Bistatic range-gated active imaging in vehicles with LEDs or headlights illumination

Range-gated active imaging systems are more and more used for surveillance and night vision applications. Their ability to improve vision through fog, snow or rain makes them good candidates to be used for automotive safety. But even if they increase safety, expensive options have no chances to come out from the laboratory and to be integrated in a car. Instead of using a complete active imaging system, i.e. a laser diode illuminator coupled with an intensified camera, we propose to control the LED headlights of future cars in a pulsed mode and to synchronize these pulses with a sensitive camera. This paper shows some prototypes we've built and evaluates the performances of these different systems. Furthermore, the problem of sensor saturation due to retroreflecting road signs is investigated and resolved by using a bistatic configuration.