Computationally simple criteria for detecting a multi-target scenario in automotive radar array processing

The detection of a multi-target scenario in radar-array processing is a crucial step. When only a single source is present, the computationally efficient beamformer for direction-of-arrival (DOA) estimation is sufficient. When multiple sources are present, subspace-based DOA estimation is required to achieve high-resolution and unbiased estimation. To save computational cost, we propose computationally simple criteria for discriminating between a single-target and multi-target scenario in automotive radar-array processing. The suggested criteria can be applied with a single snapshot, and are therefore suitable for classic pulsed radar pre-processing. We present an empirical analysis of the proposed criteria, and show results with real-life data.