ANTENNA SYSTEM FOR ON-VEHICLE RADAR

摘要

PROBLEM TO BE SOLVED: To obtain the on-vehicle radar antenna system at a low cost with small size and thin profile in which beam is used to scan through electronic control without deteriorating system performance even when the number of variable phase shifters is reduced and only an object vehicle is detected through the beam scanning. SOLUTION: Plural delay lines are provided between each element antenna for transmission and a distribution circuit to provide a desired exciting amplitude/phase to each element antenna so that a fixed transmission beam is emitted where low side lobes are attained in grating lobe generating regions 22a, 22b of a received beam. Each variable phase shifter connected between each of plural reception sub arrays and a 2nd synthesis circuit applies electronic scanning to the reception beam. The reception power from other vehicle in existence in grating lobe generating regions 22a, 22b of the received beam is selected to be less than a minimum search enable power.