Generate ultrasound with data

[winster]

First of all congrats and thanks a lot of this open source initiative. I am working on another open source Android library for ultrasound data transfer. Currently I have only audible sound based (ASK) version. Then I came across echopen.org and its android app. I believe you have ultrasound scanning with noise cancellation enabled in your Android app. Can I also generate ultrasound waves using Android so that we can embed data into it? May be this is something you would have tried to test your Android app.

[benchoufi]

hi Winster, thanks your for your interest to the project. We don't provide ultrasound waves generation but I can indicate to you codes that convert image into its ultrasound-like image. Btw, could you precise what your library of ultrasound data transfer consists in ?

best regards,
M

[winster]

Hello M,

My intention is to make it generic. Consider 2 devices kept close to each other, both have an app with this library. One device transmits ultrasound and the other receives it. The input and output to library is plain text.

There are libraries like chirp and nearbytes which offer the same. But there is no open source version available. I think echopen can fill that gap.

Thanks
Winster

[kelu124]

Hi Winster,
If I understand well, you'd be using ultrasound as a carrier for data transfer (not for imaging) is that so? Out of curiosity, what is your career frequency -- and how do you modulate data?
Cheers
Luc

[winster]

Hello Luc,

Exactly, ultrasound is the carrier. After some research (and licensed libraries do so), frequencies somewhere between 15kHz and 18kHz seems ideal considering the device hardware support. And I think FSK modulation is the right way to go. Google has developed a library (not using NDK) way back in 2012 using ASK and I am working on that now, but its unsuitable in a noisy environment.

Regards
Winster

[benchoufi]

hi again Winster,

in fact the Android App is used mainly as display device. The I/O is image pixels in polar coordinates/image pixels in cartesian coordinate. In the future, we will put more and more calculus in the app - as for now the hard part of processing is hardware driven. But, in the perspective of further development, we are interested in what you're developing.

Regards,
nowami

[kelu124]

That's indeed ultrasounds for (medical) imaging, we're on MHz+ - so we're not really onto the same hardware neither. Would you have any page where you document your project ?

[winster]

Hello Nowami,

I thought the "Android App" is doing the receiver role. Is my assumption wrong?

Hello Luc,

My study is not in a shape yet to publish. But you can visit "https://code.google.com/archive/p/mobile-acoustic-modems-in-action/wikis/ProjectReport.wiki" which is what I follow for ASK

Regards
Winster

[benchoufi]

HI Winster,

The Android App is indeed in receiver role : all the data are processed in the hardware and then pixels are sent to the app and then are displayed Forthcoming development will consist in medical intended UX + GPU processing for the scan conversion algo (polar to cartesian transform). Sure, using GPU seems to be an overkiller choice, but we want in the future put more and more processing in the app

best regards,
nowami

[winster]

Hello Nowami,

Just to confirm, Is Android app receiving ultrasound waves from the hardware (This is what I mean by receiver - Ultrasound receiver)? This will at least do half the work for me.

Regards
Winster

[benchoufi]

Hi Winster, no, for the moment Android app receives image pixels data from transmitted by hardware. The latter collects the ultrasound raw data.

Regards,
nowami