Wireless Wide Area Network Notes

Wireless Wide Area Network Overview

  • 1G Wireless System (1980s):

    • Developed with the Advanced Mobile Phone Service (AMPS) using Frequency Division Multiplexing Access (FDMA).
    • Carried analog voice over the 800 MHz frequency band.

  • 2G Wireless System (1990s):

    • Emergence of digital voice standards with two main technologies:
    • IS-95 (CDMA): Multiplexed up to 64 calls per channel (800 MHz).
    • GSM (GPRS): Used Time Division Multiple Access (TDMA), multiplexing 8 calls per channel (900/1800 MHz).

3G Wireless System

  • Definition: International Telecommunications Union (ITU) defined it as IMT-2000 to ensure growth, increase bandwidth, and support multimedia applications.
  • Features:
    • GSM could support circuit-switched data at 14.4 Kbps.
    • Transitioning from 2G required both evolutionary upgrades of existing networks and revolutionary planning for new systems.
  • 3G Families:
    • 3GPP (1998): Evolved GSM technologies.
    • GPRS: Up to 114 Kbps.
    • EDGE: Up to 384 Kbps.
    • UMTS (WCDMA): Downlink speeds of 1.92 Mbps.
    • HSDPA: Up to 14 Mbps (166 networks in 75 countries by 2007).
    • 3GPP2: For North American/Asian CDMA2000 operators.
    • 1xRTT: Up to 144 Kbps.
    • EV-DO: Increased speeds to 2.4 Mbps and later enhancements to 4.9 Mbps.
  • Next Steps: Move towards LTE E-UTRA (LTE), aiming for greater speeds.

4G Wireless System

  • Definition: Fourth generation cellular wireless standards defined by ITU-R as IMT-Advanced.
  • Expectations: Must support 100 Mbps and above for mobile users and high-quality streaming.
  • Technology Legislative:
    • All Internet Protocol (IP) with OFDMA multi-carrier transmission.
    • Must support smooth transitions across networks with high quality of service.
  • Features:
    • Interactive multimedia capability.
    • High-speed, high-capacity, low cost.
    • Global mobility and service portability.
    • Seamless switching with varied QoS requirements.

Applications of 4G Services

  • Ultra high-speed internet access for general web browsing.
  • Data-intensive interactive user services (e.g., online mapping).
  • Multiple User Video Conferencing: Allows interaction among numerous users.
  • Location-Based Services: Weather/traffic updates and proximity to nearby services.
  • Telemedicine: Remote monitoring and advice streaming.
  • HDTV Services: Direct high definition TV streaming.
  • Video on Demand & Real-time Gaming.

LTE and LTE-Advanced

  • LTE: Successor to 3G with significant speed improvements.
    • Downlink speed: 100 Mb/s, Uplink: 50 Mb/s.
    • Real-world speeds: 5-12 Mb/s (down) and 2-5 Mb/s (up).
  • LTE-Advanced: True 4G, meeting ITU standards with:
    • Peak download rates of 3 Gbps and uploads up to 1.5 Gbps.
    • Incorporates new transmission protocols for improved efficiency and capacity.

Comparison of 3G and 4G

Feature3G4G
Frequency Band1.8 - 2.5 GHz2 - 8 GHz
Bandwidth5-20 MHz5-20 MHz
Data RateUp to 2 Mbps20 to 100 Mbps
Access TechnologiesWideband CDMAMulti-carrier OFDM
SwitchingCircuit/PacketIP packet only
Air Link ProtocolsVariousAll IP (IPv6)

Introduction to 5G

  • Definition: Next-gen networks beyond 4G LTE with speeds ranging from 1 Gbps to 10 Gbps expected.
  • Capabilities:
    • Built on 4G LTE foundation with a projected rollout post-2020.
    • Enhancements in latency, capacity, flexibility, and energy efficiency.
  • Technologies:
    • Higher frequency bands (6GHz to 100GHz) for dense network coverage.

Conclusion

  • The evolution from 1G through 5G marks significant advancements in telecommunications, with increasing speed, efficiency, and user capabilities at every generation.