“…matrix P̂s is not diagonal in the presence of coherent sources. Table 1 shows the complexity in terms of number of FLOPs for major processing steps of the proposed method, universal 2D DOA estimation [10], and joint elevation and azimuth angle estimation [19]. It can be inferred from the table that the proposed method has much lower computational complexity compared to other methods, where N, L, and K denote the number of antenna elements, snapshots of the received signals, and number of sources, respectively.…”