Patent ID: 8885752

Claim:
A user equipment (UE) for communication in a multiple-input multiple-output (MIMO) network, the UE comprising: a channel estimator to estimate channel information based on downlink reference signals received from an evolved Node B (eNodeB); a vector quantizer to quantize a first portion of the channel information using a codebook; a scalar quantizer to quantize a second portion of the channel information based on a vertical angle of a radio frequency (RF) beam transmitted by the eNodeB; and a pre-coding matrix indicator (PMI) module to calculate a PMI vector based on the estimated channel information, the PMI vector comprising coefficients of linear transmit antenna weights for steering the RF beam at the eNodeB in a horizontal direction, and wherein one or more of the coefficients of the PMI vector are multiplied by a vertical phase shift parameter based on steering the RF beam at the eNodeB in to the vertical angle; wherein the vertical phase shift parameter is of the form: ⅇ j ⁢ 2 ⁢ ⁢ π λ ⁢ d v ⁢ cos ⁢ ⁢ θ 0 , where λ is a wavelength of the downlink reference signals, d V is a vertical distance between antennas in a two-dimensional (2D) antenna array at the eNodeB, and θ 0 is the vertical angle.