32 with the optimum configuration for high-speed recording.  When LabSat 3 formats a card or HDD unit, it will also carry out a performance test to determine whether or not the media can sustain the required bandwidth. If it determines that the card is unsuitable it will display a warning message. 
• You can purchase these SSD Drives and SD cards directly from Racelogic.

Antenna

For record-capable systems, the LabSat will be supplied with a magnetic mounting GNSS antenna. The antenna is an active device with approximately 28 dB of gain.  The LabSat provides a 2.85 V DC bias for antenna power on the centre pin of the RF IN connector. It is also possible to use third-party antennas providing they are compatible with the 2.85 V bias.  If connecting LabSat to an antenna which requires a higher bias voltage (e.g. 12 V), the antenna bias must be supplied by the user and an appropriate DC block (such as DCB from http://gpsnetworking.com/attenuators.asp) must be inserted at the LabSat 3 RF IN connector to avoid damage to the LabSat.

Frequency Bands

There are several GNSS systems currently in operation or in a test phase. These operate on 3 main frequency bands.

Depending on the model, LabSat 3 will have 1, 2 or 3 RF channels. This allows recording of 1, 2 or 3 frequency bands.

For example, a 2-constellation LabSat 3 may record the band containing GPS L1/Galileo E1 and the band containing GLONASS L1 simultaneously. 

You can configure the recording of the desired constellations in the CONSTELLATION menu. You can select up to three of the desired constellation groups (depending on the version you have). If you only select one constellation, an additional option for 2-bit will be available to allow 2-bit quantised recording for the selected constellation.

When you have configured the constellations, you can exit the menu and press the REC button to begin recording. The unit will create a new file each time it starts recording. The file name will correspond to the selected constellations. 

For example, if you have selected GPS and GLONASS for recording, the file will be named GPSGLO_nnn where nnn is a number that increments with each new recording.  You can get further details of the LS3 file format on request from Racelogic.

If you press the OK button while the unit is recording, it will switch the display to show satellite levels for either GPS or GLONASS satellites. In this display mode, you can use the UP/DOWN buttons to toggle between GPS or GLONASS constellations. The BeiDou constellation is not currently supported by the internal monitor, but you can still record and replay BeiDou B1 signals.

Battery Life

To maximise battery life during recording, LabSat 3 has a power-save mode enabled by default. You can change this setting in the setup menu. The power-save mode recognises when the unit is running from battery power and will dim the display backlight and power down the internal GPS/GLONASS monitor after 30 seconds of user inactivity. 

If you are recording from passive antennas, such as the Maxtenna M1516HCT-SMA GPS/GLONASS antenna, having the power-save mode enabled will also provide the highest possible sensitivity by ensuring that unused modules in LabSat 3 are switched off.