Multiband antenna system for use in motor vehicles

摘要

A multiband antenna system for use in a motor vehicle comprising an antenna unit responsible for first and second frequency bands. The antenna unit is electrically coupled to a first conduit tube which is in turn coupled coaxially to a second conduit tube with a capacitor being interposed therebetween. The capacitor is arranged so as to act as a short with respect to the first frequency signal and act as an open for the second frequency signal. The first conduit tube is connected to a first feeding terminal for deriving the second frequency signal and the second conduit tube is coupled to a second feeding terminal to derive the first frequency signal. This antenna system is constructed by using only one antenna unit having a predetermined length, thereby allowing simplification of the arrangement of the antenna system for easy manufacturing.