Airborne Laser Scanners
The range finder electronics (1) are optimized in order to meet the requirements of high speed scanning (high laser repetition rate, fast signal processing and high speed data interface).
The angular deflection of the laser beam (2) is realized by a rotating polygon (3) with a number of reflective surfaces. It continuously rotates at an adjustable speed to provide a unidirectional scan.
For every measurement RANGE, SCAN ANGLE, SIGNAL AMPLITUDE, and optionally a TIMESTAMP are provided via a TCP/IP Ethernet interface (4). The Scanners are prepared to accept a TTL-signal (i.e., 1 pulse per second) from, e.g., a GPS receiver, to reset an internal timer, which is used to timestamp every measurement.
The RIEGL LMS-Q-560 as well as the LMS-Q680i give access to detailed target parameters by digitizing the echo signal online during data acquisition, and subsequent off-line waveform analysis (5). The sampled full waveform data is stored while data-acquisition on a digital data recorder (6) via a high speed serial data link cable (7).
The RIEGL VQ-Line airborne laser scanners offer multiple target capability by online waveform analysis based on echo digitization. No digital data recorder and off-line waveform processing is necessary.