Hi,

Does anyone have any experience of the multiply by 4 carrier recovery
method. Without RRC filters at the modulator, I can recover the
carrier no problem at the receiver and the phase stay constant.
However, when I introduce RRC filtering in the modulator, I cannot get
the recovered carrier to stay in phase. The bottom two links show what
I am getting. Has anyone been down this road before and can offer any
advice?


http://i248.photobucket.com/albums/gg170/stenasc/carrier_recover2.jpg

http://i248.photobucket.com/albums/gg170/stenasc/carrier_recover1.jpg

Many Thanks
Bob