A phased array feed, dual offset reflector antenna for testing array compensation techniques

A design of a phased-array-feed, dual offset reflector antenna for testing the concept of extending the antenna field of view (electronic beam steering range) by adjusting the array element phase shifters to compensate for optical aberration is presented. The test article is envisioned to be a small replica of the near field feed, offset Gregorian reflector antenna frequently conceived for narrow field of view systems. The test article feed array was sized to match an available 5 lambda square (approximately) MMIC (monolithic microwave integrated circuit) planar array. The array contains a MMIC T/R module with a controllable digital phase shifter for each of 104 radiating elements. A detailed analysis of the design was performed with the physical optics based program ARCREF. The results obtained clearly demonstrate that the MMIC array can be used in an experiment to verify that appropriate adjustment of the feed array phases for an array feed reflector system can recover much of the gain loss with scan attributed to optical aberration.<>