Re: [Discuss-gnuradio] G U Radio Companion : Implementing DQPSK modultation

[Martin Braun]

On Sun, Feb 06, 2011 at 01:58:17PM -0500, Steven Clark wrote:
> On Sun, Feb 6, 2011 at 1:34 PM, Varun Krishnamurthy <address@hidden>
> wrote:
> 
>     Hi ,
> 
>     I am new to GNU Radio and am facing difficulties in implementing DQPSK
>     modulation on Gnu Radio Companion. The system works fine , but for one
>     small glitch. The DQPSK modulator/demodulator's input and output are in
>     Byte format, which makes it a little hard to comprehend the output.
> 
>     for eg : if the input is 00100001. 
> 
>     The o/p of the demod is as follows : 00000000 00000000 11111111
>     00000000 00000000 00000000 00000000 11111111  (instead of 00100001).
> 
> 
>     I would be really grateful if a way around this can be told.
> 
> I believe this is what the block unpacked_to_packed is for.

Also, you should check why your demod outputs eight 1's instead of one.
And don't forget to include a preamble or something like that in your
transmission, otherwise you won't be able to figure out which symbol
maps to which bit, and the packed bit stream will actually be less
informative than the unpacked one.

MB

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