MMWCAS-RF-EVM: longer capture time and lower sample rate on mmW cascade board

Hello Jet,

Can you let us know your profile, chirp and frame configuration? What are the number of frames you're configuring for master and slave devices? (i.e nframes_master/slave?)

Also, what is the value of 'num_frames_to_capture` in `Cacade_Caputure.lua`?

Regards,

Ishita

Hi Ishita Kochar

My setting is  'num_frames_to_capture = 0  # default setting` in `Cacade_Caputure.lua`

My scripts is attached here, again my aim is longer collection time and lower sample rate (the current .bin is too huge and slow)

I may forget where I change the code, do you mind send me the orginal version of code  `Cacade_Caputure.lua` and  `Cascade_Configuration_MIMO.lua`

Best

Jet

Hello Jet,

You can increase the number of chirps in a frame or the number of frames to increase the capture time. (I can see you increased the frame count to 200 for this).

Regarding lower bin size, just reduce the number of ADC samples to your desired value. This will reduce the bin size at that amount. 

"local adc_samples" is the concerned variable in the MIMO script. By default, the value is 256.

Also, here are the fresh example scripts :

Cascade_Configuration_MIMO_Capture.zip

Regards,

Ishita

Hello Jet,

Jianyuan Yu said:

They are at the .lua files attached in the link.

What are you referring to here? If you're mentioning about your lua scripts, I did take a look.

Regards,

Ishita

Thanks Ishita Kochar Cesar

I tried your method, the adc_samples does help to reduce the data size, while the number of frames(nframes_master  nframes_slave) and chirp per frame (nchirp_loops) does NOT work ... 

It is true the data size increase if I increase the nframes_master or nchirp_loops.   The data collection time is read from the log windows, correct me if I take the `recording time` wrong.

Best 

Jet

thanks, that was a bit confusing... Ishita Kochar Cesar Casas

However, I still not believe my current setting is correct, I plan to collect to 60 second, ignore the confusing output time gap, I feel like the time gap I press the GUI button "Run!" to WinSCP window is definitely smaller than 60 seconds.

I even write two line my own script in the `Cascade_Capture.lua` to record current time. Both right after  line 95 ` WriteToLog("Starting Frame Trigger sequence ... \n","blue")   `  and  line 133  `WriteToLog("Capture sequence completed ... \n",'"blue")`, I write `print(os.date("%H:%M:%S"))`, and in this way I record time capture begin and ends, still it looks it is still around 2 seconds.

also I attached the .lua script below

Does the mmW board or anyone really did long-time data collection?

Best

Jet

Jet

Hello Jianyuan, 

As I had said, "capture_time" does not control the actual duration of capture.

From your configuration, I can see the your programmed frame periodicity as 100ms and number of frames as 10. This leads to just 1 second of total capture time and since there is still a statement of "RSTD.Sleep(capture_time)" in the script which is programmed to 2 seconds, you're getting the output logs in mmWave studio at a interval of 2 seconds. 

Please note, the actual capture duration depends only on the configured frame time and number of frames. 

Regards,

Ishita

Thanks a lot.

So, did you mean change these lines:

(1). local Inter_Frame_Interval      =   100    -- ms    => e.g. local Inter_Frame_Interval      =   200 

(2). 

local nframes_master = 10 -- Number of Frames for Master
local nframes_slave = 10 -- Number of Frames for Slaves

=> 

local nframes_master = 20 -- Number of Frames for Master
local nframes_slave = 20 -- Number of Frames for Slaves

Again, I have change the local nframes_master, local nframes_slave to 60 and I did not see any longer capture time, after I click run button, in less than 10 seconds, the mmW Studio pop up the WinSCP windows, which indicate the capture time is pretty short.

great, it works, thanks a lot.

To sum up:

(1) change local nframes_master and local nframes_slave  in `Cascade_Config_MIMO.lua`

(2) according change capture_time in 'Cascade_Capture.lua'