Abstract: Digital phase-locked loop is currently the most commonly used carrier tracking technology. In order to improve the carrier tracking performance, Kalman filter tracking methods have been widely studied. However, the design parameters of these two methods are completely different, which makes it difficult to compare the tracking performance. To solve the problem, the relationship between the error feedback model of Kalman filter tracking and digital phase-locked loop is established by simplifying the processing of innovation and local carrier frequency, and the analytic expression of the equivalent loop bandwidth of Kalman filter tracking is derived. The conclusion can be used for the parameter design of Kalman filter tracking and make accurate compare between the two types of tracking algorithms.