A method and system of disabling a remote improvised explosive device (IED) that is triggered by a cell phone. A portable wideband network system, installed in a vehicle, is used to determine operator frequency or frequencies active on a route along which the vehicle will travel. The vehicle includes a wideband transmitter for raising a radio frequency noise floor across all of the active cellular frequencies in a limited area surrounding the portable wideband network system during passage along the route. A notch filter is used by the system for filtering a particular frequency from the noise floor. The power level of the portable wideband network system is increased so that the strongest signal at the particular frequency in the limited area is provided by the portable system's base station. All mobile terminals in the limited area around the vehicle are connected to the portable system and the portable system prevents call completion of any of the connected mobile terminals.