Algorithm 1. The CP Determination for Tracking a Single Target

Initialization: Get information of the WSN topology, including the node positions, LOSL formulas  Step 1: get the first CP as the middle point of the edge LOSL $L\left(1\right)$, and decide $R\left(1\right)$.  Step 2: Once $L\left(i\right), i>1$ is triggered   Select the highest probability segment $S\left(i\right)$ on $L\left(i\right)$, which is nearest to $R\left(i-1\right)$.   Estimate CP as the middle point of $S\left(i\right)$ and decide that $R\left(i\right)$ is the opposite region of $S\left(i\right)$.  Step 3: Go back to Step 2, until the target walks out of the monitoring area.