EE 551451, Fall, 2006 Communication Systems

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EE 551/451, Fall, 2006Communication Systems

• Zhu Han
• Department of Electrical and Computer Engineering
• Class 29
• Dec. 7th, 2006

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Statistics

• Grade based on relative values and clusters. Do
  not be the outlier.

Midterm mean 52.4
Project 1 mean 6.44
homework mean 8.16
Project 2 mean 8.39
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Final Exam

• Exam Tuesday, December 12th at 330 - 530 p.m.
  in ET314.
• 50 why questions and 5 big questions (10 point
  each)
• Nyguist sampling theory
• Line coding
• Pulse Shaping
• Digital modulation
• Coding theory
• For big questions Home works and examples
• For concept questions slides, if questions, come
  to my office or call me.
• Office hour, Friday, Monday from 930am to 500pm
  
• Email, phone [phone], during weekend for
  part-time

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Outline

• PSTN basic phone services
• Connect to the backbone
• ISDN
• Cable Modem
• ADSL
• Hybrid Fiber Coax
• Backbone
• DS0, DS1, DS3, OC1, OC3, OC12, OC48, OC192
• ATM
• Wireless cellular phone, WLAN, WMAN,
• Video video standard, video on demand, HDTV
• Satellite communication and GPS
• Transmission media twisted wires, coax, cable,
  radio

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Public switched telephone network (PSTN)

• Major Components of the Public Switched Telephone
  Network (PSTN)
• Switching Offices, Transmission facilities,
  Customer Premise Equipment

Switching Office
Switching Office
CPE
CPE
Transmission Facilities
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Integrated Services Digital Network (ISDN)

• Telephone services -gt Telecommunication services
• Used for voice, image and data
• Types of channels
• Bearer channel (B-channel64 kb/s) clear pipe for
  data
• Delta channel (D-channel, 16 kb/s or 64 kb/s)
  call signaling information
• who is calling
• type of call
• calling what number
• Service types
• Basic Rate Interface (2 B channels 1 D channel)
• Primary Rate Interface (30 B channels 1 D
  channel)

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56 k Technology (modem connection)
Analog line
Access server
Digital line
Telephone switch
Telephone switch
?
Modem
lt 33,6 kbps
Modem
Access server
Modem
lt 56 kbps
ISDN, E1,..
lt 33,6 kbps
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Asymmetrical Digital Subscriber Line ADSL

• ADSL is the 1 Broadband Choice in the World with
  over 60 market share
• ADSL is now available in every region of the
  world
• ADSL is capable of providing up to 50 Mbp, and
  supports voice, video and data.
• The new DSL network is IP-centric
• There is broad equipment interoperability and
  there are currently established test
  specifications for ADSL, ADSL2plus, SHDSL, and
  VDSL
• Finally, ADSL and home networking are a natural
  fit as DSL effectively supports multiple
  applications for multiple uses via each DSL
  connection.

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ADSL Networks
Video Servers
ADSL
Internet
Broadband Network
1.5 to 8Mbit/s
9.6 to 640kbit/s
Telephone Network
Live Broadcast
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ADSL Modem Structure
Mbit/s
Mbit/s
ADSL Modem
ADSL Modem
kbit/s
kbit/s
Line
POTS Filter
POTS Filter
POTS Linecard
Exchange End
Customer End
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Cable Modem

• A digital service offered by cable television
  companies
• Data Over Cable Service Interface Specifications
  (DOCSIS)
• Most common protocol used for cable modems
• Not a formal standard
• Offers vary (depends on the quality of cable
  plant)
• In theory downstream 27-55Mbps upstream 2-10
  Mpbs
• Typical downstream 1.5 -2 Mbps upstream 0.2
  2 Mbps
• A few cable companies offer downstream services
  only
• Upstream communications using regular telephone
  lines
• Cable modems use shared multipoint circuits
• All messages on the circuit heard by all
  computers on the circuit ? security issue
• 300 1000 customers per cable segment

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Basic Cable Modem Architecture
Cable Company Distribution Hub
Cable Company Fiber Node
Customer Premises
Cable Splitter
Cable Modem
TV Video Network
Combiner
Downstream
Upstream
Optical/ Electrical Converter
Hub
TV
Router
Shared Coax Cable System
Cable Company Fiber Node
Cable Modem Termination System
Computer
Computer
ISP POP
Customer Premises
Customer Premises
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Hybrid Fiber Coax
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Fiber in the CATV Network

• Fiber Optic will increase quality, reliability,
  and operational savings.
• Fiber Optic is economically competitive in
  comparison with coaxial cable.
• Fiber Optic offers the opportunity of two-way
  services, fact that will increment revenues for
  the company.
• Fiber Optic networks are fully expandable, with
  large capacities to provide countless services.

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T Carrier System
Twisted Wire to Cable System
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Fiber Communication
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Asynchronous Transfer Mode (ATM)

• Designed by phone companies
• Single technology meant to handle
• Voice
• Video
• Data
• Intended as LAN or WAN
• End-to-end (application to application)
• Connection-oriented interface
• Establish connection
• Send data
• Close connection
• Performance guarantees (statistical)
• Uses cell switching

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ATM Cell, Virtual Circuit

• ATM cell 53 byte
• 48 bytes of data and
• 5 bytes of header
• information

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Successes and failures of ATM

• Goal replacement for Internet
• ATM has proved very successful in the WAN
  scenario
• We know that there will always be both brand-new
  and obsolescent link-layer technologies,
  particularly in the LAN area, and it is fair to
  assume that not all of them will fit neatly into
  the synchronous optical networking model that ATM
  was designed for. Therefore, some sort of
  protocol is needed to provide a unifying layer
  over both ATM and non-ATM link layers, and ATM
  itself cannot fill that role. Conveniently, we
  have this protocol called "IP" which already does
  that. Ergo, there is no point in implementing ATM
  at the network layer.
• Gigabit Ethernet implementations
  (10Gbit-Ethernet, Metro Ethernet) will replace
  ATM as a technology of choice in new WAN
  implementions.

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Transmission Media
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Wireless Communications

• Next Semester
• Cellular Phone
• WLAN WIFI
• 
  WMAN WIMAX

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Radio System Propagation
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Satellite Communications

• Large communication area. Any two places within
  the coverage of radio transmission by satellite
  can communicate with each other.  
• Seldom effected by land disaster ( high
  reliability)
• Circuit can be started upon establishing earth
  station (prompt circuit starting)
• Can be received at many places simultaneously,
  and realize broadcast, multi-access communication
  economically( feature of multi-access)
• Very flexible circuit installment , can disperse
  over-centralized traffic at any time.
• One channel can be used in different directions
  or areas (multi-access connecting).

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GPS

• Just a timer, 24 satellite
• Calculation position

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Video Standard

• Two camps
• H261, H263, H264
• MPEG1 (VCD), MPEG2 (DVD), MPEG4
• Spacial Redundancy JPEG
• Intraframe compression
• DCT compression Huffman coding
• Temporal Redundancy
• Interframe compression
• Motion estimation

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Discrete Cosine Transform (DCT)
0 black 255 white
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DCT and Huffman Coding
0 black 255 white
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Motion Compensation

• I-Frame
• Independently reconstructed
• P-Frame
• Forward predicted from the last I-Frame or
  P-Frame
• B-Frame
• forward predicted and backward predicted from the
  last/next I-frame or P-frame

Transmitted as - I P B B B P B B B
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Motion Prediction
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HDTV
4-7 Mbps
25 - 27 Mbps
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Final Remarks

• Student, teacher, competitor Tent, ring, and
  wind
• Motivation for study kayak upstream
• Interdisciplinary study
• Middle class for sure
• Viterbi retired
• Dr. Jake Baker well-known
• Rowan Atkinson former BBC engineer
• Hope you have studied something and
• Wish you success.
• If so, do not forget BSU

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Questions?