Radar is an instrument that increases our ability to see and record the surrounding nature. This ability to see is not hindered by darkness, fog, haze, rain, snow or smoke, all of which limit human sight. We observed a car carrier using a millimeter wave radar with frequency of 34.86GHz, horizontal beam width of 0.25°, vertical beam width of 5.0°, horizontal linear polarization, antenna scan rate of 20RPM., pulse width of 30 nano second and transmitted peak power of 30KW. A Target was embedded in sea clutter, the discrimination between target and sea clutter was very difficult on a plan position indicator (P.P.I.). In order to improve possibility of detection on target in the presence of sea clutter, the amplitude statistics of target and sea clutter were examined in relation to the thresholdmethod. It is shown that target and sea clutter amplitude obey a normal distribution, from which the probability of detection and the false alarm probability were calculated theoretically and experimentally. From this, the shape of the vessel was easily recognized. To improve a target to clutter (T/C) ratio, we used a two-pole filter which is described mathematically by y(i)=φy(i-1)+Γx(i) where [numerical formula] where x(i) is the input at time i, y_1(i) is the intermediate calculation at time i, y_2(i) is the output at time i and k_1 and k_2 are the two feedback values. Suffix i means signal of i-th sweep line. Output of each point on current sweep is given by processing with same point on previous (i-1) th sweep line. Finally, we improved by T/C ratio of 1.7(dB), compared to raw data.
