Algorithm 1 An algorithm of FL for SS.

$i\leftarrow 0$ $I\leftarrow N$ while$i<I$do     $C^i\leftarrow$ set of clusters (clustering sensors by mean SNR values)     for each $c\in C^i$ do         for each $s\in S_c^i$ do            if $i==0$ then                initialize $w_s^i$            else                $w_s^i\leftarrow W_c^{(i-1)}$            end if            calculate $w_s^i$ to minimize $L_s^i\left(w_s^i\right)$         end for         $W_c^i\leftarrow \frac{1}{N_{S_c^i}}{\sum }_s^{S_c^i}{w}_s^i$     end for     $i\leftarrow i+1$ end while