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Re: [Discuss-gnuradio] need help for digital.constellation_decoder_cb in
Re: [Discuss-gnuradio] need help for digital.constellation_decoder_cb in release 3.5.0
Fri, 9 Mar 2012 11:50:05 -0700
On Thu, Mar 8, 2012 at 8:19 PM, Arturo Rinaldi <address@hidden> wrote:
> Nella citazione in data ven 09 dic 2011 05:55:57 CET, Ben Reynwar ha
>> On Thu, Dec 8, 2011 at 5:33 PM, Arturo Rinaldi<address@hidden>
>>> I noticed dramatic changes in the 3.5.0 release in the generation of the
>>> constellation points of digital modulations. So, if the easy part is to
>>> again modify the source code to match my needs, i need some help in using
>>> the new block :
>>> instead of
>>> I usually used the last one where arg1 is a list containing the complex
>>> values of a generic digital modulation and arg2 is the symbol mapping
>>> Coding for instance). Which blocks do i need to put together to get the
>>> result ?
>>> Regards, Arturo
>>> Discuss-gnuradio mailing list
>> Simplest solution is probably:
>> constell = digital.digital_constellation(list_of_complex_points, , 1, 1)
>> decoder = digital.constellation_decoder_cb(constell)
>> To get the symbol mapping you want, just choose the appropriate order
>> of the complex points in the list.
>> The 2nd, 3rd and 4th arguments to the constellation constructor while
>> not relevant to this example are:
>> - a mapping to be applied before differential encoding.
>> - the rotational-symmetry of the constellation
>> - the dimensionality of the constellation (i.e. number of complex
>> points that together map to one symbol)
>> Functions to simplify the creation of commonly used constellations can
>> be found in digital.bpsk, digital.qpsk, digital.psk, and digital.qam.
> i made some progress in simplyfing the creation of the constellations but i
> still need help in the decoding part.
> I'm trying to calculate the modulation BER by using this flow graph :
> i removed all the unnecessary parameters to my study (excess bw ,
> differential coding etc.) because i need only gray coding. and the decoding
> part is this one
> could you please help me ? the grc blocks are made by invoking only the
> psk_new.py source
> modified by me. please help me. thx in advance
> Regards, Arturo.
I'd be happy to help but I'm not quite sure what exactly your
Maybe you could post the python generated by grc, along with the issue