Transmitting/receiving method for multi-user multiple-input multiple-output system

A transmitting method for a Multi-User Multiple-Input Multiple-Output (MU-MIMO) system, the transmitting method comprising:

• performing QR decomposition on a Hermitian transpose matrix of a channel matrix to obtain a first matrix and a second matrix as a triangular matrix;
• obtaining a preprocessing matrix by using the first matrix;
• forming an effective channel based on the preprocessing matrix by a block triangulation technique,
• wherein column vectors of the first matrix are orthogonal basis vectors;
• and
• wherein the preprocessing matrix is a product of the first matrix and a complex rotation matrix.