| 摘要 |
<p>PURPOSE:To provide a function changing a radio wave reflection rate and an antenna function receiving an incoming wave by providing a microstrip antenna as a reflectrance variable element and a means using a diode to switch a feeding point of the said antenna. CONSTITUTION:The microstrip antenna 15 has a function as a reception antenna and the radar cross section area changes depending on the size of a ground plate 18 when its radiating disc 17 is in the resonance state. When the feeding point 19 is short-circuited, the radar cross section area is maximized and this value is nearly equal to the metallic plate of the same size or over. Thus, the radar cross section area, that is, the radio wave reflectance is changed largely by applying matching termination or short-circuit to the feeding point 19 of the microstrip antenna 15. The diode 20 connected to the feeding point 19 applies high frequency switching in response to on/off of a bias voltage EB applied to the diode so as to apply matching termination/short-circuit of feeding point.</p> |
