Re: [Discuss-gnuradio] Hello GNURadio from the Amateur Radio World

[Marcus D. Leech]

On 05/26/2018 09:44 PM, Dan CaJacob wrote:
> Will,
>
> I think you will find a wide variety of real-world applications 
> GNURadio has been used for. For myself, that includes ground to space 
> and space to ground communications systems, encompassing both common 
> desktop machines as well as embedded processors and FPGAs. Certainly 
> it is easier to write a modem for a desktop CPU, but a good C++ 
> developer (I am not one, but I work with them) can take advantage of 
> pipelined operations in both embedded and desktop CPUs to make 
> distinction between the platforms less crippling. The Volk project 
> even makes this win more or less free (no need to write your own 
> instrinsics) if you profile it for your specific embedded device.
>
> That said, I notice a lot of people new to GR wanting to jump right 
> into doing something hard on a Raspberry Pi or similar SBC. I think 
> you'll find that's generally a mistake. I'd suggest getting 
> comfortable with GR and SDR on the desktop before moving on to 
> embedded systems, because there's a lot to learn in both and it's 
> going to be worse if you have to learn them both at the same time.
>
> - Dan
Another thing I find is that there's a big gap in comprehension about 
how much 'stuff' happens to each and every sample for even relatively simple
  (from a 10kft view) DSP flows.

"My CPU runs at 2.5GHz, and I'm only bringing in a measly 10MHz, why is 
this not working for me?"

"Why can't I make a precipitously-steep filter--this is software, after 
all.  It's all kinda virtual, right?"

Folks who are coming at this from the "apps" world may never have 
considered or experienced or pondered exactly what happens inside
  the "sausage factory" we call a modern operating system. 
"Sample-arrives---->[MAGIC]----->it's in my app---->[MORE 
MAGIC]---->cool stuff happens".

If you're coming from a world where real-world "events" happen at the 
rate of user-clicks, thinking about being responsive to "events" that may be
  happening millions of times per second may be a bit of a cognitive 
shock...

Just random thoughts from years and years watching this ballet play out....