Broadband Air-to-Ground communications with adaptive MIMO datalinks

In order to further increase the transmission rate of the broadband Air-to-Ground (A/G) aeronautical communications, the adaptive Multiple-Input and Multiple-Output (MIMO) system is proposed in this paper. Specifically, the MIMO system can increase the capacity of the data link just as it does in the terrestrial mobile communications system. Due to the Line-of-Sight (LOS) property of the Three Dimensional (3D) A/G channel, the adaptive smart antenna array is employed to emulate the uncorrelated MIMO channels. Then, the capacity upper bound can be achieved based on optimization of the inter-element distance between the antennas in the uniform virtual linear array. This structure can be combined with the Non-Continuous Interferometry OFDM (NCI-OFDM) system to form the MIMO-NCI-OFDM system, which is expected to be a promising solution to the broadband A/G communications system.