ANT Forum

We're considering using the S310 softdevice on an nRF51422, operating it as follows:

1) ANT Continuous Scan Channel opened for 1 second every 5 seconds
2) Full-time BT-LE connection with a 12.5-22.5 ms connection interval.

What are the issues with concurrent operation such as this? Will we have to use background scanning, rather than continuous scanning on the ANT channel?

Thanks,

Scott      

Hello Scott,

In concurrent operation for the scenario you describe, the ANT continuous scanning mode can run in coexistence with BLE activities, however, its performance will degrade based on the frequency of the BLE activity. This is because the ANT continuous scan will run at "best effort" in presence of BLE activity, attempting to run in between BLE advertising/connection events.

Based on the frequency of the BLE connection events you describe (12.5 - 22ms) , the impact in the ANT scanning performance will be very noticeable. From internal testing, it looks like the scanning mode will only be active for approx. ~ 7 ms in between BLE connection events, limiting its capture capability. Additionally, any ANT packets that are synchronous or closely aligned to the BLE packets in time may be missed. You will need to do some testing on your end to determine if the 1 second ANT scanning interval is sufficient to capture the ANT transmissions you are wishing to see.

A background scanning channel will not result in any improvements on the ANT side, as its ability to capture ANT transmissions will degrade similarly with such high frequency of BLE activity.

This information is based on SoftDevice s310 V1 production release.