The three components of the GP-1 system accomplish the four major tasks required to produce the screen plot showing the estimated location of lightning activity.
 

Next, the voltage part of the antenna array produces signals that allow identification of the stroke polarity and the stroke type, return or intracloud, signature. Once the Interface circuits have captured the appropriate peak magnitudes and have sent them in digitized form to the computer, the software algorithm selects only the negative return strokes and performs the trigonometry on the magnetic field signals to find the stroke bearing and magnitude. Finally, the stroke magnitude in the bearing is averaged with previous strokes in the same bearing, and the results used to plot the estimated range from the screen map center along the bearing of the current stroke. The screen background is a unique, site-centered map of the surrounding few hundred kilometers.