DW1000 test mode CW waveform

Wireless Connectivity Ultra-Wideband
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Hi,

I had the chance to check the waveform of a DWM1000 module.
In upfront, I did following checks:

  • Reset DWM100
  • Setup registers as per DW1000 users manual 2.10 chapter 8.1.1 (page 189), the only difference is that I used values for CH3 instead of CH5

Here’s my plot of DWM1000 which I expect to be factory calibrated (isn’t it?)

DWM1000_CH3_CW_20190326
DWM1000_CH3_CW_20190326703×396 39.7 KB

So, the same dip in the middle of band and slightly different center freq compared to my previous post with DW1000 and custom PCB. I put marker to the nominal center which is 4492.8MHz but I can consider this deviation as missing calibration of my spectrum.

I also took a screenshot with more span, in this one it is 200MHz:

DWM1000_CH3_CW_20190326_200MHz
DWM1000_CH3_CW_20190326_200MHz699×398 36.7 KB

This is still the DWM1000 and I also see the harmonics in ± 38.4MHz which makes me suspicious of intermodulation with clock signal.

I’m unsure if this is what I should see but I can confirm that this DWM1000 tag works perfectly in non-test conditions.
I’m a bit lost…
Do I have measurement errors? Or should anything else configured for test mode than description mentioned in users manual above?
Anyone from DW, do you have guys some reference plots I could compare my one?

Any thoughts or hints are much appreciated.

Thanks,
d