I-OFDM iye yacetywa kwi-IEEE802.11a. Ngokusekwe kule ndlela yokumodareyitha, kufuneka sazi ukuba yintoni i-OFDM ukuqonda iiprothokholi ezahlukeneyo.
Yintoni iOFDM?
I-OFDM yitekhnoloji ekhethekileyo yokumodareyitha enezinto ezininzi. Le teknoloji ijolise ekwahluleni umjelo kwiitshaneli ezininzi ze-orthogonal sub-channel, kwaye emva koko uguqule izibonakaliso zedatha yesantya esiphezulu kwimithombo yedatha ephantsi yesantya esisezantsi sokuhanjiswa okuhambelanayo, ezihlengahlengiswayo kwaye zidluliselwe kwi-sub-channel nganye. I-subcarrier nganye i-orthogonal ukuya kwelinye, kwaye iziteshi ze-frequency emva kokusasazeka kwe-spectrum modulation zinokudlulana, ukunciphisa ukuphazamiseka phakathi kwee-subcarriers kunye nokuphucula ukusetyenziswa kwe-spectrum.
Indlela yokuqonda i-orthogonal akukho ukuphazamiseka: xa enye i-subcarrier ifikelela kwincopho, i-amplitude yomnye i-subcarrier ngu-0. Oko kukuthi, ii-subcarriers ezimbini zi-orthogonal ngaphandle kokuphazamiseka. Njengoko kubonisiwe kumzobo ongezantsi, xa i-amplitude yokufika eluhlaza okwesibhakabhaka iyeyona iphakamileyo, enye i-subcarrier ngu-0.
Kwakhona, i-OFDM inokusebenzisa ii-subcarriers ezidlulayo kuba ii-subcarriers zichazwa ngendlela eyenza kube lula ukubahlula.
Umqondiso wahlulwe waba subcarriers ezintathu, ukusuka ekhohlo ukuya ekunene. Incopho nganye ye-subcarrier isetyenziselwa ikhowudi yedatha, njengoko kuboniswe kwichaphaza elibomvu kumzobo, ohambelana nomgca wesikali esi-0 ngezantsi. Omnye ufikelela kwincopho, kwaye abanye bafikelela kwi-0. Ezi zixhobo ezincinci zenzelwe ngamabomu ukugcina ubudlelwane be-orthogonal kunye nomnye. Incopho ye-subcarrier nganye Ngeli xesha, i-amplitude yezinye ii-subcarriers ezimbini ngu-0.
5GHz OFDM isitishi:
Ishaneli ye-5GHz ine-52 subcarriers, kwaye i-subcarrier nganye ine-312.5 kHz. Kukho iziteshi ze-48 zokudlulisa idatha, kwaye iziteshi ezi-4 zisetyenziselwa ukubhekisela kwisigaba.
Itekhnoloji ye-OFDM yokumodareyitha ye-subchannel isebenzisa i-QAM (i-QAM sisishunqulelo se-quadrature amplitude modulation, eguqulelwa ngokuthi "quadrature amplitude modulation" ngesiTshayina). I-QAM isebenzisa i-amplitude kunye nesigaba se-carrier wave ukuhambisa ulwazi.
Oku kungentla yingcaciso yolwazi ye-OFDM-802.11 protocol eziswe kuweShenzhen HDV Phoelectron Technology Co., Ltd. ndiyathemba ukuba eli nqaku linokukunceda ukwandisa ulwazi lwakho. Ngaphandle kweli nqaku ukuba ujonge inkampani elungileyo yomenzi wezixhobo zonxibelelwano lwefiber onokuthi uyithathele ingqalelongathi.
Iimveliso zonxibelelwano eziveliswe yikhava yenkampani:
Imodyuli: iimodyuli zefiber optical, Iimodyuli ze-Ethernet, iimodyuli ze-fiber optical transceiver, iimodyuli zokufikelela kwifiber optical, Iimodyuli ze-SSFP ezibonakalayo, kwayeI-SFP optical fibers, njl.
I-ONUudidi: EPON ONU, AC ONU, ifayibha optical ONU, CATV ONU, GPON ONU, XPON ONU, njl.
OLTiklasi: Ukutshintsha OLT, GPON OLT, EPON OLT, unxibelelwanoOLT, njl.
Ezi mveliso zingentla zinokuxhasa iimeko ezahlukeneyo zenethiwekhi. Kwezi mveliso zingentla, iqela elinobuchule nelinamandla le-R & D lidityaniswe ukuze libonelele ngenkxaso yobugcisa kubathengi, kwaye iqela loshishino elicingayo nelinobuchule linokubonelela ngeenkonzo ezikumgangatho ophezulu kubathengi kwangethuba.ukubonisanakwaye emva komsebenzi.