A method and apparatus for automatic down-hole asset monitoring is provided that monitors tagged down-hole assets wherein the assets travel into and out of an oil or gas well. A rig reader system, a controller and a computer incorporating a graphic user interface are connected to monitor tagged assets moving into and out of a drill head. The rig reader portion may be a ring shaped device having therein an integrated antenna array and radio frequency identification interrogators that interrogate an SAW or RFID tag as it moves through the ring shaped device. The integrated antenna array may include evenly distributed antennas about an interior surface of the ring shaped device that are covered by a radome that seals the antenna array and interrogators against contamination from caustic chemicals and other substances found on or around an oil rig platform. The ring shaped rig reader may be mounted directly below or above a rotary table or a rig's floor or be between a well head of an oil and gas well and the rig floor. The rig reader of an exemplary rig reader system is adapted to withstand a wide temperature range, caustic chemicals, shock and vibration and other elements commonly present on and about an oil or gas rig.