Connection Problem

[sara]

Hello,

Environment: nRF51DK + SDK8

We've developed the beacon application but the advertising interval is set to 5 seconds. The beacon can be discovered by nRF Connect App (ios) but iPhone is really hard to connect with it.

The question is that is this problem related to the longer advertising interval? Is there any method to improve performance? Or there is only one solution that must shorten the advertising interval?

Thanks.

[Adrian Eggenberger]

Hi,

A device with an advertising interval of 5 seconds may be difficult to connect. The advertising is a broadcast and multiple advertisings of various devices may interfere. Additionally the central devices often don't scan permanently (it's an option in the bluetooth API and choosen by the central application). In fact it's normal that not all advertisements are received by a central device.

The central devices may start connecting to a peripheral. In this case the central will wait for the next received advertisement and respond to it with the connect request. A successful connect will result if within the connect timeout period a advertising is received and the connect sequence can be finished properly. The duration of the connect timeout may be set by the central, but a timeout of 5 seconds or less is not unusual.

I see the following options for your problem:

• Lower the advertising interval permanently or in certain situations (will result in higher current consumption)
• Increase the timeout for the connect (only possible if you write your own app and will result in long connect periods)

Regards Adrian