A method and an antenna array for determining polarization state of a signal. The method includes adjusting a plurality of orthogonal antenna elements. The adjusting the plurality of orthogonal antenna elements includes measuring a first amplitude of the signal at a first incident angle. Further, the method includes measuring second amplitude of the signal at a second incident angle. The second incident angle is obtained by rotating the at least two antenna elements from the first incident angle to the second incident angle. Then the method includes measuring third amplitude of the signal at a third incident angle. The third incident angle is obtained by rotating the at least two antenna elements from the second incident angle to the third incident angle