Phase error dynamics of a class of modified second-order digital phase-locked loops in the background of cochannel interference

The present paper examines the dynamics of a nonuniform sampling second-order digital phase-locked loop (NUS-DPLL) with an effectively modified loop filter. Through an analytical study of the system response around the steady state, supported by detailed simulation results, the paper establishes the better performance of the modified DPLL. It has been shown by a simulation study as well as explained qualitatively, that the modified DPLL will be able to withstand the adverse effects of cochannel interference signals better than the conventional NUS-DPLL.