| 摘要 |
An antenna unit for sending out electromagnetic waves of a millimetric-wave band to outside and receiving the wave reflected from a target, and circuits for signal-processing the reflected wave are equipped as a vehicular millimetric-wave radar device. Antenna patterns are formed on a surface of a multilayer base plate formed of plural stacked layers of dielectric plates and an electroconductive layer interposed between each layer. Circuit wiring patterns and electronic components for signal processing of millimetric waves are disposed on the reverse side. Among all the above-mentioned electronic components, only a millimetric-wave signal oscillator, amplifier, and frequency converter are haused in a hermetically sealed section formed in a localized space on a face of the multilayer base plate. The other electronic components are arranged in a non-hermetically structured condition on a periphery of the hermetically sealed section. The above-mentioned oscillator, amplifier, and frequency converter are hermetically sealed in an inert gas atmosphere, whereas at least part of the other electronic components arranged in a non-hermetically structured condition is protected by resin coating. With this configuration, a compact, thin, and highly accurate millimetric-wave radar device is provided at a low cost. <IMAGE> |
