A compact dual-purpose antenna

A small, flush-mounted structure, serving as a radiator for two widely separated frequency bands, has been developed to fulfill the requirements for use in high-speed vehicles. The radiator can be utilized alone or as an element in an array to produce many different radiation distribution characteristics. The element was designed to withstand the severe environments encountered in modern airborne vehicles. It was also designed to withstand, without electrical breakdown, applications of large amounts of r-f power under ambient pressures corresponding to high altitudes.