AWR2944: DDM phase noise issue

Andy Yin

Part Number: AWR2944

Tool/software:

Hi,

Unequal interval DDM code and step frequency waveform，There are many phase noise burrs higher than the background noise. The false alarm rate is improved. As shown in the following figure. There was no significant improvement after the phase calibration was turned on.

7 months ago

0 Samhitha Bobba 7 months ago

TI__Mastermind 20670 points

Hi Andy,

Is the customer using their own processing chain? Can you also provide details on their step frequency waveform?

Regards,

Samhitha

0 Longtao Zhang 7 months ago in reply to Samhitha Bobba

Prodigy 140 points

Hi Samhitha Bobba,

We use own processing chain. The waveform is shown as below.

The center frequency is 76.5GHz. The frequency slope const is 106. The chirp period time is 51.55us（idel time 3.55us, ramp end time 48us, ADC start time 2.5us）. There are 256 chirps one frame. The sample frequency is 22Mhz. The step frequency is 1.16311MHz.

0 Samhitha Bobba 7 months ago in reply to Longtao Zhang

TI__Mastermind 20670 points

Hi Longtao,

As mentioned in the other E2E - (+) AWR2944: abnormal noise issue - Sensors forum - Sensors - TI E2E support forums, can you share the detection matrix to observe the behavior across the range bins. You can share the detection matrix in the form of *.mat file so that we can plot and analyse the data.

Can you also perform the same experiment with the TI DDM processing chain and compare the results?

Regards,

Samhitha

0 Longtao Zhang 7 months ago in reply to Samhitha Bobba

Prodigy 140 points

Hi Samhitha Bobba

I don't know how to share the detection matrix with you on E2E platform. I'll send Andy the detection matrix by E-mail, then Andy forward it to you.

0 Samhitha Bobba 7 months ago in reply to Longtao Zhang

TI__Mastermind 20670 points

Hi Longtao,

Let me check the detection matrix whenever Andy shares it with me.

Regards,

Samhitha

0 Andy Yin 7 months ago in reply to Samhitha Bobba

TI__Genius 9300 points

Samhitha,

sorry for the late, already forward u the data, pls help analysis and reply here, thanks.

Andy

0 Samhitha Bobba 7 months ago in reply to Andy Yin

TI__Mastermind 20670 points

Hi Longtao,

Are you performing phase shifter calibration? Is the behavior same at farther range bins or is this behavior is only observed at nearby range bins?

Also, can check the monitoring report of Tx phase shifters (enable monitoring)?

Regards,

Samhitha

0 Longtao Zhang 6 months ago in reply to Samhitha Bobba

Prodigy 140 points

Hi Samhitha Bobba,

I am performing pahse shifter calibration. If SNR is high enough, the behaviors are same at farther range bins and nearby range bins. We will conduct another experiment next month and we will send you the data and monitoring report.

Regards,

Longtao

0 Samhitha Bobba 6 months ago in reply to Longtao Zhang

TI__Mastermind 20670 points

Hi Longtao,

Sure, you can share the data whenever you perform the experiment. At the time you share the results, please share the phase shifter configuration for further analysis.

Regards,

Samhitha