The U.S. Missile Defense Agency (MDA) on April 13 unveiled its long-awaited acquisition strategy for a constellation of missile-tracking satellites, which includes the development and launch of a prototype system in 2015 prior to beginning work on as many as a dozen operational satellites.

The MDA for years has been interested in the so-called birth-to-death tracking of ballistic missiles from space. Last year the agency launched three demonstration satellites — one classified and two unclassified — under a program called the Space Tracking and Surveillance System. The unclassified satellites are going through on-orbit check-out activities and have yet to observe a ballistic missile flight test.

For the new Precision Tracking Space System (PTSS) announced by the agency in 2009, the MDA will rely on the Johns Hopkins University Applied Physics Laboratory of Laurel, Md., to lead a prototyping effort, according to a posting on the Federal Business Opportunities Web site. As many as five industry teams will be chosen in 2011 to provide input for the design of the system. Other opportunities may exist to provide hardware for the PTSS prototype, the posting said.

A single contractor will be chosen in 2014 to build between nine and 12 operational PTSS satellites and ground-segment software for integrating the satellites into the national ballistic missile defense architecture, the posting said. Production will not begin until after the prototype is launched and demonstrated on orbit.

Unlike the Space Tracking and Surveillance System that operates in low Earth orbit, each PTSS spacecraft will stare continuously at one region from a position along the geostationary belt, Army Lt. Gen. Patrick O’Reilly, the MDA’s director, told lawmakers during an April 15 hearing. The MDA has requested $67 million for PTSS in 2011.