This book starts with the introduction of the radar working system from a mathematical point of view. It shows the composition of transmitted signal and echo signal, and describes the principle of speed measurement and distance measurement for different radar systems. The book focuses on millimeter-wave radar technologies related to echo signal denoising, target identification, clustering, and target tracking and develops a workable plan for the information fusion idea between millimeter-wave radar and machine vision. This book breaks down the systematic processing flow of millimeter-wave radar echo signals one by one from the standpoint of intelligent transportation, concentrating on the introduction of principles and reinforced by a plethora of experimental instances. So that readers from all relevant professions may comprehend millimeter-wave radar's involvement throughout the complete system process.