Lus Nug: Qhov blog no feem ntau qhia txog cov yam ntxwv ntawm daim ntawv thov thiab qhov zoo ntawm COFDM thev naus laus zis hauv kev xa xov wireless, thiab thaj chaw thov ntawm cov thev naus laus zis.
Ntsiab lus: tsis-line-ntawm-pom;Tiv thaiv kev cuam tshuam;Tsiv ntawm kev kub ceev; COFDM
1. Dab tsi yog cov kev sib txuas lus wireless?
Cov txheej txheem kev siv hauv kev sib txuas lus wireless tuaj yeem muab faib ua piv txwv, sib kis cov ntaub ntawv / xov tooj cua hauv Internet, GSM / GPRS CDMA, digital microwave (feem ntau kis tau tus mob microwave), WLAN (wireless network), COFDM (orthogonal zaus division multiplexing), thiab lwm yam. . Ntawm lawv, cov thev naus laus zis niaj hnub tsis tuaj yeem ua tiav broadband high-speed kis tau tus mob nyob rau hauv "kev thaiv, tsis pom kev thiab kev kub ceev mobile tej yam kev mob", nrog rau kev txhim kho thiab kev loj hlob ntawm OFDM thev naus laus zis, qhov teeb meem no muaj kev daws teeb meem.
2. COFDM technology yog dab tsi?
COFDM (coded orthogonal zaus division multiplexing), uas yog, coding orthogonal zaus division multiplexing, ntxiv rau lub zog coding yuam kev kho muaj nuj nqi, qhov loj tshaj feature yog multi-carrier modulation, uas faib ib tug muab channel rau hauv ntau orthogonal sub-channels zaus domain, siv ib tug subcarrier rau txhua sub-channel, thiab decomposes cov ntaub ntawv ntws mus rau hauv ob peb sub-data kwj, decomposing cov ntaub ntawv txaus tus nqi, cov sub-cov ntaub ntawv kwj no ces siv los hloov kho txhua subcarrier nyias.
Kev sib kis ntawm txhua tus subcarrier txo qhov kev cia siab ntawm ib tus neeg nqa khoom, thiab nws cov peev xwm tiv thaiv ntau yam kev cuam tshuam, kev cuam tshuam los ntawm kev cuam tshuam (ISI) muaj peev xwm, thiab Doppler zaus hloov pauv tau zoo dua.
Kev siv COFDM thev naus laus zis tuaj yeem paub txog kev sib kis ceev ceev hauv kev cuam tshuam, tsis pom kev thiab kev kub ceev mobile, uas tam sim no yog qhov kev hloov kho tshiab tshaj plaws thiab pheej hmoo tshaj plaws hauv ntiaj teb.
3. Dab tsi yog qhov zoo ntawm COFDM thev naus laus zis hauv kev xa xov wireless?
Kev xa xov wireless mus dhau ob theem: analog thiab digital kis.Kev xa cov duab analog tau raug tshem tawm hauv ntau qhov kev lag luam vim nws cuam tshuam thiab kev cuam tshuam ntawm kev sib koom ua ke thiab suab nrov superposition, uas ua rau muaj kev cuam tshuam tsis zoo hauv kev siv tswv yim.
Nrog rau kev loj hlob ntawm OFDM thev naus laus zis thiab cov khoom siv, cov khoom siv COFDM thev naus laus zis tau dhau los ua cov khoom siv wireless kis tau zoo tshaj plaws.Nws qhov zoo yog raws li nram no:
1, Nws yog tsim rau daim ntawv thov nyob rau hauv Tsis muaj-kab-ntawm-pom thiab obstructed ib puag ncig xws li nroog, suburbs, thiab vaj tse, thiab qhia tau hais tias zoo heev "diffraction thiab nkag mus" muaj peev xwm.
COFDM wireless duab cov cuab yeej muaj qhov zoo ntawm "tsis-kab-ntawm-pom" thiab "diffraction" kis tau tus mob vim nws cov cab kuj thiab lwm yam kev ua haujlwm, Hauv nroog, roob, sab hauv thiab sab nrauv vaj tse thiab lwm qhov chaw uas tsis tuaj yeem pom. thiab obstructed, lub cuab yeej tuaj yeem ua tiav kev sib kis tau zoo ntawm cov duab nrog qhov ua tau zoo, thiab tsis cuam tshuam los ntawm ib puag ncig lossis tsis cuam tshuam los ntawm ib puag ncig.
Omnidirectional kav hlau txais xov feem ntau yog siv nyob rau hauv ob qho tib si kawg ntawm lub transceiver thiab receiver, thiab lub system deployment yog yooj yim, txhim khu kev qha, thiab saj zawg zog.
2, Nws yog tsim rau high-speed mobile kis tau tus mob, thiab tuaj yeem siv rau tsheb, nkoj, nyoob hoom qav taub / drones thiab lwm lub platform.
Ib txwm siv microwave, wireless LAN thiab lwm yam khoom siv tsis tuaj yeem paub txog kev sib kis ntawm lub xov tooj ntawm tes ntawm lub transceiver kawg thiab tsuas tuaj yeem paub txog kev xa xov ntawm lub xov tooj ntawm tes mus rau qhov chaw ruaj khov hauv qee qhov xwm txheej.Nws cov kab ke muaj ntau yam kev sib txuas, kev tsim vaj tsev, kev ntseeg tau txo qis, thiab tus nqi siab heev.
Txawm li cas los xij, rau cov cuab yeej COFDM, nws tsis tas yuav muaj cov khoom siv ntxiv, nws tuaj yeem paub txog kev siv cov khoom siv ruaj khov, cov chav txawb txawb, thiab yog qhov tsim nyog rau kev teeb tsa ntawm lub platform xws li tsheb, nkoj, nyoob hoom qav taub / drones, thiab lwm yam. Cov kis tau tus mob muaj kev ntseeg siab thiab kev ua haujlwm siab.
3, Nws yog tsim rau high-ceev cov ntaub ntawv kis tau tus mob, feem ntau ntau dua 4Mbps, kom tau raws li cov kis tau tus mob ntawm high-zoo video thiab suab.
Ntxiv rau qhov yuav tsum tau muaj rau cov koob yees duab, cov yeeb yaj kiab zoo thiab lub suab muaj cov kev xav tau siab heev rau kev nkag siab cov kwj thiab cov channel tus nqi, thiab txhua tus subcarrier ntawm COFDM thev naus laus zis tuaj yeem xaiv QPSK, 16QAM, 64QAM thiab lwm yam kev hloov pauv siab, thiab cov khoom siv hluav taws xob sib txuas. feem ntau yog ntau dua 4Mbps.Yog li ntawd, nws tuaj yeem xa 4: 2: 0, 4: 2: 2 thiab lwm yam zoo codecs hauv MPEG2, thiab cov duab daws teeb meem ntawm qhov kawg tau txais tuaj yeem ncav cuag 1080P, uas ua tau raws li qhov xav tau ntawm kev tshuaj xyuas tom qab, khaws cia, kho thiab kho. yog li ntawd.
4, Nyob rau hauv complex electromagnetic ib puag ncig, COFDM muaj kev tiv thaiv zoo heev los cuam tshuam.
Nyob rau hauv ib lub tshuab nqa ib leeg, ib qho fading lossis cuam tshuam tuaj yeem ua rau tag nrho cov kev sib txuas lus tsis ua haujlwm, tab sis nyob rau hauv ib qho kev sib txuas lus COFDM, tsuas yog ib feem me me ntawm subcarriers raug cuam tshuam nrog, thiab cov subchannels kuj tuaj yeem raug kho nrog cov lej yuam kev. los xyuas kom meej qhov tsawg me ntsis yuam kev ntawm kev sib kis.
5 、 Kev siv channel yog siab.
Qhov no yog qhov tseem ceeb tshwj xeeb tshaj yog nyob rau hauv ib puag ncig wireless nrog cov peev txheej spectrum tsawg, qhov twg kev siv spectrum ntawm lub kaw lus zoo li 2Baud / Hz thaum muaj pes tsawg tus subcarriers loj.
Siv COFDM thev naus laus zis rau IWAVE's wireless video transmitter
Tam sim no COFDM tau dav siv hauv DVB (Digital Video Broadcasting), DVB-T, DVB-S, DVB-C thiab lwm yam rau kev kub ceev UAV cov ntaub ntawv kis tau tus mob.
Nrog rau kev txhim kho thev naus laus zis, muaj ntau thiab ntau dua drones thiab UAV ua haujlwm rau tib neeg hauv qhov project sib txawv.IWAVE tsom rau kev tsim, tsim, thiab muag cov kev sib txuas lus wireless rau kev lag luam drones thiab robotics.
Cov kev daws teeb meem yog 800Mhz, 1.4Ghz, 2.3Ghz, 2.4Ghz thiab 2.5Ghz, 5km-8km, 10-16km thiab 20-50km video thiab digital Bi-directional Serial Data Links nrog COFDM thev naus laus zis.
Qhov kev ya saum toj kawg nkaus peb qhov kev txhawb nqa yog 400km / h.Thaum lub sij hawm xws li kev kub ceev lub kaw lus kuj tseem tuaj yeem ua kom cov teeb liab video ruaj khov.
Rau luv luv 5-8km, OFDM yog siv rau UAV / FPV los yog Multi rotor video kis tau tus mob rau video, Ethernet teeb liab thiab serial cov ntaub ntawv xws liPIB-2405thiabFIM-2405.
Rau qhov ntev 20-50km, peb pom zoo cov khoom lag luam zoo li noFIM 2450thiabPEB 2420
IWAVE's txais cov thev naus laus zis COFDM rau peb cov khoom, tsom mus rau kev tsim cov kev sib txuas lus ceev ceev ceev.Raws li 14years ntawm kev siv tshuab thiab kev paub dhau los, peb ua qhov chaw hauv cheeb tsam los ntawm kev ntseeg tau ntawm cov khoom siv nrog lub peev xwm NLOS muaj zog, kev ua haujlwm ntev ntev thiab kev ua haujlwm ruaj khov hauv UAV, neeg hlau, tsheb sib txuas lus wireless.
Yam khoom pom zoo
Post lub sij hawm: Apr-20-2023
