Abstarct: One of the important topics in electronic warfare debates is to counter tracking radars and radar guided surface-to-air and air-to-air missiles, recognition and using electronic counter measures correctly baxsed on jamming techniques.Most mathematical modeling of airborne jammers have been made on stand-off jamming, or stand-in jamming which are two types, self protection jamming or escort jamming and no computation is available for expendable jammer threats. In this thesis to evaluate the performance of expendable jammer against the threats, according to threat recogniton by radar warning receiver and determine its type, at first, eight threats from four different frequency bands, S, C, X and Ku have been considered and then the effects of expandable jammers against them have been simulated and analyzed. simulation results showes that For a threat like the Amraam missile within 12Km, the duration 10.27s is jamming.