Algorithm 1 TDOA measurements in 2-D underwater plane

Input: Coordinate $\left(x_i,y_i\right)$ of hydrophone. Output: $\left(x,y\right)$. Steps: 1: Calculation time difference by ${\tau }_i=t_i-t_1$. 2: Substitute ${\tau }_i$ into Equations (15)–(17) to get $A_i,B_i,$ $D_i$. 3: Substitute $A_i,B_i,D_i$ into (14) to get $\left(x,y\right)$. 4: End