Advertiser and new connection makes data transmission speed slower.

RE: Advertiser and new connection makes data transmission speed slower.

TGuanLa — Thu, 27 Oct 2022 09:04:43 GMT

Thank you so much!

RE: Advertiser and new connection makes data transmission speed slower.

Einar Thorsrud — Thu, 27 Oct 2022 08:56:08 GMT

Yes, there is. To maximize the throughout between the central (A) and the peripheral (B), you should ensure that B spends less time on other things like advertising and/or maintaining a connection with the phone (C) as well. So:

Increase the advertising interval (this is only relevant when advertising, not sure if you do that when you have established the second connection).
Use a longer connection interval on the second connection (between the peripheral B and phone C).
Use a shorter event length on the second connection (between the peripheral B and phone C).
Use slave latency on the second connection (between the peripheral B and phone C).

Note that it is the central that decides the connection parameters, but you can configure the nRF with the preferred parameters, and most recent SDK examples will then request a connection parameter update with those parameters.

RE: Advertiser and new connection makes data transmission speed slower.

TGuanLa — Thu, 27 Oct 2022 07:10:09 GMT

Thank you for your answer.

Is there any way to improve the data transmission speed of A and B when B has two connections?

RE: Advertiser and new connection makes data transmission speed slower.

Einar Thorsrud — Wed, 26 Oct 2022 14:13:59 GMT

Hi,

There is only a single radio, and it cannot receive and transmit at the same time. So when the peripheral advertises, that means that there less time for the connection (how much less depends on the advertising interval). Similarly, when your phone connects to the peripheral (B), it now has two connections, and there is even less time for the connection with A. Moreover, these are not synchronized as a peripheral has no influence over this, so here might be quite a lot of overlaps/collision of the connection events with the two connections.