Nkhani

Mtunda wowerengera ndi kulemba wa owerenga ma radio frequency identification (RFID) amatengera zinthu zambiri, monga mphamvu yotumizira wowerenga RFID, kupindula kwa mlongoti wa owerenga, kumva kwa wowerenga IC, mphamvu ya antenna yonse ya owerenga. , Zinthu zozungulira (makamaka zinthu zachitsulo) ndi kusokoneza kwa wailesi (RF) kuchokera kwa owerenga a RFID apafupi kapena ma transmitter ena akunja monga mafoni opanda zingwe.

Pakati pawo, kupindula kwa mlongoti ndi chinthu chofunikira chomwe chikukhudza mtunda wowerenga ndi kulemba wa owerenga RFID.Kupindula kwa mlongoti kumatanthawuza chiŵerengero cha kachulukidwe ka mphamvu ya siginecha yopangidwa ndi mlongoti weniweni ndi gawo loyenera la radiation pamalo omwewo mumlengalenga pansi pa mphamvu yolowera yofanana.Kupindula kwa mlongoti ndi gawo lofunikira kwambiri pakuyezetsa mwayi wopezeka pa netiweki, zomwe zikuwonetsa kulunjika kwa mlongoti komanso kuchuluka kwa mphamvu zamawu.Kukula kwa phindu kumakhudza kuphimba ndi mphamvu ya chizindikiro chomwe chimaperekedwa ndi mlongoti.Kuchepa kwa lobe yayikulu ndi kuchepera kwa lobe yam'mbali, mphamvu yowonjezereka idzakhala yowonjezereka, ndipo phindu la antenna lidzakhala lokwera.Nthawi zambiri, kuwongolera kwa phindu kumatengera kuchepetsa kukula kwa ma radiation molunjika, ndikusunga magwiridwe antchito a omnidirectional mu ndege yopingasa.

Mfundo zitatu zofunika kuzikumbukira

1. Pokhapokha ngati tafotokozedwa mwanjira ina, kupindula kwa mlongoti kumatanthawuza kupindula mumayendedwe apamwamba a radiation;
2. Pazikhalidwe zomwezo, kupindula kwakukulu, kuwongolera bwino, komanso kutalikirana kwa kufalikira kwa mafunde a wailesi, ndiko kuti, mtunda wowonjezereka wophimbidwa.Komabe, m'lifupi mafunde liwiro si wothinikizidwa, ndi yopapatiza yoweyula lobe, kuipa yunifolomu Kuphunzira.
3. Mlongoti ndi chipangizo chokhazikika ndipo sichidzawonjezera mphamvu ya chizindikiro.Kupeza kwa mlongoti nthawi zambiri kumanenedwa kuti kumagwirizana ndi mlongoti wina.Kupindula kwa mlongoti ndikungotha ​​kuyika mphamvu moyenera kuti iwunikire kapena kulandira mafunde amagetsi mbali ina yake.

Kupeza kwa Antenna ndi Kutumiza Mphamvu

Kutulutsa kwa ma radio frequency ndi chowulutsira wailesi kumatumizidwa ku mlongoti kudzera mu feeder (chingwe), ndipo kumawunikiridwa ndi mlongoti mu mawonekedwe a mafunde amagetsi.Pambuyo pa mafunde a electromagnetic kufika kumalo olandirira, amalandiridwa ndi mlongoti (gawo laling'ono chabe la mphamvu limalandiridwa), ndipo limatumizidwa kwa wolandira wailesi kudzera mu feeder.Chifukwa chake, muukadaulo wamaukadaulo opanda zingwe, ndikofunikira kwambiri kuwerengera mphamvu yotumizira chipangizocho komanso mphamvu ya radiation ya mlongoti.

Mphamvu yopatsirana ya mafunde a wailesi imatanthawuza mphamvu yomwe ili mkati mwa mtunda woperekedwa, ndipo nthawi zambiri pamakhala miyeso iwiri kapena miyeso yoyezera:

Mphamvu (W)

Zogwirizana ndi 1 Watts (Watts) mzere wa mzere.

Kupeza (dBm)

Zogwirizana ndi mulingo wofananira wa 1 milliwatt (Milliwatt).

Mawu awiriwa akhoza kutembenuzidwa wina ndi mzake:

dBm = 10 x chipika[mphamvu mW]

mW = 10^[Pezani dBm / 10 dBm]

M'machitidwe opanda zingwe, tinyanga zimagwiritsidwa ntchito kusintha mafunde apano kukhala mafunde amagetsi.Panthawi yotembenuka, zizindikiro zomwe zimaperekedwa ndi kulandiridwa zimathanso "kukulitsa".Muyeso wa kukulitsa mphamvu uku kumatchedwa "Gain".Kupeza kwa mlongoti kumayesedwa mu "dBi".

Popeza mphamvu yamagetsi yamagetsi mumagetsi opanda zingwe imapangidwa ndi kukulitsa ndi kukulira kwa mphamvu yotumizira chipangizocho ndi mlongoti, ndi bwino kuyeza mphamvu yotumizira ndi muyeso womwewo (dB), mwachitsanzo, mphamvu ya chipangizo chotumizira ndi 100mW, kapena 20dBm;phindu la mlongoti ndi 10dBi, ndiye:

Kutumiza mphamvu zonse = mphamvu zotumizira (dBm) + phindu la mlongoti (dBi)
= 20dBm + 10dBi
= 30dBm
Kapena: = 1000mW = 1W

Gwiranitsani "tayala", pamene chizindikirocho chimayika kwambiri, kupindula kwakukulu, kukula kwa mlongoti, ndi kuchepetsa bandwidth yamtengo.
Zida zoyesera ndi gwero la ma sign, spectrum analyzer kapena zida zina zolandirira ma siginecha ndi radiator source source.
Choyamba gwiritsani ntchito mlongoti wabwino (pafupifupi) woyambira ma radiation kuti muwonjezere mphamvu;Kenako gwiritsani ntchito spectrum analyzer kapena chipangizo cholandirira kuti muyese mphamvu yomwe mwalandira pamtunda wina kuchokera ku mlongoti.Mphamvu yoyesedwa yolandila ndi P1;
Bwezerani mlongoti poyesedwa, onjezani mphamvu zomwezo, bwerezani mayesero omwe ali pamwambawa pamalo omwewo, ndipo mphamvu yomwe analandira ndi P2;
Werezerani phindu: G=10Log(P2/P1)——Mwanjira imeneyi, phindu la mlongoti limapezedwa.

Kuti tifotokoze mwachidule, zitha kuwoneka kuti mlongoti ndi chipangizo chomwe sichingathe kupanga mphamvu.Kupindula kwa mlongoti ndikuthekera kokha kuyika mphamvu zowunikira kapena kulandira mafunde amagetsi mbali ina yake;kupindula kwa mlongoti kumapangidwa ndi superposition ya oscillators.Kupindula kwapamwamba, kutalika kwa mlongoti.Kupindula kumawonjezeka ndi 3dB, ndipo voliyumu imawirikiza kawiri;kuchulukitsa kwa mlongoti, kuwongolera kwabwino, mtunda wowerengera, mphamvu yokhazikika kwambiri, ma lobes amachepera, komanso kuchepera kowerengera.TheHandheld-WIreless RFID pamanjaimatha kuthandizira kupindula kwa mlongoti wa 4dbi, mphamvu ya RF yotulutsa imatha kufika 33dbm, ndipo mtunda wowerengera ukhoza kufika 20m, womwe ungakwaniritse chizindikiritso ndi kuwerengera zofunikira zamapulojekiti ambiri osungiramo katundu ndi nyumba zosungiramo katundu.