Two-Dimensional Circle Antenna Layout for Aeronautical MIMO Communications

Aeronautical multiple-input-multiple-output (MIMO) communications cannot utilize the multipath to build up the decorrelated channels due to the obvious line-of-sight (LOS) transmission. Then, the elaborate design of antenna layout is expected to decrease the correlation among the MIMO channels. However, the existing one-dimensional layouts like uniform linear array (ULA) and nonuniform linear array (NULA) have the weakness that the different flight azimuth may reduce MIMO capacity, i.e., in some specific azimuth angle, the capacity even degrades and approaches to the single antenna. In this letter, a two-dimensional circle antenna layout is proposed and optimized to eliminate such a negative effect and to maintain a better capacity performance of the aeronautical MIMO transmission.