| 摘要 |
<p>PURPOSE:To make the detection range constant from a vehicle which mounts a radar equipment to a target regardless of whether the target is large or small by reducing the vertical beam angle of a radar antenna and causing the beam of a transmit radio wave to produce an elevation on the whole. CONSTITUTION:When a vehicle 4 approaches a vehicle 14 which runs as shown by an arrow A from behind and enters the range of detection range L, a transmit wave radiated from the radar antenna 16 strikes the vehicle 4 and its reflected wave is received by the radar antenna 16 to be displayed on a display means. Then, the driver on the vehicle 14 knows that the following vehicle approaches and monitors the rear of the vehicle 14. The beam center 17 of the transmit wave is at a constant elevation angle theta2, so the approach is detected within nearly the same range of the detection range L regardless of whether the vehicle is large of small. Therefore, it is possible to detect the target approaching the vehicle 14 from behind within the range of the constant range, and the rear monitoring function of the radar device is improved to evade danger such as a collision securely.</p> |
