Nūhou - He Manaʻo o ka Metamaterial Transmission Line Antennas

I. Hoolauna
Hiki ke wehewehe maikaʻi ʻia nā metamaterials e like me nā hale i hoʻolālā ʻia e hana i kekahi mau waiwai electromagnetic ʻaʻole i kū maoli. Ua kapa ʻia nā metamaterial me ka ʻae ʻole a me ka permeability maikaʻi ʻole. Ua aʻo nui ʻia nā LHM ma nā kaiāulu ʻepekema a ʻenekinia. I ka makahiki 2003, ua koho ʻia ʻo LHM i kekahi o nā ʻumi ʻepekema holomua o kēia au e ka makasina Science. Ua kūkulu ʻia nā noi, nā manaʻo, a me nā mea hana hou ma o ka hoʻohana ʻana i nā waiwai kūʻokoʻa o LHM. He ala hoʻolālā maikaʻi ke ala hoʻouna laina (TL) e hiki ke kālailai i nā loina o nā LHM. Hoʻohālikelike ʻia me nā TL kuʻuna, ʻo ka hiʻohiʻona koʻikoʻi o nā TL metamaterial ʻo ia ka mana o nā ʻāpana TL (propagation mau) a me ka impedance hiʻohiʻona. Hāʻawi ka mana o nā ʻāpana TL metamaterial i nā manaʻo hou no ka hoʻolālā ʻana i nā hale antenna me ka nui compact, ka hana kiʻekiʻe, a me nā hana hou. Kiʻi 1 (a), (b), a me (c) hōʻike i nā hiʻohiʻona pohō ʻole o ka laina hoʻouna lima ʻākau maʻemaʻe (PRH), laina hoʻouna lima hema maʻemaʻe (PLH), a me ka laina hoʻouna lima hema hema ( CRLH), kēlā me kēia. E like me ka mea i hōʻike ʻia ma ke Kiʻi 1(a), ʻo ka PRH TL equivalent circuit circuit ka mea maʻamau ka hui pū ʻana o ka inductance series a me ka capacitance shunt. E like me ka mea i hōʻike ʻia ma ke Kiʻi 1(b), ʻo ke kumu hoʻohālike kaapuni PLH TL kahi hui o ka inductance shunt a me ka capacitance series. Ma nā noi kūpono, ʻaʻole hiki ke hoʻokō i kahi kaapuni PLH. ʻO kēia ma muli o ka inductance series parasitic hiki ʻole ke pale ʻia a me nā hopena capacitance shunt. No laila, ʻo nā hiʻohiʻona o ka laina hoʻouna lima hema i hiki ke hoʻomaopopo ʻia i kēia manawa, ʻo ia nā mea hana lima hema a me ka lima ʻākau, e like me ka mea i hōʻike ʻia ma ke Kiʻi 1(c).

Kiʻi 1 Nā hiʻohiʻona kaapuni laina hoʻouna like ʻole

ʻO ka hoʻolaha mau (γ) o ka laina hoʻouna (TL) i helu ʻia e like me: γ=α+jβ=Sqrt(ZY), kahi Y a me Z e hōʻike ana i ka ʻae a me ka impedance. E noʻonoʻo ana iā CRLH-TL, Z a me Y hiki ke hōʻike ʻia e like me:

E loaʻa i kahi CRLH TL like ʻole ka pilina hoʻopuehu:

Hiki i ka māhele β ke helu maoli maoli a i ʻole ka helu noʻonoʻo. Inā 'oia'i'o loa 'o β i loko o ka laula'au alapine, aia kekahi passband i loko o ke alapinepine ma muli o ke kūlana γ=jβ. Ma ka ʻaoʻao ʻē aʻe, inā he helu noʻonoʻo maʻemaʻe ka β i loko o kahi ʻano alapine, aia kahi paʻa i loko o ke alapine ma muli o ke kūlana γ=α. He kū hoʻokahi kēia pahu hoʻomaha iā CRLH-TL a ʻaʻole i loaʻa ma PRH-TL a i ʻole PLH-TL. Hōʻike nā kiʻi 2 (a), (b), a me (c) i nā ʻōkuhi hoʻopuehu (ʻo ia hoʻi, ka pilina ω - β) o PRH-TL, PLH-TL, a me CRLH-TL. Ma muli o nā ʻāpana hoʻopuehu, hiki ke loaʻa a koho ʻia ka wikiwiki o ka hui (vg=∂ω/∂β) a me ka wikiwiki o ka pae (vp=ω/β) o ka laina hoʻouna. No PRH-TL, hiki ke hoʻomaopopo ʻia mai ka pihi ʻana o ka vg a me ka vp i like (ʻo ia hoʻi, vpvg>0). No PLH-TL, hōʻike ka ʻaʻe ʻaʻole like ka vg a me ka vp (ʻo ia hoʻi, vpvg<0). Hōʻike pū ʻia ka ʻāpana hoʻopuehu o CRLH-TL i ke ola o ka ʻāina LH (ʻo ia hoʻi, vpvg <0) a me ka ʻāpana RH (ʻo ia hoʻi, vpvg > 0). E like me ka mea i ʻike ʻia ma ke Kiʻi 2(c), no CRLH-TL, inā he helu maoli maʻemaʻe ʻo γ, aia kahi pūʻina kū.

Kiʻi 2 Nā ʻōkuhi hoʻopuehu o nā laina hoʻouna like ʻole

ʻO ka mea maʻamau, ʻokoʻa ka moʻo a me nā resonances like o kahi CRLH-TL, i kapa ʻia he mokuʻāina ʻole. Eia nō naʻe, inā like ka moʻo a me nā alapine resonance like, ua kapa ʻia ʻo ia he kūlana kaulike, a ua hōʻike ʻia ke kumu hoʻohālike i hoʻohālikelike ʻia ma ke kiʻi 3(a).

Kiʻi 3 Ke kŘkohu kaapuni a me ka pihi hoʻopuehu o ka laina hoʻouna lima hema

Ke piʻi aʻe ka alapine, piʻi mālie nā ʻano hoʻopuehu o CRLH-TL. ʻO kēia no ka mea e pili nui ana ka wikiwiki o ka pae (ʻo ia hoʻi, vp=ω/β) i ke alapine. Ma nā alapine haʻahaʻa, hoʻomalu ʻia ʻo CRLH-TL e LH, ʻoiai ma nā alapine kiʻekiʻe, hoʻomalu ʻia ʻo CRLH-TL e RH. Hōʻike kēia i ke ʻano ʻelua o CRLH-TL. Hōʻike ʻia ke kiʻi hoʻopuehu CRLH-TL equilibrium ma ke Kiʻi 3(b). E like me ka mea i hōʻike ʻia ma ke Kiʻi 3(b), hiki ke hoʻololi mai LH i RH ma:

Aia ka ω0 ke alapine hoʻololi. No laila, ma ka hihia kaulike, hiki mai ka ho'ololi ma'alahi mai LH a i RH no ka mea, he helu no'ono'o wale 'o γ. No laila, ʻaʻohe mea paʻa no ka hoʻopuehu CRLH-TL kaulike. ʻOiai he zero ka β ma ω0 (pili palena ʻole i ka lōʻihi nalu alakaʻi ʻia, ʻo ia hoʻi, λg=2π/|β|), hoʻolaha mau ka nalu no ka mea ʻaʻole ʻole ka vg ma ω0. Pēlā nō, ma ω0, ʻaʻole ka neʻe ʻana o ka pae no kahi TL o ka lōʻihi d (ʻo ia hoʻi, φ= - βd=0). Loaʻa ka pae mua (ie, φ>0) i ka laina alapine LH (ʻo ia hoʻi, ω<ω0), a ʻo ka hoʻihoʻi ʻana o ka pae (ie, φ<0) i loko o ka laina alapine RH (ie, ω>ω0). No kahi CRLH TL, ua wehewehe ʻia ka impedance ʻano penei:

Ma kahi o ZL a me ZR ka PLH a me PRH impedances, kēlā me kēia. No ka hihia kaulike ʻole, pili ka impedance ʻano i ke alapine. Hōʻike ka hoʻohālikelike ma luna nei he kūʻokoʻa ka hihia kaulike i ke alapine, no laila hiki ke loaʻa i kahi pāʻani bandwidth ākea. ʻO ka hoʻohālikelike TL i loaʻa ma luna nei ua like ia me nā ʻāpana constitutive e wehewehe i ka mea CRLH. ʻO ka hoʻolaha mau o TL ʻo γ=jβ=Sqrt(ZY). Hāʻawi ʻia i ka hoʻolaha mau o ka mea (β=ω x Sqrt(εμ)), hiki ke loaʻa ka hoʻohālikelike penei:

Pēlā nō, ua like ka impedance hiʻona o TL, ʻo ia hoʻi, Z0=Sqrt(ZY), me ka impedance hiʻona o ka mea, ʻo ia hoʻi, η=Sqrt(μ/ε), i hōʻike ʻia penei:

Hōʻike ʻia ka helu hoʻohālikelike o ka CRLH-TL kaulike a me ke kaulike ʻole (ʻo ia hoʻi, n = cβ/ω) ma ke Kiʻi 4. Ma ka Figure 4, ʻo ka helu refractive o ka CRLH-TL i kona LH he mea ʻino a ʻo ka helu refractive i kona RH. maikaʻi ka laulā.

Fig. 4 Nā hōʻailona refractive maʻamau o nā CRLH TL i kaulike a kaulike ʻole.

1. LC pūnaewele
Ma ka hoʻokuʻu ʻana i nā pūnaewele LC bandpass i hōʻike ʻia ma ke Kiʻi 5(a), hiki ke kūkulu ʻia kahi CRLH-TL maʻamau me ka lōkahi kūpono o ka lōʻihi d hiki ke kūkulu ʻia i kēlā me kēia manawa a i ʻole. Ma keʻano laulā, i mea e hōʻoia ai i ka maʻalahi o ka helu ʻana a me ka hana ʻana o CRLH-TL, pono ke kaapuni i ka manawa. Ke hoʻohālikelike ʻia me ke kumu hoʻohālike o ke Kiʻi 1(c), ʻaʻohe nui o ke kelepona kaapuni o ke Kiʻi 5(a) a he liʻiliʻi loa ka lōʻihi kino (ʻo ia hoʻi, Δz i nā mika). E noʻonoʻo ana i kona lōʻihi uila θ=Δφ (rad), hiki ke hōʻike ʻia ka māhele o ka cell LC. Eia naʻe, i mea e ʻike maoli ai i ka inductance i hoʻopili ʻia a me ka capacitance, pono e hoʻokumu ʻia kahi lōʻihi kino p. ʻO ke koho ʻana i ka ʻenehana noi (e like me ka microstrip, coplanar waveguide, nā ʻāpana mauna o luna, a me nā mea ʻē aʻe) e hoʻopilikia i ka nui kino o ka cell LC. Ua like ka pūnaewele LC o ke Kiʻi 5(a) me ke kumu hoʻohālike o ka Kiʻi 1(c), a me kona palena p=Δz→0. E like me ke kūlana kūlike p→0 ma ke Kiʻi 5(b), hiki ke kūkulu ʻia kahi TL (ma ka hoʻoheheʻe ʻana i nā pūnaewele LC) i like me ka CRLH-TL ʻaʻahu kūpono me ka lōʻihi d, i ʻike like ʻia ka TL me nā hawewe electromagnetic.

Kiʻi 5 CRLH TL ma muli o ka pūnaewele LC.

No ke kelepona LC, me ka noʻonoʻo ʻana i nā kūlana palena manawa (PBCs) e like me ka theorem Bloch-Floquet, ua hōʻike ʻia ka pilina dispersion o ka cell LC a hōʻike ʻia penei:

Hoʻoholo ʻia ka impedance series (Z) a me ka shunt admittance (Y) o ke kelepona LC e kēia mau hoohalike:

Ma muli o ka liʻiliʻi loa o ka lōʻihi uila o ka ʻāpana LC kaapuni, hiki ke hoʻohana ʻia ʻo Taylor approximation e loaʻa ai:

2. Hoʻokō kino
Ma ka ʻāpana mua, ua kūkākūkā ʻia ka pūnaewele LC e hana i ka CRLH-TL. Hiki ke ʻike ʻia kēlā mau pūnaewele LC ma o ka lawe ʻana i nā ʻāpana kino e hiki ke hana i ka capacitance pono (CR a me CL) a me ka inductance (LR a me LL). I kēia mau makahiki i hala iho nei, ua hoihoi nui ʻia ka hoʻohana ʻana i nā ʻāpana chips surface mount technology (SMT) a i ʻole nā mea hoʻokaʻawale. Hiki ke hoʻohana ʻia ka Microstrip, stripline, coplanar waveguide a i ʻole nā ʻenehana like ʻole no ka ʻike ʻana i nā ʻāpana puʻupuʻu. Nui nā mea e noʻonoʻo ai i ke koho ʻana i nā ʻāpana SMT a i ʻole nā mea hoʻokaʻawale. ʻOi aku ka maʻamau a maʻalahi hoʻi ka hoʻokō ʻana i nā hale CRLH ma SMT ma ke ʻano o ka nānā ʻana a me ka hoʻolālā. ʻO kēia ma muli o ka loaʻa ʻana o nā ʻāpana chip SMT ma waho o ka papa, ʻaʻole koi i ka hoʻoponopono hou ʻana a me ka hana ʻana i hoʻohālikelike ʻia i nā ʻāpana i puʻunaue ʻia. Eia nō naʻe, ua hoʻopuehu ʻia ka loaʻa ʻana o nā ʻāpana SMT, a hana maʻamau lākou ma nā alapine haʻahaʻa (ʻo ia hoʻi, 3-6GHz). No laila, ua kaupalena nā ʻōnaehana CRLH i hoʻokumu ʻia e SMT i nā pae alapine hana a me nā hiʻohiʻona kikoʻī. No ka laʻana, i ka hoʻomālamalama ʻana i nā noi, ʻaʻole hiki ke kūpono nā ʻāpana chip SMT. Hōʻike ke kiʻi 6 i kahi hoʻolālā puʻupuʻu ma muli o CRLH-TL. Hoʻomaopopo ʻia ke ʻano e ka capacitance interdigital a me nā laina pōkole pōkole, e hana ana i ka capacitance CL a me ka inductance LL o LH i kēlā me kēia. ʻO ka capacitance ma waena o ka laina a me GND ua manaʻo ʻia ʻo ia ka RH capacitance CR, a ʻo ka inductance i hana ʻia e ka flux magnetic i hana ʻia e ke kahe o kēia manawa i loko o ka interdigital structure i manaʻo ʻia ʻo ia ka RH inductance LR.