MMWCAS-DSP-EVM: changing fft parameters

Sara Marina Salvador

Part Number: MMWCAS-DSP-EVM

I want to improve the range accuracy in the "cascade_radar_object_detect usecase" by applying zeropadding in the fft algorithm. Note that the zero-padding which is actually implemented is not what I need, as it is applied to reach the next power of two on the number of adc samples. For example, with 256 valid adc samples I want to compute the fft over 1024 samples (256 valid samples and 768 zeros). Is this possible? Which source files should I modify (I guess I need to modify fft parameterers and buffer dimensions).

Thank you,

Sara Salvador

over 4 years ago

0 Piyali Goswami over 4 years ago

TI__Mastermind 30235 points

Sara

The changes you would need to make are. Note this is not a configuration we support in the alg_fxn.

Function: void * AlgorithmFxn_RadarFftCreate(
AlgorithmLink_RadarProcessCreateParams *createParams,
AlgorithmLink_RadarProcessAlgCreateOpParams *opParams)

uint32_t numZeroPoints = AlgorithmFxn_RadarFftFindNextPowerOf2(
pRadarParams->radarWidth[i]) -
pRadarParams->radarWidth[i];
pObj->numPoints[chId][i] = pRadarParams->radarWidth[i]
+ (numZeroPoints % 8U) - 8U;

Function: Int32 AlgorithmFxn_RadarFftProcess(void *alg_handle,
System_Buffer *in_buf,
System_Buffer *out_buf)

nextPowerOf2 = AlgorithmFxn_RadarFftFindNextPowerOf2(
pObj->numPoints[chId][currProfile]);

----

pInArgs->numPointsZeroPadding = nextPowerOf2 -

pObj->numPoints[chId][currProfile];

in the file C:\PROCESSOR_SDK_VISION_03_07_00_00\vision_sdk\apps\src\rtos\radar\src\alg_plugins\alg_fxns\radarfft2\radarFft2.c

To give the exact number of Zeros you would like to add.

Thanks and Regards

Piyali

0 Sara Marina Salvador over 4 years ago in reply to Piyali Goswami

Intellectual 410 points

Hi Piyali,

I made the changes you suggested but when I run the demo I do not receive anything through ethernet. I will check if there is something which must be changed in the data transfer part and reduce the frame rate to have more time for doing calculations.

Sara

0 Piyali Goswami over 4 years ago in reply to Sara Marina Salvador

TI__Mastermind 30235 points

Sara

Can you please check if on the EVE core the following functions are being correctly executed?

AlgIvision_create

AlgIvision_process

These are defined in vision_sdk\apps\src\rtos\radar\src\alg_plugins\alg_fxns\radarfft2\radarFft_work.c

If these functions are failing due to incorrect parameters then you would need to debug what is the error returned and then tweak the parameters correctly to make sure these APIs are executing correctly.

Thanks and Regards

Piyali

0 Sara Marina Salvador over 4 years ago in reply to Piyali Goswami

Intellectual 410 points

Hi Piyali,

both AlgIvision_create and AlgIvision_process are executed correctly, they both return status = 0. And the execution goes on forever, I verified it by printing some messages on the command window. This makes me think that there is something wrong on the data transmission through ethernet.

Sara

0 Sara Marina Salvador over 4 years ago in reply to Piyali Goswami

Intellectual 410 points

Dear Piyali,

is it possible to have a conceptual map of all the structures adopted in the project?

Is it also possible to have a map of all the functions dependencies?

Thanks a lot,

Sara

0 Piyali Goswami over 4 years ago in reply to Sara Marina Salvador

TI__Mastermind 30235 points

Sara,

I would not suspect the Ethernet functions as yet. I would suggest first to check the output of the EVE function and plot it in MATLAB or Excel surface plots to check whether the output is coming correctly.

Thanks and Regards

Piyali

0 Piyali Goswami over 4 years ago in reply to Sara Marina Salvador

TI__Mastermind 30235 points

Sara,

The API guide may be the closest to what you are looking for. For the mapping and function dependency, you would need to spend some time with the code and understand which API calls what. You may want to refer to tutorial videos which would give you a high level idea on the SDK structure.

https://training.ti.com/node/1139569?context=1137175-1139569

https://training.ti.com/node/1139570?context=1137175-1139570

Thanks and Regards

Piyali