Abstract:
Here, operation for 3D beam forming is disclosed. UE, receiving reference signals from one or more base stations (eNBs), may report feedback information comprising precoding matrix information to the one or more eNBs. The precoding matrix information indicates a first type precoding matrix for a horizontal direction and a second type precoding matrix for a vertical direction. eNBs may transmit signals, which are precoded based on a third type precoding matrix for beam forming both on the horizontal direction and the vertical direction.