GPS signals are very weak and so vulnerable to jamming environment. To solve this problem, anti-jamming technology based on array antenna has been widely studied. Especially, beamforming technology shows the best anti-jamming performance to make a beam toward each tracking satellite and a null toward to the direction of a jamming signal. The beamforming technology generally uses a 2-dimensional planar array antenna and steers the beam to the satellite direction on the line of sight. However the satellite signal blocking occurs when the air vehicle is rotating, raising or lowering. So it affects the satellite tracking status and signal-to-noise ratio. In this paper, we propose the model of 3-dimensional array GNSS antenna and the performance is evaluated by simulation. In simulation result, proposed modeling reduces the signal blocking loss effect on rotating, rising and lowering of the air vehicle and enhances the beamforming performance in multiple jamming.

Keywords: 3-dimensional array, beamforming, blocking loss