| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve detection accuracy in a device which detects division lines based on results obtained by sending and receiving electromagnetic waves. <P>SOLUTION: A string of differential strength data and a string of differential distance data are obtained by reading short-distance scan measurement data (strength data, distance data and scan angle) for one scan and by differentiating each read strength data string and distance data string (S110 to S120). Data areas with continuous positive levels or negative levels and between two null levels are extracted from the differential strength data string as candidate areas (S130). From the extracted candidate areas, areas in which levels of the differential distance data string vary from positive to negative and to positive (in the case of a first scan areas) or from negative to positive and to negative (in the case of a second scan areas) in portions corresponding to the candidate areas, are extracted as object areas in which reflection from the division line is obtained (S140). <P>COPYRIGHT: (C)2012,JPO&INPIT |
