Wararka

Fogaanta akhriska iyo qorista ee aqoonsiga inta jeer ee raadiyaha (RFID) waxay kuxirantahay arrimo badan, sida awooda gudbinta akhristaha RFID, faa'iidada anteenada ee akhristaha, dareenka akhristaha IC, waxtarka guud ee anteenada akhristaha , Walxaha ku hareeraysan (gaar ahaan walxaha birta) iyo inta jeer ee raadiyaha (RF) faragelinta ka imanaya akhristayaasha RFID ee u dhow ama gudbiyaasha kale ee dibadda sida taleefannada aan xadhigga lahayn.

Waxaa ka mid ah, faa'iidada anteenadu waa arrin muhiim ah oo saameynaysa fogaanta akhriska iyo qoraalka ee akhristaha RFID.Faa'iidada anteenada waxaa loola jeedaa saamiga cufnaanta awoodda calaamadda ay dhaliso anteenada dhabta ah iyo unugga shucaaca ugu habboon ee isla goobta bannaan ee hoos yimaada xaaladda awoodda gelinta siman.Faa'iidada anteenada ayaa ah halbeeg aad u muhiim ah oo loogu talagalay tijaabinta gelitaanka shabakadda, taas oo tilmaamaysa jihaynta anteenada iyo xoogga saaridda tamarta signalada.Baaxadda faa'iidada waxay saamaysaa daboolka iyo xoogga calaamada ay gudbiso anteenadu.Sida cidhiidhiga ah ee lafaha ugu weyn iyo yar yar ee lafaha dhinaca, inta badan xoogga tamarta ayaa noqon doonta, iyo korodhka faa'iidada anteenadu waxay noqon doontaa.Guud ahaan, hagaajinta faa'iidada waxay inta badan ku xiran tahay hoos u dhigista ballaca lobe ee shucaaca jihada toosan, iyada oo la ilaalinayo waxqabadka shucaaca jiheeyaha ee diyaaradda jiifka.

Saddex qodob oo la xuso

1. Haddii aan si kale loo cayimin, faa'iidada anteenada waxaa loola jeedaa faa'iidada jihada shucaaca ugu badan;
2. Isla shuruudo la mid ah, korodhka faa'iidada, ayaa ka sii fiicnaanaya toosnaanta, iyo fogaanta fidinta mowjadaha raadiyaha, taas oo ah, masaafada kordhaysa ee la daboolay.Si kastaba ha ahaatee, ballaca xawaaraha mawjada lama cadaadin doono, iyo cidhiidhiga mawjada mawjada, ayaa ka sii dareysa labbiska daboolida.
3. Anteenadu waa aalad dadban mana kordhin doonto awoodda ishaarka.Faa'iidada anteenada waxaa badanaa la sheegaa inay la xiriirto anteeno tixraaceed gaar ah.Faa'iidada anteenada ayaa si fudud u ah awoodda si wax ku ool ah tamarta xoogga loogu saaro si ay u iftiimiso ama u hesho hirarka korantada ee jiho gaar ah.

Helitaanka Anteenada oo Gudbi Awood

Soosaarka signalka soo noqnoqda raadiyaha ee gudbiyaha raadiyaha waxaa loo soo diraa anteenada iyada oo loo sii marayo feederiyaha (cable), waxaana ku sii daaya anteenada qaab mowjado elektromagnetic ah.Kadib mowjadda korantada (electromagnetic) ay gaarto goobta laga helayo, waxaa hela anteenada (kaliya qayb yar oo ka mid ah awoodda ayaa la helay), waxaana loo diraa qaataha raadiyaha iyada oo loo marayo feederiyaha.Sidaa darteed, injineernimada shabakadda wireless, aad bay muhiim u tahay in la xisaabiyo awoodda gudbinta ee qalabka gudbinta iyo awoodda shucaaca anteenada.

Awoodda la gudbiyo ee mowjadaha raadiyaha waxaa loola jeedaa tamarta ku jirta inta jeer ee soo noqnoqda, waxaana badanaa jira laba cabbir ama halbeeg cabbir:

Awood (W)

Marka loo eego 1 Watts (Watts) heerka toosan.

Gain (dBm)

Marka loo eego heerka saamiga ee 1 milliwatt (Milliwatt).

Labada tibaax ayaa loo rogi karaa midba midka kale:

dBm = 10 x log[power mW]

mW = 10 ^ [Gain dBm / 10 dBm]

Nidaamyada bilaa-waayirka ah, anteenooyinka waxaa loo isticmaalaa in loogu beddelo mowjadaha hadda jira hirarka korantada.Inta lagu jiro habka beddelka, calaamadaha la gudbiyo iyo kuwa la helay ayaa sidoo kale "la kordhin kara".Qiyaasta kororka tamartan waxaa loo yaqaan "Gain".Faa'iidada anteenada waxaa lagu qiyaasaa "dBi".

Maaddaama tamarta hirarka elektromagnetic-ka ee nidaamka wireless-ku ay soo saarto kor-u-qaadista iyo kor-u-qaadista tamarta gudbinta ee aaladda gudbinta iyo anteenada, waxa ugu wanaagsan in lagu cabbiro tamarta gudbinta isla cabbir- faa'iido (dB), tusaale ahaan, awoodda aaladda gudbinta waa 100mW, ama 20dBm;faa'iidada anteenadu waa 10dBi, markaa:

Gudbinta tamarta guud = gudbinta awoodda (dBm) + faa'iidada anteenada (dBi)
= 20dBm + 10dBi
= 30dBm
Ama: = 1000mW = 1W

Kala dhig "taayirka", mar kasta oo calaamaduhu ay sii xoogaysteen, way sii badanayaan faa'iidada, way sii weyn tahay cabbirka anteenada, iyo cidhiidhiga xawaaraha iftiinka.
Qalabka tijaabadu waa isha ishaarada, falanqeeyaha spectrum ama qalab kale oo hela calaamada iyo hiitarka isha dhibicda.
Marka hore isticmaal anteeno shucaac isha ku habboon (qiyaastii ku habboon) si aad awood ugu kordhiso;ka dib isticmaal falanqeeye spectrum ama qalab helaya si aad u tijaabiso awooda la helay meel ka fog anteenada.Awoodda la qiyaasay waa P1;
Ku beddel anteenada tijaabada, ku dar awood isku mid ah, ku celi tijaabada kore isla boos isku mid ah, iyo awooda la qiyaasay ee la helay waa P2;
Xisaabi faa'iidada: G=10Log(P2/P1)—-Sidaan, faa'iidada anteenada ayaa lagu helaa.

Isku soo wada duuboo, waxaa la arki karaa in anteenadu tahay aalad dadban oo aan tamar dhalin karin.Faa'iidada anteenadu waa kaliya awoodda ay si wax ku ool ah u ururiso tamarta si ay u soo baxdo ama u hesho hirarka korantada ee jihada gaarka ah;faa'iidada anteenada waxaa abuura by superposition of oscillators.Mar kasta oo faa'iidada laga helo, ayaa dheeraysa dhererka anteenada.Faa'iidada waxaa lagu kordhiyaa 3dB, muggana waa labanlaab;korodhka anteenada kor u kaca, jiheynta ayaa sii wanagsan, waxaa sii dheeraya fogaanta wax akhriska, inta badan ee tamarta xooga leh, waxaa sii yaraanaya lakabyada, waxaana sii yaraanaya tirada akhriska.TheGacmo-Wireless Gacan ku haynta RFIDwaxay taageeri kartaa faa'iidada anteenada 4dbi, awoodda wax soo saarka RF waxay gaari kartaa 33dbm, masaafada wax akhrisku waxay gaari kartaa 20m, taas oo buuxin karta aqoonsiga iyo tirinta shuruudaha inta badan mashaariicda alaabada iyo bakhaarka.