Automotive system designers develop sophisticated LIDAR systems to automatically control vehicle speed and braking systems according to traffic conditions. Such systems can also dynamically control distance from other vehicles and obstacles and even manage safety features such as airbags. Automotive Laser-based obstacle recognition systems (LIDAR) which is now entering high volume production. Automotive LIDAR sensors represent key components for next generation driver assistance functions. LIDAR sensors show large sensitivity towards environmental influences (e.g. snow, fog, dirt).

LIDAR (Light Detection And Ranging) systems using the same principle as RADAR are developed for a wide range of locating, ranging, and profiling applications. Such a system consists of a laser capable of transmitting light (pulsed or continuous) over the required range of interest, and a high-speed, low-noise receiver for reflected signal analysis. Transmitted light interacts with and is changed by the target. A percentage of this light is reflected / scattered back to the receiver according to the reflectivity of the target. Changes in the properties of the transmitted signal enable some properties of the target to be determined. In the most common application, the Time Of Flight (TOF), is used to determine range.

LIDAR systems employ an invisible laser in the rear view mirror illuminating an area of about a few meters in front of the car. The reflected light from obstacles such as cars or pedestrians in close proximity is used to measure the distance. If the distance is too small, the system initiates automatic braking. LIDAR systems are among the first active safety features coming into volume production.

Laser sensors are common devices for today’s vehicle environment recognition tasks in Active Driver Assistance Systems (ADAS) applications. The advantages of active scanning laser sensors are a high range of measurements for distance and horizontal field of view as well as its high spatial resolution. These are very attractive features for an automotive environment detection sensor.

To fully exploit the potential of LIDAR technology and Laser sensors, custom signal processing algorithms have to be developed. Recent and future approaches for laser based vehicle environment recognition have to address and solve also challenges like multipath propagation, multi-echo signals and backscatter from road surface. One practical problem what researchers and engineers are facing today is the disadvantageous influence of the vehicle’s dynamics on the laser measurements. The problem introduced in this situation appears as false measurements generated by the road surface or as a wrong estimated height of obstacles in the vehicle’s environment. This behavior has e.g. recently been observed in a Pre-Crash safety related research project.