Throughput on nRF51822 USB dongle

[George D]

Does anyone have any solid numbers on the maximum throughput achievable on the nRF51822 USB dongle that comes with the nRF51822 Eval Kit?

Application - OTA protocol Gazell, three remotes transmitting 108 (data) bytes at each 600us timeslot. Resultant data rate - 180KBytes/sec (+ protocol overhead).

Can the USB dongle (and driver) handle this rate?

~GeoD

[Håkon Alseth]

Hi,

Gazell for nRF51 can only handle 1 packet every 2 x timeslot. Given the lowest timeslot for 2Mbit on-air data rate, you will see a maximum throughput of: 1000/1.2 * 32 byte * 8 = 213.3 kBit/s

Getting through 180 kByte/s (1.44 Mbit) will be very hard in general, as overhead and startup time will have a great impact. You may reach speeds of around 1 Mbit/s if no ACKing is used, and no RF protocol is used (ie: example based upon radio_example in the SDK)

Regarding the UART-USB bridge on the SEGGER, we've tested 460k baud w/flow control and did not see any corruption.

Best regards Håkon