sry, aravind. Arc array means antennas have to place in arc shape, not to draw arc (take arc type sheet). Anyway thanks for your answer.

Here i tried with dipole antennas as array elements.

the difference may be due to mutual coupling between antenna elements in the array. a little difference is acceptable.

I recomment you to use the second method ( without using far field array and creating each antenna in array) since it is more accurate.

Thank you Ali Shahi