IWR6843ISK-ODS: How to resolve and change the configure file?

Hello Jie,

Regarding your question about chirp equations, the application report "Programming Chirp Parameters in TI Radar Devices" will help you. It is linked below. Furthermore, we have mmwave trainings that may answer your questions.

App report: 

Training: 

Dear Sabeeh, 

Thanks for your quick reply and providing me with the document and trainint videos, which is really useful!

I would like to know how to know the "Number of chirp intervals in frame" or the "Frame time (total or active) " from a config file. For example, in the cfg file below. I want to know at least one of them from a given cfg file.

% Carrier frequency GHz 60
% Ramp Slope MHz/us 166
% Num ADC Samples 256
% ADC Sampling Rate Msps 12.5
% ADC Collection Time us 20.48
% Extra ramp time required (start time) us 3
% Chirp time (end time - start time) us 21
% Chirp duration (end time) us 24
% Sweep BW (useful) MHz 3399.68
% Total BW MHz 3984
% Max beat freq (80% of ADC sampling rate) MHz 10
% Max distance (80%) m 9.04
% Range resolution m 0.044
% Range resolution (meter per 1D-FFT bin) m/bin 0.044
%
% Inter-chirp duration us 7
% Number of chirp intervals in frame - 64
% Number of TX (TDM MIMO) 2
% Number of Tx elevation antennas 0
% Number of RX channels - 4
% Max umambiguous relative velocity kmph 72.58
% mileph 45.36
% Max extended relative velocity kmph 145.16
% mileph 90.73
% Frame time (total) ms 1.984
% Frame time (active) ms 1.536
% Range FFT size - 256
% Doppler FFT size - 32
% Radar data memory required KB 272
% Velocity resolution m/s 1.26
% Velocity resolution (m/s per 2D-FFT bin) m/s/bin 1.26
% Velocity Maximum m/s 20.16
% Extended Maximum Velocity m/s 40.32
% Maximum sweep accorss range bins range bin 0.91
%
sensorStop
flushCfg
dfeDataOutputMode 1
channelCfg 15 7 0
adcCfg 2 1
adcbufCfg -1 0 1 1 1
lowPower 0 0
profileCfg 0 60 7 3 24 0 0 166 1 256 12500 0 0 30
chirpCfg 0 0 0 0 0 0 0 1
chirpCfg 1 1 0 0 0 0 0 4
chirpCfg 2 2 0 0 0 0 0 2
frameCfg 0 2 32 0 100 1 0
guiMonitor -1 1 1 1 0 0 1
cfarCfg -1 0 2 8 4 3 0 15.0 0
cfarCfg -1 1 0 4 2 3 1 15.0 0
multiObjBeamForming -1 1 0.5
calibDcRangeSig -1 0 -5 8 256
clutterRemoval -1 0

compRangeBiasAndRxChanPhase 0.0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0
measureRangeBiasAndRxChanPhase 0 1. 0.2

aoaFovCfg -1 -90 90 -90 90
cfarFovCfg -1 0 0.25 9.0
cfarFovCfg -1 1 -20.16 20.16
extendedMaxVelocity -1 0

CQRxSatMonitor 0 3 4 63 0
CQSigImgMonitor 0 127 4
analogMonitor 0 0
lvdsStreamCfg -1 0 0 0
bpmCfg -1 0 0 0

sensorStart

Thanks a lot!

Regards,

Jie

I'm sorry, I don't understand your question. Are you trying to find these parameters in the CFG file?

Yes, I want to know which parameter in the CFG file can control "Number of chirp intervals in frame" or the "Frame time (total)".

In addition, I notice that the 5th value in "frameCfg" parameter represents frame periodicity, what the difference between frame periodicity and Frame time ?

Regards, 

Jie

Dear Sabeeh,

I want to confirm that whether the third argument in frameCfg can directly represent the "num of chirp intervals in frame"? I noticed that the value of "num of chirp intervals in frame" is 64 in comments while 32 at the third argument in frameCfg. Maybe I need to double the third argument in frameCfg to get the "num of chirp intervals in frame" value?

Regards,

Jie

Could you please show me from where you got this cfg file?

Sure, I found it at "...\mmwave_sdk_03_04_00_03\mmwave_sdk_03_04_00_03\packages\ti\demo\xwr68xx\mmw\profiles\profile_3d.cfg"

Regards,

Jie

Hi Sabeeh,

Thanks a lot for your quick reply!

The second argument for channelCfg is 7, which means tx1, tx2 and tx3 are enable. Why you said there were two TXs instead of three?

In addition, I am still confused about some parameters in the cfg file after reading the mmWave SDK user guide and the report - "Programming Chirp Parameters in TI Radar Devices". For example,  is there a file to introduce the CFAR algorithm CFAR-CA, CFAR-CASO, CFAR-CAGO, which may give me some idea on changing the 4th-6th and 8th arguments for cfarCfg as well as the arguments for CQRxSatMonitor and CQSigImgMonitor.

The reason why I want to understand every commands in cfg file is that I hope to figure out the question mentioned at the begining of this thread - why do the point clouds become sparser after sending a cfg file with a higher range resolution than the default cfg file?

Regards,

Jie