Daisy Chain MIMO Antenna for Whole Azimuth Tens-of-Gigabit Connected Cars

This paper presents a multiple-input multiple-output (MIMO) antenna system that has the ability to perform beam scanning operation over the whole azimuth, with the aim of realizing vehicular communications at several tens of gigabits capacity. The developed MIMO antenna comprises 64 elements arranged in a dual-ring structure, like daisy chain flowers, named daisy chain MIMO antenna, with 32 subarrays by pairing two elements for each subarray in a rotational way, forming 32 independent subchannels for MIMO transmission, covering all angles toward the target of communication. The analytical results reveal that the proposed antenna system provides a channel capacity of more than 200 bits/s/Hz at the signal-to-noise power ratio (SNR) of 30 dB over the whole azimuth, which is equivalent to 20 Gbps for the bandwidth of 100 MHz.