Antenna Array Design for Coherent MIMO Radar Networks

High angular resolution provides improved environmental perception and increases the detection quality of extended targets. It is therefore a key requirement towards future radar systems for autonomous driving. The angular resolution of a radar system fundamentally depends on its antenna array aperture size. It is technically difficult and economically challenging to realize a large aperture radar system as a single sensor. Radar networks, consisting of multiple individual radar sensors, mitigate the challenges caused by creating a large aperture radar system. This paper presents a radar network consisting of two individual MIMO radar sensors equipped with L-shaped physical antenna arrays. L-shaped arrays for the individual sensors are chosen to achieve a rectangular equally spaced radar network vir-tual aperture. Furthermore, the paper discusses the performance of the resulting virtual aperture in the context of DoA estimation. Measurements of a bicycle, conducted with a coherently coupled radar network consisting of 768 virtual channels, demonstrate the performance of a high angular resolution radar system.