• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 30 subscribers
  • Views 478 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

AWR6843: When one chirp occurs, ADC data is obtained

juncheng Wu
Prodigy 30 points
Part Number: AWR6843

Hello,TI engineers,

I had obtained the ADC Data through CAN communication and now I have some question about the memory browser in 0x51000000

I turned off the FFT by setting the parameters (fftEn=0, windowEn=0) in rangeprochwa.c. Subsequently, I use this configuration to validate the obtained data as ADC.

RadarFormat = DPIF_RADARCUBE_FORMAT_2

ADCsample = 64

Chirp            =8

Antenna       = 12

In this configuration, the ADC data appears to be satisfactory, as I utilized MATLAB to compute the range FFT, and the amplitude increased in the correct bin

show my result

Subsequently, i change the config as :

ADCsample = 64

Chirp            =1  << Change this

Antenna       = 12

In this configuration, I observed that the memory browser (0x51000000) would appear zeros in the sequence

it seems that the TX3 didn't work.

And I also extend the rampEndTime but i seems have same phenomenon

I would like to know if I can set the chirp to 1 and whether it would be considered abnormal in this situation (chirp = 1) ?

  • 0
    TI__Genius 13376 points

    Hey Juncheng,

    I would highly recommend reviewing the following document: <MMWAVE_SDK3_VER>/packages/ti/datapath/dpu/rangeproc/docs/doxygen/html/dpu_rangehwa.html. This document breaks down many of the considerations that need to be taken into account when modifying or adjusting the range processing chain.

    It seems like the most likely cause of this issue is due to the HWA's ping-pong buffers. The ping/pong scheme implemented in the rangeProcHWA DPU, requires that the number of chirps per frame divided by the number of Tx antennas should be an even number. This equation also applies for calculating the number of chirps for Doppler computation purposes. It is also a requirement that the number of chirps per frame be a multiple of two due to the ping/pong buffers and EDMA. To satisfy both conditions, the number of chirps per frame must be a factor of 6 when using 3 Tx antennas.

    Let us know if you have any other questions.

    Regards,

    Kristien

  • 0 in reply to Kristien Everett
    Prodigy 30 points

    Thanks!  
    Now I get why this happens!
    I tried a simple test with chirp set to 3, and it matched what I expected !!

    Sincerely,
    JcWu

  • 0 in reply to juncheng Wu
    TI__Genius 13376 points

    I'm glad I was able to help! If you have any further questions, please post them to a separate thread.

    Regards,

    Kristien