Novatel OM-20000122 Variable Lever Arm, Enabling L-Band, NovAtel Correct with TerraStar

Chapter 3 SPAN-CPT Operation

3.8Variable Lever Arm

The variable lever arm concept arose to support applications in which the IMU is no longer rigidly fixed to the vehicle, but rather on a gimballed mount. This creates an issue where the input lever arm offsets to the GNSS antenna are no longer correct, because the IMU can rotate on its mount, while the antenna remains fixed.

The use of the variable lever arm functionality requires that the device to which the IMU is attached be able to send its gimbal rotation angles back to SPAN. These angles are used to re-calculate the lever arm at the rate that they are received. SPAN is also able to output a gimballed solution at the rate the gimbal angles are received. Refer to SPAN on OEM6 Firmware Reference Manual (OM-20000144) for details.

3.9Enabling L-Band

L-Band equipped receivers can achieve sub-metre position accuracy using correction data received from geostationary satellites. To use the L-Band corrections, an L-Band-capable receiver model and antenna are required (refer to our web site www.novatel.com/products/gnss-antennas for information on NovAtel L-Band-capable antennas).

For more information on L-Band positioning, refer to:

•NovAtel Application Notes: APN-061 NovAtel CORRECT with TerraStar, APN-062 NovAtel CORRECT with Veripos (service dependent) or APN-051 Positioning Modes of Operation available from www.novatel.com/support/search/items/Application%20Note

•the OEM6 Family Firmware Reference Manual (OM-20000129) for log/command details

•visit www.novatel.com/support

•visit www.novatel.com/products/novatel-correct

3.9.1NovAtel CORRECT™ with TerraStar™

A subscription is required to use the TerraStar service. To obtain a subscription, contact your local NovAtel sales representative or visit www.novatel.com/products/novatel-correct. The receiver’s TerraStar Product Activation Code (PAC) or the NovAtel product serial number (PSN) is needed to obtain a subscription. To obtain the receiver-specific PAC, enter the following command:

log terrastarinfo

This log displays the PAC in the first field following the log header and also displays the status of your subscription.

To activate a subscription, the receiver must be powered and tracking an L-Band TerraStar satellite prior to the planned activation time. Use the ASSIGNLBANDBEAM command to configure the receiver to track the TerraStar satellite.

To confirm tracking of an L-Band signal, log the L-Band tracking status information by entering the following command:

log lbandtrackstata

If receiving TerraStar service, the sixth field following the header (tracking status word) of the LBANDTRACKSTAT log will be 00c2, as shown in the following example:

#LBANDTRACKSTATA,COM1,0,73.5,FINESTEERING, 1769,328196.000,00000000, 29fd,12602;1,"98W",1539902500,1200,974c,00c2,0,-316.186,43.842, 4.3840,61.920,1088,2,2, 138176,79,0.0001*3e43cb7d

The latest services and coverage can be obtained from www.terrastar.net. For additional information on TerraStar activation, contact NovAtel Customer Service at www.novatel.com/ support or download the APN-061 NovAtel CORRECT with TerraStar from: www.novatel.com/support/search/items/Application%20Note.

34 SPAN-CPT User Manual Rev 8