Sarantel Limited

David Michael Wither

Oliver Paul Leisten

Andrew Robert Christie

Sinikka Lyyra

Frank Kwasi Frimpong

Martyn Leslie Tongue

A backfire dielectrically loaded antenna for operation at a frequency in excess of 200 MHz includes a dielectric core having a relative dielectric constant greater than 5 and having an outer surface defining an interior volume the major part of which is occupied by solid material of the core; a three-dimensional antenna element structure including at least one pair of elongate conductive antenna elements disposed on or adjacent the side surface portion of the core and extending from a distal core surface portion towards a proximal core surface portion; a feed structure having an axially extending elongate laminate board including a transmission line section acting as a feed line which extends through a passage in the core from the distal core surface portion to the proximal core surface portion, and an antenna connection section having an integrally formed proximal extension of the transmission line section the width of which, in the plane of the laminate board, is greater than the width of the passage; and an impedance matching section coupling the antenna elements to the feed line.

Dielectrically loaded antenna and radio communication apparatus

A radio communication apparatus including: (a) a backfire dielectrically loaded antenna for operation at a frequency in excess of 200 MHz comprising: an electrically insulative dielectric core of a solid material having a relative dielectric constant greater than 5 and having an outer surface including oppositely directed distal and proximal surface portions extending transversely of an axis of the antenna and a side surface portion extending between the transversely extending surface portions, the core outer surface defining an interior volume the major part of which is occupied by the solid material of the core; a three-dimensional antenna element structure including at least one pair of elongate conductive antenna elements disposed on or adjacent the side surface portion of the core and extending from the distal core surface portion towards the proximal core surface portion; a feed structure in the form of an axially extending elongate laminate board comprising at least a transmission line section acting as a feed line which extends through a passage in the core from the distal core surface portion to the proximal core surface portion, the antenna having exposed contact areas on or adjacent the core proximal surface portion; and (b) radio communication circuit means having an equipment laminate circuit board with at least one conductive layer, the conductive layer or layers having a plurality of contact terminal support areas to each of which is conductively bonded a respective spring contact positioned so as to bear resiliently against respective ones of the exposed contact areas of the antenna.

A dielectrically loaded backfire helical antenna has a cylindrical ceramic core and a feed structure which passes axially through the core to a distal end face of the core where it is connected to helical conductors located on the outside of the core. Opening out on the proximal end face of the core is a cavity which is coaxial with the feed structure. A conductive balun layer encircling a portion of the core extends over the proximal end face of the core and the wall of the cavity to connect the helical elements to the feeder structure when it emerges into the cavity. The presence of the cavity and accommodating some of the length of the balun in the cavity allows a reduction in the size and weight of a dielectrically loaded backfire antenna.

A-dielectrically-loaded antenna

Dielectrically-loaded antenna

A unitary feed structure for sliding installation in a passage in the insulative core of a dielectrically-loaded antenna comprises the unitary combination of a tubular outer shield conductor and elongate inner conductor which extends through the shield conductor and is insulated from the latter. The shield conductor and inner conductor have oppositely directed radially extending connection members at an end of the feed structure, these connection members being integrally formed as part of the respective conductors so that the feed structure can be inserted as a unit into the passage in the antenna core so that the connection members engage respective connection portions formed on an end face of the core adjacent on end of the passage. Soldering of the connection members to the connection portions can be performed as a single operation so as to connect the feed structure to conductive antenna elements plated on the outer surface of the core.

Growing community of inventors

Northampton, United Kingdom

David Michael Wither