AWR1642: Bin2Mat Code question in Application Note "xWR1xxx ADC Raw Data Capture" based on AWR1642 complex mode using TSW1400

Zhenyuan zhang

Part Number: AWR1642

Now I am working with AWR1642 and TSW1400EVM and MMDEVpack.

I have read the application note "xWR1xxx ADC Raw Data Capture.pdf" and analyzed matlab code. However, I have a problem about the code for AWR1642.

I use complex 1X mode. According to the application note, the bin format is shown,

In the code:

LVDS(1,:) = adcData(1,:) + sqrt(-1)*adcData(2,:); 
    if numRX > 1
        LVDS(2,:) = adcData(3,:) + sqrt(-1)*adcData(4,:); 
        temp_LVDS_data_1 =  LVDS
        LVDS = reshape([LVDS(1,:); LVDS(2,:)], size(LVDS(1,:),1), []);%%% end

For example, the value of temp_LVDS_data_1 is (only for one chirp)

Each value in temp_LVDS_data_1 is complex.

Then if we run this line:

 LVDS = reshape([LVDS(1,:); LVDS(2,:)], size(LVDS(1,:),1), [])
LVDS can be described as shown:

over 7 years ago

0 Zhenyuan zhang over 7 years ago

Intellectual 280 points

So, I feel confused.

Thanks a lot!

0 Justin Curewitz over 7 years ago

TI__Mastermind 28055 points

Hi Zhenyuan,

I want to clarify that you are confused due to the call to reshape. The call to reshape interleaves the values, resulting in the second LVDS array that you have described. This is not due to the data from the Radar Studio, this is due to normal Matlab behavior.

There is online Matlab documentation for the reshape function. The Matlab forums also have a lot of helpful answers.

Best of luck,

Justin

0 Zhenyuan zhang over 7 years ago in reply to Justin Curewitz

Intellectual 280 points

Thank you for your reminding. I'll check the code right now.

0 Zhenyuan zhang over 7 years ago in reply to Justin Curewitz

Intellectual 280 points

Hi Justin Curewitz

I've checked the code. For real data, I've no question. But for complex data, I'm still confused. This pic is the analytic process

I think there may be some wrong when understand the bin format,as shown

0 Justin Curewitz over 7 years ago in reply to Zhenyuan zhang

TI__Mastermind 28055 points

Hi Zhenyuan,

When the Matlab code from the document reads the .bin file, it interleaves the samples. This happens before the line of code you are looking at. So the data in the "LVDS" matrix will not be in the format described in the document as it has already been reformatted.

Regards,
Justin

0 Zhenyuan zhang over 7 years ago in reply to Justin Curewitz

Intellectual 280 points

Hi Justin,

Thank you for your reply.

I think I havn't understood your meaning. Could you help me to explain how the matlab code in "xWR1xxx ADC Raw Data Capture" interleaves the samples clearly? According the code, it is right for Read Data bin format, as shown in Figure 11.

But, Why does the code can interleaves the complex samples, as shown in figure 12?

I will conduct some experiments to validate my thought.

Thanks a lot!

Best Regards

0 Zhenyuan zhang over 7 years ago in reply to Justin Curewitz

Intellectual 280 points

Hi Justin

I have validated the code under real data only and complex 1x data, respectively.

For real data, there is no problem.

For complex 1 data, I divided data into real component and image component, plot time-domain and frequency-domain figures, respectively. They can get the same right range measurement.

So, I doubt that the actual bin data are not arranged as described in Figure 12.

By the way, I doubt that there are some mistakes in Figure 9.

Best Wishes！

0 Justin Curewitz over 7 years ago in reply to Zhenyuan zhang

TI__Mastermind 28055 points

Hi Hi Zhenyuan,
Do you have any more questions?
Regards,
Justin

0 Zhenyuan zhang over 7 years ago in reply to Justin Curewitz

Intellectual 280 points

Now, I don't have any more questions. if you are available, please check figure 12. Thanks a lot

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AWR1642: Bin2Mat Code question in Application Note "xWR1xxx ADC Raw Data Capture" based on AWR1642 complex mode using TSW1400