Abstract:The Space Time Adaptive Processing (STAP) is a promising approach in the improvement of the wireless communication systems. Since it makes possible to reduce interferences ISI (Inter Symbol Interference) and CCI (Co-Channel Interference) but its disadvantage is the intensive treatment which reduces the speed of convergence of the algorithm LMS (Least Mean Square) and SMI (Sampling Matrix Inversion). Our approach resides in the use of a fast algorithm which calculate the weighting coefficients of the equalizer in frequential field with faster convergence.