AWR1843: Why the max range non beamsteering and beamsterring is the same while angle less than 40 degrees?

kuowei lin

Part Number: AWR1843

Why the max range non beamsteering and beamsterring is the same while angle less than 40 degrees?

We checked from the design guide "Beamsteering for Corner Radar Reference Design", and the test result for max range non beamsteering and beamsterring is the same while angle less than 40 degrees.

https://www.ti.com/lit/ug/tiduev0/tiduev0.pdf?ts=1689312359294&ref_url=https%253A%252F%252Fwww.google.com%252F

If non beamsteering mode is MIMO mode with TDM, it does not make sense to have the same detection ability as beamsteering mode.

Since I cannot find this demo with the Automotive Toolbox from the TI Resource Explorer, I would like to know the profile settings for Non Beamsteering.

https://dev.ti.com/tirex/explore/node?a=VLyFKFf__3.2.0&a=VLyFKFf__4.0.0&node=A__AHImI8gIT9rka73eMxmrrw__com.ti.mmwave_automotive_toolbox__AocYeEd__LATEST

I guess it is not MIMO mode by TDM (AWR1843 EVK), it should transmit TX1 & TX2 & TX3 at the same time to get the longer detection range.

But the HFOV should be narrow by transmit TX1 & TX2 & TX3 at the same time, thus, +-40 degrees keeps the same range detection as beamsteering mode, it does not make sense as well.

In order to clarify it, could you help me to get more information?

Thanks a lot.

over 2 years ago

0 E. Shareef over 2 years ago

TI__Genius 15820 points

Hello,

Thank you for reaching out to Texas Instrument. Upto +-40 degrees, the Antenna has a good gain hence there is no difference between the beam steering and non beam steering range. I will provide you the information requested by early next week.

Thanks,

E. Shareef

0 E. Shareef over 2 years ago in reply to E. Shareef

TI__Genius 15820 points

Please see below exapriment for additional support on this topic:

dev.ti.com/.../node

0 kuowei lin over 2 years ago in reply to E. Shareef

Prodigy 210 points

Hi Ehtesham,

Checked from TI resource, I guess it is

"The first configuration (MRR) uses a TX beamforming with all the 3 TX transmitting simultaneously."

for non beam steering.

Am I right? If it is, we simulate the HFOV, it is around 34 degrees@-6dB.

Therefore, for the "Upto +-40 degrees, the Antenna has a good gain", is this okay?

Thanks.

0 E. Shareef over 2 years ago in reply to kuowei lin

TI__Genius 15820 points

In the example that I have sent, the beam steering is configured as follows:

Max Angle = 60 deg
Min Angle = -60 deg
Angle Step Size = 20 deg
The beams are alternating as follows:
- -60deg; -40deg; -20deg; 0deg; 20deg; 40deg; 60deg;

Broadly speaking the two modes of operation are:

MRR: Utilizing simultaneous transmission using BPM.
USRR: Utilizing alternate transmission using TDMA.

Hope this helps,

-E. Shareef

0 kuowei lin over 2 years ago in reply to E. Shareef

Prodigy 210 points

Thanks for the information.

I do understand the beam steering configuration for MRR & USRR, how about the non-beam steering mode?

Is it 3 TX transmitting simultaneously with phase 0?

Besides, AWR1843 support BPM (Binary phase modulation) mode?

https://www.ti.com/lit/an/swra554a/swra554a.pdf

Many thanks.

0 E. Shareef over 2 years ago in reply to kuowei lin

TI__Genius 15820 points

AWR1843B does support BPM. All TI devices should support BPM. During BPM, the TX phases are either 0º or 180º.

-E. Shareef

0 kuowei lin over 2 years ago in reply to E. Shareef

Prodigy 210 points

Thanks, Ehtesham.

Understood BPM supported on AWR1843.

Let's back to the question itself.

Why the max range non beamsteering and beamsterring is the same while angle less than 40 degrees?

Non-beamsteering: BMP mode (3 TX transmit simultaneously with phase 0/180)

Beamsteering: (3 TX transmit simultaneously with phase shifter)

It assume that the HFOV for Non--beamsteering is around 24 degrees @-6dB, thus I am wondering why "the max range non beamsteering and beamsterring is the same while angle less than 40 degrees?"

0 E. Shareef over 2 years ago in reply to kuowei lin

TI__Genius 15820 points

Hello,

Could you elaborate on how you came to the conclusion that the HFOV for Non--beamsteering is around 24 degrees?

-E. Shareef

0 E. Shareef over 2 years ago in reply to E. Shareef

TI__Genius 15820 points

HI,

I am going to close this thread, you can still post updates and we can reopen if required.

0 kuowei lin over 2 years ago in reply to E. Shareef

Prodigy 210 points

Sorry for late reply.

Ehtesham,

We check HFOV by -6dBm of the main beam peak power, it is around 24 degrees.

(By simulation tool, like HFSS..etc)

0 E. Shareef over 2 years ago in reply to kuowei lin

TI__Genius 15820 points

There are many factors that could influence your simulations in HFSS. During test on AWR1843BOOST, TI can confirm the 3dB-beamwidth is approximately ±28 degrees.

Coming back to your question, I am guessing the main lobe is loosing peak gain due to steering between +-28 to +-40 degrees. I am in the process of confirming the max range for beamsteering case between +-28 to +-40 degrees.

-E. Shareef

0 kuowei lin over 2 years ago in reply to E. Shareef

Prodigy 210 points

Thanks, Ehtesham.

Wait for your update.

+1 E. Shareef over 2 years ago in reply to kuowei lin

TI__Genius 15820 points

Kuowei,

The numbers listed in this table are correct. You will see these numbers on the 1843BOOST EVM. We did expect the beamsteering to show better range at 40 degrees, but unfortunately that was not the case.

TI concluded that the 1843BOOST antenna would not be optimal for beamsteering as the main lobe is loosing peak gain.

Thanks,

E. Shareef

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AWR1843: Why the max range non beamsteering and beamsterring is the same while angle less than 40 degrees?