Improved Polarized 2x2 MIMO Spatial Multiplexing Method for DVB-NGH System

Recently terrestrial digital broadcasting systems have experienced a growth with the demand of high-data rate. In order to meet such demand, the multiple-input multiple-output (MIMO) technology has received wide attention. This paper proposes a pre-coding method, which provides high-space channel correlation for the improved performance over terrestrial broadcasting channels when the MIMO spatial multiplexing (SM) is adopted for digital video broadcasting-next generation handheld systems. When signals with two different modulation orders are transmitted through two antennas, a method that is based on non-uniform power is also proposed for improved reception performance. To optimize the proposed method, phase shifting values for the pre-coding method and appropriate non-uniform power ratio are obtained. These obtained parameters are applied to a terrestrial broadcasting system, and then the performance improvement over the conventional SM is shown through computer simulations.