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다음과 같은 기능을 한번의 로그인으로 사용 할 수 있습니다.
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Kafe 바로가기국가/구분 | United States(US) Patent 등록 |
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국제특허분류(IPC7판) |
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출원번호 | US-0327090 (1994-10-21) |
발명자 / 주소 |
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출원인 / 주소 |
|
인용정보 | 피인용 횟수 : 251 인용 특허 : 0 |
An antenna array for direction-agile applications, such as r.f. packet mesh networks, employs a plurality of quarter-wave radiators disposed normally to a ground plane on a dielectric backing and switching elements for selecting a desired receiving direction and transmission direction and minimizing
An antenna array for direction-agile applications, such as r.f. packet mesh networks, employs a plurality of quarter-wave radiators disposed normally to a ground plane on a dielectric backing and switching elements for selecting a desired receiving direction and transmission direction and minimizing interference from signals in opposing directions. A control system selects and switches direction rapidly enough to receive and transmit digipeating signals in selected different directions using the phasing and switching elements. A specific embodiment employs eight radiators of 0.2625 electrical wavelengths (quarter wave plus 5%) disposed equidistant along a circle within a circular ground plane in a pattern which is ¼wavelength from the outer boundary of the ground plane, each radiator being disposed at least 0.15 wavelengths to about 0.25 wavelengths from adjacent radiators in a circular pattern. The antenna is characterized by eight electronically switchable radiating directions (at 45°intervals) with at least 20 dB front to back ratio and a 3 dB beamwidth of 64°. Pairs of radiators form parasitic elements, driven elements and reflectors with spacing selected as a modest compromise from the ideal spacing to allow electronically selectable directionality using identically-spaced elements acting as driven elements, parasitic elements and reflector elements. The driven elements are slightly reactively fed.
A multiple-element array antenna system comprising: a conductive ground plane base having an outer boundary; eight equal-length radiating elements of at least one-quarter wavelength electrical length at a selected operating frequency, each said radiating element being disposed with a first end adjac
A multiple-element array antenna system comprising: a conductive ground plane base having an outer boundary; eight equal-length radiating elements of at least one-quarter wavelength electrical length at a selected operating frequency, each said radiating element being disposed with a first end adjacent said ground plane and a second end protruding normal to said ground plane, each said radiating element being arranged equidistant along on a circle within said conductive ground plane, said circle being disposed at least one quarter wavelength from said outer boundary in an equally space pattern, wherein two of said radiating elements are selectable as type 1 elements and two of said radiating elements are selectable as type 2 elements, while unused elements are effectively electrically isolated, wherein said two type 1 elements are driven elements and are spaced from one another by three element positions in one circular direction and five element positions in the opposing circular direction on said circle, wherein said two type 2 are spaced from one another by three element positions in one circular direction and five element positions in the opposing circular direction on said circle, and wherein each said driven element is spaced by one element position from one of said type 2 elements; a plurality of feed means, each said feed means being electrically coupled to corresponding element feedpoints at said first ends; and switching means for gating r.f. energy to selected ones of said feed means; said pattern of said radiating elements and said switching means governing a preselected switchable radiating pattern having a maximized front-to-back ratio.
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