Creates a 2nd order, proportional-plus-integrator (PPI) loop filter.

Parameters:¶

noise_bandwidth: float¶

The normalized noise bandwidth \(B_n T\) of the loop filter, where \(B_n\) is the noise bandwidth in Hz and \(T\) is the sampling period in seconds.

damping_factor: float¶

The damping factor \(\zeta\) of the loop filter. \(\zeta = 1\) is critically damped, \(\zeta < 1\) is underdamped, and \(\zeta > 1\) is overdamped.

K0: float = 1.0¶

The NCO gain \(K_0\).

Kp: float = 1.0¶

The gain \(K_p\) of the phase error detector (PED) or time error detector (TED).

Examples¶

See the Phase-locked loops example.