This paper describes a novel and low-cost scheme for automotive precollision sensing called BARBI, an acronym for BAseband Radar Bag Initiator. An extension of this technique is also suggested for braking applications. The proposed technique involves the transmission and reception of a subnanosecond baseband or video impulse-like signal (i.e., no RF carrier) and requires virtually no microwave components. The very fast signal risetime permits leading edge resolution on approaching vehicles of much less than a foot; closing velocity is obtained by using range-rate techniques. By incorporating sequential range gating techniques, the false alarm rate can be reduced to less than one in ten years for all the cars in the U. S. today.