Modern automobiles require antenna systems for causing built-in receivers to positively receive various TV and radio broadcast waves or communication waves for car-telephones. Such antenna systems also are very important for citizen-ban communications between automobiles and other movable or ground stations.
The present invention relates to an automobile antenna and more particularly to an improved antenna system which can efficiently detect surface currents induced on the body of an automobile by received broadcast waves with detected signals being supplied to various built-in receivers mounted within the vehicle body.
To achieve this aim, the present invention provides an automobile antenna system composed of two antennas attached to the rear windshield of a vehicle body, a high-frequency pickup provided on the front pillar of the vehicle body for detecting the lowering of the output level of the main antenna in advance, and an antenna selecting signal generator which actuates a switch circuit so that the main antenna, the output level of which is predicted to dip after a predetermined lapse of time, is changed over to the sub antenna, in which no dipping is occurring, whereby the output level of the diversity-reception antenna is maintained at a predetermined value or higher even when the vehicle drives into an area where stationary waves are being produced.
Global Automobile Antenna Industry 2016 Market Research Report was a professional and depth research report on Global Automobile Antenna industry that you would know the world's major regional market conditions of Automobile Antenna industry, the main region including North American, Europe and Asia etc, and the main country including United States ,Germany ,Japan and China etc.