Thaum peb xa cov teeb liab, txawm tias nws yog lub teeb liab kho qhov muag, lub teeb liab hluav taws xob, lossis lub teeb liab wireless, yog tias nws raug xa ncaj qha, lub teeb liab tau yooj yim cuam tshuam los ntawm lub suab nrov, thiab nws nyuaj rau kom tau txais cov ntaub ntawv raug thaum kawg tau txais. Txhawm rau txhim kho qhov muaj peev xwm tiv thaiv kev cuam tshuam ntawm qhov system, nws tuaj yeem ua tiav los ntawm kev hloov kho lub teeb liab. Modulation tseem tuaj yeem ua kom zoo dua ntawm kev siv cov channel, yog li nws muaj txiaj ntsig zoo rau kev sib txuas lus zoo thiab kev ntseeg siab ua haujlwm li cas.
Lub kaum sab xis modulation tau piav qhia hauv qab no yog rau cov cim analogue.
Lub sinusoidal carrier muaj peb yam tsis muaj:amplitude, zaus, thiab theem. Peb tuaj yeem thauj cov ntaub ntawv ntawm cov teeb liab modulated tsis tsuas yog nyob rau hauv lub amplitude hloov ntawm tus cab kuj tab sis kuj nyob rau hauv zaus los yog theem hloov ntawm tus cab kuj. Thaum lub sijhawm hloov kho, yog tias qhov zaus ntawm cov cab kuj sib txawv nrog cov teeb liab hloov kho, nws yog hu ua zaus hloov kho lossis zaus hloov pauv (FM); Yog hais tias theem ntawm tus cab kuj txawv nrog cov teeb liab modulation, nws yog hu ua theem modulation los yog theem modulation (PM) Nyob rau hauv ob hom kev hloov kho, qhov amplitude ntawm tus cab kuj tseem nyob tas li, thiab qhov kev hloov ntawm zaus thiab theem yog qhia raws li qhov hloov ntawm instantaneous theem ntawm cov cab kuj. Yog li ntawd, FM thiab theem kev hloov pauv tau raug hu ua lub kaum sab xis.
Qhov txawvnruab nrab ntawm lub kaum sab xis thiab amplitude modulation yog hais tias lub modulated teeb liab spectrum tsis yog linear hloov ntawm tus thawj modulated teeb liab spectrum, tab sis lub nonlinear transformation ntawm lub spectrum, uas yuav tsim tshiab zaus Cheebtsam txawv ntawm lub spectrum hloov, yog li nws kuj hu ua. tsis linear modulation.
FM thiab PMyog dav siv nyob rau hauv kev sib txuas lus systems. FM tau dav siv hauv kev tshaj tawm suab paj nruag siab, TV suab teeb liab kis tau tus mob, kev sib txuas lus satellite, thiab xov tooj ntawm tes. Ntxiv nrog rau kev siv ncaj qha rau kev sib kis, PM kuj tseem siv tau los ua kev hloov pauv rau indirectly generating FM signals. Muaj kev sib raug zoo ntawm kev hloov pauv zaus thiab theem kev hloov pauv.
Piv nrog rau amplitude modulation technology, qhov zoo tshaj plaws ntawm lub kaum sab xis modulation yog nws cov kev ua haujlwm siab tiv thaiv suab nrov. Txawm li cas los xij, muaj qhov nce thiab poob. Tus nqi ntawm qhov tau txais qhov txiaj ntsig no yog tias lub kaum sab xis hloov kho nyob ntawm qhov dav bandwidth dua li lub teeb liab amplitude modulation.
Cov saum toj no yog cov lus piav qhia ntawm cov ntsiab lus kev paub txog nonlinear modulation (lub kaum sab xis modulation) coj HDV photoelectric Technology Co., Ltd. Shenzhen HDV photoelectric Technology Co., Ltd. yog cov chaw tsim khoom ntawm cov khoom sib txuas lus. Tam sim no, cov cuab yeej tsim tawm npog covONU series, Optical module series, OLT series, thiabtransceiver series. Peb tuaj yeem muab cov kev pabcuam customized rau cov xwm txheej sib txawv. Zoo siab txais tossab laj.
