Re: [Discuss-gnuradio] bladeRF - gr-osmosdr - gqrx - bandwidth?

[Brian Padalino]

On Fri, Sep 13, 2013 at 2:19 AM, Ralph A. Schmid, dk5ras
<address@hidden> wrote:
> Hi,
>
> I am using bladeRF with gr-osmosdr, gnuradio 3.7 and gqrx, so far a fine
> radio. One thing, when using gqrx...I am limited to USB2.0 at the moment, so
> I use a sampling rate of 8 Ms/s, and in this mode I have big problems with
> images from the neighbour frequencies that are still within the 26 MHz
> bandwidth, or whatever the maximum BW is.
>
> Is there some command to set this bandwidth to a smaller value? I assume
> that this would improve my RX experience a lot :) A quick look at osmocom
> showed me nothing, but maybe I missed smth.

The gr-osmosdr interface allows for a bandwidth setting to be changed here:

  http://cgit.osmocom.org/gr-osmosdr/tree/lib/bladerf/bladerf_source_c.cc#n581

The driver will figure out which bandwidth is closest to what you want
with a minimum of 1.5MHz and a maximum of 28MHz for the low-pass
filters.

It will definitely make a world of difference by actually applying the
LPF and removing the aliasing.

As for official support for gqrx, it's next on our list.  We need to
get on the gqrx mailing list and figure out what code we need to
write.

Brian