NUS (Nordic UART Service) maximum rate

[Mahmoud]

Hi - I am using NUS (Nordic UART Service) to send raw sensors data over BLE to my PC for later processing. However, I found that I can not get a more-than-20-packets-per-second rate; no matter what is the size of the packet (1 byte + 5 header to 22 bytes + 5 header). I wonder if this is the maximum rate that I can get over the NUS, or there is a way to increase it.

Thanks,

[max]

Try also set connection interval to minimum and use a notification option from the BLE device to your PC.

[endnode]

Definitely not the maximum, all throughput demos by Nordic are basically using NUS, see the blog posts (128kbps on link layer without BT 4.2/5.0 extensions):

• devzone.nordicsemi.com/.../
• devzone.nordicsemi.com/.../

Simply choose some example FW from Nordic GitHub which they use for these throughput demos and learn from there. Indeed these demos are taking advantage of mastering both ends of the link. If one of these is some blackbox stack like PC or phone/tablet then indeed you cannot achieve all that. However still 1-10kBps should be possible on APP layer over GATT.

[Mahmoud]

The problem was in the BLE driver of the LabVIEW, this is the MAX rate it achieves with different sizes of the packets. I tried it with noble_node.js and I could get around 130 packets per second (130*27 = 3510 Byte per second -> around 3KBps) which is good for what it is for.

[Mahmoud]

Thanks! I will try that when I have a chance.

[Mahmoud]

I could get a similar rate with Windows 10 API; i.e. around 3KBps.