Cascade AOA Estimation Technique Based on The Combined Flexible Massive Array Antenna

In the next-generation communication system, various communication services employs beamforming and massive array antenna techniques for reliable and efficient wireless communications. Based on the massive array antenna with a huge number of elements, the beamforming technique such as the estimation of Angle of Arrival (AOA) may not operate in real time, because the computational complexity for this situation should be extremely high. In order to enhance this problem, in this paper, we propose the cascade AOA estimation algorithm based on the Flexible Massive Combined Array (FMCA) antenna. The proposed algorithm finds AOA groups including multiple signal AOAs employing Capon based on some elements of the FMCA antenna, and it estimates the detail signal AOAs in the found AOA groups employing Beamspace Multiple Signal Classification (MUSIC) based on entire elements of the FMCA antenna. In addition, we provide the received signal model for applying the FMCA antenna and the proposed cascade AOA estimation algorithm.