IWR6843: Changing frequency of radar

Hi,

Any suggestions on this?

Thanks,
Manoj

Hi Manoj,

You can use IWR6843 in the 61-64GHz band.

Selection of frequency is done in profileCfg CLI in the configuration file

For example 

Hi Abhishek,

Thank you for your response. There is a little change in frequency range, my bad. Licensed frequency range is 61-61.5GHz, not till 64GHz.

1. If I change frequency of the chirp 61GHz in the configuration file, will it be within range of 61-61.5GHz?

2. Do I need to change only this parameter from 60 to 61 in profileCfg or any other supporting parameter that I need to change? And if I change frequency from 60GHz to 61GHz will affect functionality of radar?

3. How to monitor slope and the ramp end time to confirm that it does not go beyond the 61.5GHz? Is there any tool to monitor these parameters? 

Regards,
Manoj

Hi Manoj,

1. When you change the frequency as I mentioned above, it will change the start frequency. In your case you can set it to 61GHz. Now, to make sure you do not go beyond 61.5GHz, you need to program the slope and the ramp end time correctly. Slope is the change in frequency in microsecond. Ramp end time will determine the chirp duration. To be within the range of 61-61.5GHz, you can program slope of 25 MHz/us and Ramp end time of 20us

2.You need to change the Start frequency, Slope, Ramp end time and Sampling rate and No of Adc samples to be within the range of 61-61.5GHz

3.I explained it in point 1. You can refer to TI sensing estimator for more details. Below is the link

https://dev.ti.com/gallery/view/mmwave/mmWaveSensingEstimator/ver/2.4.0/

Regards

Hi Abhishek,

I have configured the parameters. Please find the image below,

Please let me know if it is correct. And what will be the difference in functionality or performance of the radar as compared to old configuration (currently using) if I use these new parameters?

Old configuration parameters are, 

profileCfg 0 60 35 6 43.0 0 0 8.241 1 125 3433 0 0 48
channelCfg 15 7 0
adcbufCfg -1 0 1 1 1
chirpCfg 0 0 0 0 0 0 0 1
chirpCfg 1 1 0 0 0 0 0 4
frameCfg 0 1 128 0 100 1 0

In above image, Number of Tx Antennas if I set to 3 then it asks to enter chirpCfg3 which is not there in old config file. And if I change it to 2 then it allows me to calculate parameters. But as per old configuration "channelCfg 15 7 0" (2 azimuth and 1 elevation antenna) but in the above image it is "channelCfg 15 3 0". Any inputs on this config parameters?

Regards,
Manoj

Is there any specific reason you want to use only 2 transmitters?

Using more number of virtual antennas provide better angular resolution. So, you need to use 3TX/4Rx as the device supports. This is indicated by channelCfg. chirpCfg3  is included if 3rd Tx is selected. For optimum performance you need to use all 3Tx/4Rx which will result in channelCfg 15 7 0

Regards

Hi Abhishek,

There is no specific reason using it. I am using "6843_50m_2D" config file. So, as per your suggestion for optimum performance I shall use "6843_50m_3D" config file where 3Tx/4Rx is configured?

And please let me know if above configuration is correct, shared with screenshot.

Thanks,
Manoj

Where are you picking "6843_50m_3D" from? 

I am picking that config file from "ti\mmwave_industrial_toolbox_4_12_1\labs\Long_Range_People_Detection\chirp_configs" folder. 

Hi Abhishek,

Any suggestions on this?

Regards,
Manoj

Hi Manoj,

The configuration is fine. You can modify based on your requirements. What specific application you are looking at?

As your frequency range is very specific, applications supported in radar tool box may not work. You can try to make out of box demo work with your configuration first

Please download the latest radar tool box. Industrial and automotive tool box is combined to create radar tool box

Regards

Hi Abhishek,

My application is obstacle avoidance application. I will mount radar on UAS (Unmanned Aircraft System) to avoid obstacles coming on its way. I am using LRPD application since it gives me long range up to 50m range also it detects power cable. We have done all the testing till now on LRPD which fits to our requirement. 

Regarding frequency range is very specific because we want to use it for commercial as well as for defense purpose. In India allowed frequency range is 61 to 61.5GHz for license. So, to fit into it we are very specific to this frequency range.

Regards,
Manoj