Automotive In-Cabin Radar Uncovered: The Essential Guide to Choose the Perfect Sensing Technology for Your Vehicle

In-cabin monitoring systems (iCM) are transforming the automotive industry’s approach to safety and occupant well-being. Among the various sensing technologies, radar has emerged as a highly effective solution due to its robustness in challenging conditions such as poor lighting or obstructed view. This article reviews the state-of-the-art radar technologies used for critical automotive safety applications, including child presence detection (CPD), seat belt reminder (SBR), intrusion detection systems (IDS), occupant out-of-position (OOP) analysis, and vital sign monitoring. With emerging regulatory requirements, such as the European New Car Assessment Program (Euro NCAP) standards mandating CPD and SBR, radar technology provides a scalable, cost-effective solution for automakers. This article examines the underlying radar principles, system architectures, capabilities, and limitations of the three main used radar technologies [Doppler, frequency modulated continuous wave (FMCW), and ultrawideband (UWB)] for iCM, addressing both technical challenges and opportunities for enhancing vehicle safety.