ITK and Dual Antenna Receivers
Frequently asked questions about ITK on dual antenna receivers such as the OEM 7720 and PwrPak 7D.
Q1: Can interference be detected and logged from the second antenna?
A1: Yes. By default, interference detection is on for the first antenna but not the second. To configure detection on the second antenna, use an ITDETECTCONFIG_1 command. Once this is done, interference detection results for the second antenna will be logged in ITDETECTSTATUS_1.
Q2: Can the RF spectrum be logged by the second antenna?
Q3: Can filters be applied on the secondary antenna? Related, are filters automatically applied to both antennas?
A3: Yes, filters can be applied to the secondary antenna, however, they are not automatically applied to both antennas. A user can use ITPROGFILTCONFIG_1 or ITBANDPASSCONFIG_1 to configure a filter on a signal path on the secondary antenna, and ITFILTTABLE_1 to see the configured filters. The available filters are in ITBANDPASSBANK_1 and ITPROGFILTBANK_1.
Q4: Does the ITWARNINGCONFIG command apply to both antennas?
A4: Yes, ITWARNINGCONFIG is applied to both antennas. There is no ITWARNINGCONFIG_1 command.
Q5: Which ITK logs or commands allow an _1 extension?
A5: Here are the commands:
- ITDETECTCONFIG, ITDETECTCONFIG_1
- ITSPECTRALANALYSIS, ITSPECTRALANALYSIS_1
- ITBANDPASSCONFIG, ITBANDPASSCONFIG_1
- ITPROGFILTCONFIG, ITPROGFILTCONFIG_1
- ITFRONTENDMODE, ITFRONTENDMODE_1
Here are the logs:
Here is an example of how to use dual antenna ITK:
At startup, send this command to detect interference on both antennas, rather than just the first antenna (note that ITDETECTCONFIG ALL is a default command):
To view the detection status from both antennas, log:
LOG ITDETECTSTATUSB ONCHANGED
LOG ITDETECTSTATUSB_1 ONCHANGED
To view the spectrum from the primary antenna, commands like these could be used:
ITSPECTRALANALYSIS PREDECIMATION GPSL1 1000 8K 5 2
LOG ITPSDFINALB ONNEW
To view the spectrum from the secondary antenna, commands like these could be used. Note that only one spectrum can be collected at a time.
ITSPECTRALANALYSIS_1 PREDECIMATION GPSL1 1000 8K 5 2
LOG ITPSDFINALB_1 ONNEW
If interference is identified that should be mitigated on the primary antenna, use commands such as this to view allowable filters, choose a filter, and confirm it is configured:
ITBANDPASSCONFIG BEIDOUB1 ENABLE 1555
ITPROGFILTCONFIG GPSL1 PF0 ENABLE NOTCHFILTER 1580 1
Similarly, on the secondary antenna these commands can be used. Note that the allowable filters vary based on the channel configuration.
ITBANDPASSCONFIG_1 BEIDOUB1 ENABLE 1555
ITPROGFILTCONFIG_1 GPSL1 PF1 ENABLE NOTCHFILTER 1580 1
To change to HDR mode on all RF paths for both antennas, use these commands:
ITFRONTENDMODE L1 HDR
ITFRONTENDMODE L2 HDR
ITFRONTENDMODE_1 L1 HDR
ITFRONTENDMODE_1 L2 HDR
To log the interference detection spectrum from both antennas, enter:
LOG ITPSDDETECTB ONNEW
LOG ITPSDDETECTB_1 ONNEW
Please contact NovAtel Support for remaining questions or technical issues concerning ITK on dual antenna receivers, or visit the NovAtel Support page for additional resources.