SDK: v2.3
I read the documents : 
It described" If there is no antenna toggling, then the I/Q samples will form a perfect sine wave." So I change the antenna toggling pattern from 2 antennas to 1 antenna(A1.2). And the I/Q plot is as the attached picture.
But it seems like 17 samples formed a perfect sine wave? But is should be 16 samples? And SDK v2.3 use 0~7 as valid samples to calculate phase difference.
