Kev Tshuaj Xyuas Antenna: Kev Tshuaj Xyuas Fractal Metasurfaces thiab Antenna Design

Lub tswv yim ntawm fractals tau qhia los ntawm tus kws lej Benoit B. Mandelbrot hauv xyoo 1970, txawm hais tias keeb kwm ntawm fractal geometry tuaj yeem taug qab mus rau cov haujlwm ua ntej ntawm ntau tus kws lej, xws li Cantor (1870), von Koch (1904), Sierpinski (1915), Julia (1918), Fatou (1926), thiab Richardson (1953).
Benoit B. Mandelbrot tau kawm txog kev sib raug zoo ntawm fractals thiab xwm los ntawm kev qhia txog cov hom fractals tshiab los ua qauv rau cov qauv nyuaj dua, xws li ntoo, roob, thiab ntug dej hiav txwv. Nws tau hais lo lus "fractal" los ntawm Latin adjective "fractus", txhais tau tias "tawg" lossis "fractured", piv txwv li muaj cov khoom tawg lossis tsis sib xws, los piav qhia txog cov duab geometric tsis sib xws thiab tawg uas tsis tuaj yeem faib los ntawm Euclidean geometry ib txwm muaj. Tsis tas li ntawd, nws tau tsim cov qauv lej thiab cov algorithms rau kev tsim thiab kawm fractals, uas ua rau muaj kev tsim cov Mandelbrot teeb tsa nto moo, uas yog qhov nto moo tshaj plaws thiab pom kev zoo nkauj fractal duab nrog cov qauv nyuaj thiab rov ua dua tsis kawg (saib Daim Duab 1d).
Mandelbrot txoj haujlwm tsis yog tsuas yog muaj kev cuam tshuam rau kev suav lej xwb, tab sis kuj muaj kev siv rau ntau yam xws li physics, computer graphics, biology, economics, thiab art. Qhov tseeb, vim lawv muaj peev xwm los ua qauv thiab sawv cev rau cov qauv nyuaj thiab zoo sib xws, fractals muaj ntau daim ntawv thov tshiab hauv ntau yam. Piv txwv li, lawv tau siv dav hauv cov chaw thov hauv qab no, uas tsuas yog ob peb qhov piv txwv ntawm lawv daim ntawv thov dav:
1. Cov duab kos hauv computer thiab cov yeeb yaj kiab, tsim cov toj roob hauv pes ntuj, ntoo, huab, thiab cov qauv zoo nkauj thiab pom tseeb;
2. Kev siv tshuab compression los txo qhov loj ntawm cov ntaub ntawv digital;
3. Kev ua cov duab thiab cov teeb liab, rho tawm cov yam ntxwv ntawm cov duab, nrhiav cov qauv, thiab muab cov txheej txheem nias thiab rov tsim cov duab zoo;
4. Kev kawm txog tsiaj txhu, piav qhia txog kev loj hlob ntawm cov nroj tsuag thiab kev teeb tsa cov neurons hauv lub hlwb;
5. Kev tshawb fawb txog Antenna thiab cov khoom siv metamaterials, tsim cov antennas compact/multi-band thiab cov metasurfaces tshiab.
Tam sim no, fractal geometry tseem niaj hnub nrhiav kev siv tshiab thiab tshiab hauv ntau yam kev tshawb fawb, kev kos duab thiab kev siv tshuab.
Hauv kev siv tshuab electromagnetic (EM), cov duab fractal muaj txiaj ntsig zoo rau cov ntawv thov uas xav tau miniaturization, los ntawm antennas mus rau metamaterials thiab zaus xaiv qhov chaw (FSS). Kev siv fractal geometry hauv cov antennas ib txwm muaj tuaj yeem ua rau lawv qhov ntev hluav taws xob nce ntxiv, yog li txo qhov loj me ntawm cov qauv resonant. Tsis tas li ntawd, qhov xwm txheej zoo sib xws ntawm cov duab fractal ua rau lawv zoo tagnrho rau kev paub txog ntau-band lossis broadband resonant qauv. Lub peev xwm miniaturization ntawm fractals yog qhov tshwj xeeb tshaj yog rau kev tsim cov reflectarrays, phased array antennas, metamaterial absorbers thiab metasurfaces rau ntau yam kev siv. Qhov tseeb, kev siv cov ntsiab lus array me me tuaj yeem coj ntau yam zoo, xws li txo kev sib koom ua ke lossis muaj peev xwm ua haujlwm nrog arrays nrog qhov sib nrug me me, yog li ua kom muaj kev ua haujlwm zoo scanning thiab qib siab dua ntawm kev ruaj khov angular.
Vim yog cov laj thawj uas tau hais los saum toj no, fractal antennas thiab metasurfaces sawv cev rau ob qhov chaw tshawb fawb zoo heev hauv kev tshawb fawb txog electromagnetics uas tau nyiam ntau qhov kev saib xyuas hauv xyoo tas los no. Ob lub tswv yim no muab cov txoj hauv kev tshwj xeeb los tswj thiab tswj cov nthwv dej electromagnetic, nrog rau ntau yam kev siv hauv kev sib txuas lus wireless, radar systems thiab sensing. Lawv cov khoom zoo sib xws tso cai rau lawv kom me me thaum tswj hwm cov lus teb electromagnetic zoo heev. Qhov compactness no yog qhov tshwj xeeb tshaj yog nyob rau hauv qhov chaw-txwv daim ntawv thov, xws li cov khoom siv mobile, RFID tags, thiab aerospace systems.
Kev siv cov fractal antennas thiab metasurfaces muaj peev xwm los txhim kho kev sib txuas lus wireless, kev thaij duab, thiab radar systems, vim lawv ua rau cov khoom siv compact, high-performance nrog kev ua haujlwm zoo dua. Tsis tas li ntawd, fractal geometry tau siv ntau dua hauv kev tsim cov microwave sensors rau kev kuaj mob khoom siv, vim nws muaj peev xwm ua haujlwm hauv ntau zaus bands thiab nws muaj peev xwm miniaturized. Kev tshawb fawb txuas ntxiv mus hauv cov cheeb tsam no txuas ntxiv tshawb nrhiav cov qauv tsim tshiab, cov ntaub ntawv, thiab cov txheej txheem tsim khoom kom paub txog lawv lub peev xwm tag nrho.
Daim ntawv no lub hom phiaj yog los tshuaj xyuas kev tshawb fawb thiab kev nce qib ntawm kev siv cov fractal antennas thiab metasurfaces thiab piv rau cov fractal-based antennas thiab metasurfaces uas twb muaj lawm, qhia txog lawv cov txiaj ntsig thiab kev txwv. Thaum kawg, kev tshuaj xyuas dav dav ntawm cov reflectarrays tshiab thiab metamaterial units tau nthuav tawm, thiab cov teeb meem thiab kev txhim kho yav tom ntej ntawm cov qauv electromagnetic no tau tham txog.