Re: [Discuss-gnuradio] Costas loop in HRPT receiver

[Tom Rondeau]

On Fri, May 16, 2014 at 12:00 PM, Pablo Fernández Alonso <address@hidden> wrote:

Hello,

 

I’ve heard about costas loop to obtain the carrier of a PSK signal. But I don’t know how it is implemented the carrier recovery in the hrpt example of gr-noaa in order to demodulate the BPSK signal. I would appreciate some help with this topic.

 

Regards,

 

Pablo.

Pablo,

The Costas loop is implemented using a standard second-order control loop, which means it tracks the phase and the phase change (frequency). You can find more about how these loops here (and in plenty of text books on phase locked loops and such):

http://www.trondeau.com/blog/2011/8/13/control-loop-gain-values.html

Tom