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A way to design the STC performance for automotive millimeter-wave radar is proposed. With a statistical analysis on the data achieved in an experiment at a practical driving situation, the probability distribution of the received signal according to the distance is obtained. The experiment was carried out using FM-pulse Doppler radar we developed. Based on the obtained characteristics, a necessary compression of radar dynamic range is specified. With designed STC in the proposed way, the cost of the radar has been reduced while achieving a wide detection area up to 150m.

We have many traffic accidents and related fatalities every year and safety issue is focused very much as well as environmental issue. As for frontal collision, some products of Adaptive Cruise Control (ACC) System and headway distance warning system have been developed and introduced to the market in Japan, U.S, and Europe. In the other hand, the systems to reduce side and rear collision, for example, which assist driver's maneuvers in lane change situation at high speed, are under development. And efforts to make restraint systems such as airbag and seat belt more effective is also needed in order to increase passive safety and reduce related fatalities, for example, smart airbag using additional sensors. Corresponding to these situations, we made a plan to develop short-range radars for these automotive applications, Blind Spot Detection System (BSD), Parking Aid System (PA), and Pre-crash Detection System (PC).

The vehicular collision avoidance millimeter-wave radar that uses an FM-pulse Doppler method is proposed. This radar is constituted with the FM-CW radar method and the pulse Doppler radar method. This radar method has combined the advantages that the precision of the measurements of distance and speed of the target that the FM-CW radar method provides, and the low target mis-recognition probability that the pulse Doppler radar method provides. The millimeter-wave radar using this method was produced using comparatively simple circuits The experimental data that was obtained with this radar and with the FM-CW radar are compared with each other. The effectiveness of the FM-pulse Doppler method was investigated using data obtained from on the road environment using a target vehicle and some objects.

Vehicular collision avoidance radar systems using millimeter-wave have been developed in recent years. Because of their simple structures, a microstrip antenna or a lens antenna is often used as the radar antenna. However, the antenna efficiencies of these antennas are low, in general. Therefore, the types of antenna that have small antenna aperture are difficult to obtain high antenna gains. In addition, it is difficult to radiate many beams at narrow beam intervals with a lens antenna. We developed an offset paraboloidal reflector antenna (the OP antenna) for the vehicular collision avoidance radar. This antenna consists of one pyramidal horn antenna and one offset paraboloidal reflector. They pyramidal horn and the radio frequency unit (the RF unit) of the radar are fixed in the radar head. To scan the beam, only the reflector is rotated. Using a reflector-rotating mechanism, the OP antenna can radiate many beams toward different directions.

This paper relates to a distance detecting sensor, specifically a scan radar laser used for a vehicle distance warning system or an intelligent cruise control system. In developing the scan laser radar, we used a light-based scan-action system working via an electromagnetic actuator and ICs in place of the internal circuitry for substantial parts count reduction. The compact scan laser radar is smaller in size and lower in price with higher performance than its predecessors (1). This has made it possible to offer a lower-priced, compact, lightweight, and easy-to-install scan laser radar.

An offset paraboloidal reflector antenna for vehicular collision avoidance radar is designed and evaluated. The antenna is designed to use at 77GHz band, and to have suitable gain and beamwidth for the vehicular collision avoidance radar. The properties measured and calculated are compared and confirmed to agree well. The offset paraboloidal reflector antenna is low-loss and has large degree of freedom of antenna design, compared with such as a microstrip antenna. So, using this type of the antenna for the radar system contributes to miniaturize, to make light weight, and to be easily mass-produced of the radar system.

This paper is concerned with a scan laser radar sensor used to measure distance. It s a basic component of a vehicle distance warning system or an intelligent cruise control system. An intelligent cruise control system requires not only the distance to the object, but also the ability to detect movement of the preceding vehicle and the existence of any other nearby obstacle. However conventional radar sensor mainly fixed beam technology and measure only distance. Therefore, it s insufficient for the application to an intelligent cruise control system. Our newly developed scan laser radar transmits an extreme narrow beam and scans both transmission direction and reception direction simultaneously at a high measurement time rate. This scan laser radar can measure the lateral position of objects with high accuracy and good reconstruction level.

In vehicle distance warning systems using fixed beam laser radar false alarms often occur on curved roads. To solve these problems, we attempted to detect the target vehicle correctly by using a scanning laser radar on curved roads. This scanning laser radar has the advantage that it is able to measure the distance and direction of obstacles on roads. In this paper, we explain the following three items. The first is the configuration of the experimental system which we developed. The second is the method of target vehicle detection by using reflectors located along roads. The third is the performance of this experimental system.