Are the Radio RX power consumption values of connectable advertising in the Online Power Profiler relatable to power consumption of the Radio RX component of BLE scanning?

[Mathias]

Hi,

Just a small question, as the subject indicates: Is the power consumption for the Radio RX component (per µs) indicated in the Online Power Profiler for connectable advertising (https://devzone.nordicsemi.com/nordic/power), relatable to the Radio RX component of BLE scanning indicated in the datasheet for the SoftDevice (and thus also relatable to BLE scanning for Bluetooth Mesh)?

Kind regards,

Mathias

[haakonsh]

Yes, you're correct. Though note that scanning for BT mesh is constant. 

[Mathias]

Ok, thanks for your answer. So because of scanning for BT mesh being constant, probably the initial start of scanning (upon power-up of the mesh node) is relatable to the Figure below? Meaning that scanning will start on channel 37 from (A) to (E):

But what happens when:

- Switching to another channel: Will (F) and (G) occur and/or will (A), (B) and (C) occur again? Or is it just (D) and (E) sequentially?

- Receiving a packet and resuming scanning: In the SoftDevice specification it says that (F) and (G) occur upon receiving a packet. Is this the same for BT mesh? And afterwards, when resuming scanning, will again (A), (B), and (C) occur before (D) and (E)? Or is only (D) and (E)? And is scanning resumed on the channel is was scanning on and using the time that had already passed of the scan interval?

- Transmitting a packet and resuming scanning: For transmission timings, I've asked a separate question here (https://devzone.nordicsemi.com/f/nordic-q-a/53483/relation-between-broadcast-c-timings-the-online-power-profiler-timings-for-non-connectable-ble-advertising), so I won't ask anything about that here. But again, afterwards, is the resuming of scanning done on the channel it was scanning on before and using the time that had already passed of the scan interval?

Thanks!

Mathias

[haakonsh]

Switching channel:
I don't think there's much difference as the radio only has a minor state change, there will be a few µs CPU time needed to change the radio. This will propably manifest itself as a short dip in current consumption compared to the constant scanning.

Receiving a packet and resuming scanning:
"In the SoftDevice specification it says that (F) and (G) occur upon receiving a packet. Is this the same for BT mesh? " Yes, exactly the same. 
"will again (A), (B), and (C) occur before (D) and (E)? Or is only (D) and (E)? ". I think the the HFXO will remain operational after the receiver has received a packet if there's still time remaining ing the scan window. I've asked my colleagues for a more definite answer.

"is the resuming of scanning done on the channel it was scanning on before and using the time that had already passed of the scan interval?" If it resumes the current scan window then it will also use the current channel. The channel is not changed until the scan window is complete.

[Mathias]

Ok, thanks! I'll await the definitive answer on the second point of your colleagues.

Also, do I understand correctly, that when receiving a packet but during receiving, the scan window times out, the receiving of the packet is first completed and after that, the next scan window (on the next channel) is started?

[haakonsh]

haakonsh said:

I think the the HFXO will remain operational after the receiver has received a packet if there's still time remaining ing the scan window. I've asked my colleagues for a more definite answer.

 My colleagues think the same.