We propose a numerical method based fusion technique namely quasilinearized iterative method (QLT) to obtain a monotone sequence of iterates, converging. This is obtained with track to track association (T2TA) using Log-likelihood ratio test, based on the Neyman-Pearson criteria. Kalman filter (KF) is used to smooth the associated and fused track. Simulated results show that the proposed fusion method follows the actual track with some bias, whereas conventional state vector fusion (SVF) method is not able to give consistent results in following the actual track. © 2014, Research India Publications.