Patent — available for licensing
More Reliable Doppler Lidar for Autonomous Navigation
A NASA invention available to explore as a licensing opportunity.
About this technology
Overview
NASA pioneered Navigation Doppler Lidar (NDL) for precision navigation and executing well-controlled landings on surfaces like the moon. This advanced lidar system utilizes Frequency Modulated Continuous Wave (FMCW) technique with homodyne detection to simultaneously determine distance to targets and velocity between the sensor and target. However, homodyne detection cannot provide phase information needed to determine the sign (+/-) of signal frequencies, resulting in false measurements of range and velocity. NASA has developed an operational prototype (TRL 6) that integrates non- mechanical beam steering with a novel algorithm to solve this critical problem. Using a three-section waveform and non- mechanical liquid crystal beam steering, the system scans the laser beam to generate 3D images while an ambiguity mitigation algorithm analyzes historical phase information to resolve frequency sign ambiguities and recover valuable measurement information from compromised signals. This complete solution enables reliable velocity and range imaging for autonomous navigation in space, air, and ground applications.