USRP-1 and 4ch receiver?

GNU Radio
1

Mr. Marcus Mueller,

Thank you very much for suggestions. I have some more questions.

  1. I searched for the GNU Radio mailing-list archive and found a
    discussion

Subject: [Discuss-gnuradio] USRP1 4 Channel Subdev Issue
Date: Tue, 19 Feb 2013 11:07:55 -0800 (PST)

Then it would be possible to organize a 4-ch RX with USRP-1. (Some
limitation is reported here, too.) But as you suggest, we can use only
real (one) input for each frequency. Also I need to prepare the
downward frequency conversion by our selves. Careful additional
hardware design is necessary. I know this is not easy.

  1. Your suggestion of “2 x B210” is very interesting. A good thing is
    that the frequency conversion is included in the board. But I want to
    know how to run 2 USRP boards from one application program. Is there an
    example? If possible I want to use GNU Radio Python code, but is this
    possible? If not, do we need to control from C++? In my application
    “phase coherency” across all inputs are necessary. “timing
    synchronization” is not necessary.

  2. One more question. If 2) is possible, is it possible to run “2 x
    USRP-1” from a single application on a single PC?

Regards,

–
Mamoru Y. / RISH, Kyoto University
[email protected]
Phone +81-774-38-3814, Cell +81-90-5653-7555

On 2014/08/08 1:00, [email protected] wrote:> Message:
8 Date: Thu, 07 Aug 2014 09:41:38 +0200 From: Marcus M?ller

2

Hey Mamoru,

On 09.08.2014 21:17, Mamoru Y. via USRP-users wrote:

  1. Your suggestion of “2 x B210” is very interesting. A good thing is
    that the frequency conversion is included in the board. But I want to
    know how to run 2 USRP boards from one application program. Is there an
    example? If possible I want to use GNU Radio Python code, but is this
    possible? If not, do we need to control from C++? In my application
    “phase coherency” across all inputs are necessary. “timing
    synchronization” is not necessary.

This is, in general, possible. For some devices (e.g. N210), you can
spawn a USRP Source/Sink that will talk to several devices, and allocate
channels accordingly (e.g., channel 0 -> device 1, channel 2 -> device 2
etc.). With B210, you simply create a USRP source for every device you
have. If they are both connected to the same clock source, you have
synchronized receivers.

  1. One more question. If 2) is possible, is it possible to run “2 x
    USRP-1” from a single application on a single PC?

You can also create two USRP Sources, one for each USRP1. However,
unlike N210 or X310 for example, you can’t synch them through software.
Use the “serial=XXX” or “name=XXX” device addrs to address these.

M