Antenna of an airborne multimode RSA

The design principle of a transmit - receive X-band antenna for an airborne multimode radar with synthetic aperture are considered. This antenna provides three functional modes of radar at the expense of three radiation pattern sets. Elements of an original system for antenna position are developed, which permit to diminish a loss in transmit mode and to stabilize the radiation pattern beam in space with high accuracy when a vehicle flight is non-stationary. A loss diminish is achieved at the cost of using hinged-waveguide joint in place of corrugated waveguide in transmit channel, as this were up to date. Accuracy stabilization of the radiation pattern beam in space is achieved with help of three-movable rods instead of cardan suspension, what enable to diminish of a radome size. Antenna aperture is consist of a four section, two of which are located in azimuth plane, and two other ones in elevation plane. This permit in radar to diminish a minimal detectable velocity of targets and to implement the new functional mode - a lay of land determination. The photo of antenna aperture and measured radiation pattern are given.