Realistic data rate with S112 and a mobile device

[marklander]

Hi guys,

simple question based on your experience: what is a realistic data rate between an Android device and an nrf52805 with S112 on board?

I tried a lot of tweaks using your advices here:

• connection event length extensio
• Tweaking connection intervals ( max and min )
• Tweaking MTU

Considering that on S112 data lenght extension is not available i still reach a max of 30KBytes/sec ( so 240Kbits ) which quite low respect to expected data rates.

I know that mobile are doing what they want with radio cause of OS doing other things and also I saw different androids having different performances...

Do you think this is a realistic data rate with mobiles or I am doing still something that could be improved?

Thanks!

[Einar Thorsrud]

Hi,

There are several tings that affecth throughput. Even without data length extension, you can get a better throuhgput by using an event length that is higher. You can refer to this table from the S112 SoftDevice specification for maximum throughput with different configurations. But as  you write, the central (phone) decide much of this, so even if you configure the nRF for maximum throughput, you will likely not get close to these numbers in practice.

[marklander]

Yep! Thanks for the link, i've been there in my research on data rate, and indeed I cannot get close to that numbers in my real case, wanted just to know from tech guys of your team if my number could be realistic or no...

[Einar Thorsrud]

It really depends. As you see from the table, there are things you can do. Primarily, increase the event length and ATT MTU

[marklander]

Will try again! I did some testing tweaking that parameters, but cannot get higher that about 30Kbytes/s

I will try to think back to my testing and see if I can improve...