Height–angle map of CME front distribution in polar coordinates for extracting geometric quantities used in parameter estimation. The horizontal and vertical axes denote the polar angle and radial height, respectively. The distribution of the CME front is used to determine the maximum height (﹩{H}_{{\rm{\max }}}﹩), AW, and CPA, where ﹩{H}_{{\rm{\max }}}﹩ is further used to construct the height–time curve for propagation-speed estimation.