Sanibonani.
Ngichithe iminyaka embalwa edlule ngicwaninga futhi ngenza ama-algorithms ahlukahlukene okucubungula isignali yendawo kuma-antenna alandelanayo, futhi ngiyaqhubeka nokwenza njengengxenye yomsebenzi wami wamanje. Lapha ngithanda ukwabelana ngolwazi namaqhinga engizitholele wona. Ngethemba ukuthi lokhu kuzoba usizo kubantu abaqala ukufunda le ndawo yokucubungula amasignali noma labo abamane nje banentshisekelo.
Iyini i-antenna evumelanayo?
– lena isethi yezakhi ze-antenna ezibekwe emkhathini ngandlela thize. Isakhiwo esenziwe lula se-antenna evumelanayo, esizoyicubungula, singamelwa ngaleli fomu elilandelayo:
Izinti eziguquguqukayo zivame ukubizwa ngokuthi izimpondo “ezihlakaniphile” (). Okwenza i-antenna "smart" iyunithi yokucubungula isignali yendawo kanye nama-algorithms asetshenziswa kuyo. Lawa ma-algorithms ahlaziya isignali eyamukelwe futhi akhe isethi yama-coefficients esisindo $inline$w_1…w_N$inline$, anquma ubude nesigaba sokuqala sesiginali ye-elementi ngayinye. Ukusabalalisa kwesigaba se-amplitude esinikeziwe kuyanquma i-lattice yonke iphelele. Ikhono lokuhlanganisa iphethini yemisebe yomumo odingekayo futhi uyiguqule ngesikhathi sokucutshungulwa kwesignali ingenye yezici eziyinhloko ze-antenna arrays eguquguqukayo, evumela ukuxazulula izinkinga eziningi. . Kodwa izinto zokuqala kuqala.
Yakhiwa kanjani iphethini yemisebe?
libonisa amandla esignali akhishwa ohlangothini oluthile. Ukuze kube lula, sicabanga ukuthi izakhi ze-lattice ziyi-isotropic, i.e. ngayinye yazo, amandla esignali ekhishiwe awancikile ekuqondeni. Ukukhuliswa noma ukuncishiswa kwamandla akhishwa i-grating ngendlela ethile kutholakala ngenxa Amagagasi kagesi akhishwa yizici ezihlukahlukene ze-antenna. Iphethini yokuphazamiseka ezinzile yamagagasi kagesi kungenzeka kuphela uma kwenzeka , i.e. umehluko wesigaba samasignali akufanele ushintshe ngokuhamba kwesikhathi. Ngokufanelekile, ingxenye ngayinye ye-antenna kufanele ikhanye kumvamisa efanayo yenkampani yenethiwekhi $inline$f_{0}$inline$. Nokho, ekusebenzeni umuntu kufanele asebenze ngamasignali ebhande elincane anobubanzi obunomkhawulo ongu-$inline$Delta f << f_{0}$inline$.
Vumela zonke izici ze-AR zikhiphe isignali efanayo nge $inline$x_n(t)=u(t)$inline$. Bese kuqhubeke kumamukeli, isignali etholwe ku-n-th element ingamelwa kuyo ifomu:
$$display$$a_n(t) = u(t-tau_n)e^{i2pi f_0(t-tau_n)}$$display$$
lapho i-$inline$tau_n$inline$ iwukubambezeleka kokusakazwa kwesignali kusuka entweni yothi kuya endaweni yokwamukela.
Isiginali enjalo "quasi-harmonic", kanye nokwanelisa isimo sokuhambisana, kuyadingeka ukuthi ukubambezeleka okuphezulu ekusakazweni kwamagagasi kagesi phakathi kwanoma yiziphi izici ezimbili kungaphansi kakhulu kunesikhathi sesici soshintsho kumvilophu yesignali $inline$T$inline$, i.e. $inline$u(t-tau_n) ≈ u(t-tau_m)$inline$. Ngakho-ke, isimo sokuhambisana kwesignali ye-narrowband singabhalwa kanje:
$$display$$T≈frac{1}{Delta f}>>frac{D_{max}}{c}=max(tau_k-tau_m) $$display$$
lapho i-$inline$D_{max}$inline$ iyibanga eliphezulu phakathi kwama-elementi e-AR, futhi i-$inline$с$inline$ ijubane lokukhanya.
Uma isignali yamukelwe, ukuhlanganisa okuhambisanayo kwenziwa ngedijithali kuyunithi yokucubungula indawo. Kulokhu, inani eliyinkimbinkimbi lesiginali yedijithali ekuphumeni kwaleli bhulokhi kunqunywa inkulumo ethi:
$$display$$y=sum_{n=1}^Nw_n^*x_n$$display$$
Kungcono kakhulu ukumela inkulumo yokugcina efomini Ama-N-dimensional complex vectors akwifomu le-matrix:
$$display$$y=(textbf{w},textbf{x})=textbf{w}^Htextbf{x}$$display$$
kuphi w и x amavekhtha ekholomu, futhi $inline$(.)^H$inline$ kuwumsebenzi .
Ukumelwa kweVector yamasiginali kungenye yezinto eziyisisekelo lapho usebenza ngama-antenna array, ngoba ngokuvamile ikuvumela ukuthi ugweme ukubala kwezibalo ezinzima. Ngaphezu kwalokho, ukuhlonza isignali etholwe ngesikhathi esithile nge-vector ngokuvamile kuvumela umuntu ukuthi akhiphe ohlelweni lwangempela lomzimba futhi aqonde ukuthi kwenzekani ngempela ngokombono wejometri.
Ukuze ubale iphethini yemisebe yochungechunge lwe-antenna, udinga "ukwethula" ngokwengqondo nangokulandelanayo isethi kusuka kuzo zonke izindlela ezingenzeka. Kulokhu, amanani wezinto ze-vector x ingamelwa ngaleli fomu:
$$display$$x_n=s_n=exp{-i(textbf{k}(phi,theta),textbf{r}_n)}$$display$$
kuphi k - , $inline$phi$inline$ kanye ne-$inline$theta$inline$ - и , okubonisa isiqondiso sokufika kwegagasi lendiza, i-$inline$textbf{r}_n$inline$ iwukuxhumanisa kwento ye-antenna, i-$inline$s_n$inline$ iyingxenye ye-vector ehlukanisayo s indiza yendiza ene-vector yamagagasi k (ezincwadini zesiNgisi i-vector ehlukanisayo ibizwa ngokuthi i-steerage vector). Ukuncika kwe-amplitude eyisikwele yenani y kusuka ku-$inline$phi$inline$ kanye ne-$inline$theta$inline$ inquma iphethini yemisebe yochungechunge lwe-antenna yokwamukela ivekhtha enikeziwe yama-coefficients anesisindo w.
Izici zephethini yemisebe ye-antenna array
Kuyasiza ukufunda izici ezijwayelekile zephethini yemisebe yezinhlaka ze-antenna kuhlu lwe-antenna elinganayo endizeni evundlile (okungukuthi, iphethini incike kuphela ku-engeli ye-azimuthal $inline$phi$inline$). Ilula ngokubuka amaphuzu amabili: izibalo zokuhlaziya kanye nokwethulwa okubukwayo.
Ake sibale i-DN yeyunithi ye-vector yesisindo ($inline$w_n=1, n = 1 ... N$inline$), silandela okuchaziwe sondela.
Izibalo lapha
Ukuboniswa kwevektha yegagasi ku-eksisi eqondile: $inline$k_v=-frac{2pi}{lambda}sinphi$inline$
Ukuxhumanisa okuqondile kwe-elementi ye-antenna enenkomba n: $inline$r_{nv}=(n-1)d$inline$
kuyinto d - isikhathi se-antenna (ibanga phakathi kwezinto eziseduze), λ - ubude begagasi. Zonke ezinye izakhi ze-vector r zilingana noziro.
Isiginali etholwe yi-antenna irekhodwa ngaleli fomu elilandelayo:
$$display$$y=sum_{n=1}^{N}1 ⋅exp{i2pi nfrac{d}{lambda}sinphi}$$display$$
Masisebenzise ifomula ye и :
$$display$$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}$$display$$
Ngenxa yalokho sithola:
$$display$$F(phi)=|y|^2=frac{sin^2(pi frac{Nd}{lambda}sinphi)}{sin^2(pi frac{d}{lambda}sinphi)} $ $bonisa$$
Imvamisa yephethini yemisebe
Iphethini yemisebe ye-antenna ewumphumela ingumsebenzi wezikhathi ezithile we-sine ye-engeli. Lokhu kusho ukuthi ngamavelu athile esilinganiso d/λ ine-diffraction (eyengeziwe) maxima.
Iphethini yemisebe engajwayelekile yohlelo lwe-antenna ye-N = 5
Iphethini yemisebe evamile ye-antenna array ye-N = 5 kusistimu yokuxhumanisa indawo epholile
Ukuma "kwezitholi ze-diffraction" kungabukwa ngokuqondile kwe-DN. Kodwa-ke, sizozama ukuqonda ukuthi zivelaphi ngokomzimba nangokwejometri (endaweni ye-N-dimensional).
Izinto i-vector s ama-exponents ayinkimbinkimbi $inline$e^{iPsi n}$inline$, amanani ayo anqunywa inani le-engeli ejwayelekile $inline$Psi = 2pi frac{d}{lambda}sinphi$inline$. Uma kunama-engeli ajwayelekile amabili ahambisana nezikhombisi-ndlela ezihlukene zokufika kwegagasi lendiza, okuthi $inline$Psi_1 = Psi_2 + 2pi m$inline$, lokhu kusho izinto ezimbili:
- Ngokomzimba: amaza amaza endiza aqhamuka kulezi zikhombisi-ndlela adala ukusatshalaliswa kwesigaba se-amplitude okufanayo kwama-oscillations kagesi ezintweni ze-antenna.
- Ngokwejometri: ngoba lezi zikhombisi-ndlela ezimbili ziyaqondana.
Izikhombisi-ndlela zokufika kwegagasi ezihlobene ngale ndlela ziyalingana ukusuka endaweni yokubuka ye-antenna futhi azihlukaniseki ukusuka kwenye.
Unganquma kanjani isifunda sama-engeli lapho kuhlale kulele kuphela ubukhulu obubodwa be-DP? Masenze lokhu eduze ne-azimuth enguziro kusukela kokucatshangelwa okulandelayo: ubukhulu bokushintshwa kwesigaba phakathi kwezinto ezimbili ezincikene kufanele bube kububanzi obusuka ku-$inline$-pi$inline$ kuya ku-$inline$pi$inline$.
$$display$$-pi<2pifrac{d}{lambda}sinphi
Ukuxazulula lokhu kungalingani, sithola isimo sendawo ehlukile endaweni eyiziro:
$$display$$|sinphi|
Kungabonakala ukuthi ubukhulu besifunda sokuhluka nge-engeli buncike ebuhlotsheni d/λ. Uma d = 0.5λ, khona-ke isiqondiso ngasinye sokufika kwesignali “singesomuntu ngamunye”, futhi indawo ehlukile ihlanganisa ububanzi obugcwele bama-engeli. Uma d = 2.0λ, bese izikhombisi-ndlela 0, ±30, ±90 ziyalingana. Ama-diffraction lobe avela kuphethini yemisebe.
Imvamisa, ama-diffraction lobes afunwa ukuthi acindezelwe kusetshenziswa izakhi ze-antenna eziqondisayo. Kulokhu, iphethini yemisebe ephelele ye-antenna iwumkhiqizo wephethini yento eyodwa kanye nohlu lwezakhi ze-isotropic. Amapharamitha wephethini ye-elementi eyodwa ngokuvamile akhethwa ngokusekelwe esimweni sesifunda sokungaqondakali kochungechunge lwe-antenna.
Ububanzi belobe eyinhloko
ifomula yobunjiniyela yokulinganisa ububanzi belobe eyinhloko yesistimu ye-antenna: $inline$Delta phi ≈ frac{lambda}{D}$inline$, lapho u-D eyisici sikasayizi we-antenna. Ifomula isetshenziselwa izinhlobo ezahlukene zezimpondo, kuhlanganise nezibuko. Masibonise ukuthi ivumelekile futhi kuma-antenna array.
Ake sinqume ububanzi be-lobe eyinhloko ngoziro bokuqala bephethini eduze komkhawulo omkhulu. Inombolo nge-$inline$F(phi)$inline$ inyamalala lapho i-$inline$sinphi=mfrac{lambda}{dN}$inline$. Oziro bokuqala bahambisana no-m = ±1. $inline$frac{lambda}{dN}<1$inline$ sithola i-$inline$Delta phi = 2frac{lambda}{dN}$inline$.
Ngokuvamile, ububanzi bephethini yokuqondisa kwezinti bunqunywa izinga lamandla ayingxenye (-3 dB). Kulokhu, sebenzisa isisho:
$$display$$Delta phi≈0.88frac{lambda}{dN}$$display$$
Isibonelo:
Ububanzi be-lobe eyinhloko bungalawulwa ngokusetha amanani e-amplitude ahlukene ama-coefficients okulinganisa ama-antenna. Ake sicabangele ukusatshalaliswa okuthathu:
- Ukusabalalisa kwe-amplitude okufanayo (isisindo 1): $inline$w_n=1$inline$.
- Amanani e-amplitude ehla aya ngasemaphethelweni egrating (izisindo 2): $inline$w_n=0.5+0.3cos(2pifrac{n-1}{N}-pifrac{N-1}{N})$inline$
- Amanani ama-amplitude akhuphuka aya ngasemaphethelweni egridi (izisindo 3): $inline$w_n=0.5-0.3cos(2pifrac{n-1}{N}-pifrac{N-1}{N})$inline$
Isibalo sibonisa umphumela wamaphethini wemisebe evamile esikalini se-logarithmic:
Amathrendi alandelayo angalandelelwa kusuka kumfanekiso: ukusatshalaliswa kwe-coefficient amplitudes yesisindo eyancipha ukuya emaphethelweni ochungechunge kuholela ekwandeni kwe-lobe eyinhloko yephethini, kodwa ukwehla kwezinga lama-lobes aseceleni. Amanani we-amplitude akhuphuka abheke emaphethelweni ochungechunge lwe-antenna, ngokuphambene nalokho, aholela ekuncipheni kwe-lobe eyinhloko kanye nokwanda kwezinga lama-lobes aseceleni. Kuyafaneleka ukucabangela amacala okukhawulela lapha:
- Ama-amplitudes we-weighting coefficients yazo zonke izakhi ngaphandle kwalawo adlulele alingana noziro. Izisindo zezakhi zangaphandle zilingana nesisodwa. Kulokhu, i-lattice ilingana nezinto ezimbili ze-AR ezinenkathi D = (N-1)d. Akunzima ukulinganisa ububanzi be-petal eyinhloko usebenzisa ifomula evezwe ngenhla. Kulokhu, izindonga eziseceleni zizophenduka zibe yi-diffraction maxima futhi zihambisane nobukhulu obukhulu.
- Isisindo se-elementi emaphakathi silingana neyodwa, futhi zonke ezinye zilingana noziro. Kulokhu, sithole i-antenna eyodwa enephethini yemisebe ye-isotropic.
Isikhombisi-ndlela sobukhulu obukhulu
Ngakho-ke, sibheke ukuthi ungalungisa kanjani ububanzi be-lobe eyinhloko ye-AP AP. Manje ake sibone indlela yokuqondisa indlela. Masikhumbule okwesiginali eyamukelwe. Masifune ubukhulu bephethini yemisebe bubheke ohlangothini oluthile $inline$phi_0$inline$. Lokhu kusho ukuthi amandla aphezulu kufanele atholwe kulokhu. Lesi sikhombisi-ndlela sihambisana ne-vector ehlukanisayo ethi $inline$textbf{s}(phi_0)$inline$ in N-Isikhala se-vector esingu-dimensional, namandla atholiwe achazwa njengesikwele somkhiqizo oyisikali wale vector ehlukanisayo kanye ne-vector ye-weighting coefficients. w. Umkhiqizo we-scalar wama-vectors amabili uphezulu uma benza , i.e. $inline$textbf{w}=beta textbf{s}(phi_0)$inline$, lapho β - isici esithile esijwayelekile. Ngakho-ke, uma sikhetha i-vector yesisindo elingana ne-vector ehlukanisayo yesiqondiso esidingekayo, sizozungeza ubukhulu bephethini yemisebe.
Cabangela izici zesisindo ezilandelayo njengesibonelo: $inline$textbf{w}=textbf{s}(10°)$inline$
$$display$$w_n=exp{i2pifrac{d}{lambda}(n-1)sin(10pi/180)}$$display$$
Ngenxa yalokho, sithola iphethini yemisebe enomkhawulo oyinhloko ekuqondeni kuka-10 °.
Manje sisebenzisa ama-coefficients wokulinganisa afanayo, kodwa hhayi ukwamukela isignali, kodwa ukudlulisa. Kuyafaneleka ukucabangela lapha ukuthi lapho udlulisela isignali, isiqondiso se-vector ye-wave sishintsha siye kokuphambene. Lokhu kusho ukuthi izakhi ukwamukela nokudlulisela ziyahlukahluka kusibonakaliso se-exponent, i.e. zixhunywe ngokuhlanganisa okuyinkimbinkimbi. Ngenxa yalokho, sithola ubukhulu bephethini yemisebe yokudlulisela ngaku--10°, engahambelani nobukhulu bephethini yemisebe yokwamukela ngama-coefficients esisindo afanayo. Ukuze ulungise isimo, kuyadingeka sebenzisa ukuhlanganiswa okuyinkimbinkimbi kuma-coefficients wesisindo futhi.
Isici esichaziwe sokwakheka kwamaphethini okwamukela nokudluliswa kufanele kuhlale kukhunjulwa lapho kusetshenzwa ngama-antenna array.
Asidlale ngephethini yemisebe
Ukuphakama okuningana
Ake sibeke umsebenzi wokwenza ama-maxima amabili ayinhloko wephethini yemisebe ohlangothini: -5 ° no-10 °. Ukuze senze lokhu, sikhetha njengevekhtha yesisindo isamba esisindiwe samavekhtha ahlukanisayo wezinkomba ezihambisanayo.
$$display$$textbf{w} = betatextbf{s}(10°)+(1-beta)textbf{s}(-5°)$$display$$
Ukulungisa isilinganiso β Ungakwazi ukulungisa isilinganiso phakathi kwamacembe amakhulu. Lapha futhi kulula ukubheka ukuthi kwenzekani endaweni ye-vector. Uma β inkulu kuno-0.5, bese i-vector ye-weighting coefficients ilele eduze kwayo s(10°), ngaphandle kwalokho s(-5°). Lapho i-vector yesisindo isondela kwenye ye-phasors, inkulu umkhiqizo ohambisanayo we-scalar, ngakho-ke inani le-DP ephezulu ehambisanayo.
Kodwa-ke, kufanelekile ukucabangela ukuthi womabili amacembe ayinhloko anobubanzi obulinganiselwe, futhi uma sifuna ukuxhuma ezindaweni ezimbili eziseduze, khona-ke la macembe azohlangana abe munye, aqondiswe ekuqondeni okuphakathi nendawo.
Okukodwa okuphezulu kanye noziro
Manje ake sizame ukulungisa ubukhulu bephethini yemisebe ukuya ngaku-$inline$phi_1=10°$inline$ futhi ngesikhathi esifanayo sicindezele isignali evela ohlangothini $inline$phi_2=-5°$inline$. Ukuze wenze lokhu, udinga ukusetha i-DN zero ye-engeli ehambisanayo. Ungakwenza lokhu kanje:
$$display$$textbf{w}=textbf{s}_1-frac{textbf{s}_2^Htextbf{s}_1}{N}textbf{s}_2$$display$$
lapho $inline$textbf{s}_1 = textbf{s}(10°)$inline$, kanye ne-$inline$textbf{s}_2 = textbf{s}(-5°)$inline$.
Incazelo yejometri yokukhetha i-vector yesisindo imi kanje. Sifuna le vector w inomkhawulo ophezulu wokuqagela ku-$inline$textbf{s}_1$inline$ futhi ngesikhathi esifanayo i-orthogonal ku-vector engu-$inline$textbf{s}_2$inline$. Ivekhtha ethi $inline$textbf{s}_1$inline$ ingamelwa njengamagama amabili: i-collinear vector $inline$textbf{s}_2$inline$ kanye nevektha ye-orthogonal $inline$textbf{s}_2$inline$. Ukwanelisa isitatimende senkinga, kubalulekile ukukhetha ingxenye yesibili njengevektha yama-coefficients wokulinganisa. w. Ingxenye ye-collinear ingabalwa ngokuveza i-vector engu-$inline$textbf{s}_1$inline$ ku-vector evamile engu-$inline$frac{textbf{s}_2}{sqrt{N}}$inline$ kusetshenziswa umkhiqizo wesikali.
$$display$$textbf{s}_{1||}=frac{textbf{s}_2}{sqrt{N}}frac{textbf{s}_2^Htextbf{s}_1}{sqrt{N}} $$bonisa$$
Ngokufanelekile, sikhipha ingxenye yayo ye-collinear kwivektha yezigaba yokuqala engu-$inline$textbf{s}_1$inline$, sithola ivektha yesisindo edingekayo.
Amanye amanothi engeziwe
- Kuyo yonke indawo ngenhla, ngiyekile indaba yokujwayelekile kwe-vector yesisindo, i.e. ubude bayo. Ngakho-ke, ukujwayelekile kwe-vector yesisindo akuthinti izici zephethini yemisebe ye-antenna: isiqondiso sobukhulu obuyinhloko, ububanzi be-lobe eyinhloko, njll. Kungase futhi kuboniswe ukuthi lokhu kujwayelekile akuthinti i-SNR ekuphumeni kweyunithi yokucubungula indawo. Mayelana nalokhu, lapho sicabangela ama-algorithms okucubungula isignali yendawo, sivame ukwamukela ukujwayela kweyunithi ye-vector yesisindo, i.e. $inline$textbf{w}^Htextbf{w}=1$inline$
- Amathuba okwenza iphethini ye-antenna anqunywa inani lezinto ezi-N. Uma izakhi eziningi, kuba banzi amathuba. Amadigri enkululeko engeziwe lapho usebenzisa ukucutshungulwa kwesisindo sendawo, izinketho eziningi zokuthi “ungasonta” kanjani ivektha yesisindo esikhaleni esingu-N-dimensional.
- Lapho ithola amaphethini emisebe, i-antenna array ayikho ngokomzimba, futhi konke lokhu kukhona kuphela "emcabangweni" weyunithi yekhompuyutha ecubungula isignali. Lokhu kusho ukuthi ngesikhathi esifanayo kungenzeka ukuhlanganisa amaphethini amaningana futhi ngokuzimela ukucubungula amasignali avela ezinkomba ezahlukene. Endabeni yokudlulisela, yonke into iyinkimbinkimbi kakhulu, kodwa kungenzeka futhi ukuhlanganisa ama-DN amaningana ukudlulisa imifudlana yedatha ehlukene. Lobu buchwepheshe ezinhlelweni zokuxhumana bubizwa ngokuthi .
- Usebenzisa ikhodi yethulwe ye-matlab, ungadlala nawe nge-DN ngokwakho
Ikhodi% 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]);
Yiziphi izinkinga ezingaxazululwa kusetshenziswa i-antenna eguquguqukayo?
Ukwamukela okufanelekile kwesiginali engaziwaUma isiqondiso sokufika kwesignali singaziwa (futhi uma isiteshi sokuxhumana singu-multipath, ngokuvamile kunezikhombisi-ndlela ezimbalwa), khona-ke ngokuhlaziya isignali etholwe yi-antenna array, kungenzeka ukwakha i-vector yesisindo esiphezulu. w ukuze i-SNR ekuphumeni kweyunithi yokucubungula indawo ibe ephezulu.
Ukwamukela isignali efanele ngokumelene nomsindo wangemuvaLapha inkinga ibekwe kanje: imingcele yendawo yesiginali ewusizo elindelwe iyaziwa, kodwa kunemithombo yokuphazamiseka endaweni yangaphandle. Kuyadingeka ukukhulisa i-SINR ekuphumeni kwe-AP, unciphise umthelela wokuphazamiseka ekwamukelweni kwesignali ngangokunokwenzeka.
Ukudluliselwa kwesiginali kumsebenzisiLe nkinga ixazululwa ezinhlelweni zokuxhumana zeselula (4G, 5G), kanye naku-Wi-Fi. Incazelo ilula: ngosizo lwezimpawu ezikhethekile zokushayela esiteshini sempendulo yomsebenzisi, izici zendawo zesiteshi sokuxhumana ziyahlolwa, futhi ngesisekelo salo, i-vector ye-weighting coefficients efanelekile yokudlulisela ikhethiwe.
Ukuphindwaphindwa kwesikhala kokusakazwa kwedathaAmalungu afanayo e-antenna avumela ukudluliswa kwedatha kubasebenzisi abambalwa ngesikhathi esisodwa kumafrikhwensi afanayo, okwenza iphethini ngayinye ngayinye yabo. Lobu buchwepheshe bubizwa nge-MU-MIMO futhi okwamanje busetshenziswa ngenkuthalo (futhi ndawana thile kakade) ezinhlelweni zokuxhumana. Amathuba okuphindaphindeka kwendawo anikeziwe, isibonelo, kuzinga lokuxhumana kweselula le-4G LTE, i-IEEE802.11ay ejwayelekile ye-Wi-Fi, kanye nezindinganiso zokuxhumana zeselula ze-5G.
I-antenna ebonakalayo yama-radarUhlu lwe-antenna yedijithali yenza kube nokwenzeka, kusetshenziswa izakhi ezimbalwa ze-antenna, ukwakha uhlu lwe-antenna olubonakalayo lwamasayizi amakhulu kakhulu okucubungula isignali. Igridi ebonakalayo inazo zonke izici zeyoqobo, kodwa idinga izingxenyekazi zekhompuyutha ezincane ukuze zisetshenziswe.
Isilinganiso samapharamitha wemithombo yemisebeAma-antenna afanayo avumela ukuxazulula inkinga yokulinganisa inombolo, amandla, imithombo yokuphuma komsakazo, sungula ukuxhumana kwezibalo phakathi kwamasignali avela emithonjeni ehlukene. Inzuzo enkulu yama-antenna alandelanayo kulolu daba yikhono lokuxazulula kakhulu imithombo eseduze yemisebe. Imithombo, ibanga eliyi-angular phakathi kwalo elingaphansi kobubanzi belobe eyinhloko yephethini yemisebe yochungechunge lwe-antenna (). Lokhu kungenzeka kakhulu ngenxa yokumelwa kwevekhtha yesiginali, imodeli yesiginali eyaziwayo, kanye nemishini yezibalo eqondile.
Ngiyabonga ukunakwa
Source: www.habr.com