In this paper, an 8-elment adaptive array,which based on non-linear decision feedback equalizer and recursive least square is introduced for the post 3rd Generation TDMA/TDD mobile communications. The forming of beam pattern is declared the performance of boosting up the desired directions and canceling down the interference directions. Then the relationship between training sequence and beam pattern convergence is analyzed. Computer simulation results show the affiliation of beam forming and the directions of arrivals. The best length of training sequence for bean convergence is found.