| abstract |
A broadband internal antenna 40, suitable for use in mobile telecommunications, comprises a number of elongate co-axial coil elements 41, each having a different coil pitch (51, 52 in fig 5) and connected in series. The coil axis is arranged parallel to a number of micro-strip elements 64 (fig 6a 6b also) formed with a base to provide a second antenna element 42 in addition to the coil antenna element 41. The coils 41 and micro-strips 42 couple electromagnetically and are arranged such that their respective current paths are in different directions. The coupling of the coils and micro-strips effects the tuning of the antenna system, and the length of the micro-strips can be varied. The micro-strips are connected to one end of the coils at contact pad 61. The other end of the coil is connected to pad 65 which does not contact the micro-strips. |