BALL SPIN RATE MEASUREMENT

摘要

Spin rate measurement utilizing periodic phase modulation of the radar Doppler signal reflected from a golf ball is described. Some embodiments provide a method to directly measure the ball spin rate caused by the symmetrical structure of the golf ball seam, using the dielectric lens effect of a practical sports ball to magnify the modulating effect of a non-homogeneous feature on the ball, and utilizing the specific pattern of modulation caused in this manner.