A novel strategy for interpreting multiple responses in vehicle radar: A novel consideration of the ambiguity function

Frequency modulated continuous wave (FMCW) vehicle radar presents severe range-velocity ambiguity due to the velocities and ranges encountered. This is exacerbated in wide angle radar systems where there are likely to be 100 or more responses. Existing methods of interpretation reject low amplitude responses that can be from a close target of low radar cross section. This could result in a critical target not being detected. These are most likely to be responses from a bicycle or a pushchair but could be the only response from an electrical vehicle with a small number of metal components with a small radar cross section at the front of the vehicle. We present a method in which confidence estimates are used to preserve all radar responses and apply constraints to radar responses from a set of radar chirp waveforms, each from a set of radar sensors and reduce the level of ambiguity to a manageable level.