mm-Wave Antenna Array Modeling for Autonomous Vehicle Radar Applications
(Room Ballroom G)
18 Oct 18
2:40 PM
-
3:10 PM
Wireless systems will provide a variety of communication, information, sensor and safety functions for the streets of the future. The advent of autonomous vehicles will drive the need for multiple sensors, spanning microwave and millimeter wave radar, as well as visible and infra-red spectra. ADAS and Autonomous vehicle systems are likely to require at least 6 radar systems to monitor traffic and to perform safety functions to ensure the safety of the passengers. These safety systems will be effective and efficient, giving autonomous and human-drive vehicles instantaneous reflexes to react to sudden and unanticipated dangers and to take evasive action. In addition, radar sensors in the future are likely to have a significantly higher degree of functionality, with ability to image the road scene, detect and track objects and obstructions, and to locate safe paths through unfolding hazards. These radars will be able to monitor road conditions even locating and reporting potholes and debris on the road. In this work, and with the use of computer-aided engineering software, engineers can develop and validate advanced radar designs from synthesizing, optimizing and evaluating radar sensor designs to evaluate their interactions with vehicle structural components like the fascia, bumper or grille. A candidate design for a front-mounted medium-range 77 GHz radar system is demonstrated for monitoring forward traffic and objects within a distance of 50m, with object location accuracy of 0.1m and object velocity measurement precision of 0.2 m/s. Modeling the installation effects of the radar sensor, including the defocusing effect of bumpers, fascia and grills is also presented. Analysis of the radar module and its installation location can affect the radar’s ability to detect the direction of an object, as well as to reduce the radar’s sensitivity to objects that are more difficult to detect. Factors such as bumper material composition, paint and lacquer layers, and weather effects like rain, ice, dust and mud can be evaluated for their impact on the radar’s performance. This paper will illustrate the design process of an antenna array at 77GHz. The antenna design must tightly control the distribution of radiation energy, focusing it on the areas of the road under observation and minimizing energy broadcast to location that are not of interest to the sensor. The antenna array is then placed on a virtual vehicle, in a virtual world and evaluated as a complete radar system. With the use of an advanced shooting-and-bouncing ray analysis technique, we could evaluate the performance of a radar in the presence of an extended road containing vehicles, stationary objects, and other structures found on a road scene to test the signals and target indications that would be returned by a sensor design. This is a powerful technique for evaluating radar performance and evaluating it in a complete simulation loop involving the radar sensor, detection algorithms, advanced safety systems, vehicular control systems and vehicle dynamics. The radar system performance is often displayed in terms of a series of range-Doppler maps.