The invention relates to generating compressed channel state information and restoring the channel state information from the compressed channel state information. A computation device for compressing channel state information, CSI, representing a channel transfer function H having a spatial dimension and a frequency dimension comprises a transforming unit configured to perform a spatial transformation and a frequency-to-time transformation subsequently and in any order on the channel transfer function H to obtain a transformed channel transfer function HT, and a compressing unit configured to select values of the transformed channel transfer function HT and to generate compressed channel state information, CCSI, based on the selected values.