There is provided mechanisms for processing uplink signals. A method is performed by a RRU (200). The method comprises obtaining uplink signals (S102) as received from wireless devices at antenna elements of an antenna array of the RRU (200), wireless device being associated with its own at least one user layer. The method comprises capturing (S104) energy per user layer by combining the received uplink signals from the antenna array for each user layer into combined signals, resulting in one combined signal per user layer. The combining for each individual user layer is based on channel coefficients of the wireless device associated with said each individual user layer. The method comprises providing (S106) the combined signals to a BBU (300).