Boka rinoshanda rakatanga kushanda pane yakajairwa kumashure muna 2014 uye parizvino riri kushanda pakunyorwa 3.0. Izvo zvakati siyanei nezvizvarwa zvakapfuura zve802.11 zviyero, nekuti ipapo basa rese rakaitwa muzvinyorwa zviviri. Izvi zvinoitika nekuda kwenhamba yakakura yekuchinja kwakarongwa kwakaoma, izvo zvinoda kutsanangurwa uye kwakaoma kuenderana kuyedzwa. Dambudziko rekutanga rechikwata raive rekuvandudza spectral performance kuti iwedzere huwandu hweWLANs ine huwandu hwakanyanya hwevanyoreri zviteshi nenzvimbo dzekuwana. Iwo madhiraivha makuru ekusimudzira chiyero aive: kuwedzera kwenhamba yevanyoreri venhare, nhepfenyuro yehupenyu pasocial network (kusimbisa pakurodha traffic) uye, hongu, IoT.
Schematically, zvitsva zvinotaridzika seizvi:
MIMO 8x8, mamwe nzizi dzepamhepo
Pachave nerutsigiro rweMIMO 8x8, kusvika ku8SS (Spatial Streams). Iyo 802.11ac standard yakatsanangurawo tsigiro ye8 SS mudzidziso, asi mukuita, 802.11ac "wave 2" nzvimbo dzekuwana dzakaganhurirwa kutsigira 4 spatial hova. Saizvozvo, nzvimbo dzekuwana dzinotsigira MIMO 8x8 dzichakwanisa kushandira panguva imwe chete kusvika 8 1x1 vatengi, vana 2x2 vatengi, nezvimwe.
MU-MIMO DL/UL (Multi-User MIMO Downlink/Uplink)
Tsigiro yenguva imwe chete yevazhinji modhi yekurodha uye kurodha zviteshi. Iko kugona kwekukwikwidza panguva imwe chete kune yekukwirisa chiteshi, kuisa mapoka ese ari maviri emazuva uye ekudzora mafuremu anozodzikisa zvakanyanya "pamusoro", izvo zvinozotungamira mukuwedzera kwekubuda uye kudzikira munguva yekupindura.
Yakareba OFDM chiratidzo
OFDM yanga ichishanda mu802.11a/g/n/ac zviyero kwe~makore makumi maviri pasina shanduko. Zvinoenderana nechiyero, chiteshi chine hupamhi hwe20MGz ine 20 subcarriers yakaparadzana kubva kune imwe neimwe ine nguva ye64 kHz (312,5MHz)./64) Sezvo iyo semiconductor indasitiri yafambira mberi zvakanyanya panguva ino, 802.11x inopa 4-kupeta kuwedzera kune subcarriers kusvika 256, nepakati pakati pevatakuri ve78,125 kHz. Kureba kwechiratidzo cheOFDM (nguva) inopesana nekuenzanisa, uye maererano naizvozvo ichawedzerawo ne 4 nguva kubva 3,2 ΞΌs kusvika 12,8 ΞΌs. Kuvandudzwa uku kuchawedzera kushanda uye kuvimbika kwekufambiswa kwemashoko, kunyanya mu "kunze" WLAN.
Yakawedzerwa Range
Hutsva hutsva hwenguva dzekudzivirira pakati pemafuremu dzawedzerwa, dzinogona kuenzana ne1,6 Β΅s uye 3,2 Β΅s dze "kunze" WLAN; ye "mukati" nguva inosiiwa pa0,8 Β΅s. New packet fomati ine yakavimbika (refu) preamble. Zvese zviri pamusoro zvinokutendera iwe kuti ukwire kusvika ku4-kupeta kuwedzera kwekumhanya kwekubatanidza pamucheto wetiweki.
OFDMA DL/UL (Orthogonal Frequency Division Multiple Access)
Imwe yekuchinja kukuru kuunzwa kweOFDMA pachinzvimbo cheOFDM. OFDMA tekinoroji inoshandiswa muLTE network uye yakaratidza kuve inoshanda zvakanyanya. Musiyano ndewekuti kana uchitumira muOFDM, iyo frequency chiteshi inogarwa uye kudzamara kutapurirana kwapera, mutengi anotevera haakwanise kutora frequency sosi. MuOFDMA, dambudziko iri rinogadziriswa nekukamura chiteshi kuita subchannels ehupamhi hwakasiyana, iyo inonzi RU (Resource Units). Mukuita, izvi zvinoreva kuti 256 subcarriers ye20MHz chiteshi inogona kukamurwa kuita RUs ye26 subcarriers. Imwe neimwe RU inogona kupihwa yayo MCS coding scheme, pamwe nekufambisa simba.
Pakazere, izvi zvinounza kuwedzera kwakakosha kwetiweki huwandu hwese, pamwe nekubuda kwemutengi wega wega.
1024 QAM
Yakawedzera nyowani MCS (Modulation uye Coding Sets) 10 uye 11 ye1024-QAM modulation. Ndiko kuti, ikozvino hunhu muhurongwa uhu huchatakura gumi mabhiti eruzivo, uye uku kuwedzera kwe10% zvichienzaniswa ne25bit mu8-QAM.
TWT (Target Wake Time) - "Up Link resource kuronga"
Muchina wekuchengetedza simba wakazviratidza mune 802.11ah chiyero uye ikozvino yakagadziridzwa kuita 802.11ax. TWT inobvumira mapoinzi ekuwana kuti audze vatengi nguva yekupinda-yekuchengetedza simba modhi uye inopa hurongwa hwenguva yekumuka kuti ugamuchire kana kutumira ruzivo. Idzi inguva pfupi, asi kugona kurara kwenguva pfupi kuchaita mutsauko mukuru kuhupenyu hwebhatiri. Kuderedza "kukakavadzana" uye kudhumhana pakati pevatengi kuchawedzera nguva inoshandiswa mukuchengetedza simba. Zvichienderana nerudzi rwemotokari, kuvandudzwa kwesimba rekushandisa kunogona kubva pa65% kusvika 95% (maererano neBroadcom bvunzo). Kune zvishandiso zveIoT, tsigiro yeTWT yakakosha.
BSS Ruvara - Spatial Reuse
Kuti uwedzere huwandu hweiyo yepamusoro-density WLAN network, zvinodikanwa kuwedzera kuwanda kwekushandisazve chiteshi chekushandisa. Kuti uderedze pesvedzero yevavakidzani maBSS anoshanda pachiteshi chimwe chete, zvinokurudzirwa kumaka ne "color-bit". Izvi zvinokutendera kuti ugadzirise zvine simba iyo CCA (yakajeka chiteshi chekuongorora) kunzwa uye transmitter simba. Kugona kwetiweki kuchawedzera nekuda kwekumisikidzwa kwechirongwa chechiteshi, nepo kupindira kuripo kuchave nekukanganisa kusarudzwa kweMCS.
Nekuda kwekuvandudzwa kuri kuuya kwezviyero zvekuchengetedza ku , havasi vese vachakwanisa kugadzirisa nyaya dzekuchengetedza nesoftware yakapfava, saka Extreme Networks ichaunza nzvimbo dzekuwana nerutsigiro rwehardware ye2018ax uye WPA802.11 muchikamu chechina che3.
Zvimwe pamusoro .
Source: www.habr.com