Revision(s) Affected:

IWR1642 ES1.0 and ES2.0

Description:

External interference present on the RX or TX pins, during the period of the device calibration at RfInit, can lead to degraded accuracy or errors in the calibration results. If the interference changes its level while these calibrations are actively running, the calibration algorithm may interpret this as a change in signal power, leading to incorrect convergence. This applies to boot-time PD, Rx IQ mismatch calibration, Rx gain calibration, Tx power calibration, and phase-shifter calibration. It also impacts run-time Tx output power calibration in CLPC mode.

Workaround(s):

Workaround #1:

The incident power detector in the TX output power detector, along with the absolute level of the PA loopback used during the PA loopback monitors, are insensitive to this, and they can be used to check that the calibrations converged correctly. Calibration can be re-run if large interference was observed.

Workaround #2:

Another workaround is to save the boot time calibrations at production (done in a clean environment without interference) and during operation, the calibrations can be restored. For the runtime Tx output power calibrations, OLPC mode can be used instead of the CLPC mode.