ANTENNA

摘要

An antenna of generally symmetrical form and having a longitudinal axis comprising: a feed point member located at one end of the antenna; an attachment point means at the other end of the antenna to the one end and spaced axially from the one end; an insulator member extending the axial length of the antenna between the feed point member and the attachment point means; a duct extending through the insulator member from the one end to the other end to the end; and a reactive element of electrical conducting material extending through the duct to define an electrically conducting path linking the feed point member to the attachment point means. Preferably the attachment point means provides for the attachment of antenna, or at least the reactive element or an extension thereof, to an external component such as a circuit board to provide a ground plane for the antenna. The antenna can include a reactive element providing for the conducting path length to be longer than a direct distance along the duct between the feed point member and the attachment point means. To this end the reactive element at least in part follows a meandering path along the duct between the feed point member and the attachment point means.