How can i increase throughput

[T_chapelle]

Hi all !

I'm trying to evaluate the throughput i can have between a Motorola 4G and the nrf51. The nRF51 is the peripheral and the phone is acting as a central.

To do that, i've based my work on the nRFToolbox android source code and modified the uart example. It read a file and send it by chunk of 20 bytes to the BLE peripheral by writing to the characteristic with the functions "mRXCharacteristic.setValue(data);" and "writeCharacteristic(mRXCharacteristic);"

On the nRF51, i've modified the peripheral uart example as well. I use the SD130v2 with SDK11. It gather the 20 bytes messages and send them to the uart using the "nus_data_handler()"

So far, i've tested different files size and succeed on getting a data rate of 1.25kbps with packet ack and 2.5 kbps without it (setWriteType(WRITE_TYPE_NO_RESPONSE) on android) and by lowering the connexion interval to 7.5ms.

After reading

devzone.nordicsemi.com/.../ devzone.nordicsemi.com/.../ devzone.nordicsemi.com/.../how-can-i-improve-throughput-for-ble-link

, i think i understand that i can achieve better data rate by increasing the packets sent per connection event.

...But i can't find a way to do so on the android side. Can you please give me hints or guidance to send multiple packets per connection even ? Also, i don't want to use a large write :-)

Thank you !

[Jorge]

I don't know if this is what you already doing (sorry if it is), You can try to use the UART app on the nRFToolbox and send a message with more than 20 bytes. From what I searched your phone should be able to send/receive 4 packets per connection interval. So if you send something with 80 bytes it should be sent on the same connection interval. Can you achieve this?

PS' a tip to you is when you edit some question or comment, if it's not a major edit you should check the box below the "save comment" which says "minor edit" that way we receive less emails ;)