FEEDBACK CHANNEL TRANSMISSION AND DETECTION IN MULTI ANTENNA WIRELESS COMMUNICATION SYSTEMS

摘要

A method by a network node in a communications system includes determining a codebook subset restriction indicating a reduced set of precoding matrices out of an original set of precoding matrices in an original codebook (601). The full set of Precoding Matrix Indicator, PMI, bits is used to identify the original set of precoding matrices in the original codebook. The method includes determining a reduced set of Precoding Matrix Indicator, PMI, bits for use in a feedback channel based on a number of entries in the reduced set of precoding matrices (603). The reduced set of PMI bits has fewer bits than the full set of PMI bits. Related user equipments, methods by user equipments and network nodes are disclosed.