Dual-Circular 8 ⨯ 8 MIMO Array with Synchronized Beam Scan for Over-Gbps Inter-Vehicle Communications

Abstract

This paper presents an 8 ⨯ 8 multiple-input multiple-output (MIMO)antenna that utilizes a circular phased array technology, with the aim of realizing over-Gbps inter-vehicle communications. The 8 ⨯ 8 MIMO array comprises two circular phased array 4 ⨯ 4 MIMO antennas. In the antenna system, the desired directivity of eight subarrays is varied by the electromagnetic mutual coupling. Therefore, the interval $D$ between the centers of the circles is designed to increase the channel capacity. The results show that when $D$ is greater than 28 cm, a high level of the channel capacity over 70 bits/ s/Hz is realized with a small variation in the channel capacity depending on the direction of the incoming wave owing to a large gain of all subarrays in the communication direction. Consequently, when the bandwidth is 100MHz, 7 Gbps high-speed inter-vehicle communications can be achieved using the proposed antenna.