A LIDAR system, comprising: (a) a plurality of anchored LIDAR sensing units, each anchored LIDAR sensing unit comprising at least: (i) a housing; (ii) at least one detector, mounted in the housing, configured to detect light signals arriving from objects in a field of view of the anchored LIDAR sensing unit; and (iii) a communication unit, configured to output detection information which is based on outputs of the at least one detector and which is indicative of existence of the objects; and (b) at least one integratory processing unit, configured to receive the detection information from two or more of the plurality of anchored LIDAR sensing units, and to process the received detection information to provide a three dimensional model of a scene which is larger than any of the field of views of the independent anchored LIDAR sensing units.