Wednesday, July 1, 2009

iPhone teaser ...

I got a little side tracked this week playing with the iPhone SDK. I wanted to see if I could get something working that will, at a minimum, display the spectrum for the currently selected frequency so that I could monitor HPSDR remotely using my iPhone.

This is some prototype code running on the iPhone Simulator (it does run on my iPhone as well). It is updating the display 15 times per second. The data is currently 2 seconds of spectrum samples (30*4096 samples) that I captured using ghpsdr and wrote them to a file that are repeated while the application runs.

Next step is to add the ability to ghpsdr to write them to a socket connection and add the code to the iPhone to make a socket connection to ghpsdr.


video

3 comments:

Dave said...

Interesting. I have wondered if the iPhone could be used as a PSK31 receiver display and code generator for a low power SDR transceiver for Ham Radio

John said...

Hi Dave,

Interesting idea.

I now have a network connection working to my ghpsdr software that will display the spectrum on the iPhone. Currently this is just sending over the power spectrum. I plan to see if I can send over the raw I/Q samples and perform the FFT on the iPhone itself.

I am also looking at the audio interface to read from line-in on the iPhone to see if I can get a simple receiver working using a Softrock.

I am not sure what the iPhone is capable of, but so far it is looking interesting.

Dave said...

Well good luck with the project. I think the iPhone or G-phone are great platforms for future HAM radio projects.

The displays are pretty good size and the overall size/battery life make them useful.