NFC compatibility for audio transmission

PBhan.1 · ‎2023-01-03

Hello

Can NFC tag be used to transmit audio

if yes , which type can be used from ST and what reader would be appropriate.

not the physical proximity tags but other

thanks

Peter BENSCH · ‎2023-01-04

NFC will probably not meet your requirements for several reasons. By the way, how do you define the parameters of "normal voice note" (sampling rate, sample width)?

If you want to store the audio data in an NFC tag, you need quite a lot of memory: at 4 minutes duration you need 8000*8*240=15Mbit even for very horrible sound quality (8kHz sampling rate, 8bit samples), at better quality (22kHz, 16bit) it's 22000*16*240=82.5Mbit. For 5 minutes 25% more memory each.

But the largest tags currently only have 64kbit - not Mbit.

Now about the data rate: with the better quality mentioned above we are talking about 22kHz*16bit = 352kbps, which is not feasible with NFC. Even with the horrible quality of e.g. 8kHz*8bit you get 64kbps, for which ISO15693 (NFC Type 5) with max 53kbps is no longer sufficient, even ISO14443A with 106kbps just barely.

If you now calculate backwards from 64kbit and assume the lousy sound quality, you come to

65536/(8000*8)=1.024 seconds duration of the voice message.

Would you be satisfied with a voice note of one second?

If the problem is solved, please mark this thread as answered by selecting Select as best, as also explained here. This will help other users find that answer faster.

Regards

/Peter

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Peter BENSCH · ‎2023-01-04

Welcome, @PBhan.1, to the community!

Well, NFC can transmit at data rates in the range of 26...106kbps, depending on the standard, although the rates that can be achieved in reality are lower. Audio cannot be transmitted meaningfully with this.

Maybe you can tell us more about the requirements, then we could make appropriate suggestions?

Regards

/Peter

In order to give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

PBhan.1 · ‎2023-01-04

Thank you Peter for your reply.

about my requirement :

I am looking to add NFC or similar tag to transmit just a 4 or 5 minute voice note. no additional expectation from the tag.

so when I say a voice note, that would be not some good industry standard sound quality but a normal voice note.

of course one can use other transmitters like Bluetooth etc. but I am looking for something hassle free like NFC.

your guidance would be highly appreciated to take things forward with ST.

regards

Peter BENSCH · ‎2023-01-04

NFC will probably not meet your requirements for several reasons. By the way, how do you define the parameters of "normal voice note" (sampling rate, sample width)?

If you want to store the audio data in an NFC tag, you need quite a lot of memory: at 4 minutes duration you need 8000*8*240=15Mbit even for very horrible sound quality (8kHz sampling rate, 8bit samples), at better quality (22kHz, 16bit) it's 22000*16*240=82.5Mbit. For 5 minutes 25% more memory each.

But the largest tags currently only have 64kbit - not Mbit.

Now about the data rate: with the better quality mentioned above we are talking about 22kHz*16bit = 352kbps, which is not feasible with NFC. Even with the horrible quality of e.g. 8kHz*8bit you get 64kbps, for which ISO15693 (NFC Type 5) with max 53kbps is no longer sufficient, even ISO14443A with 106kbps just barely.

If you now calculate backwards from 64kbit and assume the lousy sound quality, you come to

65536/(8000*8)=1.024 seconds duration of the voice message.

Would you be satisfied with a voice note of one second?

If the problem is solved, please mark this thread as answered by selecting Select as best, as also explained here. This will help other users find that answer faster.

Regards

/Peter

In order to give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

PBhan.1 · ‎2023-01-04

even remotely not possible.

let's change direction completely.

thanks