A method and a communication device adapted for designing a hybrid beamforming (HB) precoding used in a mobile communication system with an antenna array, the method including aggregating spatial channel vectors received by the antenna array; performing a linear factorization of the aggregation; truncating the linear factorization to generate truncated channels; and designing the HB precoding based on the truncated channels, wherein the HB precoding includes a linearly generated analog beamforming component and a linearly generated digital beamforming component.