A dispersion field, or dispersal field, was a type of energy emission which could block sensors and transporters. In 2152, the Torothans, who suspected the crew of Enterprise NX-01 of collaborating with dissenter Zobral, activated an orbital dispersion field utilizing a series of artificial satellites, in order to prevent the crew from detecting anything on the surface below one hundred kilometers. Although the field covered approximately one half of one of the planet's continents, Lieutenant Reed managed to devise a plan whereby he could get clear readings by disabling three of the satellites. Sub-Commander T'Pol, however, overruled this plan, believing that such an action would provoke the Torothans into taking aggressive actions against Enterprise. (ENT: "Desert Crossing")