Arbitrary Angle of Arrival in Radar Target Simulation

Automotive radar sensors play a key role in the current development of autonomous driving. Their ability to detect objects even under adverse conditions makes them indispensable for environment-sensing tasks in autonomous vehicles. The thorough and in-place validation of radar sensors demands an integrative test system. Radar target simulators (RTSs) are capable of performing over-the-air validation tests by creating artificial radar echoes that are perceived as targets by the radar under test (RuT). Since the authenticity and credibility of these targets are based on the accuracy with which they are generated, their simulated position must be arbitrarily adjustable. In this article, a new approach to synthesize virtual radar targets at an arbitrary angle of arrival (AoA) is presented. The concept is based on the superposition of the returning signals of two adjacent RTS channels. A theoretical model describing the basic principle and its constraints is developed. Additionally, a measurement campaign is conducted that verifies the practical functionality of the proposed scheme.