Question about the configuration File Cfg of radar AWR1843 in OOB demo

Mohamed Naceur Hassine

Intellectual 460 points

Other Parts Discussed in Thread: AWR1843

Hi,

I'm using AWR1843 with OOB demo and I have question about a parameter in the file cfg of the radar.

I'm want to ask about the Threshold scale in Cfarcfg :

Exemple :

cfarCfg -1 0 2 8 4 3 0 15 1
cfarCfg -1 1 0 4 2 3 1 15 1

From the documentation I found that the " Threshold scale in dB using float representation. This is used in conjuntion with the noise sum divisor (say x). the CUT comparison for log input is: CUT > (Threshold scale converted from dB to Q8) + (noise sum / 2^x)"

I would like to know what's the threshold scale and how it is calculated?

What is the divisor of the noise sum (say x ) and what does it correspond to in the OOB code?

What is the noise sum and what does it correspond to in the OOB code?

"The threshold scale is converted from dB to Q8"? what is Q8? why and how is it converted?

Best,

Ben Hassine

over 2 years ago

0 Pradipta Bandyopadhyay over 2 years ago

TI__Mastermind 33265 points

Hi Ben,

We will need some time to check on this query. Kindly allow us some time to check on this and get back to you.

Thanks,

Pradipta.

0 Mohamed Naceur Hassine over 2 years ago in reply to Pradipta Bandyopadhyay

Intellectual 460 points

Hi Pradipta,

Thank you for your reply. I will wait for your return.

Ben Hassine

+1 Kaushik Gowda over 2 years ago in reply to Mohamed Naceur Hassine

TI__Mastermind 20605 points

Hi Ben,

Threshold scale is the scaled value of against which the Cell under test is compared with to establish whether the CUT is a valid detection or not. The threhold will be obtained from the CFAR window and will be scaled before the comparison with the CUT.

The 2^x component will perform shifts in the noise such that the threshold and noise are in the same relative scale or level. For what it corresponds to in the SDK, you can obtain this from the source code in the SDK.

The noise sum is the noise average obtained in a given pass of a CFAR window slide. The same can be used to correct the threshold such that the comparison takes place for values only above the noise floor.

The CFAR config takes input in dB format (log base 10). This needs to be converted into the base of log2 as the HWA takes input in this format. For more info on this, you can refer to the HWA userguide.

Regards,

Kaushik

0 Mohamed Naceur Hassine over 2 years ago in reply to Kaushik Gowda

Intellectual 460 points

Hi Kaushik,

Thank you for your response, it helped me a lot.

Regards,

Ben Hassine

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Question about the configuration File Cfg of radar AWR1843 in OOB demo