High-Density Implementation Techniques for Long-Range Radar Using Horn and Lens Antennas

Abstract

Long-range radars (LRRs) for higher level autonomous driving (AD) will require more antennas than simple driving assistance. The point at issue here is 50-60 % of the LRR module area is used for antennas. To miniaturize LRR modules, we use horn and lens antenna with highly efficient gain. In this paper, we propose two high-density implementation techniques for radio-frequency (RF) front-end using horn and lens antennas. In the first technique, the gap between antennas was eliminated by taking advantage of the high isolation performance of horn and lens antennas. In the second technique, the RF front-end including micro-strip-lines, monolithic microwave integrated circuits, and peripheral parts is placed in the valley area of each horn. We fabricated a prototype LRR operating at 77 GHz with only one printed circuit board (PCB). To detect vehicles horizontally and vertically, this LRR has a minimum antenna configuration of one Tx antenna and four Rx antennas placed in 2×2 array, and 30 mm thickness. Evaluation results revealed that vehicles could be detected up to 320 m away and that the horizontal and vertical angle error was less than +/-0.2 degrees, which is equivalent to the vehicle width over 280 m. Thus, horn and lens antennas implemented using the proposed techniques are very suitable for higher level AD LRRs.

Automated Lane-Level Road Geometry Estimation Using Microscopic Trajectory Data

“…To date, few studies have been published on the subject of long-wide trajectory data collection systems, particularly those that are environment-insensitive [9]. Long-range millimeter-wave (MMW) radars have been recognized as having weak atmospheric attenuation and the ability to achieve over 200 meters of sensing and detection [36]. In this study, we apply the above method to the trajectory data of a MMW radar.…”