There has been a large variety of mobile robots developed to demonstrate navigation capabilities on rural roads or highways. However a small amount of work focuses on autonomous navigation in densely populated areas depending only on a 16-line LiDAR. In this paper, we present an autonomous navigation system for mobile robot which can be used for delivery, cleaning, surveillance and so on in industrial areas and campus where the environment is unstructured and dynamic. The perception of the environment relies on the 16-line LiDAR installed on top of the mobile robot. The proposed system is composed of three components: LiDAR-based mapping and re-localization module, traversable path and obstacle detection module, and path planning and trajectory tracking module. We tested our system on a real mobile robot that can run autonomously on a campus in a complex environment.