A gravitic sensor net is a type of sensor grid employed by Federation border outposts to detect cloaked ships in the 2360s. It was not considered completely effective, and was eventually supplemented by the tachyon detection grid. (TNG: "Face of the Enemy")

Cloaking penetration technology
Antiproton beam • Gravitic sensor net • Long-range tachyon scanner • Metaphasic sweep • Quantum beacon • Tachyon detection grid