Packaging of multibeam spatially-fed antenna arrays

Discrete lens antenna arrays (DLAs) have been introduced for multibeam applications. In a DLA, two antenna arrays, in which element pairs are connected with true time-delay lines of varying length across the array, perform a discrete spatial Fourier transform. The lens array produces a focal surface along which feed antennas are placed, each corresponding to a beam in a different direction. The DLA can be used to transmit, receive or both. The DLA is a three-dimensional device with planar, typically multilayer, lens antennas, and a curved focal surface. Packaging the feed antennas along the focal surface needs to be solved, and some issues related to this problem are the focus of the paper. Radiation patterns of feed antenna elements have been measured with and without an absorber placed in the focal volume. A package has been designed to house over 20 beam feeds for a lens array to be used an X-band satellite ground station application.