• State Resolved
  • Locked Locked
  • Replies 4 replies
  • Answers 1 answer
  • Subscribers 29 subscribers
  • Views 475 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.

Original question:

AWR1843BOOST: What is the difference and benefit of using VCO1 or VCO2

AWR1843BOOST: Bandwidth of USRR mode of Automotive Lab Demo MRR

Lei
Expert 2050 points
Part Number: AWR1843BOOST

In automotive lab demo mrr, the default setting of VCO is VCO1, therefore the frequency range should be 76~78GHz (bandwidth: 2GHz).

However, in the parameters settings of USRR mode: USRR20 and USRR30, it seems the bandwidth set for the ramp of chirp signal is larger than 2GHz. 

Can you please check if this is correct?

MODE DETECTION DISTANCE START_FREQ_GHZ RAMP_END_TIME_VAL(us) FREQ_SLOPE_MHZ_PER_US(mhz/us) bandwidth(mhz)
MRR 80 76.01 56 8 448
120 76.01 60 4 240
USRR 20 77.01 87.28 42 3665.76
30 77.01 44 56.25 2475
50 77.01 44 37.5 1650
  • 0
    TI__Guru*** 148974 points

    Hi,

    Your observation is correct.

    Please give me some time to look into this

    thank you

    Cesar

  • 0 in reply to Cesar
    TI__Guru*** 148974 points

    Hi,

    I have reviewed the documentation and other threads.

    The VCO selection is performed by internal firmware based on the starting frequency of the profile and the bandwidth.

    Sorry, the previous information was not correct. You don't need to configure the VCO used. Configuring the VCO used is only a debug feature not for production

    Please see Table 5.23, PF_VCO_SELECT

    C:\ti\mmwave_dfp_01_02_06_03\docs\mmWave-Radar-Interface-Control.pdf

    thank you

    Cesar

  • 0 in reply to Cesar
    Expert 2050 points

    Thank you. 

    So, for production and mrr demo, the sensor uses total bandwidth 76-81 GHz.

    Is it correct?

    Kind regards 

  • +1 in reply to Lei
    TI__Guru*** 148974 points

    This is not 100% correct.

    Based on the starting frequency of the chirp, VCO1 or VCO2 will be used.

    However since VCO1 covers 76-78GHz, it is not possible to have a chirp that starts at 76GHz and has 4GHz bandwidth.

    So the bandwith available is no 76-81Ghz, but 76-78Ghz and 77-81Ghz

    Thank you

    Cesar