Abstract: For solving the influence of the heterogeneous scattering features of area target and the acceleration in velocity measuring of CW radar for landing navigation，a high-accuracy beam center velocity measuring method was presented.Kalman filter was used for velocity tracking and acceleration compensation after acceleration estimating.ZFFT transform was used for spectrum zoom of target Doppler range.Finally the envelope method was presented for high-precision estimating of beam center velocity.The simulation results verify that the envelope method can obtain higher estimating precision and adaptation than other methods，the standard deviation（3δ）of velocity measuring error is less than 0.15m/s.The process time analysis results of hardware system verify that the algorithm procedure is suitable for real-time processing，and has been successfully used in certain landing navigation radar system.

Key words: landing navigation, continuous wave, acceleration compensation, ZFFT transform, spectrum zoom, Kalman filter, beam center velocity, envelope method