A multi-stage approach is presented for efficient compensation of TWTA's nonlinear distortion (which belongs to Wiener systems) in wideband OFDM systems. In stages 1 and 2, TWTA's memory effects and memoryless nonlinear distortion are separately modeled, which leads to very fast modeling convergence. Then, TWTA's nonlinear distortion is completely compensated based on the models in stage 3.