Super cool! One of my labmates has been playing around with SDR and I was thinking that Julia would be great for that. Please bring a demo to JuliaCon!
-s On Mon, Apr 20, 2015, at 12:14 PM, Miguel Bazdresch wrote: > I'm using GnuRadio on Ubuntu mainly. I may not have a chance to try it > out until the summer, though. On a somewhat related note, something > that I also want to tackle when I have some time is a julia interface > to the UHD, so that we can control the radios directly from Julia. > > -- mb > > On Mon, Apr 20, 2015 at 11:37 AM, Jay Kickliter > <jay.kickli...@gmail.com> wrote: >> Thanks. What OS are you using, and how did you install Julia/GNU >> Radio? I'll attempt to fix any major problems before you try it out. >> >> On Monday, April 20, 2015 at 9:33:18 AM UTC-6, Miguel >> Bazdresch wrote: >>> >>> This is great, and something I wanted to do but hadn't had time for. >>> I'll give it a try when I have a chance. >>> >>> >>> On Mon, Apr 20, 2015 at 10:22 AM, Jay Kickliter >>> <jay.ki...@gmail.com> wrote: >>>> I just pushed a rough draft gr-juliaffi[1] to GitHub. It is not a >>>> Julia package, but a GNU Radio module (C++/Python) that calls your >>>> Julia code to do the actual signal processing. >>>> >>>> If you're not familiar with GNU Radio, it is a software defined >>>> radio (SDR) framework. SDR is really cool. Traditional radio >>>> hardware is dedicated to certain kind of signal (like a satellite >>>> modem or FM receiver). SDR lets you use generic hardware that does >>>> little more than digitize the raw radio waves and send them to a >>>> computer. From there, all the signal processing is performed in >>>> software. There are real world applications[2] of SDR. I use it >>>> almost every day. >>>> >>>> The motivation for this block came recently when I needed something >>>> GNU Radio didn't have yet. At my job, we're developing new 802.15.4 >>>> hardware. There is an 802.15.4[3] out-of-tree module for GNU Radio, >>>> but it's not complete and doesn't have the capability of >>>> de-spreading[4] 802.15.4 900 MHz BPSK signals. I wrote code to >>>> de-spread the signal in Julia, and piped from/to GNU Radio using >>>> ZeroMQ. That works fine, but it's cumbersome. Why not just have GNU >>>> Radio call the Julia code directly? >>>> >>>> If you do want to use the module, please let me know what issues >>>> you run into when building/using it. I spent two solid days just >>>> trying to get cmake to find and properly set up linking to >>>> libjulia. I'm using OS X, and @rpath was causing the biggest >>>> problem for me. It only built when I finally stopped trying to tell >>>> cmake where to find libjulia and switched to find_library. Also I >>>> had to do an actual `make install release` in the Julia repo for >>>> all the headers and libraries to be in predictable locations. >>>> That's because the FindJulia cmake module I added calls julia on >>>> the command line to figure out where stuff is. The code still >>>> crashes if I try to run it with `jl_init(NULL)[5]'. >>>> >>>> There's still more c++ work to be done, and I don't know c++. I >>>> just infinite monkey it 'till it works. I just hope I or someone >>>> else can figure out how to make the c++ configure itself >>>> dynamically, so it isn't necessary to define blocks for every combo >>>> of input/output type. Most of the repo was automatically created >>>> with gr_modtool. This file[6] is pretty much the whole project. >>>> It's definitely possible to change the number of inputs/outputs to >>>> block at runtime. Looking at the code, I think it may be possible >>>> to change the type as well. >>>> >>>> I was hoping have this done with some good examples in time to give >>>> a JuliaCon talk. Maybe next year. I'll be there anyway, if anyone's >>>> interested I'll give an informal demo. >>> > Links: 1. https://github.com/JayKickliter/gr-juliaffi 2. http://www.fsf.org/blogs/community/free-software-in-space-gnu-radio-and-the-isee-3-spacecraft 3. https://github.com/bastibl/gr-ieee802-15-4.git 4. http://en.wikipedia.org/wiki/Direct-sequence_spread_spectrum 5. https://github.com/JayKickliter/gr-juliaffi/blob/master/lib/juliablock_ff_impl.cc#L47 6. https://github.com/JayKickliter/gr-juliaffi/blob/master/lib/juliablock_ff_impl.cc
