ESB with Timeslot Throughput Issue

[Ha]

Hello Nordic People,

I am working on making concurrent operation of ESB and BLE to set up sensor network. Currently, the initial set up has been implemented in such that: first device one samples data (internal ADC) and sends the data to second device through ESB (using timeslot API, and no ack) and the second device samples its own data (internal ADC) and transmits all data together with one from ESB.

The problem currently is that it looks like a large portion of data, sent from ESB, is lost during BLE sending as it looks like BLE event takes a bit too long. While timeslot API doesn't break the BLE connection, it still not a perfectly concurrent operation between ESB and BLE (if I understand correctly) as they basically use single radio. Also, I observed that the data from 1st device and 2nd device has a delay about 3ms.

My question now is, is there any effective way to achieve high throughput and minimum delay between two protocol using Timeslot API? Or do I have to use additional BLE radio so that two device communicates in ESB and send the data to BLE radio to achieve high throughput?

[Øyvind Karlsen]

Hi,

When you do not use ACK you will have packet loss. With your timeslots you need to make sure that you are actually receiving on the multiprotocol device at the time you are sending from the ESB device.

You are correct that the timeslot API allows you to utilize the same radio resource, it is a type of time division multiple access.

In order to get the throughput and delay that you want you need to be able to synchronize the timeslot window with the transmission from the ESB. You could start to look into requesting windows at the interval you know that you will be transmitting ESB packets with.

Best regards,

Øyvind