Multi-dimensional constellation tilting for reducing the power loss of tomlinson-harashima precoder

We propose a multi-dimensional extension of the constellation tilting (CT) method for reducing the power loss of Tomlinson-Harashima precoding. By the extension, constellations for multiple signal streams are simultaneously rotated at a proper angle so that the number of available tilting angles is rapidly increased. Then, this growth of the available angles improves the performance of CT and computer simulations show that the proposed extension obtains the enhanced power reduction effect.