nRF52840 maximum data throughput

[DJ]

How many nRF52840 chips can be used simultaneously? Can all data and advertisement channels be used at maximum capacity (2Mbps/each) to result in an overall throughput of 2Mbps*N where N is the number of nRF52840 chips < # of channels available?

Thanks

[endnode]

Hi DJ,

What do you mean by simultaneously? This is so vague that I even cannot give you one from all the myriads of answers. On the second question: in theory you might get continuous 2Mbps with some proprietary radio protocol but I'm not sure that chip would handle it for long time. In addition it's practically useless unless you are in some kind of lab environment such (e.g. shielded chamber). Your questions indicate that your application is most probably not suitable for this range of embedded low energy ICs, are you sure you don't want to use some other off the shelf technology like WiFi?

Cheers Jan

[DJ]

Hi Jan,

Thank you for your reply. The application of interest indeed requires >2 Mbps and I'm exploring options to do so in the lowest power possible. I fully agree with you regarding caveats in getting 2 Mbps from each of this module (e.g., overhead, reliability, signal integrity, etc.). However, assuming we can do that for the sake of argument, my question was how many of these nRF52840 chips can be used, independently (or simultaneously), to increase the overall throughput?

For instance, perhaps you can de-tune the center frequency or leverage the fact that there are separate data / advertisement channels to get higher total bandwidth (independent data stream). As an example, if I were to use, say 10 of these nRF52840 (configured as TX), each streaming at 2 Mbps to a receiver that can handle this load (less power constraint here), could I get an effective bandwidth of 20 Mbps? **

Hope this clarifies my original question.

Thanks, DJ

** It's possible the overall power consumption of 10 of these chips, fully streaming, might consume more overall power than other solutions.

[Roger Clark]

I recommend you use WiFi as IMHO BLE is not designed for the sort of application you have outlined

(Yes. WiFi may take more power, but you don't get bandwidth without taking more power)

[endnode]

Hi again, first you need to be very specific about what networking protocol you are talking about. 2Mbps is some physical bitrate modulated on top of one channel inside 2.4GHz ISM band. That has very little to do with throughput which is your concern. So are you taking about theoretical (proprietary) data transfer over nRF52840 radio or some specific protocol stack like BLE or IEEE 802.15.4 or ANT or what? Then you are talking about running it simultaneously. Do you mean having several chips on both sides and parallelize the stream? As most of the protocols are peer to peer you can of course run like that until you have available bandwidth in the radio. And this is again determined by the protocol stack you want to use because they differ in terms of number of channels, channel allocation (or hopping), link reliability mechanisms, overhead in lower layers etc.

[endnode]

Btw. for BLE here is maximum throughput demo with BT5.0 2Mbps feature and all possible PDU, ATT_MTU and Connection interval extensions. This gives you 1.3~1.4Mbps. Note that this is most probably on the link layer and that this is one way unacknowledged (and most probably unprocessed) streaming. If you want to do any meaningful with the data it will drop, but how much is very application specific.