Sensor-Net is an effective mobile device detection system for prisons, government buildings, and other high security areas. It is intended for areas where mobile communication is unauthorized. Sensor-Net detects and informs the operator of transmissions including: incoming or outgoing calls, text messages and device registration and location. The Sensor-Net detectors can be strategically placed throughout a facility and covertly installed inside a number of innocuous devices such as smoke detectors and closed circuit TV cameras. Sensor-Net detectors, which come with internal omni-directional antennae and will cover all mobile phone systems, provide feedback to a central unit via a network connection. Each detector can be configured to cover any range up to 100 meters, depending on the required location and environmental conditions.