Radar Signal Processing for Suppressing 2nd-trip Echoes under Existence of 1 st-trip Ground Clutters

摘要

Trade-off between range and Doppler ambiguity is one of the major problem to be considered in a meteorological Doppler radar. To mitigate this problem, phase modulation by a pseudo random code is often used. This method however degrades performance of removing ground clutter in the 1 st-trip echo region. In this paper, we proposed an improved method of 2nd-trip echo rejection that is compatible to ground clutter rejection in the 1 st-trip region. In this method, sequence of removing unwanted echoes in the 1 st-trip and the 2nd-trip region is changed in accordance with the intensity of the unwanted echoes in each region. The results of computer simulations indicate that the proposed signal processing method has a better performance of removing unwanted echoes than that of the conventional method in most situations of unwanted echoes.