本地異步通信技術(shù)rs-232-資料下載頁
2025-03-02 22:46本頁面
【正文】 頻率處，每一路基帶信號(hào)的頻譜被移到不同的頻段，因此合在一起不會(huì)互相干擾。 ?因此，一條電纜中可以同時(shí)傳送多路的數(shù)字信號(hào)，從而提高了線路的利用率。 Wave Division Multiplexing 波分多路復(fù)用 ? Technically, optical FDM is known as Wave Division Multiplexing(WDM). ? WDM operates by sending multiple light waves across a single optical fiber. ? At the receiving end , an optical prism is used to separate the frequencies. EDAF:光纖放大器，直接對(duì)光信號(hào)進(jìn)行放大。 由于光載波的頻率很高，因此習(xí)慣上用波長表示光載波。 現(xiàn)在可以在一根光纖上復(fù)用 80路或更多路數(shù)的光載波信號(hào)，即密集波分復(fù)用 DWDM（ dense wavelength division multiplexing） Spread Spectrum 擴(kuò)散頻譜 ? A transmitter sends the same signal on a set of carrier frequencies. ? A receiver is configured to check all carrier frequencies and to use whichever is working at present. ? Some modems select a set of carrier frequencies and use them simultaneously. if interference damages one or more of the carriers ,the modem can extract the data from the others. Time Division Multiplexing 時(shí)分多路復(fù)用 ? Time Division Multiplexing(TDM). ? There are two types of TDM: ? Synchronous Time Division Multiplexing(STDM同步時(shí)分多路復(fù)用 ). ? Statistical Multiplexing(統(tǒng)計(jì)多路復(fù)用 ). 作業(yè) 什么是調(diào)制與解調(diào)？調(diào)制與解調(diào)有哪些基本方法？ 載波復(fù)用技術(shù)有哪幾種？各有什么特點(diǎn)？ 習(xí)題： , , 謝謝觀看 /歡迎下載 BY FAITH I MEAN A VISION OF GOOD ONE CHERISHES AND THE ENTHUSIASM THAT PUSHES ONE TO SEEK ITS FULFILLMENT REGARDLESS OF OBSTACLES. BY FAITH I BY FAIT
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