Revision(s) Affected:

IWR1642 ES1.0 and IWR1642 ES2.0

Description:

When the synthesizer (chirp) frequency monitor is enabled and the synthesizer chirp is around 76.8 GHz, the frequency error can be as high as 500 kHz due to coupling between the monitor and the synthesizer. The RF frequencies impacted are 500Mhz around 76.8Ghz (76.8 ± 0.5 GHz).

Implication: Increased nonlinearity in the chirp can lead to up to 20 dB degradation in the noise floor surrounding large objects. This leads to potential loss of dynamic range when large and small objects are present simultaneously.

Workaround(s):

1. Disable the synthesizer frequency monitor during profiles where the LO crosses 76.8 ± 0.5 GHz.
2. Use non-functional chirps to detect nonlinearities (instead of high instantaneous frequency errors) in the synthesizer by inserting dummy chirps (where RX data is not used) after functional chirps (where RX data is consumed).