Multiple point-to-point links

[abc]

I am trying to decide what Nordic solutions would best support the application throughput requirements seen below. Distance requirements are low (1 meter each link).

I was planning to use proprietary 2.4 GHz for links (1,3) and (2,3), and BLE for link (3,4). Specifically, nRF24 on nodes 1/2 and nRF51 on node 3. (Node 4 already has BT/BLE support.)

Does it make sense to use the protocols as described, or should I consider something else, e.g. Classic BT for links (1,3) and (2,3)?

Would an nRF51 at node 3 be able to support the multiprotocol Rx/Tx throughput? I have seen for instance this page on both concurrent and non-concurrent 'multiprotocol support'.

[Hung Bui]

I don't see any problem with the design.

Yes, you can use ESB protocol between 1, 3, 2 and use BLE between 3 and 4.

You can use nRF24 on 1 and 2, but nRF5x is recommended as they are newer chip and can provide extra future prove if you gonna upgrade the protocol later on (OTA DFU supported)

We have example for multiprotocol concurrent support. You can have a look here and here.

[abc]

Thanks for the links. I'll take this as a confirmation that the throughput can be handled. You mention using ESB, which I understand is a pared down version of Gazell. Would Gazell be overkill in this case? I like that it has better interference handling, as well as bi-directional and encryption support.

[abc]

Concerning nRF24 vs nRF5x, I am mainly looking at cost. I plan to have a 5-10k initial run of the above system, and if nRF24 (non-SoC) is cheaper than nRF5x by $0.50, I think it makes sense to go with the nRF24. Additionally, the uC features of the nRF5x are overkill for nodes 1 and 2. If this is the wrong venue to ask such questions, maybe I should talk to an application/technical sales engineer?

[Hung Bui]

ESB is also bi-directional. Through put on ESB can get to 700kbps with 1Mbps mode and 1.2kbps with 2Mbps mode. I'm not so sure about Gazel, but it should be able to handle 200kbps. And you are right that ESB doesn't have encryption supported, implementation on application level needed. If you don't plan to have multiple client, no more than two, Gazel perfectly fits.

I'm not so good at the pricing, so yes, you should talk to our sale representative/distributor. You can find the list of distributor for your area in the Distributors section in the footer of our website.