Re: [Discuss-gnuradio] May I use GUN Radio without USRP

[Josh Blum]

> I want to know may I use GNU radio without USRP.

Of course! Gnuradio can be a stand-alone simulation environment. And you 
can interface it with anything that you can write code for.

GNU Radio is...

    * An API for creating signal blocks (C++/Python)
    * A runtime environment for signal processing
    * A library of signal processing blocks
    * User scripts and applications
    * Hardware drivers (USRP/USRP2)
    * An application for creating flow graphs (GRC)

> I mean Since USRP is just used for transiver, ADC/DAC,  converting RF signal to
> baseband and transmitting baseband signal to GNU Radio for processing, then may
> I produce baseband workload by an Agilent baseband signal generator or even
> Matlab, and then connect GNU Radio with signal generator or Matlab?

If you can write code in some language to acquire samples from lab 
equipment, then you can write a custom gnuradio block for that 
equipment. :-)

> The reason I am thinking about this is that from some analysis, I find the data
> rate of the USB2.0 bus limits the bandwidth of the base band signal to 8 MHz,
> which is not enough for my project. And My focus is just baseband signal
> processing, I want to save money on USRP if I can use existing equipments in the
> lab.


Can you test your application at lower data rates? Its usually a good 
idea to see that

1) you can implement the processing in simulation in the gnuradio 
environment
2) you can run the processing at a low rate on a platform like the USRP
  2a) prove that the CPU can keep up at lower rates
  2b) prove that the algorithm works in the presence of noise and 
frequency offsets

So usrp can be a valuable part of your RF development even if you must 
replace it with a higher rate/more expensive device for delivery. Is the 
extra time spent integrating agilent equipment worth it if you find out 
that your algorithm cant run in real-time at lower usrp rates?

Hope that helps!
-Josh