MCPD mode Nordic Distance Measurement MCPD mode on nRF52840

RE: MCPD mode Nordic Distance Measurement MCPD mode on nRF52840

loquat — Mon, 13 Mar 2023 12:08:48 GMT

OK. Thanks!!

RE: MCPD mode Nordic Distance Measurement MCPD mode on nRF52840

Elfving — Mon, 13 Mar 2023 09:57:23 GMT

I guess option 1 would be the most accurate, though I can't disclose internals of our HW/SW unfortunately.

Though you can still use this public library with nRF 5 SDK.

Regards,

Elfving

RE: MCPD mode Nordic Distance Measurement MCPD mode on nRF52840

loquat — Sat, 11 Mar 2023 02:52:51 GMT

You write,

"no unfortunately it won't be possible to recreate the the Nordic Distance Toolbox using only the public information."

The conclusion is
"Impossible to do a similar implementation using only public information"

Am I correct in understanding this way?

I would like to know as a reference.
1. There is a hidden register set that does IQ sampling and you are using it
2. Using a device such as a publicly available RADIO/TIMER to "somehow" achieve the equivalent of IQ sampling.
3. None of the above
which one?

RE: MCPD mode Nordic Distance Measurement MCPD mode on nRF52840

Elfving — Fri, 10 Mar 2023 14:45:30 GMT

Hello again,

I had a talk with R&D about this, and that is something I am afraid you'll be on your own with implementing. We only support the NDT for NCS.

Regards,

Elfving

RE: MCPD mode Nordic Distance Measurement MCPD mode on nRF52840

loquat — Thu, 09 Mar 2023 15:15:14 GMT

I want to implement it on the nRF5 SDK.
I am currently using the nRF5 SDK's timeslot API and have some knowledge of the nRF52840's RADIO.

RE: MCPD mode Nordic Distance Measurement MCPD mode on nRF52840

Elfving — Thu, 09 Mar 2023 08:53:36 GMT

I just had a talk with the relevant R&D team about this, and no unfortunately it won't be possible to recreate the the Nordic Distance Toolbox using only the public information. Though you might be able to create something that is functional, though I am not sure about that.

Any particular reason why you want to do this on your own as opposed to using the NDT? You don't have to pay us anything for using it.

Regards,

Elfving

RE: MCPD mode Nordic Distance Measurement MCPD mode on nRF52840

loquat — Wed, 08 Mar 2023 13:57:36 GMT

After you answer for my question,
I wanted to do a similar implementation for the nRF52840 myself, too.
I would also like to ask a question out of personal interest.

"possible to get the phase of something"
Are you accessing a undocumented register-set to do this?
Or is it implemented with only the public register-set?

RE: MCPD mode Nordic Distance Measurement MCPD mode on nRF52840

Elfving — Wed, 08 Mar 2023 08:41:17 GMT

It might be that I am not understanding you correctly here. Though you are right in that the Nordic Distance Toolbox(NDT) isn't conforming to the way CTEs are presented in the Bluetooth specification. NDT is completely proprietary. How it isn't conforming to specification of Bluetooth CTEs is public information.

However, as it is proprietary, it is also closed source. So detailed documentation on how it works, as well as the source code itself, is not public information. Though the webinar I linked to earlier does go into some theoretical detail on how it works.

Regards,

Elfving

RE: MCPD mode Nordic Distance Measurement MCPD mode on nRF52840

loquat — Tue, 07 Mar 2023 12:52:11 GMT

Oh...

Does it mean it has a non-CTE compatible and undocumented IQ sampling feature?

If so, is that can information public?

RE: MCPD mode Nordic Distance Measurement MCPD mode on nRF52840

Elfving — Tue, 07 Mar 2023 08:38:49 GMT

No need to apologize. I should've mentioned this part in my last response.

[quote user="loquat"]

The nRF52840 should not have the IQ sampling function used in AoA etc.

[/quote]

The nRF52840 is missing the HW features needed to make a Bluetooth compliant DF solution, as there is no way to transmit or receive the CTE on this device. Though there are non-Bluetooth compliant solutions out there that uses standard Bluetooth packets where they insert data in the packet that allows the receiver to use this instead of the CTE. This can be done with the nRF52840 but we will not provide the code for the transmitter/receiver for this option, it will be up to the customer to do all this.

So, it is still possible to get the phase of something using the nRF52840. Its just without a normal CTE. In the same way, we can use the nRF52840 for the distance toolbox, since the toolbox doesn't require the same format of a CTE as direction finding.

Regards,

Elfving

RE: MCPD mode Nordic Distance Measurement MCPD mode on nRF52840

loquat — Tue, 07 Mar 2023 02:42:56 GMT

very sorry.
I didn't understand.

The nRF52840 should not have the IQ sampling function used in AoA etc.

So how do you get an IQ Phase?

I want to know that.

RE: MCPD mode Nordic Distance Measurement MCPD mode on nRF52840

Elfving — Mon, 06 Mar 2023 12:00:56 GMT

Hello,

Yeah that is available on the nRF52840 as well. For info on how it works, as well as how it gets the phase, see here.

Regards,

Elfving