Afternoon folks:
I'm working on an application in which the IWR1443 will be powered-up every once in a while to perform a single measurement (likely a single frame) and then will be shut down (the IWR1443 will be controlled by a master processor). It will likely be running for much less than 100 ms each time. Since the power budget is limited, I plan to perform a full calibration at the factory so that the device can do partial calibrations in the field to reduce power usage (will load calibration from QSPI flash and perform any appropriate boot time calibrations per TI labs and suggestions).
Since the IWR1443's operation will be extremely intermittent, Scheduling of Periodic Runtime Calibration and Monitoring via the RfInit API is not appropriate to this application . With respect to the "Self-Calibration in TI's mmWave Radar Devices" SPARACF4A document, which of the calibrations should be performed in the field due to temperature changes? Text on page 10 of the document states,
"Every CALIBRATION_PERIODICITY, the processor reads the temperature and performs a calibration update if
needed. This update is done only if the temperature deviates by ±10 degrees compared to the temperature when
the last calibration was done. LO Distribution calibration updates are done only if the temperature deviates by
±20 degrees from the temperature at last update."
It is clear from this text that the LO Distribution calibration should be performed if the temperature deviates by 20 degrees. However, it also infers that other calibrations should be performed if the temperature deviates by more than 10 degrees. Given that, which calibrations should be repeated if the temperature deviates by more than 10 degrees?
In general, I'd like the IWR1443 to operate as follows. A full calibration will be performed at the factory with data stored in QSPI flash. Every time the IWR1443 is brought up by the master processor in the field it will load the factory cal data from QSPI flash and perform any appropriate boot time calibrations. The master processor will keep track of temperature changes and will command the IWR1443 to perform additional calibrations when it determines that a temperature change has exceeded thresholds. In that particular situation, I need to know which calibrations need to be performed in the field based on temperature deltas.
Thanks! -Michael