LiDAR (Light Detection and Ranging) is a non-destructive remote sensing technique for the measurement of distances and provides a relatively novel tool for generating a unique and comprehensive mathematical description of the target (e.g. vegetation and infrastructure). LiDAR measures the properties of scattered light to determine the range and other information of a distant target (Wehr & Lohr, 1999).
The prevalent method is the use of laser pulses, with frequencies in excess of 150 kHz. The distance between the sensor and the target vegetation can be measured by either measuring the time that a laser pulse takes to travel between the sensor and the target (time-of-flight LiDAR) or measuring the phase difference between the incident and reflected laser beams (phase-shift measurement LiDAR).