Micro‐motion of a moving train observed by a Ka‐band interferometric radar

A moving train was imaged by a Ka‐band interferometric (In) radar of 2 GHz bandwidth working at the dechirping model. Two radar images from two channels as well as their In image were obtained after estimating the speed and direction of the train. The plots of In phases (InPhes) along the train exhibits periodic fluctuations, which are resulted from the back and forth motions of both locomotive and other compartments when the trains are moving ahead, and this can be attributed to the micro‐motion (m‐M) of the train. As far as it is known, this is the first time to experimentally demonstrate m‐M detection through InPhes.