W-band substrate integrated waveguide radar sensor based on multi-port technology

A 94 GHz collision avoidance radar sensor based on multi-port technology is proposed. This sensor makes use of substrate integrated waveguide (SIW) multi-port circuit fabricated on alumina substrate. The use of integrated waveguide allows for a full integration of the radar sensor front-ends. A specific base-band circuit generates in-phase and in-quadrature signals used to obtain the relative speed of target (including the moving direction) and the distance by elementary signal processing. Simulation and measurement results validate the operating principle of the proposed sensor and also indicate excellent results for relative velocity measurement together with good accuracy of distance measurement.