The US Army acquired seven PQM-102As for use in evaluation of the Stinger and SAM-D (later named Patriot) surface-to-air missiles. Most of the remainder were used by the USAF at Tyndall AFB and Holloman AFB.
No Longer There
The later PQM-102B had improved systems and added a low-altitude mode (for altitudes down to 60 m (200 ft)), for which a radar altimeter was installed. By relocating the electronics, the cockpit of the PQM-102B could reportedly be kept free for optional manned operation.
The last PQM-102B (56-1072) was expended at Holloman AFB in 1986.
I'm guessing that this one may be used in conjunction with the rocket sled off just to the west.