Ka manawa maikaʻi o ka lā.
Ua hoʻohana au i nā makahiki i hala aku nei e noiʻi ana a me ka hana ʻana i nā algorithms like ʻole no ka hoʻoili ʻana i nā hōʻailona spatial i nā ʻano antenna adaptive, a hoʻomau i ka hana ma ke ʻano he ʻāpana o kaʻu hana o kēia manawa. Ma ʻaneʻi, makemake wau e kaʻana like i ka ʻike a me nā hoʻopunipuni aʻu i ʻike ai noʻu iho. Manaʻo wau e lilo kēia i mea pono no ka poʻe e hoʻomaka ana e aʻo i kēia wahi o ka hōʻailona hōʻailona a i ʻole ka poʻe hoihoi.
He aha ke ʻano antenna array?
- he hoʻonohonoho kēia o nā mea antenna i kau ʻia ma kahi ākea ma kekahi ʻano. Hiki ke hōʻike ʻia kahi ʻano maʻalahi o ka adaptive antenna array, a mākou e noʻonoʻo ai, i kēia ʻano:
Ua kapa pinepine ʻia nā antenna adaptive antennas "smart" (). ʻO ka mea e hana ai i kahi antenna array "akamai" ʻo ia ka ʻāpana hoʻoili hōʻailona spatial a me nā algorithms i hoʻokō ʻia i loko. Hoʻopili kēia mau algorithms i ka hōʻailona i loaʻa a hana i kahi pūʻulu o nā coefficient paona $inline$w_1…w_N$inline$, nāna e hoʻoholo i ka amplitude a me ka pae mua o ka hōʻailona no kēlā me kēia mea. Hoʻoholo ka māhele amplitude-phase i hāʻawi ʻia ka lattice holoʻokoʻa holoʻokoʻa. ʻO ka hiki ke synthesize i kahi hiʻohiʻona radiation o ke ʻano i koi ʻia a hoʻololi iā ia i ka wā o ka hoʻoili ʻana i ka hōʻailona kekahi o nā hiʻohiʻona nui o ka adaptive antenna arrays, e hiki ai ke hoʻoponopono i nā pilikia ākea. . Akā ʻo ka mea mua.
Pehea i hana ʻia ai ke ʻano radiation?
hōʻike i ka mana hōʻailona i hoʻokuʻu ʻia ma kekahi ʻaoʻao. No ka maʻalahi, manaʻo mākou he isotropic nā mea lattice, i.e. no kēlā me kēia o lākou, ʻaʻole hilinaʻi ka mana o ka hōʻailona i hoʻokuʻu ʻia i ke kuhikuhi. ʻO ka hoʻonui a i ʻole ka attenuation o ka mana i hoʻokuʻu ʻia e ka grating ma kekahi ʻaoʻao i loaʻa ma muli o ʻO nā hawewe electromagnetic i hoʻokuʻu ʻia e nā ʻano mea like ʻole o ka array antenna. Hiki ke ʻano hoʻohālikelike paʻa no nā hawewe electromagnetic inā lākou , i.e. ʻaʻole pono e loli ka ʻokoʻa o ka pae o nā hōʻailona i ka manawa. ʻO ke kūpono, pono e hoʻomālamalama ʻia kēlā me kēia ʻāpana o ka antenna array ma ka alapine like 'ole $inline$f_{0}$inline$. Eia nō naʻe, ma ka hoʻomaʻamaʻa ʻana, pono e hana kekahi me nā hōʻailona liʻiliʻi me kahi kikoʻī o ka laulā palena ʻole $inline$Delta f << f_{0}$inline$.
E hoʻokuʻu i nā mea AR āpau i ka hōʻailona like me $inline$x_n(t)=u(t)$inline$. A laila ma luna ma ka mea hoʻokipa, hiki ke hōʻike ʻia ka hōʻailona i loaʻa mai ka n-th element ʻano:
$$hōʻike$$a_n(t) = u(t-tau_n)e^{i2pi f_0(t-tau_n)}$$hōʻike$$
kahi $inline$tau_n$inline$ ka lohi o ka hoʻolaha ʻana i ka hōʻailona mai ka mea antenna a i ka wahi e loaʻa ai.
ʻO ia hōʻailona "quasi-harmonic", a no ka hoʻokō ʻana i ke kūlana coherence, pono ka lōʻihi loa i ka hoʻolaha ʻana o nā hawewe electromagnetic ma waena o nā mea ʻelua ʻelua ʻoi aku ka liʻiliʻi ma mua o ka manawa kikoʻī o ka hoʻololi ʻana i ka envelop hōʻailona $inline$T$inline$, i.e. $inline$u(t-tau_n) ≈ u(t-tau_m)$inline$. No laila, hiki ke kākau ʻia ke ʻano no ka hui ʻana o kahi hōʻailona liʻiliʻi penei:
$$hōʻike$$T≈frac{1}{Delta f}>>frac{D_{max}}{c}=max(tau_k-tau_m) $$hōʻike$$
kahi $inline$D_{max}$inline$ ka mamao loa ma waena o nā mea AR, a me $inline$с$inline$ ka wikiwiki o ka māmā.
I ka loaʻa ʻana o kahi hōʻailona, hoʻokō ʻia ka hōʻuluʻulu coherent ma ke ʻano kikohoʻe i loko o ka ʻāpana hana spatial. I kēia hihia, hoʻoholo ʻia ka waiwai paʻakikī o ka hōʻailona kikohoʻe ma ka puka o kēia poloka e ka ʻōlelo:
$$hōʻike$$y=sum_{n=1}^Nw_n^*x_n$$hōʻike$$
ʻOi aku ka maʻalahi o ka hōʻike ʻana i ka ʻōlelo hope ma ke ʻano N-dimensional paʻakikī vector matrix form:
$$hōʻike$$y=(textbf{w},textbf{x})=textbf{w}^Htextbf{x}$$hōʻike$$
kahi w и x he kolamu vectors, a he $inline$(.)^H$inline$ ka hana .
ʻO ka hōʻike Vector o nā hōʻailona kekahi o nā mea maʻamau i ka wā e hana ai me nā antenna arrays, no ka mea ʻae pinepine iā ʻoe e pale i nā helu makemakika paʻakikī. Eia kekahi, ʻo ka ʻike ʻana i kahi hōʻailona i loaʻa i kekahi manawa i ka manawa me kahi vector e hiki ai i kekahi ke abstract mai ka ʻōnaehana kino maoli a hoʻomaopopo i ka mea e hana nei mai ke ʻano o ka geometry.
No ka helu ʻana i ke ʻano o ka radiation o kahi antenna array, pono ʻoe e noʻonoʻo a me ka "hoʻomaka" i kahi pūʻulu o mai nā ʻaoʻao āpau. I kēia hihia, nā waiwai o nā mea vector x hiki ke hōʻike ʻia ma ke ʻano penei:
$$hōʻike$$x_n=s_n=exp{-i(textbf{k}(phi,theta),textbf{r}_n)}$$hōʻike$$
kahi k - , $inline$phi$inline$ a me $inline$theta$inline$ – и , e hōʻike ana i ke kuhikuhi o ka hōʻea ʻana mai o kahi nalu mokulele, $inline$textbf{r}_n$inline$ ka hoʻolikelike o ka mea antenna, $inline$s_n$inline$ ka mea o ka phasing vector. s nalu mokulele me ka nalu nalu k (ma ka palapala Pelekane ua kapa ʻia ka phasing vector i ka steerage vector). Ka hilinaʻi o ka amplitude huinahāhā o ka nui y mai $inline$phi$inline$ a me $inline$theta$inline$ e hoʻoholo ai i ke ʻano hoʻolalelale o ka pūʻulu antenna no ka hoʻokipa ʻana i kahi vector o nā koena kaumaha. w.
Nā hiʻohiʻona o ke ʻano hoʻohālikelike antenna array
He mea maʻalahi ke aʻo ʻana i nā waiwai maʻamau o ke ʻano radiation o nā antenna arrays ma kahi laina antenna equidistant linear i ka mokulele ākea (ʻo ia hoʻi, pili wale ke kumu ma ka angle azimuthal $inline$phi$inline$). Maikaʻi mai ʻelua mau manaʻo: ka helu analytical a me ka hōʻike ʻike.
E helu kāua i ka DN no kahi vector paona wae ($inline$w_n=1, n = 1 ... N$inline$), ma hope o ka wehewehe ʻana. hoʻokokoke.
Makemakika maanei
ʻO ke kuhi ʻana o ka neʻe nalu ma luna o ke koʻi kū pololei: $inline$k_v=-frac{2pi}{lambda}sinphi$inline$
ʻO ka hoʻonohonoho kū pololei o ka mea antenna me ka helu n: $inline$r_{nv}=(n-1)d$inline$
he mea d - ka manawa antenna array (ka mamao ma waena o nā mea pili), λ - lōʻihi nalu. ʻO nā mea vector ʻē aʻe a pau r ua like me ka zero.
Hoʻopaʻa ʻia ka hōʻailona i loaʻa e ka antenna array ma kēia ʻano:
$$hōʻike$$y=sum_{n=1}^{N}1 ⋅exp{i2pi nfrac{d}{lambda}sinphi}$$hōʻike$$
E hoʻohana kākou i ke ʻano no ka и :
$$hōʻike$$y=frac{1-exp{i2pi Nfrac{d}{lambda}sinphi}}{1-exp{i2pi frac{d}{lambda}sinphi}}=frac{sin(pi frac{Nd} {lambda}sinphi)}{sin(pi frac{d}{lambda}sinphi)}exp{ipi frac{d(N-1)}{lambda}sinphi}$$hōʻike$$
ʻO ka hopena, loaʻa iā mākou:
$$hōʻike$$F(phi)=|y|^2=frac{sin^2(pi frac{Nd}{lambda}sinphi)}{sin^2(pi frac{d}{lambda}sinphi)} $ $hōʻike$$
ʻO ka pinepine o ke ʻano hoʻoheheʻe
ʻO ka hopena antenna array radiation pattern kahi hana manawa o ka sine o ke kihi. ʻO kēia ke ʻano ma kekahi mau waiwai o ka ratio d/λ loaʻa iā ia ka ʻokoʻa (hoʻohui) maxima.
ʻAʻole i hoʻohālikelike ʻia i ke ʻano hoʻoheheʻe ʻana o ka pā antenna no N = 5
ʻO ke ʻano hoʻohālikelike maʻamau o ka pā antenna no N = 5 ma ka ʻōnaehana hoʻonohonoho polar
Hiki ke nānā pono ʻia ke kūlana o nā "mea ʻike diffraction". no DN. Eia nō naʻe, e hoʻāʻo mākou e hoʻomaopopo i kahi i hele mai ai lākou mai ke kino a me ka geometrically (ma ka N-dimensional space).
Nā mea hoʻohui vector s he mau huahelu paʻakikī $inline$e^{iPsi n}$inline$, ua hoʻoholo ʻia nā waiwai e ka waiwai o ka huina ākea $inline$Psi = 2pi frac{d}{lambda}sinphi$inline$. Inā he ʻelua kihi ākea e pili ana i nā ʻaoʻao like ʻole o ka hiki ʻana mai o kahi nalu mokulele, nona ka $inline$Psi_1 = Psi_2 + 2pi m$inline$, a laila ʻelua mau mea:
- Ma ke kino: ʻO nā mua nalu o ka mokulele e hele mai ana mai kēia mau ʻaoʻao e hoʻoulu i ka puʻunaue amplitude-phase like o nā oscillations electromagnetic ma nā mea o ka array antenna.
- Geometric: no keia mau aoao elua.
ʻO nā kuhikuhi o ka hiki ʻana mai o ka nalu e pili ana i kēia ʻano like me ka ʻike o ka antenna array a ʻaʻole hiki ke ʻike ʻia kekahi i kekahi.
Pehea e hoʻoholo ai i ka ʻāpana o nā kihi kahi e waiho mau ai ka palena nui o ka DP? E hana kākou i kēia ma kahi kokoke i ka zero azimuth mai kēia mau manaʻo: ʻo ka nui o ka neʻe ʻana o ka pae ma waena o ʻelua mau mea pili e pono e moe i ka pae mai $inline$-pi$inline$ a i $inline$pi$inline$.
$$hōʻike$$-pi<2pifrac{d}{lambda}sinphi
I ka hoʻoholo ʻana i kēia ʻano like ʻole, loaʻa iā mākou ke kūlana no ka ʻāina kūʻokoʻa ma kahi kokoke i ka zero:
$$hōʻike$$|sinphi|
Hiki ke ʻike ʻia ka nui o ka ʻāpana o ka ʻokoʻa ma ke kihi e pili ana i ka pilina d/λ. ^ E Ha yM. Inā d = 0.5λ, a laila ʻo kēlā me kēia kuhikuhi o ka hōʻea ʻana o ka hōʻailona he "kūʻokoʻa", a ʻo ka ʻāpana o ke ʻano kūʻokoʻa e uhi i ka piha o nā kihi. Ina d = 2.0λ, a laila ua like nā kuhikuhi 0, ±30, ±90. Hōʻike ʻia nā lobes diffraction ma ke ʻano radiation.
ʻO ka maʻamau, ʻimi ʻia nā lobes diffraction e hoʻohana ʻia me nā mea antenna directional. I kēia hihia, ʻo ka ʻōnaehana radiation piha o ka antenna array ka huahana o ke kumu o hoʻokahi mea a me kahi ʻano o nā mea isotropic. E koho pinepine ʻia nā ʻāpana o ke ʻano o hoʻokahi mea e pili ana i ke kūlana no ka ʻāpana o ka unambiguity o ka array antenna.
laula lobe nui
ʻano hana ʻenekinia no ka helu ʻana i ka laula o ka lobe nui o kahi ʻōnaehana antena: $inline$Delta phi ≈ frac{lambda}{D}$inline$, kahi ʻo D ka nui ʻano o ka antenna. Hoʻohana ʻia ka formula no nā ʻano antenna like ʻole, me nā aniani. E hōʻike mākou he kūpono ia no nā antenna arrays.
E hoʻoholo kākou i ka laulā o ka lobe nui e nā zeros mua o ke kumu ma kahi kokoke i ka palena nui. Mea helu no ka $inline$F(phi)$inline$ nalowale ke $inline$sinphi=mfrac{lambda}{dN}$inline$. ʻO nā helu mua e pili ana i ka m = ±1. $inline$frac{lambda}{dN}<<1$inline$ loaʻa iā mākou $inline$Delta phi = 2frac{lambda}{dN}$inline$.
ʻO ka maʻamau, hoʻoholo ʻia ka laulā o ke kumu kuhikuhi antenna e ka hapalua o ka mana (-3 dB). I kēia hihia, e hoʻohana i ka ʻōlelo:
$$hōʻike$$Delta phi≈0.88frac{lambda}{dN}$$hōʻike$$
Pākuhi:
Hiki ke hoʻomalu ʻia ka laulā o ka lobe nui e ka hoʻonohonoho ʻana i nā waiwai amplitude ʻokoʻa no nā coefficients paona antenna. E noʻonoʻo kākou i ʻekolu mahele:
- Ka mahele like 'ole o ka amplitude (kaumaha 1): $inline$w_n=1$inline$.
- Ke emi iho nei nā waiwai amplitude i nā ʻaoʻao o ka pākuʻi (kaumaha 2): $inline$w_n=0.5+0.3cos(2pifrac{n-1}{N}-pifrac{N-1}{N})$inline$
- Ke piʻi aʻe nei nā waiwai amplitude i nā ʻaoʻao o ka pākuʻi (kaumaha 3): $inline$w_n=0.5-0.3cos(2pifrac{n-1}{N}-pifrac{N-1}{N})$inline$
Hōʻike ke kiʻi i nā ʻano hoʻohālike maʻamau maʻamau i ka pālākiō logarithmic:
Hiki ke ʻike ʻia nā hiʻohiʻona ma lalo o ke kiʻi: ʻo ka hāʻawi ʻana i nā amplitudes coefficient kaumaha e emi ana i nā ʻaoʻao o ka ʻaoʻao e alakaʻi i ka hoʻonui ʻana i ka lobe nui o ke kumu, akā he emi i ka pae o nā lobes ʻaoʻao. Ke piʻi nei nā waiwai amplitude i nā ʻaoʻao o ka antenna array, ma kahi ʻē aʻe, alakaʻi i kahi hōʻemi o ka lobe nui a me ka piʻi ʻana o ke kiʻekiʻe o nā lobes ʻaoʻao. He mea maʻalahi ke noʻonoʻo i ka hoʻopaʻa ʻana i nā hihia ma aneʻi:
- ʻO nā amplitudes o nā koena kaumaha o nā mea a pau koe nā mea ʻoi loa, ua like ia me ka ʻole. ʻO nā paona no nā mea i waho loa ua like me hoʻokahi. I kēia hihia, lilo ka lattice i like me ka AR ʻelua ʻeleʻele me kahi manawa D = (N-1)d. ʻAʻole paʻakikī ke koho i ka laulā o ka petal nui me ka hoʻohana ʻana i ke ʻano i hōʻike ʻia ma luna. I kēia hihia, e lilo nā ʻaoʻao ʻaoʻao i ka diffraction maxima a e kūlike me ka nui nui.
- Ua like ke kaumaha o ka mea kikowaena me hoʻokahi, a ua like nā mea ʻē aʻe me ka ʻole. I kēia hihia, loaʻa iā mākou hoʻokahi antenna me kahi ʻano hoʻohālikelike isotropic.
Kuhikuhi o ka nui nui
No laila, ua nānā mākou pehea e hiki ai iā ʻoe ke hoʻololi i ka laulā o ka lobe nui o ka AP AP. I kēia manawa e ʻike kākou pehea e hoʻokele ai i ke ala. E hoomanao kakou no ka hoailona loaa. Makemake mākou i ka nui o ke ʻano hoʻolalelale e nānā i kekahi ʻaoʻao $inline$phi_0$inline$. 'O ia ho'i, pono e loa'a ka mana nui mai kēia kuhikuhi. Pili kēia kuhikuhi i ka vector pae ʻana $inline$textbf{s}(phi_0)$inline$ in N-dimensional vector space, a ua wehewehe ʻia ka mana i loaʻa e like me ka huinahā o ka huahana scalar o kēia vector phasing a me ka vector o nā koena kaumaha. w. ʻO ka huahana scalar o nā vectors ʻelua ke kiʻekiʻe i ka wā e loaʻa ai , i.e. $inline$textbf{w}=beta textbf{s}(phi_0)$inline$, kahi β - kekahi mea maʻamau. No laila, inā koho mākou i ka vector paona e like me ka vector phasing no ke kuhikuhi i koi ʻia, e hoʻololi mākou i ka palena kiʻekiʻe o ke kumu radiation.
E noʻonoʻo i kēia mau mea kaumaha ma ke ʻano he laʻana: $inline$textbf{w}=textbf{s}(10°)$inline$
$$hōʻike$$w_n=exp{i2pifrac{d}{lambda}(n-1) hewa(10pi/180)}$$hōʻike$$
ʻO ka hopena, loaʻa iā mākou kahi ʻano radiation me ka nui nui ma ke kuhikuhi o 10 °.
I kēia manawa, hoʻohana mākou i nā coefficient paona like, akā ʻaʻole no ka hoʻokipa hōʻailona, akā no ka lawe ʻana. Pono e noʻonoʻo ma aneʻi i ka wā e hoʻouna ai i kahi hōʻailona, e hoʻololi ke kuhikuhi o ka vector hawewe i ka ʻaoʻao. ʻO kēia keʻano o nā mea no ka hoʻokipa ʻana a me ka hoʻouna ʻana ʻokoʻa lākou i ka hōʻailona o ka exponent, i.e. pili pū ʻia me ka hoʻopili paʻakikī. Ma muli o ka hopena, loaʻa iā mākou ka palena kiʻekiʻe o ke ʻano radiation no ka hoʻouna ʻana i ke kuhikuhi o -10 °, ʻaʻole i kūlike me ka nui o ke ʻano radiation no ka hoʻokipa ʻana me nā coefficient kaumaha like. No ka hoʻoponopono ʻana i ke kūlana, pono ia e e hoʻopili i ka conjugation paʻakikī i nā coefficient kaumaha pū kekahi.
ʻO ka hiʻohiʻona i wehewehe ʻia o ka hoʻokumu ʻana i nā hiʻohiʻona no ka hoʻokipa a me ka hoʻouna ʻana e mālama mau ʻia i ka wā e hana ai me nā antenna arrays.
E pāʻani kākou me ke ʻano o ka radiation
He mau kiʻekiʻe
E hoʻonoho mākou i ka hana o ka hoʻokumu ʻana i ʻelua maxima nui o ke ʻano radiation ma ke kuhikuhi: -5 ° a me 10 °. No ka hana ʻana i kēia, koho mākou ma ke ʻano he vector paona i ka huina kaumaha o nā vectors phasing no nā kuhikuhi pili.
$$hōʻike$$textbf{w} = betatextbf{s}(10°)+(1-beta)textbf{s}(-5°)$$hōʻike$$
Hoʻoponopono i ka ratio β Hiki iā ʻoe ke hoʻoponopono i ka ratio ma waena o nā petals nui. Eia hou he mea maʻalahi ke nānā aku i nā mea e hana nei ma ka lewa vector. Ina β ʻoi aku ka nui ma mua o 0.5, a laila e pili kokoke ana ka vector o nā coefficient paona s(10°), i ole ia i s(-5°). ʻO ka pili kokoke i ka vector kaumaha i kekahi o nā phasors, ʻoi aku ka nui o ka huahana scalar pili, a no laila ke kumukūʻai o ka DP kiʻekiʻe e pili ana.
Eia nō naʻe, pono e noʻonoʻo ʻia he palena palena ʻole nā petals nui, a inā makemake mākou e hoʻolohe i ʻelua mau ʻaoʻao kokoke, a laila e hui pū kēia mau petals i hoʻokahi, e kuhikuhi ana i kekahi ala waena.
Hoʻokahi kiʻekiʻe a me ka ʻole
I kēia manawa, e hoʻāʻo kākou e hoʻololi i ka palena kiʻekiʻe o ke ʻano radiation i ke kuhikuhi $inline$phi_1=10°$inline$ a ma ka manawa like e hoʻopaʻa i ka hōʻailona e hele mai ana mai ke kuhikuhi $inline$phi_2=-5°$inline$. No ka hana ʻana i kēia, pono ʻoe e hoʻonohonoho i ka DN zero no ke kihi pili. Hiki iā ʻoe ke hana penei:
$$hōʻike$$textbf{w}=textbf{s}_1-frac{textbf{s}_2^Htextbf{s}_1}{N}textbf{s}_2$$display$$
kahi $inline$textbf{s}_1 = textbf{s}(10°)$inline$, a me $inline$textbf{s}_2 = textbf{s}(-5°)$inline$.
ʻO ke ʻano geometric o ke koho ʻana i kahi vector kaumaha penei. Makemake mākou i kēia vector w Ua loaʻa ka manaʻo kiʻekiʻe loa ma $inline$textbf{s}_1$inline$ a i ka manawa like ʻo ka orthogonal i ka vector $inline$textbf{s}_2$inline$. Hiki ke hōʻike ʻia ka vector $inline$textbf{s}_1$inline$ ma ke ʻano he ʻelua huaʻōlelo: kahi vector collinear $inline$textbf{s}_2$inline$ a me kahi vector orthogonal $inline$textbf{s}_2$inline$. No ka hoʻokō ʻana i ka ʻōlelo pilikia, pono e koho i ka ʻāpana ʻelua ma ke ʻano he vector o nā coefficient paona w. Hiki ke helu ʻia ka ʻāpana collinear ma ke kuhi ʻana i ka vector $inline$textbf{s}_1$inline$ ma luna o ka vector maʻamau $inline$frac{textbf{s}_2}{sqrt{N}}$inline$ me ka hoʻohana ʻana i ka huahana scalar.
$$hōʻike$$textbf{s}_{1||}=frac{textbf{s}_2}{sqrt{N}}frac{textbf{s}_2^Htextbf{s}_1}{sqrt{N}} $$hōʻike$$
No laila, i ka unuhi ʻana i kāna ʻāpana collinear mai ka vector phasing kumu mua $inline$textbf{s}_1$inline$, loaʻa iā mākou ka vector kaumaha i makemake ʻia.
Kekahi mau memo hou
- Ma nā wahi a pau ma luna, ua haʻalele wau i ka pilikia o ka hoʻoponopono ʻana i ka vector kaumaha, ʻo ia hoʻi. kona loa. No laila, ʻaʻole pili ka normalization o ka vector kaumaha i nā hiʻohiʻona o ke ʻano o ka radiation antenna array: ke kuhikuhi o ka nui nui, ka laulā o ka lobe nui, etc. Hiki ke hōʻike ʻia ʻaʻole pili kēia maʻamau i ka SNR ma ka puka o ka ʻāpana hana spatial. Ma kēia mea, i ka wā e noʻonoʻo ai i nā algorithms hoʻoponopono hōʻailona spatial, e ʻae pinepine mākou i kahi ʻāpana normalization o ka vector kaumaha, ʻo ia hoʻi. $inline$textbf{w}^Htextbf{w}=1$inline$
- Hoʻoholo ʻia nā mea hiki ke hana i kahi hiʻohiʻona o kahi antenna array e ka helu o nā mea N. ʻO ka nui o nā mea, ʻoi aku ka nui o nā mea hiki. ʻOi aku ka nui o nā degere o ke kūʻokoʻa i ka wā e hoʻokō ai i ka hoʻoili paona spatial, ʻoi aku ka nui o nā koho no ka "wili" i ka vector paona ma ke ākea N-dimensional.
- I ka loaʻa ʻana o nā hiʻohiʻona radiation, ʻaʻole i noho kino ka antenna array, a aia kēia mau mea āpau i ka "manaʻo" wale nō o ka ʻāpana computing e hana i ka hōʻailona. 'O ia ho'i, hiki i ka manawa like ke ho'ohui i kekahi mau hi'ohi'ona a ho'oponopono kū'oko'a i nā hō'ailona e hele mai ana mai nā 'ao'ao like 'ole. I ka hihia o ka hoʻouna ʻana, ʻoi aku ka paʻakikī o nā mea a pau, akā hiki nō hoʻi ke synthesize i kekahi mau DN e hoʻouna i nā kahawai ʻikepili like ʻole. Kapa ʻia kēia ʻenehana i nā ʻōnaehana kamaʻilio .
- Ke hoʻohana nei i ka code matlab i hōʻike ʻia, hiki iā ʻoe ke pāʻani a puni me ka DN iā ʻoe iho
kuhi% antenna array settings N = 10; % number of elements d = 0.5; % period of antenna array wLength = 1; % wavelength mode = 'receiver'; % receiver or transmitter % weights of antenna array w = ones(N,1); % w = 0.5 + 0.3*cos(2*pi*((0:N-1)-0.5*(N-1))/N).'; % w = 0.5 - 0.3*cos(2*pi*((0:N-1)-0.5*(N-1))/N).'; % w = exp(2i*pi*d/wLength*sin(10/180*pi)*(0:N-1)).'; % b = 0.5; w = b*exp(2i*pi*d/wLength*sin(+10/180*pi)*(0:N-1)).' + (1-b)*exp(2i*pi*d/wLength*sin(-5/180*pi)*(0:N-1)).'; % b = 0.5; w = b*exp(2i*pi*d/wLength*sin(+3/180*pi)*(0:N-1)).' + (1-b)*exp(2i*pi*d/wLength*sin(-3/180*pi)*(0:N-1)).'; % s1 = exp(2i*pi*d/wLength*sin(10/180*pi)*(0:N-1)).'; % s2 = exp(2i*pi*d/wLength*sin(-5/180*pi)*(0:N-1)).'; % w = s1 - (1/N)*s2*s2'*s1; % w = s1; % normalize weights w = w./sqrt(sum(abs(w).^2)); % set of angle values to calculate pattern angGrid_deg = (-90:0.5:90); % convert degree to radian angGrid = angGrid_deg * pi / 180; % calculate set of steerage vectors for angle grid switch (mode) case 'receiver' s = exp(2i*pi*d/wLength*bsxfun(@times,(0:N-1)',sin(angGrid))); case 'transmitter' s = exp(-2i*pi*d/wLength*bsxfun(@times,(0:N-1)',sin(angGrid))); end % calculate pattern y = (abs(w'*s)).^2; %linear scale plot(angGrid_deg,y/max(y)); grid on; xlim([-90 90]); % log scale % plot(angGrid_deg,10*log10(y/max(y))); % grid on; % xlim([-90 90]);
He aha nā pilikia e hiki ke hoʻoponopono ʻia me ka hoʻohana ʻana i kahi array antenna adaptive?
ʻO ka hoʻokipa maikaʻi loa o kahi hōʻailona ʻike ʻole ʻiaInā ʻaʻole ʻike ʻia ke kuhikuhi o ka hōʻea ʻana o ka hōʻailona (a inā he multipath ke ala kamaʻilio, aia ma ke ʻano he nui nā kuhikuhi), a laila ma ka nānā ʻana i ka hōʻailona i loaʻa e ka antenna array, hiki ke hana i kahi vector kaumaha maikaʻi loa. w no laila, ʻoi aku ka nui o ka SNR ma ka hoʻopuka ʻana o ka ʻāpana hana spatial.
ʻO ka hoʻokipa hōʻailona maikaʻi loa e kū'ē i ka walaʻau hopeEia ka pilikia penei: ʻike ʻia nā ʻāpana spatial o ka hōʻailona pono i manaʻo ʻia, akā aia nā kumu o ka hoʻopilikia ʻana i ke kaiapuni o waho. Pono e hoʻonui i ka SINR ma ka puka AP, e hōʻemi ana i ka mana o ke keakea i ka hoʻokipa hōʻailona.
ʻO ka hoʻouna hōʻailona maikaʻi loa i ka mea hoʻohanaHoʻoholo ʻia kēia pilikia ma nā ʻōnaehana kamaʻilio kelepona (4G, 5G), a me Wi-Fi. He maʻalahi ka manaʻo: me ke kōkua ʻana o nā hōʻailona hoʻokele kūikawā i ke kahawai manaʻo o ka mea hoʻohana, loiloi ʻia nā hiʻohiʻona spatial o ke kaila kamaʻilio, a ma ke kumu, koho ʻia ka vector o nā coefficient paona i kūpono no ka hoʻouna ʻana.
ʻO ka hoʻonui nui ʻana o nā kahawai ʻikepiliAdaptive antenna arrays e ʻae i ka hoʻouna ʻana i ka ʻikepili i kekahi mau mea hoʻohana i ka manawa like ma ka alapine like, e hana ana i kahi hiʻohiʻona pilikino no kēlā me kēia o lākou. Kapa ʻia kēia ʻenehana ʻo MU-MIMO a ke hoʻokō ʻia nei i kēia manawa (a ma kahi ʻē aʻe) i nā ʻōnaehana kamaʻilio. Hāʻawi ʻia ka hiki o ka multiplexing spatial, no ka laʻana, ma ka 4G LTE mobile communication standard, IEEE802.11ay Wi-Fi standard, a me 5G mobile communication standards.
ʻO nā ʻano antenna maʻamau no nā radarHiki i nā ʻāpana antenna kikohoʻe ke hiki, me ka hoʻohana ʻana i kekahi mau mea hoʻouna antenna, e hana i kahi ʻano antenna virtual o nā nui nui loa no ka hana hōʻailona. Loaʻa i ka mānoanoa nā hiʻohiʻona a pau o ka mea maoli, akā pono ka liʻiliʻi o ka lako e hoʻokō.
Ka manaʻo o nā ʻāpana o nā kumu radiationHiki i nā ʻāpana antenna adaptive ke hoʻoponopono i ka pilikia o ka helu ʻana i ka helu, ka mana, nā kumu hoʻokuʻu lekiō, e hoʻokumu i kahi pilina helu ma waena o nā hōʻailona mai nā kumu like ʻole. ʻO ka pono nui o ka adaptive antenna arrays i kēia mea ʻo ia ka hiki ke hoʻoponopono i nā kumu radiation kokoke. ʻO nā kumu, ka mamao angular ma waena o ka liʻiliʻi ma mua o ka laulā o ka lobe nui o ke ʻano hoʻohālikelike antenna array (). Hiki kēia ma muli o ka hōʻike vector o ka hōʻailona, ke kumu hoʻohālike kaulana, a me nā mea hana o ka makemakika laina.
Mahalo no ka nānā
Source: www.habr.com