While both CAIROS and GoalRef use magnetic fields around the goal and need to insert a chip in the ball, Hawk-Eye and GoalControl use a 3D imaging system to determine the precise location of the ball.
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And Shivnarine Chanderpaul was controversially given out to a ball which Hawk-eye predicted would have missed the stumps off James Anderson for 70.
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The controversial Hawk-Eye ball-tracking system, which was developed in England and can accurately call LBWs (leg before wickets), catches and run-outs, is now used in other sports, including tennis.