Patent ID: 6266018
Filing Date: 2001-07-24
Classification: H01Q

Abstract:
A mobile radio apparatus comprising a radio transceiver circuit, a housing accommodating the radio transceiver circuit, and an antenna assembly electrically connected to the radio transceiver circuit and mounted to said housing to be retractable in said housing into a retracted position and extendable out of said housing into an extended position, said antenna assembly comprising a first antenna portion, a second antenna portion and an insulator joint member joining said first antenna portion with said second antenna portion into a linear form to extend in one direction, wherein:said first antenna portion comprises a helical antenna element having one end as a helical terminal, an insulator antenna top enclosing said helical antenna element, and a conductive sleeve connected to said helical terminal of said helical antenna element and having an exposed portion extending outward from said antenna top to an extending end in said one direction;said second antenna portion comprises a whip antenna element having a whip end portion fixed with said joint member and having an opposite whip end, and a conductor stopper fixed to said opposite whip end;said joint member is made of insulator material formed into a rod shape having first and second joint end portions opposite to each other, said first joint end portion being fixed to said whip end portion of said whip antenna element, and said second joint end portion being fixedly fitted in said exposed portion of said conductive sleeve, so that said joint member has an intermediate portion having a length selected from a range of 4 to 7 mm left between said whip end portion of said whip antenna element and said extending end of said conductive sleeve;said conductive sleeve acts as a feed to said first antenna portion from said transceiver circuit when said antenna assembly is in the retracted position, and said stopper acts as a feed to said second antenna portion from said transceiver circuit when said antenna assembly is an extended position; andsaid joint member comprises a tapered peripheral surface at a range between said conductive sleeve and said whip antenna element, said tapered peripheral surface having a diameter at one end of said conductive sleeve larger than that at one end of said whip antenna element.