Initialization of a first or second order loop filter for use in a carrier recovery PLL
Time constant, in samples
Loop bandwidth, normalized to sample frequency
Damping factor
Returned loop filter object
The returned object can be used as a component in a carrier recovery process
(see carrier_rec_init), or directly with the process
method.
A first order loop can recover and track the carrier phase (and the carrier frequency is supposed to be low compared to the symbol rate).
A second order loop can also recover and track the carrier frequency.
wf = wf_init('bpsk'); lf = lf_init(1, tc = 10); // First order loop filter // lf can be used now with carrier_rec_init | ![]() | ![]() |
DVBS2 : Carrier phase synchronization techniques for broadband satellite transmissions, ESA, 2003