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BOOSTXL-AOA: Map the received IQ sample timestep to the protocol timestep

Hidden ChenYu
Prodigy 30 points

Part Number: BOOSTXL-AOA

I try to understand the mapping from the received waveform to the protocol time frames and met some problem

My understanding is the sample is 8 sample per 1us (although I leave the `aoa_sample_rate: 1` as default  in `rtls_aoa_iq_with_rtls_util_export_into_csv.py`), so for the guard period 4us it has 8*4=32 sample, but it cannot explain the  the waveform turn into sine-wave at 115th but not (4+8)*8= 96th sample. Note that I keep antenna one only ` "aoa_sampling_control": int('0x10', 16)  ` all the way.

Also I plot more packages, there are lot of packages does not match the protocol frame

My question are:

(1), what is the IQ sample rate, it looks like it is 4M in first plot, but the code is `aoa_sample_rate: 1` as default  in `rtls_aoa_iq_with_rtls_util_export_into_csv.py`

(2) why different package has different samples, if it is 4M or 1M sample rate, we should have 160*4 = 640 or 160 samples, I know channel hopping may make the number vary a bit, but I do not see many 640 or 160 samples, the number of samples per package varies a lot (see histogram attached below).

(3), why different packages have different waveforms, I expect them more or less the same.

Best 

Hidden