4G Wireless Technology: 4G Wireless Technology Prepared by K.Sai Kumar Yadav 07K81A0584 Outline:
Outline Introduction What is 4G? What's New in 4G?
Features How 4G works Challenges
What is 4G? :
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
at 100 Mbps while moving , and 1 Gbps while stationary .
What's New in 4G? :
What's New in 4G? Entirely packet-switched networks. All network elements are digital. Higher bandwidths to provide
services at lower cost (up to 100Mbps). Tight network security.
Features of 4G Networks: 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 Features of 4G Networks (cont.): 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). 3G vs. 4G: 3G (including 2.5G) 4G Major Requirement Driving Architecture Predominantly voice driven - data was always add on Converged data and voice over IP Network Architecture Wide area cell-based Hybrid - Integration of Wireless LAN (WiFi, Bluetooth) and wide area Speeds 384 Kbps to 2 Mbps 20 to 100 Mbps in mobile mode Frequency Band Dependent on country or continent (1800-2400 MHz) Higher frequency bands (2-8 GHz) Bandwidth 5-20 MHz 100 MHz (or more) Switching Design Basis Circuit and Packet All digital with packetized voice Access Technologies W-CDMA, 1xRTT, Edge OFDM and MC-CDMA (Multi Carrier CDMA) Forward Error Correction Convolution rate 1/2, 1/3 Concatenated coding scheme Component Design Optimized antenna design, multi-band adapters multi-band adapters Smarter Antennas, software multiband and wideband radios IP A number of air link protocols, including IP 5.0 All IP (IP6.0) 3G vs. 4G How 4G works (working principle) : 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: 18.104.22.168 , 22.214.171.124 , 126.96.36.199 , 192.168.5.120 home address care-of address mobile IP address local network address IPv4 vs. IPv6: IPv4 vs. IPv6 IPv4 IPv6 Structure 32 bits 128 bits Security Poor security Enhance security Function Addressing Multi-fun. and mobile fun. are built-in Plug & Play (Auto-Configuration) 4G Systems Challenges: 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 Slide 11: 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 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 First Challenge: Accessing Different Networks 1. Multimode Devices Architecture 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 First Challenge: Accessing Different Networks 2. Overlay Network Architecture Slide 14: 4G Wireless Networks Challenges Second Challenge: Terminal Mobility 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 Second Challenge: Terminal Mobility 1. Location Management: 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 Slide 16: Second Challenge: Terminal Mobility 2. Handoff Management Maintain ongoing communication when the terminal roams IP changes during handoff : 188.8.131.52, home address care-of address mobile IP address local network address 184.108.40.206, IPv6 within the same cell: 220.127.116.11, 192.168.5.120 Slide 17: Second Challenge: Terminal Mobility 2. Handoff Management 18.104.22.168, home address care-of address mobile IP address local network address 22.214.171.124, IPv6 when the terminal roams to another cell: 126.96.36.199, 192.168.5.120 Slide 18: 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 Slide 19: Vertical & Horizontal handoff will increase System load (increasing control packets) Packet losses Handover latency Challenges in Handoff Management Slide 20: Thank you