[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Discuss-gnuradio] reg. PSK Mod Block in Gnu radio
From: |
Tom Rondeau |
Subject: |
Re: [Discuss-gnuradio] reg. PSK Mod Block in Gnu radio |
Date: |
Tue, 11 Jun 2013 09:38:51 -0400 |
On Mon, Jun 10, 2013 at 7:25 PM, vamshi krishna dodla
<address@hidden> wrote:
> http://gnuradio.squarespace.com/storage/tutorial/rondeau-costterra2.pdf
>
>
> Hi all, why does the output of PSK Mod block is imperfect, compared to
> theoritical QPSK constellation.( iam implementing qpsk with 4 sampl/sym and
> 4 constellation points).The experiment im doing is the same in link
> (http://gnuradio.squarespace.com/storage/tutorial/rondeau-costterra2.pdf).
>
>
> --
> Thanks & Regards
> Vamshi Krishna.
Inter-symbol interference. Look up the root raised cosine filter and
you'll see why. Basically, an RRC is /not/ a Nyquist filter. Now think
about what that means to the receiver.
Tom