Amakhasimende amaningi abuza lapho ekhetha aisidluliseli sevidiyo esibucayi- uyini umehluko phakathiIsidlulisi sevidiyo esingenantambo se-COFDMkanye ne-OFDM video transmitter?
I-COFDM Inekhodi ye-OFDM, Kule bhulogi sizoxoxa ngayo ukuze sikusize uthole ukuthi iyiphi inketho engaba ngcono isicelo sakho.
1. OFDM
Ubuchwepheshe be-OFDM buhlukanisa isiteshi esinikeziwe sibe yiziteshi ezincane ze-orthogonal kusizinda samafrikhwensi.Inkampani yenethiwekhi eyodwa isetshenziselwa ukushintshashintsha kwesiteshi ngasinye, futhi inkampani yenethiwekhi ngayinye idluliselwa ngokufana.Ngale ndlela, nakuba isiteshi sisonke singesona isicaba futhi siyakhetha.Kodwa isiteshi esingaphansi ngasinye siyisicaba.Ukudluliselwa kwe-Narrowband kwenziwa esiteshini esincane ngasinye, futhi umkhawulokudonsa wesiginali mncane kunomkhawulokudonsa ohambisanayo wesiteshi.Ngakho-ke, ukuphazamiseka phakathi kwamagagasi esiginali kungaqedwa kakhulu.
Njengoba abathwali besiteshi esincane ngasinye benombono womunye nomunye ohlelweni lwe-OFDM.Ama-spectrum awo adlulela komunye nomunye.Lokhu akunciphisi nje kuphela ukugxambukela phakathi kwama-sub-carriers, kodwa futhi kuthuthukisa ukusetshenziswa kwe-spectrum.
2. COFDM
I-COFDMis I-Coded Orthogonal Frequency Division Multiplexing, okuchaza
ngaphambi kokushintshwa kwe-OFDM, ukusakaza kwekhodi yedijithali kufakwa ikhodi.
Yenzani le Khodi?Ukubhala amakhodi wesiteshi (ukubhala ikhodi komthombo ukuxazulula inkinga yokusebenza kahle, futhi ukubhala ikhodi kwesiteshi ukuqinisekisa ukwethembeka kokudluliswa kwedatha).
Indlela eqondile yilena:
2.1.Ukulungiswa Kwephutha Langaphambili(FEC)
Isibonelo, amabhithi edatha ayi-100 adinga ukushintshwaokwehambisaing.Okokuqala shintsha ibe amabhithi angu-200,.Uma isignali yamukelwe, noma ngabe kunenkinga ngokudluliswa kwamabhithi ayi-100, idatha elungile isengakhishwa.Ngamafuphi, kuwukwengeza ukuphindaphindeka ngaphambi kokushintshashintsha ukuze kuthuthukiswe ukwethembeka kokudlulisela.Lokhu kubizwa ngokuthi Ukulungiswa Kwephutha Langaphakathi (FEC) ezinhlelweni ze-COFDM.Namit iyipharamitha ebalulekile yohlelo lwe-COFDM.
2.2.Isikhawu Sonogada
Fnoma inhloso ye-solvingi-multi-inkinga yendlelaleyoisignali edlulisiwe ifinyelela ekugcineni kokwamukela ngokusebenzisa izindlela eziningi zokudlulisela. Aisikhawu sokuqapha sifakwa phakathi kwamabhithi edatha adlulisiwe.
3.Isiphetho
Umehluko phakathi kwe-COFDM ne-OFDM ukuthi amakhodi okulungisa amaphutha nezikhawu zonogada zengezwa ngaphambi kokushintshwa kwe-orthogonal ukwenza ukudluliswa kwesignali kusebenze kakhulu.
I-OFDM ixazulula ukuphela kokukhetha kwesiteshi kuningi-imvelo yendlela kahle, kodwa ayikakunqobi ukufiphala kwesiteshi.
I-COFDM ivumela ukufiphala kwesiginali yekhodi yeyunithi ngayinye ngesikhathi sokudlulisela kubhekwe njengokuzimele ngokwezibalo ngokubhala amakhodi, ngaleyo ndlela kuqedwe umthelela wokufiphala okuyisicaba kanye nokushintshwa kwefrikhwensi ye-Doppler.
4.Ukusetshenziswa kwe-OFDM ne-COFDM
I-COFDM ifaneleka kakhulu ukudluliswa okungenantambo ngesikhathiijubane eliphezuluezihambayo.Njenge Hd wngenasiciti-ransmittervehiclemi-unt, imikhumbiukuxhumana kwe-mesh, izindiza ezinophephela emhlaneCofdm Hd Transmitter kanyelonrintukuthelodironivumbonoti-ransmitter.
I-COFDM futhi inekhono eliqinile le-nlos.Ilungele ukusetshenziswa ezindaweni ezingabonwayo nezithiyekile njengezindawo zasemadolobheni, izindawo ezingaphansi kwedolobha, nezakhiwo, futhi ikhombisa amakhono amahle kakhulu "okuphazamiseka" kanye "nokungena".
I-OFDM ivumela ukusetshenziswa okuphakeme okuphumelelayo kwe-spectrum futhi ingamelana nokufiphala kokukhetha imvamisa, ehlala isetshenziswa kunethiwekhi ye-LTE ne-wifi.
Isikhathi sokuthumela: Jun-12-2023
