Abstract: The object of the present invention is to achieve an antenna for both receiving and transmitting circularly polarized RF signals which is smaller and lighter than prior art antennas as well as to achieve one antenna for both receiving and transmitting circularly polarized RF signals which has better characteristics for a given physical length than prior art antennas. This is achieved by providing an N-helical-filar antenna with N radiating elements coaxially arranged and defining a cylindrical envelope where each individual radiating element is capacitively coupled to another radiating element.

Abstract: The present invention relates to problems with how to achieve a reliable and efficient connection between circuitry in a radio communication device and an extendable and retractable antenna device, which is operable in both extended and retracted position as well as during extension and retraction. This problem is solved by providing an antenna device with radiating means, movable between an extended and a retracted position. The antenna device having a feeding arrangement comprising at least a first connection member (306, 307, 308; 801, 802, 803) electrically coupled to and movable with the radiating means. The feeding arrangement further comprises at least a second connection member (309, 310; 903, 904, 905, 906, 907; 1003, 1004, 1005) arranged for being electrically coupled to the first circuitry and fixedly mounted on a support unit. Moreover, the first connection member being electrically coupled to the second connection member in all positions between and including the extended and retracted positions.

Abstract: The object of the present invention is to achieve an easily mounted antenna device for receiving and/or transmitting circular polarized RF signals in at least one and preferably two frequency bands with a well defined interface towards the circuitry in the hand-held mobile communication device. This is obtained by providing N radiating elements where N is an integer greater than one, a support means arranged to support said radiating elements, a housing, and at least one connection member arranged to be easily connectable to a circuitry on a first printed circuit carrier arranged in said hand-held mobile communication device. Further more, providing at least one phasing network comprising N first ports arranged to be connected to said radiating elements and at least one second port arranged to be connected to said connection member, said phasing network being mounted to said support.

Abstract: An antenna system including an antenna device and feed device for transmitting and receiving circularly polarized RF waves in a first mode of operation, and of linearly polarized RF waves in a second mode of operation, and a hand-held mobile communication device provided with such an antenna system. A radiating structure (10) including N helical radiating elements (12A-D), being coextending and coaxially arranged on a support structure (11) are fed in order to provide for transmission/reception of circularly polarized RF waves in the first mode of operation. N is an integer greater than one. Further, means (24A-D, 16, 17, 19, 25, 25A) are arranged for essentially uniform excitation of the helical radiating elements (12A-D) in order to provide for transmission/reception of linearly polarized RF waves in the second mode of operation.