Advancing time-of-flight technology for high performance light detection and ranging

The goal of the LIANDRI project is to develop the fundamentals for a LIDAR system that does not require any moving parts and, unlike existing systems, measures the propagation time of individual pulses rather than the phase position. Since the pulses will be of very short duration, the power of the pulse can be increased without endagering eyes of pedestrians.

The main focus is to drive a laser diode, more precisely a VCSEL (vertical-cavity surface-emitting laser), with enough power and fast enough so that the light pulse has a length of 10ns in the ideal case, where the current through the laser should be 30-60A. These special properties are to be achieved by using GaN (gallium nitride) technology. GaN transistors have the necessary switching properties to switch high currents in a very short time.

The LIANDRI project includes research on an IC driver component for the optimized control of a GaN transistor and the development of a discrete circuit carrying these components. Furthermore, a timing generator on FPGA will provide control signals to ensure an optimal clocking of the system.

    The Lidar system diagram and prototyp board for the beam