Chapter 9 Communications Circuits 9.4.6 T-carrier system T-carrier systems are a family of high speed digital transmission systems. A T-1 circuit can carry data at 1.544 Mbps 9. 4.7 Fractional t-1 p175 www.gxmu.edu.cn
9.4.6 T-carrier system T-carrier systems are a family of highspeed digital transmission systems. A T-1 circuit can carry data at 1.544 Mbps. 9.4.7 Fractional T-1 P175 www.gxmu.edu.cn Chapter 9 Communications Circuits
Chapter 9 Communications Circuits 9.4.8 Digital Subscriber Line SL A communication line technology that provides high-speed, asymmetric, dedicated point-to-point, public network access over twisted pair copper wire between a network service provider's central office and the customer' s site is called adsl www.gxmu.edu.cn
9.4.8 Digital Subscriber Line (DSL) A communication line technology that provides high-speed, asymmetric, dedicated point-to-point, public network access over twisted pair copper wire between a network service provider's central office and the customer's site is called ADSL. www.gxmu.edu.cn Chapter 9 Communications Circuits
Chapter 9 Communications Circuits Power or Amplitude Voiceband Upstream Downstream Band Band Frequency 4 kHz 2.2 MHZ Figure 9-5 An ADSL circuit is divided into several channels, and uses a much wider frequency range than a standard telephone circuit. www.gxmu.edu.cn
Figure 9-5 An ADSL circuit is divided into several channels, and uses a much wider frequency range than a standard telephone circuit. www.gxmu.edu.cn Chapter 9 Communications Circuits
Chapter 9 Communications Circuits 94.8 Digital Subscriber Line SL) A dSL technology that provides equal speed channels in both directions and may not include a telephone channel is called SDSL VDsL transmits data at top speeds of 51 to 55 Mbps and is asymmetric www.gxmu.edu.cn
9.4.8 Digital Subscriber Line (DSL) A DSL technology that provides equal speed channels in both directions and may not include a telephone channel is called SDSL. VDSL transmits data at top speeds of 51 to 55 Mbps and is asymmetric. www.gxmu.edu.cn Chapter 9 Communications Circuits
Chapter 9 Communications Circuits 9.4.9 Cable TV(CATV Circuits CATV systems often have to be reengineered before they can carry signals in both directions. Using a catV circuit for data transmission requires a modem to be installed on the cable at the user's home or office 9. 4.10 Satellite circuits DSS can be used to provide high-speed access to the internet www.gxmu.edu.cn
9.4.9 Cable TV (CATV) Circuits CATV systems often have to be reengineered before they can carry signals in both directions. Using a CATV circuit for data transmission requires a modem to be installed on the cable at the user’s home or office. 9.4.10 Satellite Circuits DSS can be used to provide high-speed access to the Internet. www.gxmu.edu.cn Chapter 9 Communications Circuits