PLL Carrier Tracking

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.

Source Files

C++ files

TODO

Header files

TODO

Public header files

TODO

Block definition

TODO