AWR2944EVM: mmWave studio: clarifying received signal power for different number of Tx transmitters

Arie Rudnitsky

Intellectual 300 points

Part Number: AWR2944EVM

Tool/software:

Hi,

I want to conduct link budget measurements for a chip in lab using mmWave studio.

For BSS FW I used: mmwave_studio_03_01_04_04\rf_eval_firmware\radarss\xwr29xx_radarss_rprc.bin

For MSS FW I used: mmwave_studio_03_01_04_04\rf_eval_firmware\masterss\awr2xxx_mmwave_full_mss_rprc.bin

I see that using 1 or 2 or 4 Tx transmitters in mmWave Studio configuration doesn't change the number of observed channels (for 4 RX there are 4 of them) but changes the signal strength according to the beamforming rule: 20*log10(Ntx).

Does it mean that the system indeed executes beamforming?

Does it mean that if I want to check a link budget in lab, suitable for a DDM case, I should define a single Tx transmitter to avoid beamforming or there is a way just to configure the wwStudio to avoid beamforming?

These are my mmWave studio configuration widgets, where I change the number of Tx to 1,2 or 4 appropriately:

Arie

2 months ago

0 Shailesh Joshi 2 months ago

TI__Expert 4070 points

Hi Arie,

Arie Rudnitsky said:
I see that using 1 or 2 or 4 Tx transmitters in mmWave Studio configuration doesn't change the number of observed channels

Were you expecting to perform time division multiplexing (TDM)?

In your first screenshot, you should keep all TX enabled. That tells the device that all TXs are planned to be used in certain way.

Enabling all multiple TXs in the third screenshot, will lead to beamforming, although, TX phases may not be perfectly aligned if you are not controlling them.

For TDM, create 4 chirps and assign one TX in each, that way you will be able to see all Tx-Rx channels in your post processing plots.

Regards,

Shailesh

0 Arie Rudnitsky 2 months ago in reply to Shailesh Joshi

Intellectual 300 points

Hi Shailesh,

I wanted to consider generally DDM, NOT TDM.

But basically, currently I was focusing on measuring a link budget in lab.

For that, I need a single Tx per Rx to be used without any TDM.

Does it mean, that for this I had to enable all 4 Tx in the 1st screen, and in the 3rd screen only a single Tx?

Cheers,

Arie

+1 Shailesh Joshi 2 months ago in reply to Arie Rudnitsky

TI__Expert 4070 points

Hi Arie,

Understood. Yes, you need to enable only one TX in each chirp. You can define 4 chirps and have enabled TX0 in first, TX1 in second and so on.

You can refer to this thread on how this can be done: (+) AWR2243BOOST: How to configure MIMO Radar sensor for basic TDM with all 3 TX channels using mmWaveStudio - Sensors forum - Sensors - TI E2E support forums

Regards,
Shailesh