A novel digital phase-tracking and measuring loop(DPTML) appropriate for distance measurement are proposed and analyzed using the theory of finite Markov chains.The performance of steady-state phase-tracking error and phase acquisition time in the presence of additive band-limited white Gaussian noise are evaluated.By analysis of the noise-resistant characteristic of the key module

guidelines on selection of its pivotal parameter are given.A new method utilizing the acquired steady-state results to ulteriorly reduce the tracking error is also presented.Both the calculated and simulated results indicate that the DPTML has much less steady-state error than traditional zero-crossing digital phase-locking loop(ZC-DPLL).Additionally

because the "hangup" effect leading to prolonged phase transients owing to the presence of the dead zone around π rad is thoroughly eliminated

the phase acquisition time of the DPTML is much shorter than the latter

especially in high SNR.