A dynamic simulator of the reticle seekers has been developed to predict the tracking performance in various engagement scenarios. We can analyze the performance of the infrared (IR) reticle seekers with various positions of targets in the field of view, with several signal-to-noise ratios. We have shown that the presented simulator is a very powerful means for developing the signal processing algorithms in the presence of infrared countermeasures (IRCM). A simple and efficient algorithm for infrared counter-countermeasures (IRCCM) is proposed and simulated. With the incorporation of this IRCCM technique into the reticle seeker in the presence of IRCM, the missile can intercept its target successfully.