In multisensor tracking system, the center processor receives the out-of-sequence measurements (OOSMs) because of communication time delays. An optimal and sub-optimal interpolation filter for filtering out-of-sequence measurements with arbitrary lag was proposed. The detailed implementation steps of OOSM processing scheme based on OOSM-interpolation filter (OOSM-IF) is deduced. The performance estimates of the OOSM-IF obtained for ground moving target indicator (GMTI) is compared with similar performance estimates obtained from the OOSM extend Kalman filter (OOSM-EKF). The comparison of the simulation results shows that the presented algorithms enhance the estimation accuracy for nonlinear out-of sequence measurement.