An array antenna (10) includes a patch arrayed on a metal backing plate (11) and a plurality of inputs connected to the patch so as to radiate and receive an electromagnetic wave via the patch. The array antenna includes a transmitting/receiving circuit for feeding or receiving signals at a specific frequency to or from the array antenna. A waveguide (12) divided into sections is provided to feed the electromagnetic wave to the radiating antenna. Each waveguide section produces a specific phase difference along the array antenna which accumulates and causes the electromagnetic wave to focus at a particular angle. Each waveguide section therefore produces a wave focused at a different angle, allowing the antenna to generate a plurality of focused waves.
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