| 摘要 |
A vehicle window antenna comprises a grid of conductive frit material affixed to the inner side of a window glass in a confined area above a window heating element comprising a grid of similar material similarly affixed and covering most of the window viewing area. The window glass is retained in a channel surrounding an aperture edge of the vehicle body by a mounting and sealing member comprising a strip of a urethane material which is electrically conductive with a low impedance at radio frequencies. At least one electrically conducting ground element, made of the same frit material, is affixed to the inner side of the window glass and electrically coupled at radio frequencies through the mounting and sealing member to the vehicle body. The ground element is provided at the point where the antenna element most closely approaches the mounting and sealing member and aperture edge and has an inner edge extending sufficiently close to the antenna element, as compared with the mounting and sealing element, to replace the latter in defining the closest distance between the ground plane and the antenna element and thus provides a predetermined antenna impedance or other antenna parameter regardless of variations in position, configuration and dimension of the mounting and sealing element. The ground element may be located at one of the upper corners of the antenna element and may comprise a generally L shaped element between the antenna element and the upper corner with a horizontal portion and a vertical portion, the latter extending along the side of the antenna element. The antenna may also comprise a similar ground element adjacent the other upper corner of the antenna element.
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