Lower Tier Air and Missile Defense Sensor The Lower Tier Air and Missile Defense Sensor is a new, advanced sensor developed to integrate into the Army Integrated Air and Missile Defense architecture and will replace the current Patriot radar. SHARE: Download: Full Size (0.21 MB) Tags: Alabama, innovation, Army, Project Convergence Credit: Nathaniel Pierce, Program Executive Office Missiles and Space VIRIN: 231201-O-PF233-3243.JPG Photo Gallery