How to acheive high data rate?

[balaji]

Hi,

Is there any difference(data rate) between sending large data packets through single characteristics and multiple characteristics?

I have created one characteristic with notify property and also created a buffer of size 20 bytes(packet size). I did transmitting the buffer until the sent data size reaches 200KB (transmitting in a for loop until the count reaches 10240).

The problem i face here is, time consumption. For me it took ~36 seconds to transmit 200KB of data. Hence i can only achieve the data rate of 5KB per second. I know that the data rate can be achieved using BLE is 2Mbps,1Mbps and 250kbps.

So please suggest me how to achieve the data rates as specified in the BLE document. Actually i need to transmit the 200KB of data within 1 or 2 sec.

I also tried sending the data using 2 different characteristics. Now each will send 20 bytes of data for 5120 times, but the data rate i achieved is same as above.

I also made changes in the minimum connection interval and maximum connection interval to check whether the required data rate is achieved or not , but i did not get any result as i expected. I also attached my testing results. Please suggest me the min and max connection interval need to be set.

Regards, Balaji

[syntroniks]

The data rate may be high, however throughput is not. With a small maximum payload size in the bluetooth low energy protocol, you will not achieve 1Mbps even if the underlying radio can.

200kb is a large application size and I have seen bluetooth low energy over-the-air updates take nearly half a minute like you describe.

You are already using the shortest connection interval that still meets the BLE SIG spec, perhaps higher datarates are possible with nordic's gazelle or enhanced shockburst.