Design of a DoA Approach for a 140-GHz Automotive Radar Employing Beam-Scanning Patterns

Abstract

Automotive radar systems increasingly operate in an occupied frequency spectrum, raising concerns about mutual interference among radar sensors. Moving from the widely used 76–81 GHz frequency range towards 140 GHz provides a possible way to address this increasing interference. Operation at this frequency, however, introduces higher propagation losses and requires higher antenna gain to accommodate medium-to-long detection ranges. The resulting directional antenna responses require beam scanning to cover the required field of view, creating challenges for angular estimation under the timing constraints of automotive radar.

This thesis investigates single-snapshot direction-of-arrival estimation for beam-scanning radar systems. A simulation framework is developed to model the considered radar architecture and evaluate different estimation approaches under representative operating conditions. The methods are assessed through Monte Carlo simulations considering estimation performance, detection performance, target separability and convergence behaviour across different signal-to-noise ratios and target configurations.

The results demonstrate that the available beamspace information can support accurate single-snapshot direction-of-arrival estimation and separation of closely spaced targets. The investigated methods provide different trade-offs between estimation performance, angular resolution and computational complexity. The developed framework is not restricted to a particular antenna design and can support the investigation of different beam configurations and beam-scanning applications.