Difference between revisions of "PLL Carrier Tracking"

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[[Category:Block Docs]]
 
[[Category:Block Docs]]
Implements a PLL which locks to the input frequency and outputs the input signal mixed with that carrier.
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Implements a Phase Locked Loop (PLL) which locks to the carrier of the input frequency and outputs the input signal mixed with that carrier.
  
This PLL locks onto a [possibly noisy] reference carrier on the input and outputs that signal, downconverted to DC
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This PLL locks onto a [possibly noisy] reference carrier on the input and outputs that signal, downconverted to DC.
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=== Notes ===
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* <b>Important:</b> The frequency parameters below are in <i>radians per sample</i> rather than Hz.
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** for example:
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*** input centered at 0 Hz.
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*** Sample rate = 48kHz.
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*** frequency variations to track +- 500Hz.
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*** Max freq = 0.0654
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*** Min freq = -0.0654
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* This block requires an input signal of at least -30db in order to lock to the carrier.
  
 
== Parameters ==
 
== Parameters ==

Revision as of 13:25, 28 October 2019

Implements a Phase Locked Loop (PLL) which locks to the carrier of the input frequency and outputs the input signal mixed with that carrier.

This PLL locks onto a [possibly noisy] reference carrier on the input and outputs that signal, downconverted to DC.

Notes

  • Important: The frequency parameters below are in radians per sample rather than Hz.
    • for example:
      • input centered at 0 Hz.
      • Sample rate = 48kHz.
      • frequency variations to track +- 500Hz.
      • Max freq = 0.0654
      • Min freq = -0.0654
  • This block requires an input signal of at least -30db in order to lock to the carrier.

Parameters

(R): Run-time adjustable

Loop bandwidth (R)
The loop bandwidth determines the lock range and should be set around pi/200 2pi/100.
Max freq
Maximum frequency of the carrier in radians per sample
Min freq
Minimum frequency of the carrier in radians per sample

Example Flowgraph

This flowgraph shows the use of a PLL Carrier Tracking block in an AM receiver.

FunCube AM.png

Source Files

C++ files
TODO
Header files
TODO
Public header files
TODO
Block definition
TODO