Trilateration Method for Calculating Unknown Node Coordinates

This program implements the log-normal shadowing model for RSSI-based distance measurement. The model utilizes the Received Signal Strength Indicator (RSSI) between reference nodes and target nodes to estimate inter-node distances. The implementation typically involves calculating path loss using the formula: PL(d) = PL(d0) + 10n*log10(d/d0) + Xσ, where n is the path loss exponent and Xσ represents Gaussian random noise. Subsequently, trilateration is applied to determine the coordinates of unknown nodes. This geometric method uses distance measurements from three known reference nodes to calculate the intersection points of circles centered at each reference node with radii equal to the measured distances. The algorithm solves the system of equations: (x-xi)² + (y-yi)² = di² for i=1,2,3 to determine the unknown node's position. This approach enhances ranging accuracy through statistical modeling and geometric constraints, making the overall system more reliable and precise for location estimation.