how can I improve throughput for ble link?

[Ben.Qin]

I found many relative topics about improving throughput for ble link on this website. And this one How do I calculate throughput for a BLE link? told me how can I calculate the throughput. I thought "n" is beyond my control. It should be decided by protocol stack, right? This discussion dealing large data packet's through ble gave me an example and told me many details. I did in another similar way. I didn't use heart rate service but Nordic UART service, and I confirmed configurations, such as vlen = 1, max_len = 20, hvx_paprams.type = BLE_GATT_HVX_NOTIFICATION and so on, are the same as I was told. My peripheral is base on nrf51822 and s110_nrf51822_6.0.0_softdevice, while the central is Nexus 7 with android 4.4.4. I got just about 16Kbps throughput. But it's said that it should be more. Whatever connection parameters I set, it didn't seem helpful. What did I do in a wrong way?

[Stefan Birnir Sverrisson]

Hi

Perhaps this blog post will give you some hints on the subject.

Update 13.10.2014 Try the throughput test example which is linked to in the blog post. The Nexus 7 might not be able to receive more than 1 packet per connection interval, and that might be the problem, but the best way to find out is to sniff the on air traffic to see what is actually going on.

For best throughput, make sure you have selected 7.5ms connection interval in the nRF51 application.

[Ben.Qin]

@Stefan Birnir Sverrisson, I read the blog post, a very good article. I checked the configuration in my project, snippet memset(&hvx_params, 0, sizeof(hvx_params)); hvx_params.handle = p_nus->rx_handles.value_handle; hvx_params.p_data = p_data; hvx_params.p_len = &len; hvx_params.type = BLE_GATT_HVX_NOTIFICATION; making clear the server(nrf51822) should work in notification mode, not indications mode, right? If so, I don't suppose I should have done something wrong to configure the packets type.