About JSON format BGT60TR13

[vderoc]

How can I know this parameters

"num_chirps_per_frame": 128,
"num_samples_per_chirp": 32,

from this JSON

{
    "device_config": {
        "fmcw_scene": {
            "rx_antennas": [1, 2, 3],
            "tx_antennas": [1],
            "tx_power_level": 30,
            "if_gain_dB": 30,
            "range_resolution_m": 0.15,
            "max_range_m": 10,
            "max_speed_m_s": 5,
            "speed_resolution_m_s": 0.2,
            "frame_repetition_time_s": 0.1
        }
    }
}

In RDK SDK Documentation say that:

"The number of ADC samples per chirp is computed from max_range_m. The number of chirps per frame is computed from speed_resolution_m_s. The pulse repetition time (PRT) is computed from max_speed_m_s."

There is a ny way to calculate these parameters?

When I capture from RADAR GUI the data says:

"## Data_Format_Enum_Def = {DATA_REAL = 0, DATA_COMPLEX = 1, DATA_COMPLEX_INTERLEAVED = 2}"


"# Modulation_Type_Enum = 1"

This means that data is complex, it is so?

And if yes, when I compile app_recorder and configure with a JSON like this, where is the DATA FORMAT:

{
"device_config": {
"fmcw_scene": {
"rx_antennas": [1,2,3],
"tx_antennas": [1],
"tx_power_level": 31,
"if_gain_dB": 33,
"range_resolution_m": 0.031,
"max_range_m": 1.6,
"max_speed_m_s": 4.864,
"speed_resolution_m_s": 1.216,
"frame_repetition_time_s": 0.005
}
}
}

Thanks.

[vderoc]

The first question related to know these parameters from JSON file:

"num_chirps_per_frame": 128,
"num_samples_per_chirp": 32,

 I can answer myself,  I can use "bgt60-configurator-cli" and with this generate de .h file and in that file are those parameters

maybe is not the correct way but is one way.

I stilll need to undertand data format, if  when I use app_recorder it comes in REAL or COMPLEX and of course if is sended as Radar SDK says.

Thanks

[Siddharth_H · Accepted solution]

Hey @vderoc ,

1) The formulae to calculate number of samples, number of chirps and PRT are,

You can find these in the RDK documentation inside the Introduction to Radar section.

Yes, using bgt60-configurator-cli is also one of the ways to know the configuration parameters from the json file, you can also manually calculate them with the formulae I mentioned above. 

2) Data_Format_Enum_Def is just the definition for Data_Format_Enum, value of this enum is mentioned in the below lines which is 0 for BGT60TR13C, meaning the data is Real.

In the image above, you can see that line 4 just defines what enum values mean, and line 21 specifies that the data is real. Also, data format of app_recorder and Radar Fusion GUI are the same.

Thank you,

Siddharth

[Siddharth_H · Accepted solution]

Yes, using bgt60-configurator-cli is also one of the ways to know the configuration parameters from the json file, you can also manually calculate them with the formulae I mentioned above. 

[vderoc]

Hi, Siddhart

Point one is clear thanks.

But second point and need some clarification:

I understood what you say line 4 is definition and line 21 spicifies the type of data, but when I use app_recorder, with a JSON like this.

Where is the data_format specified?

How I should know that data returned by app_record is in real or complex?

{
"device_config": {
"fmcw_scene": {
"rx_antennas": [1,2,3],
"tx_antennas": [1],
"tx_power_level": 31,
"if_gain_dB": 33,
"range_resolution_m": 0.031,
"max_range_m": 1.6,
"max_speed_m_s": 4.864,
"speed_resolution_m_s": 1.216,
"frame_repetition_time_s": 0.005
}
}
}

thanks

[Siddharth_H]

Hello @vderoc ,

ifx_Cube_R_t contains the real Cube and ifx_Cube_C_t contains the complex Cube (you can find this description in Cube.h file).

In app_recorder, ifx_Cube_R_t is passed to the recorder_process function. Which means that the data Cube being recorder is Real value.

Thank you, Siddharth.