Shigeaki Nishikawa, Hiroshi Endo
There is considerable public and private support for intelligent transport systems (ITS), which promise spectacular improvements in road traffic safety and transportation efficiency. This paper deals with research efforts relating to radar sensors using millimeter-wave technology, which is fundamental to enabling the all-weather operation of ITS. One of these is for an automotive radar and is used for forward looking and to detect the distance and relative velocity of vehicles ahead. The other is a radar for infrastructure (right-of-way installation) and is used to detect obstructions and vehicles. Both use spread-spectrum (SS) technology, which offers outstanding performance in separation and detection of multiple vehicles. The automotive radar has multiple receiving antennas to determine the direction in which the target lies, using a method whereby the angle is calculated by comparing the power of the signals.