Voice over Thread

RE: Voice over Thread

redsun — Wed, 07 Feb 2018 23:00:32 GMT

Just add poweramp (+25 dBm IC from Skyworks) and matched external antenna, 3*5/8 with should be enough, it all can give approximately 10 Watts EIRP

RE: Voice over Thread

ovrebekk — Wed, 24 May 2017 13:27:50 GMT

Hi Albert

I am happy to help :)
Feel free to accept my answer if you consider the case closed.

RE: Voice over Thread

Albert — Wed, 24 May 2017 08:37:59 GMT

Hi Torbjørn,

Thanks of all the answers.

Regards, Albert.

RE: Voice over Thread

ovrebekk — Wed, 24 May 2017 06:18:11 GMT

Hi Albert

250kbps is the on-air bitrate, not the data throughput. In a wireless system the throughput will always be lower than the on-air bitrate, which is why it is approximately 128kbps for thread. I was told the first additional hop would reduce the throughput by a factor of 2, and that additional hops would reduce the throughput a bit more (but not by a factor of 2 for each one).
Like most RF systems thread is simplex, you can only transmit one way at any one time.
The maximum number of router hops is 16. If you include a child node at each end you could get 17 hops in total.

Best regards
Torbjørn

RE: Voice over Thread

Albert — Tue, 23 May 2017 11:47:35 GMT

Thanks for the answer. May I know the following which I could not find doing web search.

is the 250kb throughput dropped by half for every hop.
is the 250kb duplex or simplex speed,?
what's the max hop support by thread?

Regards, Albert.

RE: Voice over Thread

ovrebekk — Tue, 23 May 2017 10:08:29 GMT

Hi Albert

It depends on the data rate you need, as thread is not really designed for streaming applications.

Theoretically you should be able to go up to about 128kbps between two thread nodes, but once you need to do multi hopping that drops by a factor of 2 or more.
Secondly, we have yet to do any bench marking of our own implementation, so we can not guarantee at this point that the practice will meet the theory ;)

In other words I am a bit uncertain if thread is suitable for reliable audio transfer.

Best regards
Torbjørn

RE: Voice over Thread

endnode — Sun, 21 May 2017 22:32:07 GMT

And is Voice over IP the best solution here? Assuming it's basically always point to pint and in the relative short distance (as you speak about Thread and BLE) then you can use some optimized protocol on top of BLE or some proprietary 2.4GHz link to transport sound in reasonable quality for intercom/voice application, there are people succeeding even on nRF51 few years back on this forum, with nRF52840 it should be comfortable task. Just an idea...

RE: Voice over Thread

Albert — Sun, 21 May 2017 00:16:49 GMT

I have looked at Bluetooth 5 LE and the upcoming Bluetooth Mesh and still in specification stage where as the 803.15.4 is well established standard and Thread is IP based. BLE with IP looks more like a band aid solution.

RE: Voice over Thread

Turbo J — Sat, 20 May 2017 12:50:03 GMT

With the usuable range of BTLE in mind, just shouting loud would be a much more efficient way to transport voice.