Patent ID: 8432329

Claim:
An antenna arrangement for a wireless communication system arranged to have at least one transmit mode and at least one receive mode, the arrangement comprising at least three directional antennas in an antenna configuration, each directional antenna being arranged to have an azimuthal radiation pattern shaped as a beam, each beam covering an angular sector, such that a combined radiation pattern of all beams in a first transmit mode is arranged to provide a full 360° omnidirectional coverage, said directional antennas being spatially arranged such that the beams covering neighbouring angular sectors partially overlap and such that the radiation patterns of all beams are arranged to be combined by connecting the directional antennas to the same transmitting line characterized in that: at least two directional antennas covering neighbouring angular sectors and with their phase centres within a circle with a radius below two λ are arranged in a first cluster in which all directional antennas have substantially the same polarization, where λ is a mean wavelength in the receive/transmit frequency band, the antenna arrangement comprises at least one cluster, the polarization of the separate directional antenna or the antenna cluster is substantially orthogonal to the polarization of the separate directional antenna or antenna cluster covering a neighbouring angular sector, the sum of antenna clusters and, separate directional antennas not included in a cluster, is an even number, a directional antenna is part of one cluster only, in the same antenna configuration thus creating an omnidirectional azimuthal radiation pattern substantially without null-depths.