Use of AMC materials in relation to antennas of a portable communication device

The antenna arrangement according to 1, where said island is designed to have a high surface impedance only for the frequency range of the antenna surrounded by the island.

An antenna arrangement for provision in a portable communication device, the antenna arrangement comprising:

• a plurality of antennas, all antennas of the plurality of antennas provided above a common grounding layer and in groups according to operational frequency ranges of the plurality of antennas, where each group covers a separate frequency range,
• where the common grounding layer comprises an Artificial Magnetic Conductor (AMC) material structure facing the plurality of antennas, the AMC material structure being divided into sections, where each AMC material structure section faces the group of antennas and is designed to have a high surface impedance for the frequency range of the group of antennas, and
• where at least one section of the AMC material structure further comprises at least one island occupying an area that is aligned with and surrounds an antenna in a corresponding group, said island being designed to have a high surface impedance for the frequency range of the corresponding group and being surrounded by AMC material having a high surface impedance for the frequency range of another group.

A portable communication device comprising:

• a plurality of antennas provided above a common ground layer and in groups according to operational frequency range of the antenna, where each group covers a separate frequency range,
• where the common grounding layer comprises an Artificial Magnetic Conductor (AMC) material structure facing the antennas, the AMC material structure being divided into sections, where each AMC material structure section faces the group of antennas and is designed to have a high surface impedance for the frequency range of the group of antennas, and
• where at least one section of the AMC material structure further comprises at least one island occupying an area that is aligned with and surrounds an antenna in a corresponding group, said island being designed to have a high surface impedance for the frequency range of the corresponding group and being surrounded by AMC material having a high surface impedance for the frequency range of another group.