Abstract: An antenna (400; 600) for transmitting and receiving radio-frequency signals comprises a cylindrical coil conductor (601) having a turn A and a turn B and between them other turns. The pitch (x1) of turn A is unequal to the pitch (x2) of said turn B, and the pitches of the other turns between turns A and B are in the order of magnitude between the pitches of turns A and B.

Abstract: A radio device comprises an antenna for transmitting and receiving radio frequency signals. The antenna comprises a radiating antenna element (201, 602, 701) and a dielectric protective casing (202, 703) attached to each other, whereby the dielectric protective casing substantially encloses the antenna element. Further the radio device comprises a protective casing (205) of the radio device for mechanically supporting the radio device and for protecting its electrical components, and a printed circuit board (203) within the protective casing for connecting the electrical components to the radio device and for forming the electrical connections between the components. The antenna is mechanically fastened to the radio device with the aid of counterpart fastening shapes (301, 302, 303, 304, 305, 306, 307, 308) located in the antenna's protective casing and in the radio device's protective casing.

Abstract: The present invention relates to a coupling element (21) by which the coupling of a resonator (24) is adjusted in a radio frequency filter. The coupling element of the invention is a strip made of flexible conductor material being shaped symmetrical relative to the normal, that is, the symmetry axis of the longitudinal axis extending via the centrepoint of the strip in the longitudinal direction. The strip (21) is fixed at least at two points of an edge in the longitudinal direction to the circuit board (25) either by surface mounting on pads (33, 35, 36) or by soldering into holes borred in the circuit board to be at appropriate space from the resonator coil (34) and from the surface of the circuit board (25). One (33) of the fixing points is grounded and another (36) is connected to the signal conductor in the filter. The coupling can easily be adjusted by bending the board relative to the symmetry axis either one-sidedly or on both sides.

Abstract: A filter construction known in the art comprises at least a number of helix resonators (1) and an insulation material plate, the projections (2a) projecting from the rectangular lower part (2) whereof are provided inside the helix resonators and thus supporting them. The filter housing (6), defined by a cover (8) and the side walls, is provided with compartments, so that each compartment includes a helical resonator. As taught by the invention, at least two guides (71) projecting from the surface are extruded in the same phase as the compartment on the inner surface of the cover, wherebetween the tip part of the projection (2a) supporting the resonator enters when the filter is assembled. The guide can be a hemisphere or a rib-like bulge.

Abstract: A high-frequency filter employing helix resonators and a metallic or metallized cover. The cover contains at least two helix-shaped resonator coils separated from each other by a metallic or metallized partition provided with an aperture which there is a tuning strip, by reducing the size of which the size of the aperture can be enlarged and thereby the electrical coupling between the resonators adjusted.