I. Nhanganyaya
Zvinhu zveMetateri zvinogona kutsanangurwa zvakanakisisa sezvivakwa zvakagadzirwa nemaoko kuti zvigadzire zvimwe zvinhu zvemagetsi zvisingawanikwe zvakasikwa. Zvinhu zveMetateri zvine mvumo yekubvumidza uye kubvumidzwa kwemagetsi zvisina kunaka zvinonzi metaterials dzeruoko rweruboshwe (LHMs). LHM dzakadzidzwa zvakanyanya munharaunda dzesainzi nedzeinjiniya. Muna 2003, LHM dzakanzi ndeimwe yenzira gumi dzepamusoro dzesainzi dzenguva yemazuva ano nemagazini yeScience. Mashandisirwo matsva, pfungwa, uye zvishandiso zvakagadzirwa nekushandisa hunhu hwakasiyana hweLHMs. Nzira yekutumira mutsetse (TL) inzira inoshanda yekugadzira inogona zvakare kuongorora misimboti yeLHMs. Zvichienzaniswa neTLs dzechinyakare, chinhu chakakosha cheTLs dzemetaterial ndiko kudzora kwema TL parameters (propagation constant) uye characteristic impedance. Kudzora kwema TL parameters emetaterial kunopa mazano matsva ekugadzira antenna structures dzine saizi yakamanikana, kushanda kwepamusoro, uye mabasa matsva. Mufananidzo 1 (a), (b), uye (c) unoratidza mamodheru ecircuit asina kurasikirwa emutsetse wekutumira weruoko rwerudyi (PRH), mutsetse wekutumira weruoko rweruboshwe (PLH), uye mutsetse wekutumira weruoko rweruboshwe (CRLH), zvichiteerana. Sezvakaratidzwa muMufananidzo 1(a), muenzaniso wedunhu wakaenzana wePRH TL unowanzo kuve musanganiswa we series inductance uye shunt capacitance. Sezvakaratidzwa muMufananidzo 1(b), muenzaniso wedunhu wePLH TL musanganiswa we shunt inductance uye series capacitance. Mukushanda kwechokwadi, hazvigoneki kushandisa PLH circuit. Izvi zvinokonzerwa neparasitic series inductance uye shunt capacitance effects. Nokudaro, hunhu hwemutsara wekutumira weruoko rweruboshwe unogona kuonekwa pari zvino zvese zvimiro zveruoko rweruboshwe neruoko rwerudyi, sezvakaratidzwa muMufananidzo 1(c).
Mufananidzo 1 Mhando dzakasiyana dzemasekete emagetsi ekutumira
Chinogadzika chekuparadzira (γ) chemutsetse wekutumira (TL) chinoverengerwa seizvi: γ=α+jβ=Sqrt(ZY), apo Y naZ vanomiririra kubvumidzwa uye impedance zvakateerana. Tichifunga nezve CRLH-TL, Z naY zvinogona kuratidzwa seizvi:
CRLH TL yakafanana ichave nehukama hwekupararira hunotevera:
Chikamu chinogara chichishandiswa β chinogona kuva nhamba chaiyo kana nhamba yekufungidzira. Kana β iri chaiyo mukati mehuwandu hwema frequency, pane passband mukati mehuwandu hwema frequency nekuda kwemamiriro ezvinhu γ=jβ. Kune rumwe rutivi, kana β iri nhamba yekufungidzira mukati mehuwandu hwema frequency, pane stopband mukati mehuwandu hwema frequency nekuda kwemamiriro ezvinhu γ=α. Chinomira ichi chakasiyana neCRLH-TL uye hachipo muPRH-TL kana PLH-TL. Mifananidzo 2 (a), (b), na (c) inoratidza ma dispersion curves (kureva, hukama hwe ω - β) hwePRH-TL, PLH-TL, uye CRLH-TL, zvichiteerana. Zvichibva pama dispersion curves, group velocity (vg=∂ω/∂β) uye phase velocity (vp=ω/β) ye transmission line zvinogona kuwanikwa uye kufungidzirwa. Kune PRH-TL, zvinogonawo kufungidzirwa kubva mu curve kuti vg na vp zvakafanana (kureva, vpvg>0). Kune PLH-TL, curve inoratidza kuti vg na vp hazvisi parallel (kureva, vpvg<0). Curve yekupararira kweCRLH-TL inoratidzawo kuvapo kwenzvimbo yeLH (kureva, vpvg <0) uye nzvimbo yeRH (kureva, vpvg > 0). Sezvatinoona kubva paMufananidzo 2(c), weCRLH-TL, kana γ iri nhamba chaiyo chaiyo, pane stop band.
Mufananidzo 2 Makomba ekupararira kwemitsara yakasiyana yekutumira
Kazhinji, ma "series" uye "parallel resonances" eCRLH-TL akasiyana, ayo anonzi "unbalanced state". Zvisinei, kana ma "series" uye "parallel resonance frequencies" akafanana, anonzi "balanced state", uye muenzaniso we "simplified equivalent circuit" unoratidzwa muMufananidzo 3(a).
Mufananidzo 3. Muenzaniso wedunhu uye curve yekupararira kwemutsetse wekutumira weruoko rweruboshwe wakabatanidzwa
Sezvo frequency ichiwedzera, hunhu hwekupararira kweCRLH-TL hunowedzera zvishoma nezvishoma. Izvi zvinodaro nekuti phase velocity (kureva, vp=ω/β) inowedzera kutsamira pafrequency. Pa frequency yakaderera, CRLH-TL inotongwa neLH, nepo pa frequency yakakwira, CRLH-TL inotongwa neRH. Izvi zvinoratidza hunhu hweCRLH-TL huviri. Dhayagiramu yekupararira kweCRLH-TL ye equilibrium inoratidzwa muMufananidzo 3(b). Sezvakaratidzwa muMufananidzo 3(b), shanduko kubva kuLH kuenda kuRH inoitika pa:
Apo ω0 iri frequency yekuchinja. Saka, muchiitiko chakayerwa, shanduko yakatsetseka inoitika kubva kuLH kuenda kuRH nekuti γ inhamba yekufungidzira chete. Saka, hapana stopband yekupararira kweCRLH-TL kwakaringana. Kunyangwe β iri zero paω0 (isina muganho kana tichienzanisa newavelength yakatungamirirwa, kureva, λg=2π/|β|), wave ichiri kupararira nekuti vg paω0 haisi zero. Saizvozvowo, paω0, phase shift ndeye zero paTL yehurefu d (kureva, φ= - βd=0). Phase advance (kureva, φ>0) inoitika muLH frequency range (kureva, ω<ω0), uye phase retardation (kureva, φ<0) inoitika muRH frequency range (kureva, ω>ω0). Kune CRLH TL, characteristic impedance inotsanangurwa seinotevera:
Apo ZL neZR zviri PLH nePRH impedances, zvichiteerana. Kune iyo isina kuenzana, hunhu hweimpedance hunoenderana nefrequency. Iyo equation iri pamusoro inoratidza kuti iyo balanced case haina chekuita nefrequency, saka inogona kuva ne wide bandwidth match. Iyo TL equation yakawanikwa pamusoro yakafanana ne constitutive parameters inotsanangura CRLH material. Iyo propagation constant yeTL ndi γ=jβ=Sqrt(ZY). Tichifunga nezve propagation constant yechinhu (β=ω x Sqrt(εμ)), iyo equation inotevera inogona kuwanikwa:
Saizvozvowo, hunhu hweimpedance yeTL, kureva, Z0=Sqrt(ZY), hwakafanana nehunhu hweimpedance yezvinhu, kureva, η=Sqrt(μ/ε), iyo inoratidzwa se:
Nhamba yekurefractive index yeCRLH-TL yakaenzana uye isina kuenzana (kureva, n = cβ/ω) inoratidzwa muMufananidzo 4. MuMufananidzo 4, nhamba yekurefractive index yeCRLH-TL muhuwandu hwayo hweLH iri negative uye nhamba yekurefractive index muhuwandu hwayo hweRH iri positive.
Mufananidzo 4 Zviratidzo zve refractive indices zve CRLH TLs dzakaringana uye dzisina kuenzana.
1. Network yeLC
Nekubvisa masero eLC ebandpass anoratidzwa muMufananidzo 5(a), CRLH-TL yakajairika ine hurefu hwakafanana hwe d inogona kugadzirwa nguva nenguva kana kuti kwete nguva nenguva. Kazhinji, kuitira kuve nechokwadi chekuti kuve nyore kuverenga nekugadzira CRLH-TL, dunhu rinofanira kuva nguva nenguva. Kana tichienzanisa nemuenzaniso weMufananidzo 1(c), sero redunhu reMufananidzo 5(a) harina saizi uye hurefu hwepanyama hudiki zvikuru (kureva, Δz mumamita). Tichifunga nezvehurefu hwaro hwemagetsi θ=Δφ (rad), chikamu chesero reLC chinogona kuratidzwa. Zvisinei, kuti tinyatsoona inductance inoshandiswa uye capacitance, kureba kwemuviri p kunofanirwa kusimbiswa. Sarudzo yetekinoroji yekushandisa (senge microstrip, coplanar waveguide, zvikamu zvesurface mount, nezvimwewo) zvichakanganisa saizi yemuviri yesero reLC. Sero reLC reMufananidzo 5(a) rakafanana nemuenzaniso wekuwedzera weMufananidzo 1(c), uye muganho waro p=Δz→0. Zvichienderana nemamiriro akafanana p→0 muMufananidzo 5(b), TL inogona kugadzirwa (nekuburitsa masero eLC) yakaenzana neyunifomu yakakodzera CRLH-TL ine urefu hwe d, kuitira kuti TL iite seyakafanana nemafungu emagetsi.
Mufananidzo 5 CRLH TL yakavakirwa panetwork yeLC.
Kune sero reLC, tichifunga nezvemamiriro emiganhu yenguva (PBCs) akafanana neBloch-Floquet theorem, hukama hwekupararira kwesero reLC hunoratidzwa uye hunoratidzwa seinotevera:
Impedance yemutsara (Z) uye shunt admittance (Y) yeLC cell zvinotsanangurwa nemaequation anotevera:
Sezvo kureba kwemagetsi kwechikamu cheLC circuit kuri kudiki kwazvo, Taylor approximation inogona kushandiswa kuwana:
2. Kuitwa Kwemuviri
Muchikamu chakapfuura, network yeLC yekugadzira CRLH-TL yakakurukurwa. Network dzakadaro dzeLC dzinogona kungowanikwa chete nekushandisa zvikamu zvemuviri zvinogona kugadzira capacitance inodiwa (CR neCL) uye inductance (LR neLL). Mumakore achangopfuura, kushandiswa kwezvikamu zvechip zvesurface mount (SMT) kana zvikamu zvakagoverwa kwakakwezva kufarira kukuru. Microstrip, stripline, coplanar waveguide kana mamwe matekinoroji akafanana anogona kushandiswa kugadzira zvikamu zvakagoverwa. Pane zvinhu zvakawanda zvekufunga nezvazvo pakusarudza machipisi eSMT kana zvikamu zvakagoverwa. Maumbirwo eCRLH akavakirwa paSMT akajairika uye ari nyore kushandisa maererano nekuongorora nekugadzira. Izvi zvinokonzerwa nekuwanikwa kwezvikamu zvechip zveSMT zvisiri pasherufu, izvo zvisingade kugadziriswa uye kugadzirwa zvichienzaniswa nezvikamu zvakagoverwa. Zvisinei, kuwanikwa kwezvikamu zveSMT kwakapararira, uye zvinowanzo shanda chete pama frequency akaderera (kureva, 3-6GHz). Naizvozvo, zvivakwa zveCRLH zvakavakirwa paSMT zvine frequency ranges shoma dzekushanda uye hunhu hwephase hwakati. Semuenzaniso, mumashandisirwo eradiation, zvikamu zvechip zveSMT zvingasakwanisika. Mufananidzo 6 unoratidza chimiro chakagoverwa chakavakirwa paCRLH-TL. Chimiro ichi chinoonekwa neinterdigital capacitance uye short-circuit lines, zvichigadzira series capacitance CL uye parallel inductance LL yeLH zvichiteerana. Capacitance iri pakati pemutsetse neGND inofungidzirwa kuti ndiyo RH capacitance CR, uye inductance inogadzirwa nemagnetic flux inoumbwa ne current flow mu interdigital structure inofungidzirwa kuti ndiyo RH inductance LR.
Mufananidzo 6. Kamuchina kemikoro kadiki keCRLH TL kane divi rimwe chete kanosanganisira ma capacitor epakati pedhijitari uye ma inductor emutsara mupfupi.
Kuti udzidze zvakawanda nezve antenna, ndapota shanyira:
Nguva yekutumira: Nyamavhuvhu-23-2024
