Multifocal LIDAR Systems

Ürkmen, Koray
LIDAR systems are commonly used in automation applications, autonomous vehicles, military systems, and other new application areas that are increasingly expanding with the recent developments in LIDAR technology. LIDAR systems are used for getting 3 Dimensional information about the target which is very important for most of the advanced systems and algorithms that are used for the recognition and identification of objects. The most well-known distance measurement techniques for LIDAR systems are the direct “time of flight” (ToF), AMCW (Amlitude Modulated Continuous Wave), and FMCW (Frequency Modulated Continuous Wave) range measurement techniques. In the direct ToF technique, depth resolution is limited by the rise time of the transmitted pulse and measurement speed of the LIDAR system. AMCW and Linear Chriped AMCW techniques are limited in maximum measurement range by ambiguity. FMCW technique needs high-speed electronics with a single pixel resolution and its maximum measurement range is limited by the coherence length of the light source. This study, it is aimed to achieve up to mm scale depth resolution capability at a medium target range by combining multifocal imaging concepts with LIDAR measurement techniques. With this study, Multifocal LIDAR Imaging techniques with higher resolution, have been first introduced, designed, and analyzed. The results show that, with the introduced Multifocal LIDAR Imaging technique, a good improvement has been achieved in depth resolution for the direct ToF technique and measurement range for the AMCW technique without decreasing the depth resolution of AMCW. Introduced new techniques by this thesis can have a large application area such as robotic applications.


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Citation Formats
K. Ürkmen, “Multifocal LIDAR Systems,” Ph.D. - Doctoral Program, Middle East Technical University, 2022.