Central Glass Company, Limited

Nissan Motor Company Limited

Asahi Glass Company, Limited

Clarion Co

Masahiro Ohnishi

Yoji Nagayama

Shingo Tadokoro

Osamu Ueda

Masaru Shiina

A glass antenna device for an automobile including a rear window glass sheet; an electric heating type defogger formed on the glass sheet, which is provided with heater strips and positive and negative bus bars for feeding a current to the heater strips; and a noise filter including at least a coil, which is connected between the positive bus bar and a positive terminal of a d.c. power source for the defogger. The negative bus bar is grounded to the automobile body, and antenna conductors are provided in a region in the rear window glass sheet other than the region where the defogger is formed. An antenna conductor element of the antenna conductors extends substantially parallel to the heater strips of the defogger, is more than half in length than a width of the rear window glass sheet, and is located in the range of 15 mm-50 mm apart from an end heating strip of the heating strips of the defogger nearest to the antenna conductor element. The coil has an inductance value in the range of 0.5-10 .mu.H.

Glass antenna device for an automobile

A second antenna is provided to a vehicle rear window glass in order to prevent a fall or dip of the gain of the antenna system in a particular direction or directions, thereby improving the directivity characteristic and increasing the gain. The second antenna consists of a feed point and a pair of first and second elements connected to the feed point. The first element has, in an area of the space above a first antenna or in a space defined between the upper and lower ends of a first antenna, at least one horizontal conductive strip. In one embodiment, in which the feed point is arranged in a marginal area of the space under the defogging heater element, the first element further has a vertical conductive strip arranged in an area of the space between the heater element and a lateral edge of the window glass. The second element is arranged in an area of the space under the defogging heater element and made up of a conductive strip assembly of various shapes such as -shape, a rectangular loop or loops, or a T-shape. The second element is connected to a bus bar or a heating strip of the defogging heater element in order to further increase the gain of the antenna system in all directions.

Automotive window glass antenna

Growing community of inventors

Isehara, Japan

Masahiro Ohnishi