| 摘要 |
<p>PURPOSE:To display a target at the same strength of the target having the same effective reflecting area by setting the threshold value when radar video undergoes A/D conversion at the value, which is inversely proportional to the four-time multiplication of the distance. CONSTITUTION:A threshold-value control circuit is provided. The threshold value stored in a memory 42 is the absolute value of the threshold value, which is inversely proportional to the four-time multiplication of the distance, refered with the counted value of a distance-coefficient counter 41 and outputted into a D/A converter 43. The value is converted into the analog signal and supplied into an adding circuit 44. In the adding circuit 44, the analog signal, which indicates the logarithm value of the threshold value set with the threshold-value setting circuit, is inputted. Both inputted values are added in the adding circuit 44. The value of the resultant analog signal changes in the inverse proportion to the four-time multiplication of the distance. The characteristic with respect to the distance changes with the setting with the threshold-value setting circuit. The A/D conversion in the A/D converter is executed by using the threshold value.</p> |
