Re: Use Xilinx DDS for carrier recovery

On Thu, 19 Feb 2009 19:27:24 -0600, "billykao" <billy.kao@xxxxxxxxx>
wrote:

I am working under Xilinx System Generator and using Xilinx DDS for
BPSK
carrier tracking. Xilinx DDS can take either phase increment or phase
offset as the input. If my phase detector is able to find the phase
error
as the following figure. How can I use the information to control
Xilinx
DDS to track carrier frequency and phase?

phase err
| /| /|
| / | / | . . .
| /_ |/_ |_________t

Create a Phase Locked Loop with your detector and the DDS. You'll
likely want a loop filter in between them.

Eric Jacobsen
Minister of Algorithms
Abineau Communications
http://www.ericjacobsen.org

Blog: http://www.dsprelated.com/blogs-1/hf/Eric_Jacobsen.php


The DDS only take phase increment/phase offset and not both. I can
calculate the frequency from the phase. So, if I have a loop filter
between phase detector and DDS, what should I use to control DDS?

For example, if my delta(F) is 2 KHz with phase offset, how can I operate
the DDS to lock to the carrier? Thank you.

.

Relevant Pages

  • Re: Use Xilinx DDS for carrier recovery
    ... likely want a loop filter in between them. ... The DDS only take phase increment/phase offset and not both. ... between phase detector and DDS, what should I use to control DDS? ...
    (comp.dsp)
  • Re: PLL confusion
    ... >>typically a sine or triangle wave) if they are really different. ... >loop then try to bring the dc level to zero or is matching frequencies ... But if you add an integrator in the path from the phase detector ...
    (sci.electronics.basics)
  • Re: Phase Locked Loop Phase Shift
    ... I'm trying to design a PLL frequency multiplier which will track a ... I've got an LM565 phase locked loop and have built a circuit which has ... signal and am generating a 12.8khz clock which is synchronised to the ... It isn't the multiplying phase detector that's at fault, ...
    (sci.electronics.design)
  • Re: ntpd PLL and clock overshoot
    ... representation, the digital NTP loop behaves as an analog loop, at least ... The initial frequency estimate measures only the frequency offset; ... whereas it has converged faster in earlier implementations of ntpd. ... client have been computed between the local system time and a GPS PCI card ...
    (comp.protocols.time.ntp)
  • G-Code Liberries II/How the cadcam-less survive XXLVII: The E-word as a counter
    ... First, if just drilling, the macro issue is fairly moot, because you can put ... explicitly do the milling at each X,Y offset. ... Because inherent in the macro loop is a *constant counter* or increment, ... There is no way for a macro incrementing a *coordinate word* to ...
    (alt.machines.cnc)