Nrog rau qhov muaj koob meej ntawm cov khoom siv wireless, cov kev pabcuam cov ntaub ntawv tau nkag mus rau lub sijhawm tshiab ntawm kev loj hlob sai, tseem hu ua kev loj hlob ntawm cov ntaub ntawv kev pabcuam. Tam sim no, ntau daim ntawv thov tau maj mam tsiv los ntawm cov khoos phis tawj mus rau cov khoom siv wireless xws li cov xov tooj ntawm tes uas yooj yim nqa thiab ua haujlwm hauv lub sijhawm, tab sis qhov xwm txheej no kuj tau ua rau muaj kev nce nrawm ntawm cov ntaub ntawv thiab kev tsis txaus ntawm cov peev txheej bandwidth. . Raws li kev txheeb cais, cov ntaub ntawv tus nqi ntawm lub khw yuav ncav cuag Gbps lossis txawm tias Tbps hauv 10 txog 15 xyoo tom ntej. Tam sim no, THz kev sib txuas lus tau mus txog Gbps cov ntaub ntawv tus nqi, thaum Tbps cov ntaub ntawv tus nqi tseem nyob rau theem pib ntawm kev txhim kho. Ib daim ntawv muaj feem tau teev cov kev nce qib tshiab hauv Gbps cov ntaub ntawv tus nqi raws li THz band thiab kwv yees tias Tbps tuaj yeem tau txais los ntawm polarization multiplexing. Yog li ntawd, txhawm rau ua kom cov ntaub ntawv sib kis tau ntau dua, kev daws teeb meem yog los tsim cov kab hluav taws xob tshiab, uas yog terahertz band, uas yog nyob rau hauv "qhov chaw dawb paug" ntawm microwaves thiab lub teeb infrared. Ntawm ITU World Radiocommunication Conference (WRC-19) xyoo 2019, qhov ntau zaus ntawm 275-450GHz tau siv rau cov kev pabcuam ruaj khov thiab hauv av. Nws tuaj yeem pom tias terahertz wireless kev sib txuas lus tau nyiam cov neeg tshawb fawb ntau.
Terahertz electromagnetic nthwv dej feem ntau txhais tau tias yog qhov zaus ntawm 0.1-10THz (1THz = 1012Hz) nrog lub wavelength ntawm 0.03-3 hli. Raws li IEEE tus qauv, terahertz nthwv dej txhais tau tias yog 0.3-10THz. Daim duab 1 qhia tau hais tias terahertz zaus band nyob nruab nrab ntawm microwaves thiab infrared teeb.
Daim duab 1 Schematic daim duab ntawm THz zaus band.
Kev txhim kho ntawm Terahertz Antennas
Txawm hais tias kev tshawb fawb terahertz pib nyob rau xyoo pua 19th, nws tsis tau kawm raws li kev ywj pheej nyob rau lub sijhawm ntawd. Kev tshawb fawb ntawm terahertz hluav taws xob feem ntau yog tsom rau ntawm qhov deb-infrared band. Nws tsis yog txog thaum nruab nrab mus txog rau xyoo pua 20th uas cov kws tshawb fawb tau pib ua qhov kev tshawb fawb millimeter yoj mus rau terahertz band thiab ua kev tshawb fawb tshwj xeeb terahertz technology.
Nyob rau xyoo 1980, qhov tshwm sim ntawm terahertz hluav taws xob qhov chaw ua rau daim ntawv thov ntawm terahertz nthwv dej hauv cov tshuab ua tau zoo. Txij li thaum xyoo pua 21st, wireless kev sib txuas lus thev naus laus zis tau tsim kho sai, thiab tib neeg qhov kev thov rau cov ntaub ntawv thiab kev nce hauv cov khoom siv sib txuas lus tau muab cov kev cai nruj dua rau kev sib kis ntawm cov ntaub ntawv sib txuas lus. Yog li ntawd, ib qho kev sib tw ntawm kev sib txuas lus thev naus laus zis yav tom ntej yog ua haujlwm ntawm cov ntaub ntawv siab ntawm gigabits ib ob hauv ib qhov chaw. Raws li kev txhim kho kev lag luam tam sim no, cov peev txheej spectrum tau dhau los ua tsawg zuj zus. Txawm li cas los xij, tib neeg txoj cai rau kev sib txuas lus muaj peev xwm thiab ceev yog qhov kawg. Rau qhov teeb meem ntawm spectrum congestion, ntau lub tuam txhab siv ntau qhov kev tawm tswv yim ntau-tso tawm (MIMO) thev naus laus zis los txhim kho spectrum efficiency thiab lub peev xwm los ntawm spatial multiplexing. Nrog rau kev nce qib ntawm 5G tes hauj lwm, cov ntaub ntawv sib txuas ceev ntawm txhua tus neeg siv yuav dhau Gbps, thiab cov ntaub ntawv kev khiav tsheb ntawm cov chaw nres tsheb hauv paus tseem yuav nce ntxiv. Rau ib txwm millimeter yoj kev sib txuas lus tshuab, microwave txuas yuav tsis muaj peev xwm tswj tau cov ntaub ntawv loj loj no. Tsis tas li ntawd, vim muaj kev cuam tshuam ntawm txoj kab ntawm qhov pom, qhov kev sib kis ntawm kev sib txuas lus infrared yog luv luv thiab qhov chaw ntawm nws cov khoom siv kev sib txuas lus yog tsau. Yog li ntawd, THz nthwv dej, uas nyob nruab nrab ntawm microwaves thiab infrared, tuaj yeem siv los tsim kev sib txuas lus ceev ceev thiab nce cov ntaub ntawv xa mus los ntawm kev siv THz txuas.
Terahertz nthwv dej tuaj yeem muab kev sib txuas lus dav dua, thiab nws qhov ntau zaus yog li 1000 npaug ntawm kev sib txuas lus ntawm tes. Yog li ntawd, siv THz los tsim ultra-high-speed wireless kev sib txuas lus yog ib qho kev cog lus rau kev sib tw ntawm cov ntaub ntawv siab, uas tau nyiam cov kev txaus siab ntawm ntau pab pawg tshawb fawb thiab kev lag luam. Thaum lub Cuaj Hlis 2017, thawj THz wireless kev sib txuas lus tus qauv IEEE 802.15.3d-2017 raug tso tawm, uas txhais tau hais tias cov ntaub ntawv sib pauv hloov pauv hauv qhov qis THz zaus ntawm 252-325 GHz. Lwm txheej txheej lub cev (PHY) ntawm qhov txuas tuaj yeem ua tiav cov ntaub ntawv txog li 100 Gbps ntawm qhov sib txawv bandwidths.
Thawj qhov kev vam meej THz kev sib txuas lus ntawm 0.12 THz tau tsim nyob rau xyoo 2004, thiab THz kev sib txuas lus ntawm 0.3 THz tau pom nyob rau xyoo 2013. Table 1 teev cov kev tshawb fawb txog kev sib txuas lus ntawm terahertz hauv Nyiv los ntawm 2004 txog 2013.
Table 1 Kev tshawb fawb kev nce qib ntawm terahertz kev sib txuas lus hauv Nyiv los ntawm 2004 txog 2013
Cov qauv kav hlau txais xov ntawm kev sib txuas lus tau tsim nyob rau xyoo 2004 tau piav qhia meej los ntawm Nippon Telegraph thiab Telephone Corporation (NTT) hauv 2005. Lub kav hlau txais xov configuration tau qhia nyob rau hauv ob rooj plaub, raws li qhia hauv daim duab 2.
Daim duab 2 Schematic daim duab ntawm Nyiv lub NTT 120 GHz wireless kev sib txuas lus system
Lub kaw lus integrates photoelectric hloov dua siab tshiab thiab kav hlau txais xov thiab txais ob hom kev ua haujlwm:
1. Nyob rau hauv ib puag ncig nyob ze, lub kav hlau txais xov transmitter siv nyob rau hauv tsev muaj ib tug tib-kab cab kuj photodiode (UTC-PD) nti, ib tug planar slot kav hlau txais xov thiab silicon lens, raws li qhia nyob rau hauv daim duab 2(a).
2. Nyob rau hauv ib puag ncig sab nraum zoov ntev, txhawm rau txhim kho kev cuam tshuam ntawm kev sib kis loj thiab tsis tshua muaj siab ntawm tus ntes, lub kav hlau txais xov transmitter yuav tsum muaj kev nce siab. Lub kav hlau txais xov terahertz uas twb muaj lawm siv Gaussian optical lens nrog nce ntau dua 50 dBi. Qhov pub horn thiab dielectric lens ua ke yog qhia hauv daim duab 2(b).
Ntxiv rau kev txhim kho 0.12 THz kev sib txuas lus, NTT kuj tau tsim 0.3THz kev sib txuas lus hauv xyoo 2012. Los ntawm kev ua kom zoo dua qub, tus nqi sib kis tuaj yeem siab txog 100Gbps. Raws li tau pom los ntawm Table 1, nws tau ua rau muaj txiaj ntsig zoo rau kev txhim kho kev sib txuas lus terahertz. Txawm li cas los xij, txoj haujlwm tshawb fawb tam sim no muaj qhov tsis zoo ntawm kev ua haujlwm tsawg zaus, qhov loj me thiab tus nqi siab.
Feem ntau ntawm cov kav hlau txais xov terahertz tam sim no tau hloov kho los ntawm millimeter yoj kav hlau txais xov, thiab tsis muaj kev hloov tshiab hauv terahertz kav hlau txais xov. Yog li ntawd, txhawm rau txhim kho kev ua haujlwm ntawm terahertz kev sib txuas lus, ib txoj haujlwm tseem ceeb yog txhawm rau txhim kho terahertz kav hlau txais xov. Table 2 teev cov kev tshawb fawb txog kev sib txuas lus German TSH. Daim duab 3 (a) qhia tau hais tias tus neeg sawv cev THz wireless kev sib txuas lus sib txuas ua ke photonics thiab electronics. Daim duab 3 (b) qhia qhov chaw kuaj cua qhov chaw. Kev txiav txim siab los ntawm qhov kev tshawb fawb tam sim no hauv lub teb chaws Yelemees, nws txoj kev tshawb fawb thiab kev tsim kho kuj muaj qhov tsis zoo xws li kev ua haujlwm tsawg zaus, tus nqi siab thiab kev ua haujlwm tsawg.
Table 2 Kev tshawb fawb kev nce qib ntawm TSH kev sib txuas lus hauv lub teb chaws Yelemees
Daim duab 3 Wind tunnel test scene
CSIRO ICT Center kuj tau pib tshawb fawb txog THz sab hauv tsev wireless kev sib txuas lus. Lub chaw kawm tau kawm txog kev sib raug zoo ntawm lub xyoo thiab kev sib txuas lus ntau zaus, raws li qhia hauv daim duab 4. Raws li pom tau los ntawm daim duab 4, los ntawm 2020, kev tshawb fawb txog kev sib txuas lus wireless nyiam mus rau THz band. Qhov kev sib txuas lus siab tshaj plaws uas siv xov tooj cua spectrum nce txog kaum zaus txhua nees nkaum xyoo. Lub chaw tau pom zoo rau qhov yuav tsum tau ua rau THz kav hlau txais xov thiab tau thov cov kav hlau txais xov ib txwm muaj xws li horns thiab lo ntsiab muag rau THz kev sib txuas lus. Raws li pom hauv daim duab 5, ob lub kav hlau txais xov horn ua haujlwm ntawm 0.84THz thiab 1.7THz feem, nrog cov qauv yooj yim thiab kev ua haujlwm zoo ntawm Gaussian beam.
Daim duab 4 Kev sib raug zoo ntawm xyoo thiab zaus
RM-BDHA818-20A IB
RM-DCPHHA 105145-20
Daim duab 5 Ob hom horn antennas
Tebchaws Asmeskas tau tshawb fawb ntau yam ntawm emissions thiab nrhiav pom ntawm terahertz nthwv dej. Cov chaw tshawb fawb terahertz nto moo suav nrog Jet Propulsion Laboratory (JPL), Stanford Linear Accelerator Center (SLAC), US National Laboratory (LLNL), National Aeronautics thiab Space Administration (NASA), National Science Foundation (NSF), thiab lwm yam. Tshiab terahertz kav hlau txais xov rau terahertz daim ntaub ntawv tau tsim, xws li bowtie antennas thiab zaus beam steering kav hlau txais xov. Raws li kev txhim kho ntawm terahertz kav hlau txais xov, peb tuaj yeem tau txais peb lub tswv yim tsim qauv yooj yim rau terahertz kav hlau txais xov tam sim no, raws li pom hauv daim duab 6.
Daim duab 6 Peb lub tswv yim tsim qauv yooj yim rau terahertz kav hlau txais xov
Cov kev soj ntsuam saum toj no qhia tau hais tias txawm hais tias ntau lub teb chaws tau them nyiaj zoo rau terahertz kav hlau txais xov, nws tseem nyob rau theem pib tshawb nrhiav thiab txhim kho. Vim muaj kev nthuav tawm siab thiab kev nqus ntawm molecular, THz antennas feem ntau raug txwv los ntawm kev sib kis thiab kev pab them nqi. Qee qhov kev tshawb fawb tsom mus rau kev ua haujlwm qis dua hauv THz band. Kev tshawb fawb terahertz kav hlau txais xov tam sim no feem ntau tsom rau kev txhim kho qhov nce los ntawm kev siv dielectric lens antennas, thiab lwm yam, thiab txhim kho kev sib txuas lus los ntawm kev siv cov algorithms tsim nyog. Tsis tas li ntawd, yuav ua li cas txhawm rau txhim kho kev ua haujlwm ntawm terahertz kav hlau txais xov ntim kuj yog qhov teeb meem ceev heev.
General TSH antennas
Muaj ntau hom THz kav hlau txais xov muaj: dipole antennas nrog conical kab noj hniav, kaum reflector arrays, bowtie dipoles, dielectric lens planar antennas, photoconductive antennas rau generating THz qhov chaw hluav taws xob qhov chaw, horn antennas, THz antennas raws li graphene cov ntaub ntawv, thiab lwm yam. cov khoom siv los ua THz kav hlau txais xov, lawv tuaj yeem muab faib ua hlau antennas (tsuas yog horn antennas), dielectric antennas (lens antennas), thiab cov khoom siv tshiab antennas. Tshooj lus no ua ntej muab kev tshuaj xyuas ua ntej ntawm cov kav hlau txais xov, thiab tom qab ntawd hauv ntu tom ntej, tsib tus kav hlau txais xov THz raug qhia kom ntxaws thiab ntsuas qhov tob.
1. Hlau kav hlau txais xov
Lub kav hlau txais xov horn yog ib hom hlau kav hlau txais xov uas tsim los ua haujlwm hauv THz band. Lub kav hlau txais xov ntawm lub classic millimeter yoj receiver yog ib tug conical horn. Corrugated thiab dual-mode kav hlau txais xov muaj ntau qhov zoo, suav nrog cov qauv hluav taws xob sib txawv, qhov nce siab ntawm 20 mus rau 30 dBi thiab qis cross-polarization theem ntawm -30 dB, thiab coupling efficiency ntawm 97% mus rau 98%. Qhov muaj bandwidths ntawm ob lub kav hlau txais xov horn yog 30% -40% thiab 6% -8%, feem.
Txij li qhov zaus ntawm terahertz nthwv dej yog siab heev, qhov loj ntawm lub kav hlau txais xov horn yog me me, uas ua rau kev ua haujlwm ntawm lub horn nyuaj heev, tshwj xeeb tshaj yog nyob rau hauv kev tsim cov kav hlau txais xov arrays, thiab cov complexity ntawm kev ua technology ua rau ntau tus nqi thiab txwv ntau lawm. Vim yog qhov nyuaj ntawm kev tsim cov hauv qab ntawm lub horn complex tsim, ib tug yooj yim horn kav hlau txais xov nyob rau hauv daim ntawv ntawm ib tug conical los yog conical horn feem ntau yog siv, uas yuav txo tau tus nqi thiab cov txheej txheem complexity, thiab cov hluav taws xob kev ua tau zoo ntawm lub kav hlau txais xov tuaj yeem tswj tau. zoo.
Lwm lub kav hlau txais xov hlau yog lub kav hlau txais xov yoj yoj pyramid, uas muaj cov kav hlau txais xov yoj mus ncig ua ke ntawm 1.2 micron dielectric zaj duab xis thiab raug tshem tawm hauv kab noj hniav ntev etched ntawm silicon wafer, raws li qhia hauv daim duab 7. Lub kav hlau txais xov no yog ib qho qhib qauv uas yog tau tshaj Schottky diodes. Vim nws cov qauv yooj yim thiab kev tsim khoom tsawg, feem ntau nws tuaj yeem siv nyob rau hauv ntau zaus bands saum 0.6 THz. Txawm li cas los xij, qib sidelobe thiab cross-polarization theem ntawm tus kav hlau txais xov yog siab, tej zaum vim nws qhib qauv. Yog li ntawd, nws cov coupling efficiency yog tsawg (kwv yees li 50%).
Daim duab 7 Mus ncig teb chaws yoj pyramidal kav hlau txais xov
2. Dielectric kav hlau txais xov
Tus kav hlau txais xov dielectric yog kev sib xyaw ntawm dielectric substrate thiab lub kav hlau txais xov radiator. Los ntawm kev tsim kom zoo, tus kav hlau txais xov dielectric tuaj yeem ua tiav impedance txuam nrog lub tshuab ntes, thiab muaj qhov zoo ntawm cov txheej txheem yooj yim, kev sib koom ua ke yooj yim, thiab tus nqi qis. Nyob rau hauv xyoo tas los no, cov kws tshawb fawb tau tsim ntau qhov nqaim thiab broadband side-fire antennas uas tuaj yeem phim cov khoom siv hluav taws xob qis ntawm terahertz dielectric antennas: Npauj npaim kav hlau txais xov, ob lub U-shaped kav hlau txais xov, kav hlau txais xov ntev ntev, thiab log-periodic sinusoidal kav hlau txais xov, xws li nyob rau hauv daim duab 8. Tsis tas li ntawd, cov kav hlau txais xov geometries nyuaj tuaj yeem tsim los ntawm cov noob caj noob ces. algorithms.
Daim duab 8 Plaub hom ntawm cov kav hlau txais xov
Txawm li cas los xij, txij li cov kav hlau txais xov dielectric tau ua ke nrog lub dielectric substrate, cov nyhuv nthwv dej saum npoo yuav tshwm sim thaum qhov zaus nyhav rau THz band. Qhov teeb meem tsis zoo no yuav ua rau lub kav hlau txais xov poob ntau lub zog thaum lub sijhawm ua haujlwm thiab ua rau muaj kev txo qis hauv cov kav hlau txais xov hluav taws xob. Raws li pom nyob rau hauv daim duab 9, thaum lub kav hlau txais xov hluav taws xob lub kaum sab xis ntau dua li lub kaum sab xis txiav, nws lub zog yog nyob rau hauv dielectric substrate thiab txuas nrog lub substrate hom.
Daim duab 9 Antenna nto yoj nyhuv
Raws li lub thickness ntawm lub substrate nce, tus naj npawb ntawm high-order hom nce, thiab cov coupling ntawm lub kav hlau txais xov thiab lub substrate nce, ua rau lub zog poob. Txhawm rau ua kom tsis muaj zog ntawm cov nyhuv nthwv dej saum npoo, muaj peb txoj kev ua kom zoo:
1) Thauj lub lens rau ntawm tus kav hlau txais xov kom nce qhov nce los ntawm kev siv lub beamforming yam ntxwv ntawm electromagnetic tsis.
2) Txo cov thickness ntawm lub substrate los suppress lub tiam ntawm high-order hom ntawm electromagnetic tsis.
3) Hloov cov khoom siv dielectric substrate nrog qhov sib txawv ntawm electromagnetic band (EBG). Lub spatial filtering yam ntxwv ntawm EBG tuaj yeem txwv cov hom kev txiav txim siab.
3. Cov khoom siv tshiab kav hlau txais xov
Ntxiv rau ob lub kav hlau txais xov saum toj no, kuj tseem muaj terahertz kav hlau txais xov ua los ntawm cov khoom siv tshiab. Piv txwv li, xyoo 2006, Jin Hao et al. thov ib tug carbon nanotube dipole kav hlau txais xov. Raws li pom nyob rau hauv daim duab 10 (a), lub dipole yog ua los ntawm carbon nanotubes es tsis txhob ntawm cov ntaub ntawv hlau. Nws ua tib zoo kawm txog cov khoom siv hluav taws xob thiab kho qhov muag ntawm cov pa roj carbon nanotube dipole kav hlau txais xov thiab tham txog cov yam ntxwv dav dav ntawm finite-ntev carbon nanotube dipole kav hlau txais xov, xws li input impedance, tam sim no faib, nce, efficiency thiab tawg qauv. Daim duab 10 (b) qhia txog kev sib raug zoo ntawm cov input impedance thiab zaus ntawm cov pa roj carbon nanotube dipole kav hlau txais xov. Raws li tuaj yeem pom hauv daim duab 10(b), qhov kev xav ntawm qhov kev tawm tswv yim impedance muaj ntau lub zeros ntawm ntau zaus. Qhov no qhia tau hais tias tus kav hlau txais xov tuaj yeem ua tiav ntau lub resonances ntawm ntau zaus. Obviously, tus kav hlau txais xov carbon nanotube nthuav tawm resonance nyob rau hauv ib tug tej yam zaus (tsawg dua THz zaus), tab sis yog kiag li tsis muaj peev xwm resonate sab nraum qhov no.
Daim duab 10 (a) Carbon nanotube dipole kav hlau txais xov. (b) Input impedance-frequency nkhaus
Nyob rau hauv 2012, Samir F. Mahmoud thiab Ayed R. AlAjmi tau thov ib tug tshiab terahertz kav hlau txais xov qauv raws li carbon nanotubes, uas muaj ib pob ntawm carbon nanotubes qhwv nyob rau hauv ob dielectric txheej. Sab hauv dielectric txheej yog ib txheej dielectric ua npuas ncauj, thiab txheej dielectric txheej yog txheej txheej metamaterial. Cov qauv tshwj xeeb yog pom hauv daim duab 11. Los ntawm kev sim, cov hluav taws xob ua haujlwm ntawm lub kav hlau txais xov tau raug txhim kho zoo dua piv nrog ib lub phab ntsa carbon nanotubes.
Daim duab 11 Tshiab terahertz kav hlau txais xov raws li carbon nanotubes
Cov khoom siv tshiab terahertz kav hlau txais xov hais saum toj no feem ntau yog peb-seem. Txhawm rau txhim kho qhov bandwidth ntawm tus kav hlau txais xov thiab ua cov kav hlau txais xov zoo, cov kav hlau txais xov graphene tau txais kev saib xyuas dav. Graphene muaj cov yam ntxwv zoo dynamic nruam tswj thiab tuaj yeem tsim cov ntshav plasma los ntawm kev kho qhov tsis sib haum xeeb. Nto plasma muaj nyob rau ntawm qhov sib cuam tshuam ntawm qhov zoo dielectric tas li substrates (xws li Si, SiO2, thiab lwm yam) thiab tsis zoo dielectric qhov chaw substrates (xws li cov hlau muaj txiaj ntsig, graphene, thiab lwm yam). Muaj ntau tus "dawb electrons" nyob rau hauv conductors xws li precious hlau thiab graphene. Cov electrons dawb no tseem hu ua plasmas. Vim lub peev xwm muaj peev xwm ua tau nyob rau hauv tus neeg xyuas pib, cov plasmas no nyob hauv lub xeev ruaj khov thiab tsis cuam tshuam los ntawm lub ntiaj teb sab nraud. Thaum qhov xwm txheej electromagnetic yoj lub zog ua ke rau cov plasmas, cov plasmas yuav sib txawv ntawm lub xeev khov kho thiab vibrate. Tom qab hloov dua siab tshiab, lub electromagnetic hom tsim ib tug transverse magnetic yoj ntawm lub interface. Raws li cov lus piav qhia ntawm kev sib raug zoo ntawm cov hlau nto plasma los ntawm tus qauv Drude, cov hlau tsis tuaj yeem ua ke nrog electromagnetic nthwv dej hauv qhov chaw dawb thiab hloov lub zog. Nws yog ib qho tsim nyog yuav tsum siv lwm cov ntaub ntawv los ua kom cov plasma nthwv dej. Nto plasma nthwv dej sai sai nyob rau hauv qhov sib npaug ntawm cov hlau-substrate interface. Thaum cov hlau conductor ua nyob rau hauv cov kev taw qhia perpendicular mus rau saum npoo, ib tug nyhuv lig rau ntawm daim tawv nqaij. Pom tseeb, vim qhov me me ntawm lub kav hlau txais xov, muaj cov nyhuv ntawm daim tawv nqaij nyob rau hauv lub siab zaus band, uas ua rau cov kav hlau txais xov kev ua tau zoo poob qis thiab tsis tuaj yeem ua tau raws li cov cai ntawm terahertz kav hlau txais xov. Qhov saum npoo plasmon ntawm graphene tsis tsuas yog muaj kev sib khi ntau dua thiab qis dua, tab sis kuj txhawb nqa hluav taws xob txuas ntxiv. Tsis tas li ntawd, graphene muaj qhov ua tau zoo hauv terahertz band. Yog li ntawd, qeeb yoj propagation yog cuam tshuam nrog plasma hom ntawm terahertz zaus. Cov yam ntxwv no ua kom pom tseeb qhov ua tau ntawm graphene los hloov cov ntaub ntawv hlau hauv terahertz band.
Raws li kev coj tus cwj pwm polarization ntawm graphene nto plasmons, Daim duab 12 qhia ib hom tshiab ntawm cov kav hlau txais xov, thiab nthuav tawm cov duab ntawm kev nthuav tawm cov yam ntxwv ntawm cov plasma nthwv dej hauv graphene. Tus tsim ntawm tunable kav hlau txais xov band muab txoj hauv kev tshiab los kawm txog kev nthuav tawm cov yam ntxwv ntawm cov khoom siv tshiab terahertz kav hlau txais xov.
Daim duab 12 Tshiab strip antenna
Ntxiv rau kev tshawb nrhiav chav tsev tshiab cov khoom siv terahertz kav hlau txais xov ntsiab lus, graphene nanopatch terahertz kav hlau txais xov kuj tuaj yeem tsim los ua arrays los tsim terahertz multi-input multi-output kav hlau txais xov sib txuas lus. Cov qauv kav hlau txais xov yog qhia hauv daim duab 13. Raws li cov khoom tshwj xeeb ntawm graphene nanopatch kav hlau txais xov, cov kav hlau txais xov muaj qhov ntev ntawm micron. Tshuaj vapor deposition ncaj qha synthesizes txawv graphene dluab ntawm ib tug nyias nickel txheej thiab hloov lawv mus rau tej substrate. Los ntawm kev xaiv tus naj npawb ntawm cov khoom tsim nyog thiab hloov cov electrostatic bias voltage, cov kev taw qhia hluav taws xob tuaj yeem hloov tau zoo, ua rau lub kaw lus rov tsim dua.
Daim duab 13 Graphene nanopatch terahertz kav hlau txais xov array
Kev tshawb fawb ntawm cov ntaub ntawv tshiab yog ib qho kev taw qhia tshiab. Kev tsim kho tshiab ntawm cov ntaub ntawv yuav tsum tau tawg los ntawm cov kev txwv ntawm cov kav hlau txais xov ib txwm thiab tsim ntau yam ntawm cov kav hlau txais xov tshiab, xws li cov khoom siv rov ua dua tshiab, cov khoom siv ob sab (2D), thiab lwm yam. Txawm li cas los xij, hom kav hlau txais xov no feem ntau yog nyob ntawm kev tsim kho tshiab. cov ntaub ntawv thiab kev nce qib ntawm cov txheej txheem technology. Txawm li cas los xij, txoj kev loj hlob ntawm terahertz kav hlau txais xov yuav tsum muaj cov ntaub ntawv tshiab, cov txheej txheem ua tiav thiab cov qauv tsim tshiab kom tau raws li qhov nce siab, tus nqi qis thiab dav bandwidth xav tau ntawm terahertz antennas.
Cov hauv qab no qhia txog cov hauv paus ntsiab lus ntawm peb hom terahertz kav hlau txais xov: hlau kav hlau txais xov, dielectric antennas thiab cov khoom siv tshiab kav hlau txais xov, thiab txheeb xyuas lawv qhov sib txawv thiab qhov zoo thiab qhov tsis zoo.
1. Hlau kav hlau txais xov: Lub geometry yog qhov yooj yim, yooj yim rau txheej txheem, kuj tsis tshua muaj nqi, thiab tsis tshua muaj kev xav tau rau cov khoom siv substrate. Txawm li cas los xij, cov kav hlau txais xov hlau siv cov cuab yeej siv los kho qhov chaw ntawm lub kav hlau txais xov, uas yog qhov ua rau yuam kev. Yog tias qhov kev hloov kho tsis raug, kev ua haujlwm ntawm lub kav hlau txais xov yuav raug txo kom tsawg. Txawm hais tias cov kav hlau txais xov hlau yog qhov me me, nws yog qhov nyuaj rau kev sib sau ua ke nrog lub phiaj xwm phiaj xwm.
2. Dielectric kav hlau txais xov: Lub dielectric kav hlau txais xov muaj qhov tsis tshua muaj input impedance, yog ib qho yooj yim kom phim nrog lub ntsuas impedance tsis tshua muaj, thiab nws kuj yooj yim rau kev sib txuas nrog lub phiaj xwm phiaj xwm. Cov duab geometric ntawm dielectric kav hlau txais xov muaj xws li npauj npaim zoo, ob npaug U duab, cov duab logarithmic zoo thiab logarithmic periodic sine puab. Txawm li cas los xij, cov kav hlau txais xov dielectric kuj muaj qhov tsis txaus ntseeg, uas yog lub ntsej muag nthwv dej tshwm sim los ntawm cov txheej txheem tuab. Txoj kev daws teeb meem yog thauj lub lens thiab hloov lub dielectric substrate nrog EBG qauv. Ob qho kev daws teeb meem xav tau kev tsim kho tshiab thiab kev txhim kho txuas ntxiv ntawm cov txheej txheem thev naus laus zis thiab cov khoom siv, tab sis lawv cov kev ua tau zoo (xws li omnidirectionality thiab nto yoj yoj) tuaj yeem muab cov tswv yim tshiab rau kev tshawb fawb ntawm terahertz antennas.
3. Cov khoom siv tshiab kav hlau txais xov: Tam sim no, cov kav hlau txais xov dipole tshiab ua los ntawm cov pa roj carbon nanotubes thiab cov kav hlau txais xov tshiab tsim los ntawm cov khoom siv metamaterials tau tshwm sim. Cov ntaub ntawv tshiab tuaj yeem coj cov kev ua tau zoo tshiab, tab sis lub hauv paus yog kev tsim kho tshiab ntawm cov ntaub ntawv science. Tam sim no, kev tshawb fawb ntawm cov khoom siv tshiab kav hlau txais xov tseem nyob rau theem tshawb nrhiav, thiab ntau cov thev naus laus zis tseem ceeb tsis paub tab txaus.
Hauv cov ntsiab lus, ntau hom terahertz kav hlau txais xov tuaj yeem xaiv raws li kev tsim qauv:
1) Yog tias tus qauv tsim yooj yim thiab cov nqi tsim khoom tsawg yuav tsum tau, cov kav hlau txais xov hlau tuaj yeem xaiv tau.
2) Yog tias muaj kev sib koom ua ke siab thiab tsis tshua muaj kev tawm tswv yim impedance, cov kav hlau txais xov dielectric tuaj yeem xaiv.
3) Yog tias yuav tsum muaj kev ua tau zoo, cov khoom siv tshiab tuaj yeem xaiv cov kav hlau txais xov.
Cov qauv tsim saum toj no kuj tuaj yeem hloov kho raws li cov kev xav tau tshwj xeeb. Piv txwv li, ob hom kav hlau txais xov tuaj yeem ua ke kom tau txais txiaj ntsig ntau dua, tab sis txoj kev sib dhos thiab tsim tshuab yuav tsum ua kom tau raws li qhov yuav tsum tau ua kom nruj dua.
Yog xav paub ntxiv txog antennas, thov mus saib:
Post lub sij hawm: Aug-02-2024
