# 빔포밍 기법을 이용한 GPS 재밍 대응

Choi, Chang-Mook
최창묵

• Accepted : 2015.11.19
• Published : 2016.02.29
• 17 16

#### Abstract

Because GPS signals are weak, system jamming is a real and present danger. This can happen when the receiver is subjected to intentional or unintentional interference by a transmitter. If the jamming signal is strong enough, the receiver can be operated to take corrective action automatically. Current methods to protect GPS receiver from jamming condition are based on spatial filtering. In this paper, the beamforming as referred to in signal processing technique used in arrays for directional signal reception was suggested and analyzed for anti-jamming. In order to change the directionality of the array when receiving a jamming signal, a beamformer can control the signal at each sensor. Therefore, cutoff angle ${\theta}$ was measured in the opposite direction of the jammer. GPS signals are only processed when the antenna element is within inside the cutoff angle. As a result, GPS positioning can be used in condition under cutoff angle $30^{\circ}$.

#### Keywords

GPS;jamming signal;spatial filtering;beamforming;anti-jamming.

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