Abstract: The low orbit space object's attitude movement's modulation to narrow-band echo(impulse) signal is analyzed.It shows that low orbit space object's narrowband signal's phase contains much more important features than its magnitude.Wavelet is applied to detect long-term evolution of the movement from the phase of narrow-band signal and to identify the low orbit space object's sketchy types.Experimentation with a great deal of real measured data proves that it be useful in(identifying) the low orbit space object's sketchy types.