Geometry Design Optimization of Large-Scale Broadband Antenna Array Systems

The next generation radio telescopes such as the Square Kilometer Array (SKA) are expected to contain thousands of antenna array elements operating over a broad frequency range where the signals from each antenna element are combined and processed simultaneously providing high sensitivity with multiple beams providing a wide field of view. One crucial design aspect influencing both the performance and the cost of such systems is the array geometry. Due to the large bandwidth and number of broadband antenna elements, the optimization of such array system is difficult to achieve with the current array geometry optimization techniques which rely mainly on genetic algorithms and pattern search techniques. This paper provides a study of the effects of array geometry on the performance broadband array system. In addition, it provides a method where the array geometry can be more easily optimized for different applications. This is demonstrated for optimizing a typical SKA station in the frequency band between (70-450 MHz).

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