IWR1843BOOST: AWR1843AOPEVM:Azimuth FFT size: n-point FFT

Ayush Shetty

Part Number: IWR1843BOOST

Hello Forum,

I wanted correct my understanding,To find N-point FFT for any given lab,the value of n depends on adc sample.If adc sample equals 64 then my value of n is 2 power 6 so N=6.

Is this logic correct to find Azimuth FFT size

Does the same logic apply for elevation FFT size.

Any refernce to this undertanding is aperciated

Warm regards

Ayush Shetty

over 2 years ago

0 zigang Yang over 2 years ago

TI__Mastermind 40335 points

HI, Ayush:

Which parameter you are talking about here? Is a input configuration parameter or internal parameter? can you be more specific?

Best,

Zigang

0 Ayush Shetty over 2 years ago in reply to zigang Yang

Prodigy 80 points

We give Number of ADC sample as parmater in the radar configuration.

0 Ayush Shetty over 2 years ago in reply to Ayush Shetty

Prodigy 80 points

You can share your understanding to find the N ,for N-point FFT for Azimuth and Elevation.

+1 zigang Yang over 2 years ago in reply to Ayush Shetty

TI__Mastermind 40335 points

Hi, Ayush:

In the range FFT, FFT size is the power 2 round up to the number of ADC samples. For example if numADCSample = 64, then rangeFFTSize is also 64. But if numADCSample = 50, then rangeFFTSize is also 64.

params->rangeFftSize = mathUtils_pow2roundup(params->ADCBufData.dataProperty.numAdcSamples);

The same rule applied to Doppler FFT, angle FFT.

Regarding n = 6, probably you are talking about FFT engine inside HWA, the fftsize inside hwaParamCfg is in log2 format.

hwaParamCfg.accelModeArgs.fftMode.fftSize = mathUtils_ceilLog2(pDPParams->rangeFftSize);

Best,

Zigang

0 Ayush Shetty over 1 year ago in reply to zigang Yang

Prodigy 80 points

Hello Zigang,

This gives a lot of clarity,One last question,What is the maximum FFT size limit for TI radars in general?

Warm regards

Ayush Shetty

+1 zigang Yang over 1 year ago in reply to Ayush Shetty

TI__Mastermind 40335 points

HI, there:

In the FFT engine inside radar HWA, the FFT sizes supported are all powers of 2 until 1024, for example, FFT sizes of 2, 4, 8, 16, … 512 and 1024 are supported.

Note that FFT stitching is a feature that enables large FFT sizes, specifically, 2048 and 4096, using a two- step process.

Best,

Zigang

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IWR1843BOOST: AWR1843AOPEVM:Azimuth FFT size: n-point FFT