IWR6243: Profile Configuration Error

Tool/software:

Hi Team,

i am currently facing the following issue when i try to set the profile configuration of a cascaded IWR6243 Radar-System. I am trying to use the following Config Values:

profileId             = 0;         
pfVcoSelect           = 0b00;        // VCO1 75-60.75GHz
startFreqConst        = 1416742684;  // 57 GHz
idleTimeConst         = 10000;       // 100 us
adcStartTimeConst     = 1000;        // 10 us
rampEndTime           = 3000;        // 30 us
txOutPowerBackoffCode = 0;         
txPhaseShifter        = 0;
freqSlopeConst        = 1657;        // 60 MHz / us       
txStartTime           = 400;         // 4 us
numAdcSamples         = 64;
digOutSampleRate      = 4000;        // 4 MHz
hpfCornerFreq1        = 0;
hpfCornerFreq2        = 0;
rxGain                = 30;

Before using those Variables, i calculated if any of those values match with each other. From my calculation, those values should work:

• VCO1 should provide a possible slope bandwidth of 3.75 GHz (57-60.75 GHz)
• The Configured Start Freq Value Corresponds to a Start Freq of 57 GHz (because: 1416742682 * (2.7e9 / 2^26) Hz = 57e9 Hz)
• The Configured Slope Value Corresponds to a Slope of 60MHz / us (because: 1657 * (2.7e9 * 900 / 2^26) Hz= 60e6 Hz)
• The Configured Ramp End Time Value Corresponds to a Chirp Time of 30us (because: 3000 * 10 ns = 30000ns = 30us)
• The Bandwidth Occupied by the Slope should therefore not exceed 60MHz / us * 30us = 1.8 GHz

When i try to configure the IWR6243 with those Config Values, i get the Error Code 46, which indicates, that the Slope exceeds the given Frequency range. This would be caused by the Slope being to steep and/or the ramp end time to long. In this case the Frequency could slope up to 60.75 GHz and my calculation shows that the profile parameters are far from reaching this point. So why do i get this error?

Furthermore, i noticed something weird when trying to select to second VCO (60-64 GHz). When I select this VCO by:

pfVcoSelect = 0b10

I get the Error 36, which indicates that the Startfreq is out of Bound, when i try to set the Startfrequency somewhere in the given Frequency range. Only when i choose a startfreq between 57 and 60.75 it works, which should be out of the given Frequency Range.

What could cause this weird behavior?

I am using a custom configuration software, which uses the mmWave Link Library from the DFP Package. This Software is running on a Nvidia Jetson Nano. I previously could get a AWR2243 with this system. I also checked to configuration messages and they seem to be correct.

Sincerely,

Tim