Nkhani

Monga gawo lofunikira kwambiri laukadaulo wapaintaneti wa Zinthu, ma tag a UHF RFID agwiritsidwa ntchito kwambiri pazinthu zambiri monga kugulitsa masitolo akuluakulu, katundu ndi malo osungiramo zinthu, malo osungiramo mabuku, kufufuza zinthu zachinyengo, ndi zina zotero. Pokhapokha mu 2021, padziko lonse lapansi. ndalama zotumizira ndizoposa 20 biliyoni.Pakugwiritsa ntchito, kodi chip cha UHF RFID passive tag chimadalira chiyani kuti chipereke mphamvu?

Makhalidwe amagetsi a UHF RFID passive tag

1. Mothandizidwa ndi mphamvu zopanda zingwe

Kutumiza kwamagetsi opanda zingwe kumagwiritsa ntchito ma radiation a electromagnetic opanda zingwe kusamutsa mphamvu zamagetsi kuchokera kumalo amodzi kupita kwina.Njira yogwirira ntchito ndikusinthira mphamvu yamagetsi kukhala mphamvu yama frequency a wailesi kudzera pa radio frequency oscillation, ndipo mphamvu ya ma radio frequency oscillation imasinthidwa kukhala mphamvu zamagetsi zamagetsi kudzera mu mlongoti wotumizira.Mphamvu yamagetsi yamagetsi yawayilesi imafalikira mlengalenga ndikufikira pa mlongoti wolandila, kenako imasinthidwa kukhala mphamvu ya ma radio frequency ndi antenna yolandila, ndipo mawonekedwe ozindikira amakhala mphamvu ya DC.

Mu 1896, Guglielmo Marchese Marconi wa ku Italy adapanga wailesi, yomwe idazindikira kufalikira kwa ma wayilesi kudutsa mlengalenga.Mu 1899, American Nikola Tesla adapereka lingaliro logwiritsa ntchito magetsi opanda zingwe, ndikukhazikitsa mlongoti womwe ndi 60m-mmwamba, inductance yodzazidwa mu botton, capacitance yodzaza pamwamba ku Colorado, pogwiritsa ntchito mafupipafupi a 150kHz kuti alowetse 300kW ya mphamvu.Imadutsa mtunda wa 42km, ndipo imapeza 10kW yamagetsi olandila opanda zingwe pamapeto olandila.

UHF RFID passive tag magetsi amatsatira lingaliro ili, ndipo owerenga amapereka mphamvu ku tag kudzera pawayilesi pafupipafupi.Komabe, pali kusiyana kwakukulu pakati pa magetsi a UHF RFID passive tag magetsi ndi mayeso a Tesla: ma frequency ndi pafupifupi kuwirikiza masauzande ambiri, ndipo kukula kwa tinyanga kumachepetsedwa nthawi chikwi.Popeza kutayika kwa ma waya opanda zingwe kumakhala kofanana ndi masikweya afupipafupi komanso molingana ndi sikweya ya mtunda, zikuwonekeratu kuti kuwonjezereka kwa kutaya kufalikira ndikokulira.Njira yosavuta yofalitsira opanda zingwe ndiyo kufalikira kwa danga.Kutayika kwa kufalitsa kumayenderana mosiyana ndi sikweya ya kutalika kwa kutalika kwa kutalika kwake komanso molingana ndi sikweya ya mtunda.Kutaya kwa malo aulere ndi LS=20lg(4πd/λ).Ngati gawo la mtunda d ndi m ndipo gawo la pafupipafupi f ndi MHz, ndiye LS= -27.56+20lgd+20lgf.

Dongosolo la UHF RFID limatengera njira yotumizira magetsi opanda zingwe.The passive tag ilibe mphamvu yakeyake.Imafunika kulandila mphamvu zamawayilesi omwe amaperekedwa ndi owerenga ndikukhazikitsa magetsi a DC kudzera pakukonzanso kuwirikiza kawiri, zomwe zikutanthauza kukhazikitsa magetsi a DC kudzera papampu ya Dickson.

Mtunda woyankhulirana woyenera wa mawonekedwe a mpweya wa UHF RFID umatsimikiziridwa makamaka ndi mphamvu yotumizira ya owerenga komanso kutayika koyambirira kwa danga.UHF band RFID owerenga owerenga mphamvu nthawi zambiri amakhala 33dBm.Kuchokera pamachitidwe oyambira otayika, kunyalanyaza kutayika kwina kulikonse, mphamvu ya RF yomwe imafika pa tagi kudzera pamagetsi opanda zingwe imatha kuwerengedwa.Ubale pakati pa mtunda wolumikizana wa mawonekedwe a mpweya wa UHF RFID ndi kutayika koyambira kofalitsa ndi mphamvu ya RF yomwe ikufika pa tagi ikuwonetsedwa patebulo:

Zitha kuwoneka kuchokera patebulo kuti UHF RFID kufalitsa mphamvu zopanda zingwe kumakhala ndi mawonekedwe a kutaya kwakukulu.Popeza RFID imagwirizana ndi malamulo olankhulana mtunda waufupi wa dziko, mphamvu yotumizira owerenga imakhala yochepa, kotero chizindikirocho chikhoza kupereka mphamvu zochepa.Pamene mtunda woyankhulirana ukuwonjezeka, mphamvu ya mawayilesi omwe amalandiridwa ndi tag yokhazikika imachepa malinga ndi ma frequency, ndipo mphamvu yamagetsi imachepa mofulumira.

2. Yambitsani mphamvu yamagetsi mwa kulipiritsa ndi kutulutsa ma capacitor osungira mphamvu pa-chip

(1) Malipiro a capacitor ndi kutulutsa

Ma Passive tag amagwiritsa ntchito magetsi opanda zingwe kuti apeze mphamvu, kuyisintha kukhala voliyumu ya DC, kulipiritsa ndikusunga ma pa-chip capacitor, ndiyeno kupereka mphamvu pazonyamula kudzera pakutulutsa.Chifukwa chake, njira yoperekera mphamvu zama tag ongokhala ndi njira yolipiritsa capacitor ndi kutulutsa.Njira yokhazikitsira ndi njira yolipiritsa yoyera, ndipo njira yoperekera mphamvu ndi kutulutsa ndi kuyitanitsa kowonjezera.Kulipiritsa kowonjezera kuyenera kuyambika mphamvu yakutulutsa isanafike pamagetsi ochepera a chip.

(2) Capacitor charge and discharge parameters

1) Malipiro magawo

Kutalika kwa nthawi yolipira: τC=RC×C

Mphamvu yamagetsi:

recharging current:

kumene RC ndiye chopinga cholipiritsa ndipo C ndi capacitor yosungirako mphamvu.

2) Kutulutsa magawo

Kutalika kwa nthawi yotulutsa: τD=RD×C

Mphamvu yamagetsi:

Kutulutsa panopa:

Mwachidule, RD ndiye kukana kutulutsa, ndipo C ndiye capacitor yosungirako mphamvu.

Zomwe zili pamwambazi zikuwonetsa mawonekedwe amagetsi a ma passive tag.Si gwero lamagetsi nthawi zonse kapena gwero lanthawi zonse, koma kulipiritsa ndi kutulutsa capacitor yosungira mphamvu.Pamene pa-chip mphamvu yosungirako capacitor ndi mlandu pamwamba voteji V0 ntchito chip circuit, akhoza kupereka mphamvu kwa tag.Pamene capacitor yosungirako mphamvu iyamba kupereka mphamvu, magetsi ake amagetsi amayamba kutsika.Ikagwera pansi pamagetsi ogwiritsira ntchito chip V0, capacitor yosungirako mphamvu imataya mphamvu yake ndipo chip sichingapitirize kugwira ntchito.Choncho, chizindikiro cha mawonekedwe a mpweya chiyenera kukhala ndi mphamvu zokwanira kuti muwonjezerenso tag.

Zitha kuwoneka kuti njira yoperekera mphamvu ya ma tag ongokhala ndiyoyenera kulumikizana ndi kuphulika, ndipo mphamvu zamagetsi zama tag opanda pake zimafunikiranso kuthandizira kuyitanitsa mosalekeza.

3 Kulinganiza kwa kapezedwe ndi kufunikira

Magetsi oyandama opangira magetsi ndi njira ina yoperekera mphamvu, ndipo mphamvu yoyandama yopangira magetsi imasinthidwa kuti igwirizane ndi kutulutsa.Koma onse ali ndi vuto wamba, ndiye kuti, magetsi a UHF RFID passive tag amayenera kulinganiza kupezeka ndi kufunikira.

(1) Kupereka ndi kufunikira kwamagetsi oyendera magetsi kuti athe kulumikizana

Muyezo wapano wa ISO/IEC18000-6 wa UHF RFID passive tag ndi wa njira yolumikizirana yophulika.Kwa ma tag opanda pake, palibe chizindikiro chomwe chimaperekedwa panthawi yolandira.Ngakhale nthawi yoyankhira imalandira mafunde onyamula, ndizofanana ndi kupeza gwero la oscillation, kotero itha kuwonedwa ngati ntchito yosavuta.Njira.Pogwiritsa ntchito izi, ngati nthawi yolandirayo ikugwiritsidwa ntchito ngati nthawi yolipiritsa ya capacitor yosungirako mphamvu, ndipo nthawi yoyankhira ndi nthawi yotulutsa capacitor yosungirako mphamvu, kuchuluka kwa ndalama zomwe zimagwiritsidwa ntchito ndi kutulutsidwa kuti zisungidwe bwino ndi zofunikira zimakhala. chikhalidwe chofunikira kusunga ntchito yachibadwa ya dongosolo.Zitha kudziwika kuchokera pamakina amagetsi azomwe zatchulidwa pamwambapa za UHF RFID kuti magetsi a UHF RFID passive tag sizomwe zimachitika nthawi zonse kapena gwero lamagetsi nthawi zonse.Pamene chizindikiro cha capacitor yosungiramo mphamvu chimaperekedwa kumagetsi apamwamba kuposa momwe amachitira voteji ya dera, magetsi amayamba;pamene tag mphamvu yosungirako capacitor imatulutsidwa ku voteji yotsika kuposa mphamvu yamagetsi yoyendetsera dera, magetsi amayimitsidwa.

Pakulankhulana kophulika, monga mawonekedwe a mpweya wa UHF RFID, chiwongolerocho chitha kulipitsidwa chisadatumize kuyankha, kokwanira kuwonetsetsa kuti magetsi okwanira atha kusungidwa mpaka yankho litatha.Choncho, kuwonjezera pa mphamvu yokwanira ya mawailesi a wailesi yomwe chizindikirocho chingalandire, chip chimafunikanso kukhala ndi mphamvu yokwanira pa-chip capacitance ndi nthawi yokwanira yolipiritsa.Kugwiritsa ntchito mphamvu kwa tag ndi nthawi yoyankha ziyeneranso kusinthidwa.Chifukwa cha mtunda wapakati pa tag ndi owerenga, nthawi yoyankhira ndi yosiyana, dera la capacitor yosungirako mphamvu ndi lochepa komanso zinthu zina, zingakhale zovuta kulinganiza kagawidwe kake ndi kufunikira mu magawo a nthawi.

(2) Kuyandama kwamagetsi opangira mphamvu zolumikizirana mosalekeza

Kwa kulankhulana kosalekeza, kuti mukhalebe ndi mphamvu yosasunthika ya capacitor yosungirako mphamvu, iyenera kutulutsidwa ndi kulipiritsa nthawi yomweyo, ndipo kuthamanga kwachangu kuli kofanana ndi kuthamanga kwachangu, ndiko kuti, mphamvu yamagetsi imasungidwa kale. kuyankhulana kwatha.

Passive tag code division radio frequency identification and UHF RFID passive tag panopa ISO/IEC18000-6 ali ndi makhalidwe ofanana.Dziko lolandira ma tag liyenera kusinthidwa ndikusinthidwa, ndipo momwe yankho liyenera kusinthidwa ndikutumizidwa.Choncho, ziyenera kupangidwa molingana ndi kulankhulana kosalekeza.Tag chip power supply system.Kuti mtengo wolipiritsa ukhale wofanana ndi wotulutsa, mphamvu zambiri zomwe zimalandiridwa ndi tag ziyenera kugwiritsidwa ntchito pakulipiritsa.

Zothandizira za RF zogawana

1. Kumapeto kwa RF kwa ma tag opanda pake

Ma tag otsika samangogwiritsidwa ntchito ngati gwero lamphamvu la ma tag ndi ma positi ku mphamvu yama frequency a wailesi kuchokera kwa owerenga, koma koposa zonse, kutumiza kwazizindikiro za malangizo kuchokera kwa owerenga kupita ku tag komanso kutumiza kwa chizindikiro kuchokera pa tag kupita kwa owerenga. anazindikira kudzera opanda zingwe deta kufala.Mphamvu zamagetsi zomwe zimalandiridwa ndi tag ziyenera kugawidwa m'magawo atatu, omwe amagwiritsidwa ntchito kuti chip chikhazikitse magetsi, kutsitsa chizindikiro (kuphatikiza chizindikiro cholamula ndi wotchi yolumikizira) ndikupereka chonyamulira.

Njira yogwirira ntchito ya UHF RFID yomwe ilipo tsopano ili ndi izi: njira yochepetsera imatengera njira yowulutsira, ndipo njira ya uplink imatenga njira yogawana ma tag angapo panjira imodzi.Chifukwa chake, potengera kufalitsa chidziwitso, ndi njira ya simplex yogwirira ntchito.Komabe, popeza chizindikirocho sichingapereke chonyamulira chotumizira, yankho la tag liyenera kupereka chonyamuliracho mothandizidwa ndi owerenga.Chifukwa chake, chizindikirocho chikayankha, malinga ndi momwe dziko likutumizira, malekezero onse a kulumikizana ali mu duplex yogwira ntchito.

M'madera osiyanasiyana ogwira ntchito, zigawo zomwe zimagwiritsidwa ntchito ndi tag zimakhala zosiyana, ndipo mphamvu zomwe zimafunika kuti magawo osiyanasiyana azigwira ntchito ndizosiyana.Mphamvu zonse zimachokera ku mphamvu ya ma radio frequency olandilidwa ndi tag.Chifukwa chake, ndikofunikira kuwongolera kugawa kwamagetsi a RF moyenera komanso ngati kuli koyenera.

2. Kugwiritsa ntchito mphamvu za RF m'maola osiyanasiyana ogwira ntchito

Chizindikirocho chikalowa m'gawo la RF ya owerenga ndikuyamba kupanga mphamvu, ziribe kanthu kuti owerenga atumiza chizindikiro chotani panthawiyi, chizindikirocho chidzapereka mphamvu zonse za RF zomwe zalandilidwa ku dera lamagetsi lowirikiza kawiri kuti lipereke capacitor yosungirako mphamvu ya pa-chip. , potero kukhazikitsa magetsi a chip.

Pamene wowerenga akutumiza chizindikiro cha lamulo, chizindikiro chotumizira owerenga ndi chizindikiro cholembedwa ndi deta ya lamulo ndi matalikidwe osinthidwa ndi kufalikira kwa ma spectrum.Pali zigawo zonyamulira ndi zida zam'mbali zomwe zimayimira data yalamulo ndikutsatizana kwa sipekitiramu mu siginecha yomwe idalandilidwa ndi tag.Mphamvu zonse, mphamvu zonyamulira, ndi zigawo zam'mbali za sigino yolandilidwa zimagwirizana ndi kusinthasintha.Panthawiyi, chigawo chosinthika chimagwiritsidwa ntchito kufalitsa chidziwitso cha kalumikizidwe cha lamulo ndi kutsatizana kwa kufalikira, ndipo mphamvu zonse zimagwiritsidwa ntchito kulipira pa-chip-power storage capacitor, yomwe nthawi yomweyo imayamba kupereka mphamvu ku-chip. synchronization m'zigawo dera ndi lamulo chizindikiro demodulation dera unit.Chifukwa chake, panthawi yomwe owerenga amatumiza malangizo, mphamvu yamagetsi yawayilesi yomwe imalandilidwa ndi tag imagwiritsidwa ntchito kuti tag ipitilize kuyitanitsa, kuchotsa chizindikiro cholumikizira, kutsitsa ndikuzindikira chizindikirocho.The tag energy storage capacitor ili mu mphamvu yoyandama yamagetsi.

Pamene opatsidwa amayankha owerenga, ndi opatsirana chizindikiro owerenga ndi chizindikiro kuti modulated ndi matalikidwe a sipekitiramu kufalitsa sipekitiramu Chip mlingo gawo laling'ono wotchi.Pachizindikiro cholandilidwa ndi tag, pali zida zonyamulira ndi zida zam'mbali zomwe zimayimira wotchi yakufalikira kwa chip.Pakadali pano, gawo losinthira limagwiritsidwa ntchito kufalitsa kuchuluka kwa chip ndi kuchuluka kwa mawotchi otsatizana, ndipo mphamvu yonse imagwiritsidwa ntchito kulipiritsa capacitor yosungira mphamvu ya pa-chip ndikusinthira zomwe zidalandilidwa ndikutumiza yankho ku wowerenga.The Chip synchronization m'zigawo dera ndi poyankha siginecha modulation dera gawo mphamvu kupereka.Choncho, panthawi yomwe owerenga amalandira yankho, chizindikirocho chimalandira mphamvu zamagetsi zamagetsi ndipo chimagwiritsidwa ntchito kuti chizindikirocho chipitirire kulipira, chizindikiro cha chip synchronization chimachotsedwa ndipo deta yoyankhidwa imasinthidwa ndipo yankho limatumizidwa.The tag energy storage capacitor ili mu mphamvu yoyandama yamagetsi.

Mwachidule, kuwonjezera pa tag yomwe imalowa mu gawo la RF ya owerenga ndikuyamba kukhazikitsa nthawi yoperekera magetsi, chizindikirocho chidzapereka mphamvu zonse za RF zomwe zalandilidwa ku dera lamagetsi lowirikiza kawiri kuti azilipiritsa capacitor yosungirako mphamvu pa-chip, potero kukhazikitsa. chip magetsi.Pambuyo pake, tagyo imachotsa kulumikizana kuchokera ku siginecha yolandila yawayilesi, imagwiritsa ntchito kutsitsa, kapena kusinthira ndikutumiza deta yoyankhira, zonse zomwe zimagwiritsa ntchito mphamvu yama frequency olandila.

3. Zofunikira zamagetsi za RF pazogwiritsa ntchito zosiyanasiyana

(1) RF mphamvu zofunika kufala opanda zingwe mphamvu

Kutengerapo kwamagetsi opanda zingwe kumakhazikitsa magetsi a tag, chifukwa chake pamafunika magetsi okwanira kuti ayendetse dera la chip, ndi mphamvu zokwanira komanso kuthekera kopitilira magetsi.

Mphamvu yotumizira magetsi opanda zingwe ndikukhazikitsa magetsi polandila mphamvu ya RF ya owerenga ndi kukonzanso kuwirikiza kawiri pomwe tag ilibe magetsi.Chifukwa chake, kukhudzika kwake kumachepetsedwa ndi kutsika kwamagetsi kwa chubu cha diode yozindikira kutsogolo.Kwa tchipisi ta CMOS, kukhudzika kolandira kwa kuwirikiza kawiri kukonzanso mphamvu kuli Pakati pa -11 ndi -0.7dBm, ndiye kutsekeka kwa ma tag osagwira ntchito.

(2) Zofunikira za mphamvu za RF kuti zizindikiridwe zazizindikiro

Pomwe kuwongolera kowirikiza kawiri kumakhazikitsa magetsi a chip, tag ikuyenera kugawa gawo la mphamvu zolandilidwa zawayilesi kuti ipereke mawonekedwe ozindikira ma siginecha, kuphatikiza kuzindikira kwa chizindikiro ndi kuzindikira kofanana ndi wotchi.Chifukwa kudziwika kwa siginecha kumachitika pansi pa chikhalidwe chakuti mphamvu ya tag yakhazikitsidwa, kukhudzidwa kwa demodulation sikumangokhala ndi kutsika kwa voliyumu ya chubu ya diode yozindikira kutsogolo, chifukwa chake kumvera kumakhala kokwera kwambiri kuposa mphamvu yopanda zingwe. kufala kulandira tilinazo, ndipo ndi ya chizindikiro matalikidwe kuzindikira, ndipo palibe mphamvu mphamvu chofunika.

(3) Zofunikira za mphamvu za RF pakuyankhidwa kwa tag

Chizindikirocho chikayankha kutumiza, kuwonjezera pa kuzindikira wotchi yolumikizana, imayeneranso kusinthira pseudo-PSK pa chonyamulira cholandila (chokhala ndi envulopu yosinthira wotchi) ndikuzindikira kutengeranso.Panthawiyi, mlingo wina wa mphamvu umafunika, ndipo mtengo wake umadalira mtunda wa owerenga ku tag ndi chidwi cha owerenga kulandira.Popeza malo ogwirira ntchito owerenga amalola kugwiritsa ntchito mapangidwe ovuta kwambiri, wolandirayo amatha kugwiritsa ntchito phokoso lakutsogolo lakumbuyo, ndipo chizindikiritso cha ma frequency radio division chimagwiritsa ntchito kufalikira kwa ma spectrum modulation, komanso kufalikira kwa spectrum ndi kupindula kwa dongosolo la PSK. , chidwi cha owerenga chingapangidwe kuti chikhale chokwanira.Kotero kuti zofunikira za chizindikiro chobwerera kwa chizindikirocho zichepetsedwa mokwanira.

Mwachidule, mphamvu ya ma frequency a wailesi yomwe imalandiridwa ndi tag imaperekedwa makamaka ngati mphamvu yamagetsi yamagetsi yopanda zingwe yowongoleredwa, ndiyeno kuchuluka koyenera kwa siginecha yozindikira chizindikiro ndi kuchuluka koyenera kwa mphamvu yosinthira kubweza kumaperekedwa kuti akwaniritse mphamvu zokwanira. kugawa ndikuwonetsetsa kulipira kosalekeza kwa capacitor yosungirako mphamvu.ndi zotheka ndi wololera mamangidwe.

Zitha kuwoneka kuti mphamvu zamagetsi zomwe zimalandilidwa ndi ma tag okhazikika zimakhala ndi zofunikira zosiyanasiyana zogwiritsira ntchito, chifukwa chake mawayilesi ogawa mphamvu amafunikira;Zofunikira pakugwiritsa ntchito mphamvu yamagetsi pawayilesi munthawi zosiyanasiyana zogwirira ntchito ndizosiyana, chifukwa chake ndikofunikira kukhala ndi kapangidwe kamagetsi kamagetsi ka wailesi molingana ndi zosowa zanthawi zosiyanasiyana zogwirira ntchito;Mapulogalamu osiyanasiyana ali ndi zofunikira zosiyanasiyana pamagetsi a RF, omwe kufalitsa magetsi opanda zingwe kumafuna mphamvu zambiri, kotero kugawira mphamvu kwa RF kuyenera kuyang'ana pa zosowa za magetsi opanda zingwe.

Ma tag a UHF RFID passive tag amagwiritsa ntchito kufalitsa magetsi opanda zingwe kuti akhazikitse magetsi.Choncho, mphamvu zamagetsi ndizochepa kwambiri ndipo mphamvu zopangira magetsi ndizochepa kwambiri.Chip tag iyenera kupangidwa ndikugwiritsa ntchito mphamvu zochepa.Dera la chip limayendetsedwa ndi kulipiritsa ndi kutulutsa capacitor yosungira mphamvu pa-chip.Choncho, pofuna kuonetsetsa kuti cholemberacho chikugwira ntchito mosalekeza, capacitor yosungirako mphamvu iyenera kulipidwa mosalekeza.Mphamvu yamagetsi yawayilesi yomwe idalandilidwa ndi tag ili ndi ntchito zitatu zosiyanasiyana: kuwongolera kuwirikiza kawiri kwa magetsi, kulandila ma siginecha ndi kutsitsa, ndikusintha ma siginecha ndi kufalitsa.Pakati pawo, kukhudzika kolandirira kwa kukonzanso kuwirikiza kawiri kumakhala koletsedwa ndi kutsika kwamagetsi a rectifier diode, yomwe imakhala mawonekedwe amlengalenga.vuto.Pazifukwa izi, kulandila kwa ma siginecha ndi kutsitsa ndikusintha ma siginolo kuyankha ndi kufalitsa ndi ntchito zofunika zomwe dongosolo la RFID liyenera kuwonetsetsa.Mphamvu yamagetsi yamphamvu ya tagi yamagetsi owirikiza kawiri, m'pamenenso chinthucho chimakhala chopikisana.Chifukwa chake, mulingo wogawira bwino mphamvu ya RF yolandirira pamapangidwe a tag system ndikuwonjezera mphamvu ya RF ndi kukonzanso kwamagetsi kawiri momwe mungathere powonetsetsa kutsika kwa siginecha yomwe idalandilidwa ndikutumiza kwa mayankho. chizindikiro.