A New MIMO Scheme for Saving Power Consumption

In this letter, we introduce a novel transmission scheme to a multi-input multi-output (MIMO) system employing an
${M} \times {M}$
antenna structure. The conventional MIMO loads parallel signals onto all transmit antennas to realize essentially M separate channels to achieve high channel capacity. In contrast, the proposed method can dynamically activate a subset of the transmit antennas at each transmission while maintaining the same channel capacity as conventional MIMO. The dynamic activation of the transmit antennas offers a statistically similar advantage to spatial modulation, leading to a reduced number of active RF chains and power saving as well. The theoretical analysis is conducted through the proposed transformation matrix that operates from the signal source to the transmit signal. The effectiveness of this approach is investigated regarding capacity issues and antenna utilization, which are confirmed by simulation results.