Research on the Influence of Phase Discriminator on Costas Tracking Performance

PLL (phase-locked loop) is widely used in radar, navigation equipment and space technology, affecting the performance of the device directly. It´s essential to study parts of the PLL to improve the performance of PLL. PD (Phase discriminator) is a kind of phase comparison device, its performance directly affects the performance of the entire loop. This paper studies PD from four aspects of calculated amount, convergence range, phase gain and phase error. Then studies the influence on capture time and tracking accuracy and gives the theoretical explanation. Finally, an evidence for the selection of phase discriminator under different CNR is provided.