FMCW: Frequency Modulated Continuous Wave Lidar Systems

In this article, we provide a comprehensive examination of FMCW lidar systems and their applications in autonomous driving technology. FMCW lidar represents a laser-based ranging technique that operates by emitting frequency-modulated continuous wave laser signals and analyzing the reflected light to calculate distances between objects and the lidar system. This sophisticated approach implements signal processing algorithms that typically involve Fourier transform analysis to extract precise distance and velocity information from the phase differences between transmitted and received signals. Key implementation aspects include coherent detection methods where the system mixes the transmitted and received signals, generating beat frequencies that correspond to specific distance measurements. The system's notable advantages include high precision, exceptional resolution, and superior interference resistance, making it particularly valuable for autonomous driving applications. In self-driving vehicles, FMCW lidar systems employ sophisticated point cloud generation algorithms to create real-time 3D environmental maps, enabling vehicles to perceive their surroundings with millimeter-level accuracy. The system architecture typically incorporates digital signal processing (DSP) components that handle complex mathematical operations for real-time data analysis. These systems facilitate critical autonomous functions including object distance measurement, velocity calculation through Doppler shift analysis, and dynamic target tracking using Kalman filter implementations. The integration of FMCW technology provides essential support for advancing autonomous driving systems by delivering reliable environmental perception capabilities required for safe navigation and decision-making processes.