A method in a radio base station for transmitting a data signal to a user equipment in a radio communications network, wherein the radio base station is connected to an active antenna array of a number of active transmitting antennas and the radio base station serves the user equipment in the radio communications network, and each active transmitting antenna comprises sub elements, which method comprises: - precoding the data signal with a precoder from a precoder codebook, which precoder codebook comprises precoders for transmitting precoded data signals over a number of transmission antenna ports; - transforming the precoded data signal into a transformed data signal using a transformation; and - transmitting the transformed data signal over at least one of the sub elements of each active transmitting antenna to the user equipment, wherein - precoding with the precoder from the precoder codebook, further comprises precoding the data signal with the precoder for transmitting the precoded data signals in a diversified manner in an azimuth domain, wherein the precoder codebook further comprises a factorized precoder structure for eight transmission antenna ports, and wherein factors in the factorized precoder structure are decomposed into one factor having an effect of performing a beamforming, based on a Discrete Fourier Transform process, over two groups of sub elements of the active transmitting antenna, and into another factor having an effect of altering a relative phase of transmissions between the two groups of sub elements, and - transforming the precoded data signals comprises transforming the precoded data signals using the transformation based on feedback from the user equipment, wherein the transforming further comprises multiplying the precoded data signals from the eight transmission antenna ports with a matrix of beamforming vectors to form a mapping of the precoded data signals from the eight transmission antenna ports to the sub elements of each active transmitting antenna, wherein by way of said transforming, the transmitted data signal is enabled to be directed vertically, and the transformed data signal is limited to be transmitted in a direction within a range of elevation angles, and wherein a threshold level of the range of elevation angles is dependent on a system load. - precoding the data signal with a precoder from a precoder codebook, which precoder codebook comprises precoders for transmitting precoded data signals over a number of transmission antenna ports; - transforming the precoded data signal into a transformed data signal using a transformation; and - transmitting the transformed data signal over at least one of the sub elements of each active transmitting antenna to the user equipment, wherein - precoding with the precoder from the precoder codebook, further comprises precoding the data signal with the precoder for transmitting the precoded data signals in a diversified manner in an azimuth domain, wherein the precoder codebook further comprises a factorized precoder structure for eight transmission antenna ports, and wherein factors in the factorized precoder structure are decomposed into one factor having an effect of performing a beamforming, based on a Discrete Fourier Transform process, over two groups of sub elements of the active transmitting antenna, and into another factor having an effect of altering a relative phase of transmissions between the two groups of sub elements, and - transforming the precoded data signals comprises transforming the precoded data signals using the transformation based on feedback from the user equipment, wherein the transforming further comprises multiplying the precoded data signals from the eight transmission antenna ports with a matrix of beamforming vectors to form a mapping of the precoded data signals from the eight transmission antenna ports to the sub elements of each active transmitting antenna, wherein by way of said transforming, the transmitted data signal is enabled to be directed vertically, and the transformed data signal is limited to be transmitted in a direction within a range of elevation angles, and wherein a threshold level of the range of elevation angles is dependent on a system load.