BOOSTXL-AOA: About number of Antenna element

Shoko

Intellectual 745 points

Part Number: BOOSTXL-AOA

Hello,

I have some questions about number of Antenna element of BOOSTXL-AOA.

It is indicated the formula of converting to AOA angle using phase difference between two antennas

in step3 of "Bluetooth Low Energy Angle of Arrival (AoA)".

There are three antenna elements per an array on BOOSTXL-AOA.

Question;

1) Why BOOSTXL-AOA has three antenna elements per an Array?

I think even if there are only two antenna elements per an array, it can achieve.

How effect can be expected from that?

2) If there are ten antenna elements per an array on BOOSTXL-AOA,

can it mprove significantly the accuracy of angle estimation?

Please advise.

Shoko

over 6 years ago

0 Sai Reddy over 6 years ago

TI__Mastermind 22580 points

Hello Shoko,

I will forward this to the concerned team.

Thanks,

Sai

0 J Lindh over 6 years ago

TI__Guru 57865 points

Hi Shoko,

You are correct that only two antennas could be enough. The board is an evaluation platform that provides many potential usages.

0 Shoko over 6 years ago in reply to J Lindh

Intellectual 745 points

Dear Joakim,

Thank you for your response.

I have additional questions about number of Antenna element of BOOSTXL-AOA.

- Three antenna elements of array are all active when AOA RTLS monitor is working.

(Please see the attached image. )

How does it calculate angle using two pairs of antenna (I think use A1.1&A1.2, A1.2&A1.3) in AOA RTLS monitor?

Please advise.

Thanks, Shoko

0 J Lindh over 6 years ago in reply to Shoko

TI__Guru 57865 points

Hi,

See this SLA:

http://dev.ti.com/tirex/explore/content/simplelink_academy_cc13x2_26x2sdk_3_20_03_00/modules/rtls_toolbox_ble5/ble_aoa/ble_aoa.html#introduction

0 Shoko over 6 years ago in reply to J Lindh

Intellectual 745 points

Hi Joakin,

Thanks for your reply.

I have already read the linked page.

However, it is not described the explanation of relation between A1.1&A1.2 anf A1.2&A1.3.

Could it be that AOA RTLS monitor JUST displays the angle data of A1.1&A1.2 and the angle data of A1.2&A1.3??

I completely thought that it averages using by the angle data of A1.1&A1.2 and A1.2&A1.3!

Thanks, Shoko

0 Clément over 6 years ago in reply to Shoko

TI__Guru** 101450 points

Hi Shoko,

Regarding the relation between A1.1&A1.2 and A1.2&A1.3, the answer to this question is in Joakim's link (exactly here: http://dev.ti.com/tirex/explore/content/simplelink_academy_cc13x2_26x2sdk_3_20_03_00/modules/rtls_toolbox_ble5/ble_aoa/ble_aoa.html#task-2-ndash-modify-aoa-application-to-use-only-one-antenna-array)

"The angle is then decided once both arrays have received AoA packets and judge by the rssi value of the received packet to decide whether the application should trust angle derived from array 1 or array 2.

[...]

However, this might not be how you want to design or utilize your antennas."

Regards,

0 Shoko over 6 years ago in reply to Clément

Intellectual 745 points

Hi Clement,

That is not what I wanted to know.

I want to know the relation batween "ANTENNA ELEMENT PAIRS" A1.1&A1.2 and A1.2&A1.3, not the relation of antenna arrays.

It's described only the explanation of the relation between antenna array A1&A2 in the linked page, not antenna element pairs.

------
Could it be that AOA RTLS monitor just displays the angle data of A1.1&A1.2 of array A1 and the angle data of A1.2&A1.3 of array A1?

Please reply.

Regards, Shoko

0 R.M over 6 years ago in reply to Shoko

TI__Genius 9215 points

Hi Shoko,

It's not quite clear what you are asking for but for AoA it measures the phase difference between A1.1&A1.2 and the phase difference between A1.2&A1.3 on antenna array 1 and then take the average. The same is done for antenna array 2 (average of phase difference between A2.1&A2.2 and A2.2&A2.3). Then the algorithm picks the antenna array that have the strongest RSSI and report back the result from that antenna array. This is then what's reported back to AOA RTLS monitor.

Does this answer your question?

Best Regards,

R.M

0 Shoko over 6 years ago in reply to R.M

Intellectual 745 points

Hello R.M

Thank you very much for the response. That's exactly what I wanted to know.

Thank you,

Shoko

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BOOSTXL-AOA: About number of Antenna element