Algorithm 1 Balance Algorithm.

Input: Initial deployed information of nodes and UAVs

Output:$N_p$, $N_{node}$

1: $N_p$ = $N_{node}$ = 0, k = 1, $T_{now}$ = 0;

2: Step 1. Synchronization;

3: UAV sends k-th ’Beacon’ message;

4: Network update, obtain the ${\mathbb{S}}_{k_B}^1$ and ${\mathbb{S}}_{k_B}^2$;

5: Step 2. Data Communication;

6: while $T_{now}<T$ do

7:        Let ${\mathbb{S}}_{kB}^{1,2}\triangleq {\mathbb{S}}_{kB}^1\cap {\mathbb{S}}_{kB}^2$, ${\mathbb{S}}_{kB}^{1,o}\triangleq {\mathbb{S}}_{kB}^1-{\mathbb{S}}_{kB}^{1,2}$, and ${\mathbb{S}}_{kB}^{2,o}\triangleq {\mathbb{S}}_{kB}^2-{\mathbb{S}}_{kB}^{1,2}$;

8:        if ${\mathbb{S}}_{kB}^{1,2}$ = ⌀ then

9:                Apply PCdFS mechanism (Algorithm 2) to balance the communication between ${\mathbb{S}}_{kB}^{1,o}$ and $UA{V}_1$, ${\mathbb{S}}_{kB}^{2,o}$ and $UA{V}_2$ respectively;

10:        else

11:                Apply PMCdFS algorithm (Algorithm 3) for the balancing between mobile nodes in ${\mathbb{S}}_{kB}^{1,2}$ and multi-UAVs, and obtain ${\mathbb{S}}_{k_B}^1$ and ${\mathbb{S}}_{k_B}^2$ through PMCdFS algorithm;

12:                Apply PCdFS mechanism (Algorithm 2) to balance the communication between ${\mathbb{S}}_{kB}^{1,o}$ and $UA{V}_1$, ${\mathbb{S}}_{kB}^{2,o}$ and $UA{V}_2$ respectively;

13:        end if

14:        Update $T_{now}$, k, $N_p$ and $N_{node}$;

15: end while

16: return $N_p$ and $N_{node}$;