SMALL SIZE, MULTI-FREQUENCY, MULTIBEAM PHASED ARRAY ANTENNA SYSTEM

Satellite communications, Airborne radar, EW, and Communications systems differ significantly in their antenna requirements. Not only do the various systems differ in their primary functions, but the many variations within one system will affect antenna requirements. For example, an airborne radar system may be configured functionally as a tracking, search and track, altimeter, navigation, ground mapping etc. Each of these radar systems has aperture reuirements unique to its function as modified by location on the airborne platform. Additionally, radars and communications require both transmission and reception of energy where as ESM and ECM systems require only reception of energy. With the availability of a mature monolithic microwave based Transmit/Receive modules it is now possible to look at alternative concepts. The availability of the T/R modules alone is not sufficient if a low cost shared aperture antenna is to be realized. Innovative front end partitioning and use of other technologies, such as multilayer printed circuit microwave technology or low temperature co-fired ceramics needs to be incorporated. For an antenna to acquire two simultaneous satellite links in the X-band, C-band and KU-band requires an innovative concept that will compete with the single parabolic concept. It is distant satellite, is determined by the aperture of the antenna. Any elements introduced behind the antenna aperture, such as filters or amplifiers with a known loss or noise figure, will degrade the subsequent signal to noise ratio. Active phase array radars require solid state T/R modules with high output power, low noise figure, high third order intercept and innovative concept with an architecture that requires a minimum number of the active components. The Multibeam Array approach proposed under this Phase I SBIR can be utilized for either the narrow or wideband arrays. The capability for wideband power splitter or feed network and a wideband antenna elelment. The specific technical objective of the Phase I SBIR proposd herein examines the critical issues that will make a Multibeam aperature phase array antenna a practical technology. The requirement to opearate several systems simultaneouslyf rom a common aperature can be achieved by using a control circuit at each element. The control circuit consists of an arrangement of a multiplexer, an attenuator and a phase shifter. The multiplexeer is used to partition the aperature into several simultaneously operating anten