Abstract: The present invention relates to a method including signalling by a receive node at least one first transmission rank r to a transmit node, where 1?r?R, wherein R is a maximum available rank for a transmission, and at least one predefined precoding matrix corresponds to said first transmission rank r, determining by said transmit node a second transmission rank r? for transmitting data from said transmit node to said receive node, where 1?r??R, defining at least two subsets of precoding matrices for at least one of said at least one first transmission rank r, selecting one of said at least two subsets of precoding matrices in accordance with a channel quality estimate for a radio channel, and signalling said selected one subset of precoding matrices, wherein said selected one subset of precoding matrices is associated with said at least one predefined precoding matrix.

Abstract: The invention concerns a method for precoding in an open loop transmission communications system, wherein the method includes precoding data at each of M REs with a precoding matrix, precoding each of DM-RSs with one column of a precoding matrix which is same as that used for precoding M data REs. The method is distinguished by using at least L?2 different precoding matrices from a set of precoding matrices W to precode the M REs and the E allocated REs such that REs precoded with a first precoding matrix are interleaved with REs precoded with at least one additional, different precoding matrix and the number of used precoding matrices L is adapted to the transmission rank r and number N of available DM-RS. The invention further concerns a radio transmitter and a user equipment.