Re: [Discuss-gnuradio] USRP examples

[Eric Blossom]

On Thu, Jul 21, 2005 at 05:48:33PM +0530, Arora_Amit wrote:
> Hi all,
>
> We are working on USRP. Please can any let us know what the
> factors or on what basis the audio_decimation, if_freq, usrp_decim.

These values are choosen so that the sample rates through the
processing path "make sense".  The USRP can sample and decimate at
particular rates.  The audio sink/source can sample at particular
rates.  We generally pick ratios such that they are related by simple
integer factors and that the signals of interest have appropriate
bandwidth at various points in the signal processing chain.

The API for using and controlling the usrp is documented in 
usrp/host/lib/usrp_basic.h and usrp_standard.h

> It will be help if we can get what the following mention programs does:

> 1.    usrp_fft_simple.py

Does the same thing as usrp_fft only with less gui cruft.
(Plots Fast Fourier Transform of samples received from USRP.)

> 2.    benchmark_usb.py 

An unreliable program to detemine maximum bandwidth of USB

>From the comment at the top of the file:

  Benchmark the USB/USRP throughput.  Finds the maximum full-duplex speed
  the USRP/USB combination can sustain without errors.

> 3.    usrp_oscope.py

Digital oscilloscope that uses a USRP as the source of samples.

> 4.    dbs_debug.py  

Program to assist in debugging the DBS_RX daughterboard.

The DBS_RX daughterboard is a receive-only daughterboard that covers 
800 MHz to 2400 MHz.

> 5.    nbfm_ptt_quick_and_dirty.py 

Removed from CVS.  See nbfm_ptt.py  Narrow Band FM "Push to Talk" (wakie-talkie)

> 6.     usrp_rx_cfile.py

Read samples from the USRP and write to file formatted as binary
single-precision complex values.

> 7.    dbs_fft.py

Removed from CVS.

> 8.    nbfm_rcv.py  

Narrow Band FM receiver.


If you haven't already, I suggest that you spend some time with:

  http://www.gnu.org/software/gnuradio/doc/exploring-gnuradio.html
  http://www.gnu.org/software/gnuradio/doc/howto-write-a-block.html


Also, there are online docs for the C++ guts:

  http://www.gnu.org/software/gnuradio/doc/index.html


Eric