English: Bell Labs described the new Multi-function Array Radar in a 1962 edition of their internal journal. The image shows a system with two "faces", each providing coverage over about 150 degrees in azimuth. The smaller domes are the transmitters, while the receivers shared the central dome. The image appears to show construction on two additional faces underway, or ongoing construction on the underground building that hosted the enormous computer systems and power generators needed to run it. The original testbed system, sometimes known as MAR-I, was built in almost exactly this form at White Sands Missile Range in New Mexico. MAR-I was built for two faces, as in this image, but only one was installed. The only major differences between this image and MAR-I was built is that the transmitter domes are smaller, moved closer to the main receiver dome, and moved in relationship to the receiver. In this image if one stands in front of the receiver facing outward, the transmitter is on the right. MAR-I moved the transmitter to the left.