🚀 go-pugleaf

"Witek" <robertwi@polbox.com> wrote in message news:<9lmo8i$rep$1@news.tpi.pl>...
> Excuse me , but I do not write well in English language.
> I must recover data from signal modulated GMSK.
> From devices which one I possess goes out stream I&Q from analog to digital
> converter.
> How from this of stream to reproduce digital data?


If you have a coherent detector, for both I and Q branches you
demodulate, low pass filter, integrate then add the two outputs of the
integrtors. I am just writing this from looking at a diagram. It is on
page 266 of Wireless Communications by T. Rappaporte. There are a few
timing phase shifts: obviously the pi/2 phase shift to the Q branch
with respect to the I branch. There is a pi/2 phase shift from the
output of the symbol timing recovery circuit to the input signal of
the loop filter for carrier recovery, this pi/2 is multiplied by the
output of the product of the two carriers. There is a pi phase shift
for the Q branch with respect to the I branch for symbol sample timing
from the symbol timing recovery circuit. And that's about it. I would
draw a diagram if I were you but I wouldn't guaruntee my description
has been that good so if you can get the book I mentioned I would get
that.

Steve