This is the entrance to an abandoned Air Force communications facility just north of Maricopa, Arizona. The facility was part of the Air Force's "space fence" system, a set of transmitters and receivers that detects objects orbiting the earth, including space debris. This and other buildings are clearly visible from the nearby highway (SR 347).

The white sign on the gate says "To enter call 520-315-2226." The chain-link fence (including barbed wire) is still intact and surrounds the facility. Buildings are boarded up, but some doors stand open, as if the buildings are being aired out. Large portions of the long antenna are missing. The facility was vacated in October 2013.

The installation appears in Wikimapia.
More information is in this Wikipedia article.