802.11a/b/g/n/ac Uphuhliso kunye nokwahluka

802.11a/b/g/n/ac Uphuhliso kunye noKwahluka
Ukususela oko kwakhutshwa i-Wi Fi okokuqala kubathengi ngo-1997, umgangatho we-Wi Fi ubusoloko utshintsha, udla ngokwandisa isantya kunye nokwanda kokugubungela. Njengoko imisebenzi yongezwa kumgangatho wokuqala we-IEEE 802.11, yahlaziywa ngokulungiswa kwayo (802.11b, 802.11g, njl.njl.)

802.11b 2.4GHz
I-802.11b isebenzisa i-frequency efanayo ye-2.4 GHz kunye nomgangatho wokuqala we-802.11. Ixhasa isantya esiphezulu sethiyori se-11 Mbps kunye noluhlu olufikelela kwi-150 feet. Izinto ze-802.11b zixabiso eliphantsi, kodwa lo mgangatho unesantya esiphezulu nesicothayo phakathi kwayo yonke imigangatho ye-802.11. Kwaye ngenxa ye-802.11b esebenza kwi-2.4 GHz, izixhobo zasekhaya okanye ezinye iinethiwekhi ze-2.4 GHz Wi-Fi zinokubangela ukuphazamiseka.

802.11a 5GHz OFDM
Inguqulelo ehlaziyiweyo ethi “a” yalo mgangatho ikhutshwa ngaxeshanye ne-802.11b. Ingenisa ubuchwepheshe obuntsonkothileyo obubizwa ngokuba yi-OFDM (Orthogonal Frequency Division Multiplexing) bokuvelisa iimpawu ezingenazingcingo. I-802.11a inika ezinye iingenelo ngaphezu kwe-802.11b: isebenza kwibhendi ye-frequency ye-5 GHz engaxineneyo kwaye ngenxa yoko ayichaphazeleki lula. Kwaye i-bandwidth yayo iphezulu kakhulu kune-802.11b, enomlinganiselo ophezulu we-54 Mbps.
Kusenokwenzeka ukuba awuzange udibane nezixhobo ezininzi ze-802.11a okanye ii-routers. Oku kungenxa yokuba izixhobo ze-802.11b zitshiphu kwaye ziya zithandwa kakhulu kwimarike yabathengi. I-802.11a isetyenziswa kakhulu kwizicelo zoshishino.

802.11g 2.4GHz OFDM
Umgangatho we-802.11g usebenzisa ubuchwepheshe obufanayo be-OFDM njenge-802.11a. Njenge-802.11a, ixhasa isantya esiphezulu sethiyori se-54 Mbps. Nangona kunjalo, njenge-802.11b, isebenza kwiifrikhwensi ze-2.4 GHz ezixineneyo (kwaye ngenxa yoko inengxaki yokuphazamiseka efanayo neye-802.11b). I-802.11g iyahambelana nezixhobo ze-802.11b ngasemva: izixhobo ze-802.11b zinokuqhagamshela kwiindawo zokufikelela ze-802.11g (kodwa ngesantya se-802.11b).
Nge-802.11g, abathengi benze inkqubela phambili enkulu kwisantya kunye nokugubungela i-Wi-Fi. Okwangoku, xa kuthelekiswa nezizukulwana zangaphambili zeemveliso, ii-routers ezingenazingcingo zabathengi ziya zisiba ngcono ngakumbi, ngamandla aphezulu kunye nokugubungela okungcono.

I-802.11n (i-Wi Fi 4) i-2.4/5GHz MIMO
Ngomgangatho we-802.11n, i-Wi Fi iye yakhawuleza kwaye yathembeka ngakumbi. Ixhasa izinga eliphezulu lokudlulisela i-300 Mbps (ukuya kuthi ga kwi-450 Mbps xa usebenzisa ii-antenna ezintathu). I-802.11n isebenzisa i-MIMO (Multiple Input Multiple Output), apho abathumeli/abamkeli abaninzi basebenza ngaxeshanye kwelinye okanye omabini amacala ekhonkco. Oku kunokunyusa kakhulu idatha ngaphandle kokufuna i-bandwidth ephezulu okanye amandla okudlulisela. I-802.11n inokusebenza kwiibhendi zefrikhwensi ze-2.4 GHz kunye ne-5 GHz.

802.11ac (Wi Fi 5) 5GHz MU-MIMO
I-802.11ac inyusa i-WiFi, ngesantya esiqala kwi-433 Mbps ukuya kwi-gigabits ezininzi ngomzuzwana. Ukuze kufezekiswe oku kusebenza, i-802.11ac isebenza kuphela kwi-frequency band ye-5 GHz, ixhasa ukuya kuthi ga kwi-spatial streams ezisibhozo (xa kuthelekiswa ne-streams ezine ze-802.11n), iphinda kabini ububanzi betshaneli ukuya kwi-80 MHz, kwaye isebenzisa iteknoloji ebizwa ngokuba yi-beamforming. Nge-beamforming, ii-antenna zinokudlulisela imiqondiso yerediyo, ngoko ke zikhomba ngqo kwizixhobo ezithile.

Olunye uphuculo olubalulekileyo lwe-802.11ac yiMulti User (MU-MIMO). Nangona i-MIMO iqondisa imijelo emininzi kumthengi omnye, i-MU-MIMO inokuqondisa imijelo yendawo ngaxeshanye kubathengi abaninzi. Nangona i-MU-MIMO inganyusi isantya salo naliphi na iklayenti, inokuphucula ukuhanjiswa kwedatha iyonke kwinethiwekhi yonke.
Njengoko ubona, ukusebenza kwe-WiFi kuyaqhubeka nokukhula, ngesantya esinokubakho kunye nokusebenza kusondela kwisantya esineentambo.

I-Wi-Fi 6 ye-802.11ax
Ngowama-2018, iWiFi Alliance yathatha amanyathelo okwenza kube lula ukuqonda amagama asemgangathweni eWiFi. Baza kutshintsha umgangatho ozayo we-802.11ax ube yiWiFi6.

I-Wi Fi 6, iphi i-6?
Izalathisi ezahlukeneyo zokusebenza kwe-Wi Fi ziquka umgama wokudluliselwa, izinga lokudluliselwa, umthamo wenethiwekhi, kunye nobomi bebhetri. Ngophuhliso lwetekhnoloji kunye namaxesha, iimfuno zabantu zesantya kunye ne-bandwidth ziya ziphakama ngakumbi.
Kukho uthotho lweengxaki kwiinethiwekhi zendabuko ze-Wi-Fi, ezifana nokuxinana kwenethiwekhi, ukugutyungelwa okuncinci, kunye nesidingo sokutshintsha ii-SSID rhoqo.
Kodwa i-Wi Fi 6 iza kuzisa utshintsho olutsha: iphucula ukusetyenziswa kwamandla kunye nokukwazi ukugubungela izixhobo, ixhasa ukuhambelana kwesantya esiphezulu kwabasebenzisi abaninzi, kwaye inokubonisa ukusebenza okungcono kwiimeko ezifuna abasebenzisi abaninzi, ngelixa ikwazisa umgama omde wokudlulisela kunye namazinga aphezulu okudlulisela.
Lilonke, xa kuthelekiswa nezinye zangaphambili, inzuzo yeWi Fi 6 "yi-dual high kunye ne-dual low":
Isantya esiphezulu: Ngenxa yokwaziswa kwetekhnoloji ezifana ne-uplink MU-MIMO, i-1024QAM modulation, kunye ne-8 * 8MIMO, isantya esiphezulu se-Wi Fi 6 sinokufikelela kwi-9.6Gbps, ekuthiwa sifana nesantya sokubetha.
Ukufikelela okuphezulu: Eyona nto ibalulekileyo ekuphuculweni kwe-Wi Fi 6 kukunciphisa ukuxinana nokuvumela izixhobo ezininzi ukuba ziqhagamshelane nenethiwekhi. Okwangoku, i-Wi Fi 5 inokunxibelelana nezixhobo ezine ngaxeshanye, ngelixa i-Wi Fi 6 iza kuvumela unxibelelwano olufikelela kwizixhobo ezininzi ngaxeshanye. I-Wi Fi 6 ikwasebenzisa i-OFDMA (i-Orthogonal frequency-division multiple access) kunye netekhnoloji ye-multi-channel signal beamforming evela kwi-5G ukuphucula ukusebenza kakuhle kwe-Spectral kunye nomthamo wenethiwekhi ngokwahlukeneyo.
Ukulibaziseka okuphantsi: Ngokusebenzisa ubuchwepheshe obufana ne-OFDMA kunye ne-SpatialReuse, i-Wi Fi 6 ivumela abasebenzisi abaninzi ukuba badlulisele umyalezo ngaxeshanye ngexesha ngalinye, isusa isidingo sokuma emgceni nokulinda, inciphisa ukhuphiswano, iphucula ukusebenza kakuhle, kwaye inciphisa ukulibaziseka. Ukusuka kwi-30ms kwi-Wi Fi 5 ukuya kwi-20ms, kunye nokunciphisa ukulibaziseka okuphakathi kwe-33%.
Ukusetyenziswa kwamandla aphantsi: I-TWT, enye iteknoloji entsha kwi-Wi Fi 6, ivumela i-AP ukuba ixoxisane nonxibelelwano nee-terminals, inciphisa ixesha elifunekayo ukugcina uthumelo kunye nokukhangela imiqondiso. Oku kuthetha ukunciphisa ukusetyenziswa kwebhetri kunye nokuphucula ubomi bebhetri, okubangela ukwehla kwama-30% ekusebenziseni amandla kwi-terminal.

Ukusukela ngo-2012 | Nika iikhompyutha zoshishino ezenzelwe wena kubathengi behlabathi!