Nhau - Ongororo yeMetamaterial Transmission Line Antennas

I. Nhanganyaya
Metamaterials inogona kunyatsotsanangurwa seyakagadzirwa zvimiro kuti igadzire mamwe emagetsi magineti zvinhu zvisipo zvakasikwa. Metamaterials ine negative permittivity uye negative permeability inonzi metamaterials (LHMs). LHM dzakadzidzwa zvakanyanya munharaunda dzesainzi neinjiniya. Muna 2003, maLHM akatumidzwa seimwe yepamusoro gumi yebudiriro yesainzi yenguva yazvino nemagazini yeScience. Zvishandiso zvitsva, pfungwa, uye zvishandiso zvakagadziridzwa nekushandisa yakasarudzika zvivakwa zveLHM. Iyo nzira yekufambisa (TL) inzira inoshanda yekugadzira iyo inogona zvakare kuongorora misimboti yeLHMs. Kuenzaniswa neTLs yechinyakare, iyo inonyanya kukosha yemetamaterial TLs ndeye controllability yeTL paramita (propagation yenguva dzose) uye hunhu impedance. Kudzora kwemetamaterial TL paramita kunopa mazano matsva ekugadzira antenna zvimiro zvine saizi yakawanda compact, kuita kwepamusoro, uye mabasa matsva. Mufananidzo 1 (a), (b), uye (c) inoratidza isingarasikike yedunhu modhi yeyakachena yekurudyi-ruoko rwekutapurirana mutsara (PRH), yakachena yekuruboshwe-ruoko rwekutapurirana mutsara (PLH), uye inoumbwa kuruboshwe-kurudyi-kurudyi tambo yekufambisa ( CRLH), zvichiteerana. Sezvinoratidzwa muMufananidzo 1(a), iyo PRH TL yakaenzana yedunhu modhi inowanzova musanganiswa wenhevedzano inductance uye shunt capacitance. Sezvinoratidzwa mumufananidzo 1(b), iyo PLH TL yedunhu modhi musanganiswa weshunt inductance uye akateedzana capacitance. Mumashandisirwo anoshanda, hazvigoneke kushandisa PLH wedunhu. Izvi zvinokonzerwa neisingadzivisike parasitic akatevedzana inductance uye shunt capacitance mhedzisiro. Naizvozvo, hunhu hwemutsara wekuruboshwe wekuruboshwe unogona kuitika parizvino zvese zvinoumbwa neruboshwe-neruboshwe zvimiro, sezvakaratidzwa mumufananidzo 1(c).

Mufananidzo 1 Different transmission line circuit modhi

Iyo yekuparadzira nguva dzose (γ) yemutsetse wekutumira (TL) inoverengerwa se: γ = α + jβ = Sqrt (ZY), apo Y uye Z inomiririra kubvuma uye impedance zvichiteerana. Tichifunga nezveCRLH-TL, Z uye Y inogona kuratidzwa se:

Yunifomu CRLH TL ichave neinotevera hukama hwekupararira:

Chikamu chekugara β chinogona kunge chiri nhamba chaiyo kana nhamba yekufungidzira. Kana β iri chaiyo mukati meiyo frequency renji, pane passband mukati meiyo frequency renji nekuda kwemamiriro γ=jβ. Kune rimwe divi, kana β iri nhamba yekufungidzira chete mukati meiyo frequency renji, pane inomira mukati meiyo frequency renji nekuda kwechimiro γ=α. Iyi stopband yakasarudzika kune CRLH-TL uye haipo muPRH-TL kana PLH-TL. Mifananidzo 2 (a), (b), uye (c) inoratidza kupararira curves (kureva, ω - β ukama) yePRH-TL, PLH-TL, uye CRLH-TL, zvichiteerana. Kubva pamakwikwi ekupararira, kukurumidza kweboka (vg = ∂ω / ∂β) uye chikamu chekufamba (vp = ω / β) chetambo yekufambisa inogona kutorwa uye inofungidzirwa. Kune PRH-TL, inogona zvakare kuverengerwa kubva kucurve kuti vg uye vp zvakafanana (kureva, vpvg> 0). Kune PLH-TL, iyo curve inoratidza kuti vg uye vp hazvina kufanana (kureva, vpvg <0). The dispersion curve yeCRLH-TL inoratidzawo kuvapo kweLH dunhu (kureva, vpvg <0) neRH dunhu (kureva, vpvg> 0). Sezvinogona kuonekwa kubva Mufananidzo 2(c), nokuda kweCRLH-TL, kana γ iri nhamba chaiyo chaiyo, pane bhendi rekumira.

Mufananidzo 2 Dispersion curves yemitsara yakasiyana-siyana yekufambisa

Kazhinji, iwo akateedzana uye anowirirana resonances eCRLH-TL akasiyana, ayo anonzi nyika isina kuenzana. Nekudaro, kana iyo nhevedzano uye parallel resonance frequencies yakafanana, inodaidzwa kuti yakaenzana mamiriro, uye mhedzisiro yakapfava yakaenzana yedunhu modhi inoratidzwa muFigure 3(a).

Mufananidzo 3 Circuit modhi uye dispersion curve yecomposite yeruboshwe-ruoko rwekufambisa tambo

Sezvo kuwanda kunowedzera, maitiro ekuparadzira eCRLH-TL zvishoma nezvishoma anowedzera. Izvi zvinodaro nekuti danho rekumhanya (kureva, vp=ω/β) rinowedzera kutsamira pa frequency. Pamafafitera akaderera, CRLH-TL inotongwa neLH, nepo pakakwirira frequencies, CRLH-TL inotongwa neRH. Izvi zvinoratidza huviri hunhu hweCRLH-TL. The equilibrium CRLH-TL dispersion diagram inoratidzwa muFigure 3(b). Sezvinoratidzwa mumufananidzo 3(b), shanduko kubva kuLH kuenda kuRH inoitika pa:

Ipo ω0 ndiyo inoshandura nguva. Naizvozvo, mune yakaringana, shanduko yakatsetseka inoitika kubva kuLH kuenda kuRH nekuti γ inhamba yekufungidzira. Naizvozvo, hapana kumira kweiyo yakaenzana CRLH-TL dispersion. Kunyange zvazvo β iri zero pa ω0 (isingagumi hukama kune inotungamirwa yavelength, kureva, λg=2π/|β|), masaisai achiri kupararira nekuti vg pa ω0 haisi zero. Saizvozvo, pa ω0, danho rekuchinja i zero yeTL yehurefu d (kureva, φ= - βd=0). The phase advance (kureva, φ>0) inoitika muLH frequency range (kureva, ω<ω0), uye kunonoka kwechikamu (kureva, φ<0) kunoitika muRH frequency renji (kureva, ω>ω0). Kune CRLH TL, iyo hunhu impedance inotsanangurwa seizvi:

Iko ZL neZR ndiyo PLH nePRH impedances, zvichiteerana. Kune iyo isina kuenzana kesi, iyo hunhu impedance inoenderana nehuwandu. Iyo equation iri pamusoro inoratidza kuti iyo yakaenzana kesi yakazvimirira pane frequency, saka inogona kuve neyakakura bandwidth match. Iyo TL equation yakatorwa pamusoro yakafanana neiyo constitutive paramita inotsanangura iyo CRLH zvinhu. Iyo nguva yekuparadzira yeTL ndeye γ=jβ=Sqrt(ZY). Tichifunga nezve kupararira kwekugara kwezvinhu (β=ω x Sqrt(εμ)), iyo inotevera equation inogona kuwanikwa:

Saizvozvowo, iyo hunhu impedance yeTL, kureva, Z0=Sqrt(ZY), yakafanana neiyo hunhu impedance yechinhu, kureva, η=Sqrt(μ/ε), iyo inoratidzwa se:

Iyo refractive index yekuenzanisa uye isina kuenzana CRLH-TL (kureva, n = cβ / ω) inoratidzwa muMufananidzo 4. Mumufananidzo 4, refractive index yeCRLH-TL muhuwandu hwayo hweLH haina kunaka uye refractive index muRH yayo. range iri positive.

Fig. 4 Yakajairika refractive indices yepakati uye isina kuenzana CRLH TLs.

1. LC network
Nekukanda mabhendi eLC masero anoratidzwa muMufananidzo 5(a), yakajairika CRLH-TL ine hurefu hwakafanana hwehurefu d inogona kuvakwa nguva nenguva kana isiri-nguva. Kazhinji, kuitira kuti uve nechokwadi chekureruka kwekuverenga uye kugadzira kweCRLH-TL, dunhu rinofanirwa kuve nguva nenguva. Kuenzaniswa nemuenzaniso weMufananidzo 1 (c), sero redunhu reMufananidzo 5 (a) harina ukuru uye kureba kwemuviri kudiki zvisingaite (kureva, Δz mumamita). Tichifunga nezvehurefu hwayo hwemagetsi θ=Δφ (rad), chikamu cheLC cell chinogona kuratidzwa. Nekudaro, kuti unyatso kuona iyo inoshandiswa inductance uye capacitance, kureba kwemuviri p kunoda kusimbiswa. Sarudzo yetekinoroji yekushandisa (senge microstrip, coplanar waveguide, pamusoro pegomo zvikamu, nezvimwewo) ichakanganisa saizi yemuviri yeLC cell. Iyo LC cell yeFigure 5 (a) yakafanana neyokuwedzera modhi yeMufananidzo 1(c), uye muganho wayo p = Δz→0. Zvinoenderana nechimiro chakafanana p→ 0 muMufananidzo 5(b), TL inogona kuvakwa (nekudonha LC maseru) yakaenzana neyakakwana yunifomu CRLH-TL nehurefu d, kuti TL iite seyakafanana kune emagetsi mafungu.

Mufananidzo 5 CRLH TL yakavakirwa paLC network.

Kune iyo LC sero, tichifunga nezve periodic boundary mamiriro (PBCs) akafanana neiyo Bloch-Floquet theorem, hukama hwekupararira kweLC cell hunoratidzwa nekuratidzwa sezvinotevera:

Iwo akateedzana impedance (Z) uye shunt admittance (Y) yeLC cell inotemerwa neinotevera equations:

Sezvo kureba kwemagetsi kweiyo unit LC wedunhu idiki kwazvo, kufungidzira kwaTaylor kunogona kushandiswa kuwana:

2. Kuitwa Kwenyama
Muchikamu chakapfuura, iyo LC network yekugadzira CRLH-TL yakakurukurwa. Manetiweki akadaro eLC anogona kungoonekwa nekutora zvinhu zvemuviri zvinogona kuburitsa inodiwa capacitance (CR neCL) uye inductance (LR neLL). Mumakore achangopfuura, kushandiswa kwepamusoro-soro tekinoroji (SMT) chip zvikamu kana zvikamu zvakagoverwa kwakwezva kufarira kukuru. Microstrip, stripline, coplanar waveguide kana mamwe matekinoroji akafanana anogona kushandiswa kuona zvakagoverwa. Pane zvinhu zvakawanda zvekufunga nezvazvo pakusarudza SMT machipi kana akagoverwa zvikamu. SMT-based CRLH zvimiro zvakajairika uye zviri nyore kuita maererano nekuongorora nekugadzira. Izvi zvinokonzerwa nekuvapo kwe-off-the-shelf SMT chip components, izvo zvisingadi kugadziriswa nekugadzira zvichienzaniswa nezvikamu zvakagoverwa. Zvisinei, kuwanikwa kwezvikamu zveSMT zvakapararira, uye zvinowanzoshanda chete pakaderera (kureva, 3-6GHz). Naizvozvo, SMT-yakavakirwa CRLH zvimiro zvine mashoma ekushandisa frequency renji uye chaiwo echikamu maitiro. Semuyenzaniso, mukuvheneka maapplication, SMT chip zvikamu zvingave zvisingakwanisike. Mufananidzo 6 unoratidza chimiro chakagoverwa chakavakirwa paCRLH-TL. Iyo dhizaini inozadzikiswa neinterdigital capacitance uye pfupi-yedunhu mitsetse, ichigadzira yakatevedzana capacitance CL uye parallel inductance LL yeLH zvakateerana. Iyo capacitance pakati pemutsara neGND inofungidzirwa kuva RH capacitance CR, uye inductance inogadzirwa nemagnetic flux inoumbwa nekuyerera kwezvino mu interdigital structure inofungidzirwa kuva RH inductance LR.