Mobile communication device with reduced electric field emission levels near the earpiece

Abstract

A mobile communication device (1) is provided with an antenna (10) having an antenna element (10a) and a conductive ground element (26) to cooperate with the antenna element. In use, RF currents are generated in the conductive ground element and as a result an oscillating electric field arises. The conductive ground element is arranged in the device (1) such that the point of highest electric field is located away from the region where the earpiece (5) is positioned in order to reduce the emission of the electric field to the ear (12). The conductive ground element (26) may be provided in a conductive layer of the Printed Circuit/Wire Board (24) of the device. The point of highest electric field in a in a conductive layer arises at the end of the physical path near a physical end of the layer, which in a conventional flip-phone typically corresponds to the top of the first hinged body part (2) where the earpiece (5) is also positioned. According to the invention, the layer is serpentine shaped and arranged such that the end of the electrical path of the Printed Circuit/Wire Board is located approximately half a wavelength of the oscillating field away from the area of the earpiece. Alternatively, tracks or wires (27, 28) acting as ground extensions may be connected to the ground plane (26) to move the end of the electrical path and the high electric field away from the region of the earpiece.

Dependencies are inferred from the claim text.