在眾多的網際網路存取方式中,同軸電纜是一個理想的上下行雙向傳輸科技。在多數的發展中國家中有線電視的同軸電纜所提供的寬頻通道能達到很高比例的用戶連結, 這同時是一個理想的高速資料通訊傳輸媒介。
本論文主要目的是研製一個DOCSIS模組,這個系統中包含一個射頻調諧器、上傳用的功率放大器與一個SOC微處理器.當解調器鎖住頭端傳送的QAM載波後,射頻解調器會將指定頻道內的載波內容轉換為中頻訊號送往SOC微處理器,SOC微處理器會將接收到的中頻訊號做解調,完成資料接收.功率放大器是將調變後的訊號送往頭端作解調,在此我們完成同軸電纜上下行雙向的資料通訊。

In many data communications ways, cable is an ideal Internet access technology in the downstream and upstream bidirectional. Cable provides a broadband pipe that can reach a high percentage of the population in many developed countries, and would appear to be an ideal medium for high speed data communications.
The main goal of this thesis is to implement a DOCSIS module that based on an embedded system. In this system, a RF tuner、one PA and one SOC microprocessor are employed. After the lock of the QAM sub-carrier, the RF tuner can transfer the traffic information to microprocessor with IF signal and microprocessor will demodulate the IF signal. The PA transmits modulation sub-carrier to CMTS. Here we will achieve downstream and upstream bidirectional communication.

[1] Data over cable service interface specifications DOCSIS 3.0, CM-TP-MULPIv3.0-ATP-D04-070911 ,CableLabs,Sep 11 2007.
[2] Data over cable service interface specifications DOCSIS 3.0, CM-TP-PHYv3.0-ATP-D02-070223 ,CableLabs,Feb 23 2007.
[3] Data over cable service interface specifications DOCSIS 3.0, CM-SP-MULPIv3.0-I10-090529 ,CableLabs,May 29 2009.
[4] Ferril Losee,“RF Systems, Components, and Circuits Handbook”, Artech House Publishers (September 1997).
[5] Joyce, G.; Bao, J.; Patrick, M.; Flanagan, D ,“DOCSIS IP-Video Bypass Architecture (DIBA), an Architecture for IPTV over Cable ”, Consumer Communications and Networking Conference, 2009. CCNC 2009. 6th IEEE 10-13 Jan. 2009.
[6] James H. Green, "Access Technologies: Dsl and Cable (Executive Briefings in Key Technologies)"Publisher: McGraw-Hill.
[7] David Large, James Farmer , “Broadband Cable Access Networks, Volume 5: The HFC Plant” , Morgan Kaufmann; 3rd Ed edition (October 24, 2008).
[8] Walter Ciciora, James Farmer, David Large,“Modern Cable Television Technology Video, Voice, and Data Communications” , Morgan Kaufmann Publishers; 1st edition (January 15, 1999).
[9] Cable Television Laboratories Inc.,“DOCSIS 3.0 Features” CableLabs June 11 2009
[10] Bing, B.; Lanfranchi, L.,“Optimizing Video Transmission for Broadband Cable Networks” , Consumer Communications and Networking Conference, 2008. CCNC 2008. 5th IEEE 10-12 Jan. 2008 Page(s):1107 - 1111.
[11] Paul H. Young,“Electronic communication techniques”, 5th Edition 尤正祺、曾振東、潘恆堯譯 台灣培生教育出版(Feb 2006).