Re: [Discuss-gnuradio] USRP2 + WBX How to use a 32 MHz signal band?

[Josh Blum]

You should be able to setup an interpolating FIR filter to interpolate
by two and to shift your signal up or down by fs. Run each channel
though a filter (one up, one down) and add the resulting streams. The
resulting stream will have 2fs of bandwidth.

-Josh

On 12/02/2010 03:05 PM, Vladutzzz wrote:
> 
> NIck,
> What do you mean by "mix one sideband up and the other down"?
> How would that go?
> Thanks
> 
> Vlad.
> 
> 
> 
> Nick Foster-4 wrote:
>>
>> On Wed, 2010-12-01 at 13:53 -0800, Vladutzzz wrote:
>>> The problem is that I am in the middle of a project, time is of the
>>> essence
>>> and I don't have time to start stumbling around with UHD, right now I
>>> have
>>> to use Simulink, hence UDP. GnuRadio Companion still doesn't work with
>>> UHD,
>>> right (I am very new to python)?
>>
>> GRC has always worked with UHD. You might try downloading the latest UHD
>> and giving it a shot.
>>
>>> So no chance of UDP working with 2 USRPs at once, huh?!
>>
>> No.
>>
>>> Let me ask you something else then, if I manage to synchronize 2 USRPs
>>> working on separate computers to start sensing a band of 16MHz each, and
>>> their central frequency being 16MHz apart, saving those two bands in a
>>> file
>>> , what block (system of blocks) can I use to compose a 32MHz band (and I
>>> mean the whole band not just their power measurements) from the two 16MHz
>>> halfbands originating from the "From File" blocks?
>>> Naturally the samplerate of the new signal should be the double of that
>>> of
>>> the halfbands.
>>> If I just use a 2:1 multiplex the halfbands appear superimposed and the
>>> resulting signal band still occupies 16MHz.
>>
>> Assuming your signals are mixed to baseband you can interpolate both to
>> 32Msps and mix one sideband up and the other down so they sit where they
>> are supposed to, and then add the signals together. There's probably a
>> smarter (faster) way to do it.
>>
>> --n
>>
>>> Any ideas?
>>> Your help is really appreciated,
>>>
>>> Vlad.
>>>
>>>
>>>
>>> Marcus D. Leech wrote:
>>>>
>>>> On 12/01/2010 05:49 AM, Vladutzzz wrote:
>>>>> Thank you Marcus, for the very prompt and exhaustive reply!
>>>>> Mostly it's what I expected, but I am a wee bit worried about the IP
>>>>> addressing process:
>>>>> I need to change the IP of one of the USRP2 modules, how do I do that,
>>>>> considering I use an UDP FPGA image and not UHD?
>>>>> Also, what IPs should I use in the USPR2 source blocks, now that
>>> there's
>>>>> 2
>>>>> of them?
>>>>> Thanks!
>>>>>
>>>>> Vlad.
>>>>>   
>>>> My advice would be to screw up your courage, bite the bullet, and
>>>> convert to UHD.
>>>>
>>>> Theres a UHD utility, usrp2_addr_burner that can be used to change the
>>>> IP address.
>>>>
>>>> The factory address is: 192.168.10.2, you'll need to change it to an
>>>> address on a different
>>>>   subnet, like 192.168.20.2  or some such.  The idea is that you have
>>>> two GiGE ethernet ports,
>>>>   and you configure your system with the appropriate subnet on each
>>>> ethernet port, and program your
>>>>   USRP2 addresses accordingly.
>>>>
>>>>
>>>>
>>>> -- 
>>>> Principal Investigator
>>>> Shirleys Bay Radio Astronomy Consortium
>>>> http://www.sbrac.org
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> Discuss-gnuradio mailing list
>>>> address@hidden
>>>> http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
>>>>
>>>>
>>>
>>
>>
>>
>> _______________________________________________
>> Discuss-gnuradio mailing list
>> address@hidden
>> http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
>>
>>
>