Algorithm 2 Post processing procedure for finding the final active BSs.

Initialization: let ${\mathcal{A}}^{\left[0\right]}=\{1,\cdots ,\widehat{A}\}$, the network power consumption $P_{\mathrm{total}}^{{\mathcal{A}}^{\left[0\right]}}$ and the iteration index  $i=0$.  Step 1: Update the iteration number $i=i+1$.  Step 2: Let ${\mathcal{A}}^{\left[i\right]}={\mathcal{A}}^{[i-1]}\setminus \left\{{\pi }_i\right\}$, and solve problem ${\mathbf{P}}_5$.  Step 3: If problem ${\mathbf{P}}_5$ is infeasible, go to Step 5; Otherwise, go to Step 4.  Step 4: If $P_{\mathrm{total}}^{{\mathcal{A}}^{\left[i\right]}}\le P_{\mathrm{total}}^{{\mathcal{A}}^{[i-1]}}$, go to Step 1; Otherwise, go to Step 5.  Step 5: Obtain the final active BS set ${\mathcal{A}}^{★}={\mathcal{A}}^{[i-1]}$.  Step 6: Solve problem ${\mathbf{P}}_6$ and obtain the final network power consumption $P_{\mathrm{total}}^{{\mathcal{A}}^{★}}$, beamforming and  AN (i.e., $\{{\mathbf{W}}_k^{★},{\mathbf{V}}^{★}\}$).