1. Basic Concepts
Dangane da ainihin fasahar LTE (Juyin Juyin Halitta na Dogon Lokaci), tsarin 5G NR yana ɗaukar wasu sabbin fasahohi da gine-gine.5G NR ba wai kawai ya gaji OFDMA (Orthogonal Frequency-Division Multiple Access) da FC-FDMA na LTE ba amma ya gaji fasahar antenna da yawa na LTE.Gudun MIMO ya fi LTE.A cikin daidaitawa, MIMO tana goyan bayan zaɓin daidaitacce na QPSK (Orthogonal Frequency-Division Multiple Access), 16QAM (16 multi-level quadrature amplitude modulation), 64QAM (64 multi-level quadrature amplitude modulation), da 256 QAM (256 multi-level quadrature amplitude amplitude) modulation).
Tsarin NR, kamar LTE, na iya sassauƙa keɓance lokaci da mitar a cikin bandwidth ta hanyar rarrabuwar rabe-raben mitar da rarrabuwar lokaci.Amma ba kamar LTE ba, NR tana goyan bayan faɗuwar mai canzawa, kamar 15/30/60/120/240KHz.Matsakaicin bandwidth mai ɗaukar hoto da ke goyan bayan ya fi LTE, kamar yadda aka nuna a cikin adadi na ƙasa:
| U | Wurin mai ɗaukar hoto | Yawan adadin kowane lokaci | Yawan adadin lokacin kowane firam | Yawan ramin lokaci na kowane ƙaramin yanki |
| 0 | 15 | 14 | 10 | 1 |
| 1 | 30 | 14 | 20 | 2 |
| 2 | 60 | 14 | 40 | 4 |
| 3 | 120 | 14 | 80 | 8 |
| 4 | 240 | 14 | 160 |
|
Ƙididdigar ka'idar ƙimar ƙimar NR tana da alaƙa da bandwidth, yanayin daidaitawa, yanayin MIMO, da takamaiman sigogi.
Mai zuwa shine taswirar albarkatun lokaci-mita
Hoton da ke sama shine taswirar albarkatun lokaci-lokaci wanda ke bayyana a yawancin bayanan LTE.Kuma bari mu ɗan yi magana game da lissafin ƙididdige ƙimar ƙimar ƙimar 5G tare da shi.
2. lissafin NR downlink ganiya kudi
Akwai albarkatu a cikin yankin mita
A cikin 5G NR, ainihin sashin tsara tsarin PRB na tashar bayanai an bayyana shi azaman masu ɗaukar kaya 12 (bambanta da LTE).Bisa ga ka'idar 3GPP, 100MHz bandwidth (30KHz sub-carrier) yana da 273 samuwa PRBs, wanda ke nufin cewa NR yana da 273*12=3276 sub-carriers a cikin mita mita.
Akwai albarkatun a cikin yankin lokaci
Tsawon lokacin ramin daidai yake da LTE, har yanzu 0.5ms, amma a kowane ramin lokaci, akwai alamomin OFDMA 14, la'akari da cewa ana buƙatar amfani da wasu albarkatun don aika sigina ko wasu abubuwa, akwai alamomin kusan 11 waɗanda za a iya amfani da shi wajen watsawa, wannan yana nufin kusan 11 cikin 14 masu dakon mitoci iri ɗaya da ake watsawa tsakanin 0.5ms ana amfani da su wajen isar da bayanai.
A wannan lokacin, 100MHz bandwidth (30KHz subcarrier) a watsa 0.5ms shine 3726*11=36036
Tsarin firam (2.5ms sau biyu a ƙasa)
Lokacin da aka daidaita tsarin firam tare da sake zagayowar 2.5ms biyu, rabon ramin lokaci na musamman shine 10: 2: 2, kuma akwai (5 + 2 * 10/14) raguwa a cikin 5ms, don haka adadin ramukan ƙasa a kowane millise seconds. ya kai 1.2857 Yuro.1s = 1000ms, don haka 1285.7 za a iya tsara ramuka na lokacin saukarwa a cikin 1s.A wannan lokacin, adadin masu jigilar kayayyaki da aka yi amfani da su don tsara tsarin saukar da hanyar sadarwa shine 36036*1285.7
Mai amfani guda ɗaya MIMO 2T4R da 4T8R
Ta hanyar fasahar eriya da yawa, masu amfani da sigina za su iya tallafawa watsa bayanan rafi da yawa a lokaci guda.Matsakaicin adadin saukar hanyar haɗin yanar gizo da rafukan bayanan haɓakawa don mai amfani guda ɗaya ya dogara da ɗan ƙaramin adadin layin liyafar tashar tushe da UE karɓar yadudduka, ƙuntatawa ta ma'anar yarjejeniya.
A cikin 64T64R na tashar tushe, 2T4R UE na iya tallafawa watsa bayanan rafi har zuwa 4 a lokaci guda.
Sigar yarjejeniya ta R15 na yanzu tana goyan bayan matsakaicin yadudduka 8;wato, matsakaicin adadin SU-MIMO yadudduka masu tallafi a gefen hanyar sadarwa shine yadudduka 8.
Babban oda modulation 256 QAM
Mai ɗaukar kaya ɗaya na iya ɗaukar rago 8.
A taƙaice, ƙayyadaddun ƙididdige ƙimar ƙimar ƙa'idar ƙasa:
Mai amfani guda ɗaya: MIMO2T4R
273*12*11*1.2857*1000*4*8=1.482607526.4bit≈1.48Gb/s
Mai amfani guda: MIMO4T8R
273*12*11*1.2857*1000*8*8≈2.97Gb/s
Lokacin aikawa: Afrilu-26-2021