1. Kev Taw Qhia
Kev siv hluav taws xob los ntawm xov tooj cua (RF) (RFEH) thiab kev hloov hluav taws xob los ntawm xov tooj cua (WPT) tau nyiam kev txaus siab heev ua cov txheej txheem los ua kom cov tes hauj lwm wireless tsis muaj roj teeb. Rectennas yog lub hauv paus ntawm WPT thiab RFEH systems thiab muaj kev cuam tshuam loj heev rau lub zog DC xa mus rau lub nra hnyav. Cov khoom siv antenna ntawm rectenna cuam tshuam ncaj qha rau kev ua haujlwm ntawm kev sau qoob loo, uas tuaj yeem hloov pauv lub zog sau los ntawm ntau qhov kev txiav txim siab ntawm qhov loj. Daim ntawv no tshuaj xyuas cov qauv tsim antenna siv hauv WPT thiab ambient RFEH daim ntawv thov. Cov rectennas tshaj tawm tau muab faib ua ob qho tseem ceeb: lub antenna rectifying impedance bandwidth thiab cov yam ntxwv ntawm lub zog ntawm lub antenna. Rau txhua qhov kev ntsuas, tus lej ntawm kev tsim nyog (FoM) rau cov ntawv thov sib txawv tau txiav txim siab thiab tshuaj xyuas sib piv.
WPT tau raug Tesla tsim tawm thaum pib ntawm lub xyoo pua 20th ua ib txoj hauv kev los xa ntau txhiab lub zog. Lo lus rectenna, uas piav qhia txog lub antenna txuas nrog lub rectifier los sau RF fais fab, tau tshwm sim hauv xyoo 1950 rau cov ntawv thov xa hluav taws xob microwave hauv qhov chaw thiab los muab hluav taws xob rau cov drones. Omnidirectional, ntev-ntau WPT raug txwv los ntawm cov khoom siv lub cev ntawm cov khoom sib kis (cua). Yog li ntawd, kev lag luam WPT feem ntau yog txwv rau kev xa hluav taws xob ze-field uas tsis yog-radiative rau kev them hluav taws xob wireless lossis RFID.
Raws li kev siv hluav taws xob ntawm cov khoom siv semiconductor thiab cov wireless sensor nodes txuas ntxiv txo qis, nws ua tau yooj yim dua rau kev siv hluav taws xob sensor nodes siv ambient RFEH lossis siv cov khoom xa tawm omnidirectional uas muaj zog tsawg. Ultra-low-power wireless fais fab systems feem ntau muaj RF acquisition pem hauv ntej, DC fais fab thiab kev tswj hwm nco, thiab lub microprocessor thiab transceiver uas muaj zog tsawg.
Daim Duab 1 qhia txog cov qauv ntawm RFEH wireless node thiab cov kev siv RF pem hauv ntej uas feem ntau tshaj tawm. Qhov ua tau zoo ntawm lub zog hluav taws xob wireless thiab cov qauv ntawm cov ntaub ntawv wireless synchronized thiab lub network hloov pauv hluav taws xob nyob ntawm kev ua tau zoo ntawm cov khoom sib txawv, xws li antennas, rectifiers, thiab cov voj voog tswj hluav taws xob. Muaj ntau cov kev tshawb fawb txog cov ntaub ntawv tau ua rau ntau qhov ntawm lub kaw lus. Rooj 1 qhia txog theem hloov pauv hluav taws xob, cov khoom tseem ceeb rau kev hloov pauv hluav taws xob zoo, thiab cov kev tshawb fawb txog cov ntaub ntawv cuam tshuam rau txhua qhov. Cov ntaub ntawv tsis ntev los no tsom mus rau kev siv tshuab hloov pauv hluav taws xob, rectifier topologies, lossis network-paub RFEH.
Daim Duab 1
Txawm li cas los xij, kev tsim qauv antenna tsis raug suav hais tias yog ib qho tseem ceeb hauv RFEH. Txawm hais tias qee cov ntaub ntawv xav txog antenna bandwidth thiab kev ua haujlwm zoo los ntawm kev xav dav dav lossis los ntawm kev xav tsim qauv antenna tshwj xeeb, xws li miniaturized lossis hnav tau antennas, qhov cuam tshuam ntawm qee qhov kev teeb tsa antenna rau kev txais hluav taws xob thiab kev hloov pauv zoo tsis tau soj ntsuam kom ntxaws.
Daim ntawv no tshuaj xyuas cov txheej txheem tsim antenna hauv rectennas nrog lub hom phiaj ntawm kev sib txawv ntawm RFEH thiab WPT cov teeb meem tsim antenna tshwj xeeb los ntawm kev tsim antenna sib txuas lus txheem. Antennas raug piv los ntawm ob lub zeem muag: qhov kawg-rau-kawg impedance matching thiab cov yam ntxwv ntawm hluav taws xob; hauv txhua kis, FoM raug txheeb xyuas thiab tshuaj xyuas hauv lub xeev-ntawm-tus-kos duab (SoA) antennas.
2. Bandwidth thiab Sib phim: Cov tes hauj lwm RF uas tsis yog 50Ω
Tus yam ntxwv impedance ntawm 50Ω yog qhov kev txiav txim siab thaum ntxov ntawm kev sib haum xeeb ntawm attenuation thiab lub zog hauv microwave engineering daim ntawv thov. Hauv antennas, qhov impedance bandwidth yog txhais tias yog qhov ntau zaus uas lub zog cuam tshuam tsawg dua 10% (S11 < − 10 dB). Txij li thaum cov amplifiers suab nrov qis (LNAs), cov amplifiers fais fab, thiab cov detectors feem ntau yog tsim nrog 50Ω input impedance match, ib qho chaw 50Ω yog ib txwm siv.
Hauv ib lub rectenna, qhov tso zis ntawm lub antenna raug pub ncaj qha rau hauv lub rectifier, thiab qhov nonlinearity ntawm lub diode ua rau muaj kev hloov pauv loj hauv qhov input impedance, nrog rau cov khoom capacitive dominating. Xav tias yog 50Ω antenna, qhov kev sib tw tseem ceeb yog tsim ib lub network sib phim RF ntxiv los hloov qhov input impedance mus rau impedance ntawm lub rectifier ntawm qhov zaus ntawm kev txaus siab thiab ua kom zoo dua rau qib fais fab tshwj xeeb. Hauv qhov no, qhov kawg-rau-kawg impedance bandwidth yog qhov yuav tsum tau ua kom ntseeg tau tias muaj kev hloov pauv RF rau DC zoo. Yog li ntawd, txawm hais tias antennas tuaj yeem ua tiav theoretically infinite lossis ultra-wide bandwidth siv cov ntsiab lus periodic lossis tus kheej-complementary geometry, qhov bandwidth ntawm rectenna yuav raug bottlenecked los ntawm lub network sib phim rectifier.
Muaj ntau lub rectenna topologies tau raug pom zoo kom ua tiav ib-band thiab ntau-band harvesting lossis WPT los ntawm kev txo qis kev cuam tshuam thiab ua kom muaj zog hloov pauv ntawm lub antenna thiab lub rectifier. Daim duab 2 qhia cov qauv ntawm cov rectenna topologies uas tau tshaj tawm, faib ua pawg los ntawm lawv cov qauv sib phim impedance. Rooj 2 qhia cov piv txwv ntawm cov rectennas ua tau zoo nrog rau qhov kawg-rau-kawg bandwidth (hauv qhov no, FoM) rau txhua pawg.
Daim Duab 2 Rectenna topologies los ntawm qhov kev xav ntawm bandwidth thiab impedance matching. (a) Ib-band rectenna nrog tus qauv antenna. (b) Multiband rectenna (muaj ntau tus antennas sib txuas ua ke) nrog ib lub rectifier thiab sib phim network ib band. (c) Broadband rectenna nrog ntau lub RF ports thiab sib phim network sib cais rau txhua band. (d) Broadband rectenna nrog broadband antenna thiab broadband matching network. (e) Ib-band rectenna siv electrically me antenna ncaj qha phim rau rectifier. (f) Ib-band, electrically loj antenna nrog complex impedance los conjugate nrog rectifier. (g) Broadband rectenna nrog complex impedance los conjugate nrog rectifier hla ntau yam frequencies.
Txawm hais tias WPT thiab ambient RFEH los ntawm kev pub tshwj xeeb yog cov ntawv thov rectenna sib txawv, kev ua tiav qhov kawg-rau-kawg sib phim ntawm antenna, rectifier thiab load yog qhov tseem ceeb kom ua tiav kev hloov pauv hluav taws xob siab (PCE) los ntawm qhov kev xav bandwidth. Txawm li cas los xij, WPT rectennas tsom mus rau kev ua tiav qhov zoo dua qhov sib phim (qis dua S11) los txhim kho ib-band PCE ntawm qee qib zog (topologies a, e thiab f). Qhov dav bandwidth ntawm ib-band WPT txhim kho lub cev tiv thaiv kab mob rau detuning, tsim khoom tsis zoo thiab ntim cov kab mob. Ntawm qhov tod tes, RFEH rectennas muab qhov tseem ceeb rau ntau-band kev ua haujlwm thiab koom nrog topologies bd thiab g, vim tias lub zog spectral density (PSD) ntawm ib-band feem ntau qis dua.
3. Tsim lub kav hlau txais xov plaub fab
1. Ib qho rectenna zaus
Tus qauv tsim ntawm lub kav hlau txais xov ntawm ib lub rectenna (topology A) feem ntau yog raws li tus qauv tsim ntawm lub kav hlau txais xov, xws li linear polarization (LP) lossis circular polarization (CP) radiating patch ntawm lub dav hlau hauv av, dipole antenna thiab inverted F antenna. Differential band rectenna yog raws li DC combination array teeb tsa nrog ntau lub antenna units lossis sib xyaw DC thiab RF ua ke ntawm ntau lub patch units.
Vim tias ntau lub antennas uas tau muab tso tawm yog cov antennas ib zaug xwb thiab ua tau raws li qhov yuav tsum tau ua ntawm WPT ib zaug xwb, thaum nrhiav RFEH ib puag ncig ntau zaus, ntau lub antennas ib zaug xwb raug muab tso ua ke rau hauv ntau txoj kab rectennas (topology B) nrog kev sib txuas ua ke thiab kev sib koom ua ke DC tom qab lub voj voog tswj fais fab kom cais lawv tawm ntawm RF tau txais thiab hloov pauv voj voog. Qhov no xav tau ntau lub voj voog tswj fais fab rau txhua txoj kab, uas yuav txo qhov ua tau zoo ntawm lub boost converter vim tias lub zog DC ntawm ib txoj kab tsawg.
2. Cov kav hlau txais xov tooj cua RFEH ntau txoj kab thiab broadband
RFEH ib puag ncig feem ntau cuam tshuam nrog kev tau txais ntau txoj kab; yog li ntawd, ntau yam txheej txheem tau raug pom zoo rau kev txhim kho qhov bandwidth ntawm cov qauv tsim antenna thiab cov txheej txheem rau kev tsim cov antenna dual-band lossis band. Hauv seem no, peb tshuaj xyuas cov qauv tsim antenna rau RFEHs, nrog rau cov antennas ntau txoj kab nrog lub peev xwm siv tau ua rectennas.
Cov kav hlau txais xov tooj cua Coplanar waveguide (CPW) monopole siv thaj chaw tsawg dua li cov kav hlau txais xov tooj cua microstrip ntawm tib lub zaus thiab tsim cov nthwv dej LP lossis CP, thiab feem ntau siv rau cov rectennas ib puag ncig broadband. Cov dav hlau reflection siv los ua kom muaj kev sib cais thiab txhim kho qhov nce, ua rau muaj cov qauv hluav taws xob zoo ib yam li cov kav hlau txais xov tooj cua. Cov kav hlau txais xov tooj cua slotted coplanar waveguide siv los txhim kho cov bandwidth impedance rau ntau qhov zaus, xws li 1.8–2.7 GHz lossis 1–3 GHz. Cov kav hlau txais xov tooj cua coupled-fed thiab cov kav hlau txais xov tooj cua patch kuj tseem siv ntau hauv cov qauv tsim rectenna ntau-band. Daim duab 3 qhia qee qhov tau tshaj tawm ntau-band antennas uas siv ntau dua ib txoj kev txhim kho bandwidth.
Daim Duab 3
Antenna-Rectifier Impedance Matching
Kev sib phim lub antenna 50Ω rau lub rectifier nonlinear yog qhov nyuaj vim tias nws cov input impedance sib txawv heev nrog zaus. Hauv topologies A thiab B (Daim Duab 2), lub network sib phim feem ntau yog LC match siv cov khoom lumped; txawm li cas los xij, qhov bandwidth sib piv feem ntau qis dua li feem ntau cov band sib txuas lus. Kev sib phim ib leeg-band stub feem ntau siv hauv microwave thiab millimeter-wave bands hauv qab 6 GHz, thiab cov millimeter-wave rectennas tshaj tawm muaj qhov bandwidth nqaim vim tias lawv cov PCE bandwidth yog bottlenecked los ntawm kev tso zis harmonic suppression, uas ua rau lawv tshwj xeeb tshaj yog rau cov ntawv thov WPT ib leeg-band hauv 24 GHz unlicensed band.
Cov rectennas hauv topologies C thiab D muaj cov tes hauj lwm sib phim nyuaj dua. Cov tes hauj lwm sib phim kab sib faib tag nrho tau raug pom zoo rau kev sib phim broadband, nrog rau RF block/DC luv luv circuit (pass filter) ntawm qhov chaw tso zis lossis DC blocking capacitor ua txoj kev rov qab rau diode harmonics. Cov khoom rectifier tuaj yeem hloov los ntawm cov ntawv luam tawm circuit board (PCB) interdigitated capacitors, uas tau synthesized siv cov cuab yeej tsim khoom siv hluav taws xob. Lwm cov tshaj tawm broadband rectenna sib phim tes hauj lwm sib xyaw ua ke cov khoom sib xyaw rau kev sib phim rau cov zaus qis dua thiab cov khoom faib tawm rau kev tsim RF luv luv ntawm qhov nkag.
Kev hloov pauv ntawm qhov nkag impedance uas pom los ntawm lub nra hnyav los ntawm qhov chaw (hu ua qhov txheej txheem rub qhov chaw) tau siv los tsim lub broadband rectifier nrog 57% bandwidth txheeb ze (1.25–2.25 GHz) thiab 10% PCE siab dua piv rau cov circuits lumped lossis distributed. Txawm hais tias cov tes hauj lwm sib phim feem ntau yog tsim los phim cov antennas hla tag nrho 50Ω bandwidth, muaj cov ntawv ceeb toom hauv cov ntaub ntawv uas cov antennas broadband tau txuas nrog cov rectifiers narrowband.
Cov tes hauj lwm sib xyaw ua ke ntawm cov khoom sib xyaw ua ke thiab cov khoom faib tawm tau siv dav hauv cov topologies C thiab D, nrog rau cov inductors thiab capacitors yog cov khoom sib xyaw ua ke uas siv ntau tshaj plaws. Cov no zam cov qauv nyuaj xws li cov capacitors interdigitated, uas xav tau kev ua qauv thiab kev tsim khoom kom raug dua li cov kab microstrip txheem.
Lub zog nkag mus rau lub rectifier cuam tshuam rau qhov impedance nkag vim yog qhov tsis sib xws ntawm lub diode. Yog li ntawd, lub rectenna yog tsim los ua kom siab tshaj plaws PCE rau qib zog nkag tshwj xeeb thiab load impedance. Txij li thaum diodes feem ntau yog capacitive siab impedance ntawm cov zaus hauv qab 3 GHz, broadband rectennas uas tshem tawm cov tes hauj lwm sib phim lossis txo qis cov voj voog sib phim yooj yim tau tsom mus rau cov zaus Prf> 0 dBm thiab siab dua 1 GHz, txij li thaum cov diodes muaj capacitive impedance qis thiab tuaj yeem phim zoo rau lub antenna, yog li zam kev tsim cov antennas nrog cov reactances nkag> 1,000Ω.
Kev sib phim impedance uas hloov tau lossis kho tau dua tshiab tau pom hauv CMOS rectennas, qhov twg lub network sib phim muaj cov capacitor banks thiab inductors hauv-chip. Cov network sib phim CMOS static kuj tau raug pom zoo rau cov antennas 50Ω tus qauv nrog rau cov antennas loop co-designed. Nws tau raug tshaj tawm tias cov khoom siv hluav taws xob CMOS passive siv los tswj cov keyboards uas coj cov zis ntawm lub antenna mus rau ntau yam rectifiers thiab cov network sib phim nyob ntawm lub zog muaj. Ib lub network sib phim uas kho tau dua tshiab siv cov capacitors lumped tunable tau raug pom zoo, uas tau kho los ntawm kev kho kom zoo thaum ntsuas qhov impedance nkag siv lub vector network analyzer. Hauv cov network sib phim microstrip uas kho tau dua tshiab, cov transistor switches tau siv los kho cov stubs sib phim kom ua tiav cov yam ntxwv dual-band.
Yog xav paub ntxiv txog antennas, thov mus saib:
Lub sijhawm tshaj tawm: Lub Yim Hli-09-2024
