Uxhumano LTE - kuyini? Mode, isakhiwo kanye nokusebenza inethiwekhi LTE

Inethiwekhi LTE esanda evunywe 3GPP. Ngokusetshenziswa ezifana inethiwekhi emoyeni esibonakalayo bengathola engakaze ibonwe yokusebenza imingcele ngokuya ngesilinganiso esiphezulu lapho idatha ngocansi, ukubambezeleka amaphakethe ngokudlulisela, kanye nekghono Spectral. Abalobi bathi ukwethulwa inethiwekhi LTE evumela ukusetshenziswa bohlu umsakazo, ubuchwepheshe multiantennuyu, isiteshi lithathelwe sishintshashintsha kalula ukuhlela izindlela, kabusha inhlangano idatha edluliselwe nokulawula amandla.

prehistory

broadband yeselula, ogxile iphakethe ukuthumela idatha ubuchwepheshe ngesivinini phezu HSPA ejwayelekile, sesibe kwamukelwa kabanzi abasebenzisi amanethiwekhi amaselula. Nokho, kumelwe siqhubeke ukwenza ngcono kwezidingo zabo, isibonelo, ukusebenzisa ukwanda idatha isivinini translation, ukunciphisa ukubambezeleka futhi ukwandisa jikelele amandla inethiwekhi kanye nezidingo umsebenzisi amasevisi wemiyalezo enjalo njalo liphuma. Nge le njongo, futhi kwatholwa sebhithi radiointrfeysov HSPA Evolution ne-LTE 3GPP Consortium.

Umahluko omkhulu ezinguqulweni ngaphambili

LTE inethiwekhi ejwayelekile ihlukile izici ngaphambilini athuthukile 3G uhlelo ngcono, kuhlanganise ijubane esiphezulu lapho ukudluliswa kolwazi - engaphezu kuka-300 megabits ngesekhondi ukubambezeleka ukudluliswa iphakethe ngeke idlule 10 millisecond nekghono Spectral lalilikhulu kakhulu kunalokho. Ukwakhiwa LTE kungaba kwenziwe entsha imvamisa bands, njengasezulwini opharetha ekhona kanye.

Lokhu umsakazo ibekwe njengoba isixazululo, lapho opharetha ngeke kancane kancane amazinga uhlelo lokho okushodayo ekudleni ngaleso sikhathi, kuba 3GPP futhi 3GPP2. Intuthuko lokhu esibonakalayo - lena ngempela yisinyathelo esibalulekile ekufezeni kumiswa ejwayelekile IMT-Advanced 4G amanethiwekhi, ukuthi isizukulwane esisha. Empeleni, e-LTE esifakiwe kakade iqukethe izici eziningi ukuthi base ayekuhlosile ngoba 4G izinhlelo.

Isimiso ukuhlela kokusetshenziswa kubonwa umsakazo

ukuxhumana Radio has isici sobuntu esakhiwa ngo yokuthi izinga ishaneli yomsakazo akuyona njalo ngesikhathi nendawo futhi imvamisa nasekuthengeni. Lapha kufanele kusho ukuthi imingcele zokuxhumana ziyashintsha kuqhathaniswa ngokushesha ngenxa multipath esiphelweni. Ukuze kulondolozwe izinga njalo exchange of ulwazi ishaneli yomsakazo, oluvame ukusetshenziswa ngezindlela eziningi ukunciphisa lezo zinguquko, okungukuthi - amasu ahlukahlukene sokudlulisa ukwehluka. Ngesikhathi esifanayo ngo inqubo yokudlulisela amaphakethe abasebenzisi ulwazi abakwazi njalo ukuqaphela iyehla iyenyuka esifushane izinga kancane. LTE Imodi yenethiwekhi eqala njengoba isimiso jikelele sisekhona ukufinyelela umsakazo, futhi ukusetshenziswa izinguquko ngokushesha izinga ishaneli yomsakazo ukuze wandise ekusetshenzisweni umsakazo usizo olutholakalayo esigabeni isikhathi ngasinye phuzu. Lokhu ukusebenza imvamisa nesikhathi izizinda ngu OFDM ukufinyelela umsakazo ubuchwepheshe.

LTE idivayisi inethiwekhi

Hlobo luni uhlelo kungenziwa kuphela waqonda ukuqonda ukuthi indlela ihlelwe. Kusekelwe ezivamile OFDM ubuchwepheshe, okusho nokudluliswa kwemininingwane yonkana subcarriers narrowband amaningi. Ukusetshenziswa yokugcina ngokuhlanganyela isiqalo eyindilinga ikuvumela ukuba wenze uxhumano ngesisekelo OFDM ukumelana ukuhlakazwa yesikhashana nemingcele ishaneli yomsakazo, futhi ivumela cishe asikho isidingo equalizers eziyinkimbinkimbi ohlangothini umamukeli. Lesi simo iyasiza inhlangano isiteshi ukwehla, njengoba kulokhu kungenzeka kube lula ukusebenza owamukelayo isignali nobuningi main, ngaleyo ndlela kuncishiswe izindleko idivayisi esibulalayo, namandla sokudliwa kubo. Futhi lokhu kubaluleke kakhulu lapho sisebenzisa i inethiwekhi ye-4G LTE ne ukudluliswa ikumodi sendikimba amaningi.

isiteshi uplink, lapho amandla Babechichima kuyinto aphansi ukwedlula e-downlink idinga ukufakwa saziso ku-eyonga amandla ulwazi operation ukudluliswa indlela Ukusabalala esiphezulu, ukunciphisa amandla ukusetshenziswa idivaysi eyamukelayo, kanye nezindleko zayo. Uphenyo kwaholela yokuthi manje isiteshi uplink LTE isebenzisa ulwazi olulodwa imvamisa ubuchwepheshe ukusakaza ngesimo OFDM nge ukuhlakazeka imithetho efanele ngokuqhubekayo Fourier uguqule. isixazululo enjalo ivumela isilinganiso sakugcina isilinganiso kanye esiphezulu amandla ezingeni ngokuziqhathanisa ukushintshashintsha kwezwi bendabuko, okungaba ngcono ukusebenza kahle futhi kube lula ukwakhiwa amadivaysi esigungwini.

Isisetshenziswa eziyisisekelo ezisetshenziswa ekudluliseni ulwazi ngokuhambisana ODFM ubuchwepheshe kungenziwa wabonisa ngendlela isikhathi-imvamisa inethiwekhi, okuhambelana iqoqo OFDM izimpawu subcarriers esikhathini futhi imvamisa izizinda. LTE Imodi yenethiwekhi izitshela ukuthi njengoba idatha eyinhloko isici ezimbili isisetshenziswa block lisetshenziswe lapha, okuyinto zivumelana ibhendi yokuvama 180 kHz futhi isikhawu sesikhathi ngokuhlola elilodwa amasekhondi amancane. A ezahlukene ngesivinini yokudlulisela idatha kungenziwa igcwaliseke ngokuhlanganisa izinsiza imvamisa, ukulungiselelwa zokuxhumana ipharamitha kuhlanganise ikhodi izinga nokuguquguquka kwezwi oda Ukukhetha.

izici lobuchwepheshe

Uma sicabangela inethiwekhi LTE, ukuthi kuyini, kuyokhanya emva abanye incazelo. Ukuze kuzuzwe okusezingeni eliphezulu asethwe for esibonakalayo emoyeni we inethiwekhi, onjiniyela yalo ehleliwe amaphuzu amaningana kunalokho ezibalulekile kanye nezici. Okulandelayo uzobe kuchazwe, ngalinye elikwazi abe inkomba eningiliziwe umthelela wabo ezibaluleke kangaka ikhono inethiwekhi Ukusabalala endaweni, isikhathi ukubambezeleka kanye nesivinini ukudluliswa kwedatha.

Ukuvumelana nezimo ukusetshenziswa bohlu umsakazo

Umthetho, okuyinto usebenza endaweni ethize ngokwebalazwe, kuthinta indlela yezokuxhumana mobile uzobe ihlelwe. Okungukuthi, ebekiwe bohlu umsakazo esabelwe imvamisa ehlukene ububanzi bands ayibhangqiwe noma abhanqiwe ka nobubanzi ezahlukene. Ukuvumelana nezimo - lena enye yezinzuzo ezinkulu LTE umsakazo spectrum, okuvumela ukusetshenziswa kwayo ezimweni ezahlukene. LTE inethiwekhi izakhiwo ivumela nje kuphela usebenze ezahlukene imvamisa amabanga, kodwa ispolzovat imvamisa bands kokuba nobubanzi sihluke 1.25 kuya ku-20 MHz. Ngaphezu kwalokho, isimiso esinjalo angafeza ukusebenza ngababili ayibhangqiwe imvamisa bands, ukugcina isikhathi kanye nokuvama Duplex ngokulandelana.

Uma sikhuluma amadivayisi ukuphela, lapho ispolzovanenii abhanqiwe imvamisa bands iyunithi ongasebenza kwimodi noma isigamu-Duplex ngokugcwele Duplex. Imodi yesibili, okuyinto eyenziwa ukudluliswa esibulalayo futhi yokwamukela idatha ngezinye izikhathi ezihlukahlukene nangezikhathi okungavamile amaza ezahlukene ikhange ngoba kakhulu kunciphisa izidingo izici embukisweni isihlungi Duplex. Ngenxa yalesi kungenzeka ukunciphisa izindleko amadivayisi esigungwini. Ngaphezu kwalokho, kukhona ithuba ukwethulwa abhanqiwe imvamisa bands nge Duplex Isikhala encane. It kuvela ukuthi LTE ukuxhumana mobile inethiwekhi zingahlelwa e cishe kunoma iyiphi ukusatshalaliswa uhlu lokuvama.

Inkinga kuphela ekusungulweni kobuchwepheshe bokuthuthukisa umsakazo, esinikela isicelo nezimo radispektra - ukwenza idivayisi zokuxhumana ehambisanayo. Nale inhloso LTE ubuchwepheshe lwenteke ezifanayo Uhlaka isakhiwo esimweni imvamisa amaviyo nobubanzi ezahlukene kanye ezahlukene Duplex izindlela.

Multi-antenna idatha ukusakaza

Ukusetshenziswa multi-antenna ukusakaza ku mobile zokuxhumana kungaba ncono kusebenta kwato, futhi ukuthuthukisa amakhono abo ngokuya nokunakekelwa kwamakhasimende. Lokunameka LTE inethiwekhi kuhilela ukusetshenziswa ezimbili multi-antenna izindlela yokudlulisela: ukwehluka futhi multi-threaded, njengoba icala okuyisipesheli ivelele kumiswa ungumthombo ongumngcingo antenna uvumelanise. Imininingwane kungefani kungase kubhekwe njengento indlela nokulingana ezingeni isignali lovela antenna ezimbili, okuyinto ugwema ofaka ku amasignali ezijulile-level atholakale antenna ngayinye.

Ungabona okuningi inethiwekhi LTE: kuyini futhi lisebenzisa indlela zonke lezi izindlela? Indlela ukwehluka ukudluliswa lapha kusekelwe ngekwendzawo imvamisa wekhodi emabhuloki idatha, okuyinto kulekelelwa isikhathi ukwehluka kuya shift imvamisa ekusebenziseni antenna ezine kanyekanye. Dlulisa ukwehluka ngokuvamile esetshenziselwa downlink wabelane iziteshi lapho akwenzeki ukusebenzisa umsebenzi ukuhlela kuye nesimo isiteshi zokuxhumana. Ngakho Diversity ukudluliswa ingasetshenziswa ngokudlulisela idatha yomsebenzisi, isib, VoIP traffic. Ngenxa umfutho iphansana lokhu traffic awukwazi bathethelele phezulu ezengeziwe okuhlotshaniswa umsebenzi ukuhlela okukhulunywe ngaye ekuqaleni. Ngenxa ukuhlukahluka ukudluliswa kwedatha kungenzeka ukwandisa lo engaba amaseli kanye namandla inethiwekhi.

ukudluliswa Multithreaded ukudlulisa ngesikhathi esisodwa eziningi ulwazi ageleza kusiteshi umsakazo owodwa ukusebenzisa amaningi ukuthola futhi udlulise antenna ku apharathasi esibulalayo futhi inethiwekhi base station, ngokulandelana. Lokhu kakhulu kwandisa esiphezulu idatha izinga kokusakaza. Ngokwesibonelo, uma idivayisi esibulalayo ifakwe antenna ezine kanye nenombolo iyatholakala kwi idonsa khona, kuba real kuba ukudluliswa kanyekanye kusiteshi umsakazo omunye ukusakaza ezine idatha, okuvumela ukuba empeleni wenze komkhawulokudonsa ngaphezulu ke kane.

Uma usebenzisa inethiwekhi nge umsebenzi encane noma amaseli encane, sibonga multi-Ukusakaza sizokwazi sifinyelele komkhawulokudonsa siphakeme ngokwanele ukuze iziteshi zomsakazo, kanye ekusetshenzisweni umsakazo imithombo. Uma kukhona amaseli esikhulu ngezinga eliphezulu ukushuba umthwalo, ikhwalithi isiteshi ayikuvumeli ukuxhaphaza kwimodi multipotoka. Kulokhu, izinga isignali kungathuthukiswa uma ukusetshenziswa amaningi sokudlulisa antenna ukwakha ugongolo ewumngcingo ngokudlulisa idatha ku ukusakaza olulodwa.

Uma sicabangela inethiwekhi LTE - ke wambamba ukufeza ngekhono elingcono - ke kuwufanele ukuphetha ngokuthi umsebenzi izinga ezimweni yokusebenza ahlukahlukene, lobu buchwepheshe luyasetshenziswa oluhambelana multi-ekusakazeni ukudluliswa, okuyinto ikuvumela ukuba njalo ulungise inani ukusakaza ngocansi kanyekanye, ngokuhambisana oshintshashintsha isixhumanisi isimo. Nge esesimweni esihle isiteshi kungaba kwenziwe kanyekanye adlulisa kuze kube idatha ukusakaza ezine ezingasisiza sifinyelele amazinga okudluliseka-300 megabits ngomzuzwana ngesikhathi komkhawulokudonsa imvamisa megahertz 20.

Uma isimo siteshi asikho evumayo ngakho, ukudluliswa senziwa ukusakaza ambalwa. Kulesi simo, antenna ingasetshenziswa ukwakha ewumngcingo ugongolo iphethini, okwandisa izinga lokusesha lilonke reception, okwagcina kuholela ukwandisa umthamo uhlelo nasekwandeni komsebenzi indawo yesevisi. Ukuqinisekisa i Ukuhlanganisa endaweni ebanzi noma ukudlulisa idatha ngesivinini, kungenzeka ukuba adlulisele ukusakaza okukodwa ngedatha ugodo ewumngcingo, noma ukusebenzisa idatha ukusakaza esilinganayo iziteshi ezivamile.

Mshini okuzivumelanisa futhi ukuhlela isiteshi zokuxhumana

Umgomo we operation amanethiwekhi LTE isikisela ukuthi ukuhlela kuzosho ukusatshalaliswa inethiwekhi imithombo phakathi abasebenzisi idatha. Lapha inikeza ukuhlela ashukumisayo e downlink kanye uplink iziteshi. LTE inethiwekhi eRussia usethe okwamanje ukuze silinganise imigudu zokuxhumana kanye kusebenta jikelele ohlelweni lonke.

LTE umsakazo esibonakalayo kuhilela ukuqaliswa ukuhlela imisebenzi, kuye ngokuthi isimo isiteshi zokuxhumana. Nge ivumela ukudluliswa kwedatha ngesivinini, okuyinto ibangelwa ngokusebenzisa ephakeme ukushintshashintsha kwezwi ukuze, ukudluliswa kwe-ulwazi olwengeziwe nemifudlana, ukunciphisa izinga kwesiteshi esephepheni, kanye ukunciphisa isibalo uphinda ukusakazwa. Ukuze wenze lokhu kuhilela imvamisa nesikhathi izinsiza zinezikhathi izimo kahle ngokuxhumana. It kuvela ukuthi ukudluliswa kwanoma iyiphi imali inikezwe of idatha kwenziwa esikhathini esifushane yesikhathi.

LTE inethiwekhi eRussia, njengoba kwamanye amazwe, zakhiwa ukuze amasevisi womgwaqo, iziphi elalihlala wokudlilisela amaphakethe nge payloads elincane ngemva okufanayo zinkathi, kungabangela isidingo ukuze wandise ivolumu zokubonisa lomthamo iyadingeka ukuze ukuhlela ashukumisayo. Kungase idlule ngisho inani Imininingwane ngocansi ngumsebenzisi. Yingakho kukhona into okuthiwa ukuhlela kazibuthe inethiwekhi LTE. Okungukuthi, kuba sobala, uma sithi umsebenzisi ukhetha omsakazo ezinsiza ukudluliswa inombolo letsite, wase sub-ozimele.

Ngenxa indlela yokufunda ukuphila nesimo esithile kungenzeka ukuba "ngawakhamela out konke okusemandleni" kusukela isiteshi ukusebenza ashukumisayo. It ikuvumela ukuba ukhethe isiteshi esephepheni uhlelo nokuguquguquka kwezwi ngaphakathi accordance nga babe izimo libhekene LTE kwenethiwekhi. Lokho-ke Kungaqondakala uma ukusho ukuthi umsebenzi wakhe kuthinta izinga idatha okusakaza, kanye amathuba isiteshi noma yimaphi amaphutha.

Amandla e-uplink nekulawulwa

Lesi sici siphathelene ekuphathweni ezingeni amandla Babechichima ngu terminals, ukwandisa umthamo inethiwekhi, ukuthuthukisa izinga lokuxhumana, ukwenza Ukusabalala endaweni ngaphezulu ukunciphisa energy ukusetshenziswa. Kute kufezeke letinhloso, ukulawula amandla izindlela bavame ukukhulisa izinga ewusizo isignali okufakwayo ngenkathi ekunciphiseni ukuphazamiseka.

LTE inethiwekhi "Beeline" kuhlanganise nezinye izinkulumo zisikisela ukuthi amasignali e-uplink kukhona orthogonal, okungukuthi phakathi kwabasebenzisi iseli efanayo kufanele kube khona ukuphazamiseka mutual, okungenani, lokhu kusebenza izimo ezikahle zokuxhumana. Izinga umsindo adalwe abasebenzisi e amaseli aseduze, incike lapho ukuphela likhipha, ukuthi ingabe attenuates indlela isignali endleleni ingqamuzana. LTE inethiwekhi "megaphone" kuhlelwe ngendlela efanayo. Kuzoba inembile inkulumo ethi: sisondelene ukuphela kuseli elingumakhelwane, ephakeme kunomsindo, yena kudala kuwo. Terminals, abase-ibanga elithileko kusuka cell elingumakhelwane bangadlulisela amasignali esithe xaxa uma ziqhathaniswa ezikhumulweni elise nalo iseduze.

Ngenxa orthogonality signal ku-uplink kungenzeka multiplexed amasignali kusuka amandla ezahlukene terminals nesiteshi esifanayo kuseli efanayo. Lokhu kusho ukuthi asikho isidingo isinxephezeliso isignali Ukuvutha ezingavela ngenxa multipath esiphelweni ngamagagasi omsakazo, futhi ingasetshenziswa ukwandisa izinga idatha ukusakaza usebenzisa lithathelwe futhi ukuhlela izindlela iziteshi zokuxhumana.

zikusakaza idatha

Cishe noma yimuphi uhlelo lokuxhumana, ne-LTE inethiwekhi e-Ukraine azihlukile ngezikhathi ezithile senza amaphutha kule nqubo ye ukuthumela idatha, isibonelo, ngenxa eyobonisa lantambama, ukuphazamiseka noma umsindo. Ukuvikelwa Iphutha olunikezwa izindlela we retransmission izingxenye elahlekile noma lonakele ulwazi ukuba kugada ukuqinisekisa okusezingeni eliphezulu zokuxhumana izinga. Isisetshenziswa somsakazo isetshenziswa kabanzi ngendlela enomqondo uma olandelwayo idatha retransmission okuhlelwe kahle. Ukusebenzisa high speed umoya esibonakalayo ophelele, LTE technology has ngamandla ngempumelelo ezimbili-level idatha uhlelo edluliselwe nokobana Hybrid ARQ. It libhekene phezulu encane edingekayo ngempendulo futhi idatha retransmission, kulekelelwa abakhethayo uphinda olandelwayo we enokwethenjelwa.

HARQ Iziphakamiso eziyisisekelo wanikeza ethola idivayisi Imininingwane eziphindaphindekayo, okuyinto umnikeza ithuba alungise noma yimaphi amaphutha ethize. Retransmission HARQ olandelwayo kuholela ekwakhekeni ulwazi olungeziwe komsebenzi, okungase kudingeke esimweni lapho ngenxa yesiphosiso kwakungelona retransmission ngokwanele. Retransmission amaphakethe ukuthi awuzange lidlule ukulungiswa HARQ olandelwayo wenziwa ngokusebenzisa iphrothokholi ARQ. LTE inethiwekhi ku umsebenzi iPhone ngokuhambisana nezimiso ngenhla.

Lokhu Isixazululo kwenza kube nokwenzeka ukuze kuqinisekwe ukuthi ubuncane Ukulibaziseka kokusakaza amaphakethe nge phezulu phansi, zokuxhumana nokwethenjelwa nge yibhange. HARQ protocol uvumela ukuthola alungise iningi amaphutha, okuholela ukusetshenziswa kunalokho ezingavamile ARQ olandelwayo, ngoba lihlotshaniswa phezulu eside, kanye nokwanda ukubambezeleka amaphakethe ukusakaza.

Isiteshi base iyona engeyokuqala ekupheleni, olusekela zombili lezi yezifiso, ukuhlinzeka ubuhlobo obuseduze amazinga yalezi yezifiso ezimbili. Phakathi izinzuzo ezihlukahlukene lokhu izakhiwo kungenziwa ngokuthi ngesivinini ukuqeda amaphutha ukuthi ahlale emva kokusebenza HARQ, kanye nenani ukulungiswa kolwazi ngocansi ngokusebenzisa olandelwayo ARQ.

I-LTE umsakazo esibonakalayo has ukusebenza high, sibonga izingxenye zalo eziyinhloko. Ukuvumelana nezimo ivumela ukusetshenziswa umsakazo emoyeni esibonakalayo esebenzayo kunoma iyiphi etholakalayo imvamisa nsiza. LTE ubuchwepheshe inikeza eziningi izici ukuqinisekisa ukuthi isicelo ngempumelelo ukuxhumana imvelo oguqukayo. Kuye isimo isiteshi, umsebenzi ukuhlela Inikeza abasebenzisi kwemibhalo engcono. Isicelo multi-antenna ubuchwepheshe kunciphisa isignali lantambama kanye lo mshini isiteshi lithathelwe angasebenzisa izindlela esephepheni nokuguquguquka kwezwi, eqinisekisa ezimweni ethile yokuxhumana elilungile izinga.