Patent ID: 9154205
Filing Date: 2015-10-06
Classification: H04B,H04L,H04W

Abstract:
1. A method of performing downlink beamforming in a wireless access system, comprising the steps of: transmitting, by a base station, a reference signal to a user equipment via a first antenna set; receiving, by the base station, channel state information (CSI) on the first antenna set from the user equipment; and transmitting, by the base station, a downlink channel to the user equipment in a manner of beamforming the downlink channel using a precoding matrix for the first antenna set and a second antenna set, wherein CSI on the second antenna set, which has not transmitted the reference signal, is calculated using the CSI on the first antenna set, and wherein the CSI on the second antenna set is calculated in a manner of applying an interpolation scheme or an MMSE (Minimum Mean Square Estimation) scheme to the CSI on the first antenna set.