| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To enable a miniaturized vehicle-mounted millimeter-wave radar antenna to have desired low sidelobe characteristics. <P>SOLUTION: The transmission (or reception) side is sturctured of unit antennas (TX1, TX2), having two-element multiple horns, while the receiving (transmimitting) side is structured of units antennas (RX1, RX2) having four-element multiple horns. Each element of the two-element unit antennas has an aperture, having a width W0 in the elevation angle direction. As for the four-element unit antennas, the outer two elements in the elevation direction have apertures, each having an identical width W1 in the elevation angle direction; while the inner two elements in the elevation direction have apertures, with each having identical width W2 (> W1) in the elevation angle direction. The aperture face of each element is disposed on the elevation direction. Each element is connected to a waveguide, having a branch section for coupling electromagnetic waves at a supply point. With a multiple horn structure of the two elements, the antenna height in the elevation direction is decreased, and desired main directivity characteristics are obtained by the combination of transmission/reception of the radiation characteristics with the four-element multihorn. The directivity characteristics are set by the size and disposition in the elevation direction of each element of the two and four elements. <P>COPYRIGHT: (C)2004,JPO</p> |
