METHOD AND ARRANGEMENT FOR ADAPTING A MULTI-ANTENNA TRANSMISSION

摘要

A method in a first node for adapting a multi-antenna transmission to a second node over a wireless channel is provided. The wireless channel has at least three inputs and at least one output. The first node and the second node are comprised in a wireless communication system. The method comprising the steps of: Obtaining (401) at least one symbol stream; Determining (403) a precoding matrix having a product structure created by a block diagonal matrix being multiplied from the left with a block diagonalizing unitary matrix; Precoding (404) the at least one symbol stream with the determined precoding matrix; And Transmitting (405) the precoded at least one symbol stream over a wireless channel to the second node.