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pankaj tripathi

pankaj tripathi

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  • 1. 4G Wireless Networks ST.FRANCIS DE SALES COLLEGE Electron IC City Hebbgodi Bangalore NEHA PRESENTATION Prepared by NEHA PANDEY
  • 2. Outline
    • Introduction
      • What is 4G?
      • What's New in 4G?
    • 3G vs. 4G
    • 4G Network Features
    • How 4G works
    • Challenges
    • Summary
  • 3. What is 4G?
    • A wireless access technology and is the successor of 3G.
    • Called "3G and Beyond".
    • Enables seamless roaming between technologies.
    • Plans on releasing the first commercial network in 2010 .
    • NTT DoCoMo Company is testing 4G communication at 100 Mbps while moving , and 1 Gbps while stationary .
  • 4. What's New in 4G?
    • Entirely packet-switched networks.
    • All network elements are digital.
    • Higher bandwidths to provide multimedia services at lower cost (up to 100Mbps).
    • Tight network security.
  • 5. Features of 4G Networks
    • 4G networks are all-IP (Internet Protocol) based heterogeneous networks
    • This will allow users to:
      • Select any system at any time and any where
      • Use Multiple systems at the same time (e.g. GPS and WLANs and CDMA)
    • A wide range of applications using only one 4G integrated terminal
  • 6. Features of 4G Networks (cont.)
    • Support interactive multimedia services: teleconferencing, wireless Internet, etc.
    • Wider bandwidths, higher bit rates.
    • Global mobility and service portability.
    • Low cost.
    • Scalability of mobile networks (>10 times the capacity of 3G).
  • 7. 3G vs. 4G From : www.mobileinfo.com All IP (IP6.0) A number of air link protocols, including IP 5.0  IP  multi-band adapters Smarter Antennas, software multiband and wideband radios Optimized antenna design, multi-band adapters  Component Design Concatenated coding scheme Convolution rate 1/2, 1/3 Forward Error Correction OFDM and MC-CDMA (Multi Carrier CDMA) W-CDMA, 1xRTT, Edge Access Technologies All digital with packetized voice Circuit and Packet Switching Design Basis 100 MHz (or more) 5-20 MHz Bandwidth Higher frequency bands (2-8 GHz) Dependent on country or continent (1800-2400 MHz) Frequency Band 20 to 100 Mbps in mobile mode 384 Kbps to 2 Mbps Speeds Hybrid - Integration of Wireless LAN (WiFi, Bluetooth) and wide area Wide area cell-based Network Architecture Converged data and voice over IP Predominantly voice driven - data was always add on Major Requirement Driving Architecture  4G 3G (including 2.5G)
  • 8. How 4G works (working principle)
    • The IP address is based on IPv6.
    • IPv4: X . X . X . X (32 bits)
    • example: 216 . 37 . 129 . 9
    • IPv6: 4 × IPv4 (128 bits)
    • example:
    • 216.37.129.9 , 79.23.178.229 , 65.198.2.10 , 192.168.5.120
    home address care-of address mobile IP address local network address
  • 9. IPv4 vs. IPv6
    • Multi-fun. and mobile fun. are built-in
    • Plug & Play (Auto-Configuration)
    Addressing Function Enhance security Poor security Security 128 bits 32 bits Structure IPv6 IPv4
  • 10. The 4G mobile network(s) HAPS GSM UMTS WLAN Bluetooth Satellite Wireline or Wireless Networks (Internet) ADSL Home Add. Mobile IP Add. Care-of Add. Care-of Add. Services Content Very wide area Wide area Metropolitan area Local area Personal area Direct Sequence Frequency Hopping WCDMA TD-CDMA TDMA FDD OFDM TDD OFDM Unspecified
  • 11. 4G Systems Challenges
    • To migrate current systems to 4G with the features mentioned previously, researchers are facing a number of challenges
    • These challenges are grouped into the following different aspects:
      • Accessing Different Networks:
        • Multimode Devices
        • Overlay Network
      • Terminal Mobility
        • Location Management
        • Handoff Management
  • 12.
    • One of the most challenging problems facing deployment of 4G technology is how to access several and different mobile and wireless networks
    • There are two possible architectures
      • Multimode Devices
      • Overlay Network
    4G Wireless Networks Challenges First Challenge: Accessing Different Networks
  • 13. First Challenge: Accessing Different Networks 1. Multimode Devices Architecture
    • A single physical terminal with multiple interfaces to access the different wireless networks
    • Advantages:
      • Improve call completion
      • Expand coverage area
      • Reliable coverage in case of network, link or switch failure
    • Disadvantages:
      • Complexity in the hardware of the device
    • Handoff Mechanism:
    • Performed by the user, device or network
  • 14. To reduce the complexity of the hardware in the device the most promising technology is to adapt the software radio approach BPF LNA ADC reprogrammable Baseband DSP User Analogue Digital An ideal software radio system Multimode Devices Architecture (cont.) Analog/digital converter bandpass filter Low noise amplifier
  • 15.
    • High number of antennas : Still It is impossible to have just one antenna and one LNA to cover the bands of all 4G wireless networks
    • The low speed of ADCs . the speed of the fastest current ADC is still two to three times slower than required
    Multimode Devices Architecture (cont.) Challenges in software radio technology
  • 16. First Challenge: Accessing Different Networks 2. Overlay Network Architecture
    • A user accesses an overlay network consisting of several UAPs
    • UAPs Functions:
      • Select a wireless network based on availability and user choices
      • Store IPs of user, network and devices
    • Advantages:
      • Simplify hardware of device
      • Supports single billing
    • Disadvantages:
      • More network devices
    • Handoff Mechanism between UAPs:
    • Performed by overlay network rather than the user or device
  • 17.
    • In order to provide wireless services at any time and anywhere, terminal mobility is a must in 4G infrastructure
    • Terminal mobility allows mobile clients to roam across geographical boundaries of the wireless networks
    • There are two main issues in terminal mobility:
      • location management
      • handoff management
    4G Wireless Networks Challenges Second Challenge: Terminal Mobility
  • 18.
    • The system tracks and locates a mobile terminal for possible connection
    • Location management involves handing all the information about
      • Roaming terminals such as original and current location cells
      • Authentication information
      • QoS capabilities
    Second Challenge: Terminal Mobility 1. Location Management
  • 19. Second Challenge: Terminal Mobility 2. Handoff Management
    • Maintain ongoing communication when the terminal roams
    • IP changes during handoff :
    216.37.129.9, home address care-of address mobile IP address local network address 79.23.178.229, IPv6 within the same cell: 65.198.2.10, 192.168.5.120
  • 20. Second Challenge: Terminal Mobility 2. Handoff Management 216.37.129.9, home address care-of address mobile IP address local network address 79.23.178.229, IPv6 when the terminal roams to another cell: 65.198.2.10, 192.168.5.120
  • 21.
    • Horizontal handoff is performed when the terminal moves from one cell to another within the same wireless system.
    • Vertical handoff is performed when the terminal moves between two different wireless systems (e.g., from WLAN to GSM) .
    Handoff Management (cont.) Handoff Management Challenges
  • 22.
    • Vertical & Horizontal handoff will increase
      • System load (increasing control packets)
      • Packet losses
      • Handover latency
    • Hard correct handoff time : because measuring handoffs is done among different wireless systems
    Challenges in Handoff Management
  • 23. Summary
    • The key concept behind 4G systems is integrating their capacities with all of the existing mobile technologies through advanced technologies
    • The IP address system used in 4G is based on the new technology IPv6.
    • 4G networks is still in the development stage, and in order to utilize their new features too many challenges must be overcome