http://sls.iykpqm7jiradoeezzkhj7c4b33g4hbgfwelht2evxxeicbpjy44c7ead.onion/technologies/cell-site-simulators-imsi-catchers
Cell-site simulators operate by conducting a general search of all cell phones within the device’s radius, in violation of basic constitutional protections. Law enforcement use cell-site simulators to pinpoint the location of phones with greater accuracy than phone companies and without needing to involve the phone company at all.