2020 Volume 11 Issue 4 Pages 546-560
The multiple-input multiple-output (MIMO) system is one of the wireless communication methods that use multiple transmit and receive antennas. To ensure security on the physical layer and also to enhance channel coding efficiency, a chaos MIMO (C-MIMO) system was previously proposed. In this system, a chaotic dynamical system is used for modulation. In this paper, we revealed that the original C-MIMO system does not effectively use the information of bits that are used for modulation, which results in a difficulty in distinguishing encrypted symbols. To solve this issue, we propose a new modulation method for the C-MIMO system. We evaluated the performance of the proposed C-MIMO system and showed that the proposed C-MIMO system significantly improves block error rates.