METHOD AND APPARATUS FOR OPEN LOOP TRANSMISSION IN A MULTIPLE ANTENNA WIRELESS COMMUNICATION SYSTEM

摘要

The invention concerns a method for precoding in an open loop transmission communications system, wherein the method comprises: - precoding data at each of M RE:s 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 RE:s. The method is distinguished by: - using at least L = 2 different precoding matrices from a set of precoding matrices W to precode the M RE:s and the E allocated RE:s such that RE:s precoded with a first precoding matrix are interleaved with RE:s 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 comprises a radio transmitter and a user equipment.