Worldwide interoperability for microwave access wi max(ieee 802)
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WiMAX (IEEE 802.16) is a wireless technology that provides broadband connections over long distances. It uses licensed spectrum to provide coverage over 50 km at speeds up to 70 Mbps shared among users. The specification has evolved through 802.16, 802.16a, 802.16-2004, and 802.16e-2005 to support both non-line of sight connections and limited mobility. The physical layer uses techniques like OFDM and OFDMA to provide high data rates and efficient use of spectrum. WiMAX has a point-to-multipoint architecture with a central base station and can support applications like video conferencing, media downloads, and web browsing. It offers advantages like low
Worldwide interoperability for microwave access wi max(ieee 802)
- 1. Worldwide Interoperability for Microwave Access WiMAX(IEEE 802.16) by E. Kishore Kumar
- 2. Out line • • • • • • • • • 1.History 2.Specification 3.Architectur 4.Physical layer 5.MAC layer 6.Opetation Network 7.Application 8.Advntage &Disadvantage 9.Conclusion
- 3. Why we need broadband wireless access? • Fill the gap and high data rate wireless LAN and mobile cellular networks. • Provide high-speed mobile data and telecommunications services
- 4. Wireless networks • Wireless PANs (Bluetooth – IEEE 802.15) – very low range – wireless connection to printers etc • Wireless LANs (WiFi – IEEE 802.11) – infrastructure range – home/office networking • Wireless MANs (WiMAX-802.16) – Similar to cellular networks – traditional base station infrastructure systems
- 5. Standards • IEEE 802.16 (2001) – Air Interface for Fixed Broadband Wireless Access System MAC and PHY Specifications for 10 – 66 GHZ (LoS) – One PHY: Single Carrier – Connection-oriented, QoS, Privacy • IEEE 802.16a (January 2003) – Amendment to 802.16, MAC Modifications and Additional PHY Specifications for 2 – 11 GHz (NLoS) – Three PHYs: OFDM, OFDMA, Single Carrier – Additional MAC functions: OFDM and OFDMA PHY support, Mesh topology support, ARQ • IEEE 802.16d (July 2004) – Combines both IEEE 802.16 and 802.16a – Some modifications to the MAC and PHY • IEEE 802.16e (2005) – Amendment to 802.16-2004 – MAC Modifications for limited mobility
- 6. Introduction Coverage range up to 50km and speeds up to 70Mbps(shared among users).
- 7. Specification 802.16 802.16a 802.16-2004 802.16e-2005 Date Completed December 2001 January 2003 June 2004 December 2005 Spectrum 10-66 GHz < 11 GHz < 11 GHz < 6 GHz Operation LOS Non-LOS Non-LOS Non-LOS and Mobile Bit Rate 32-134 Mbps Up to 75 Mbps Up to 75 Mbps Up to 15 Mbps Cell Radius 1-3 miles 3-5 miles 3-5 miles 1-3 miles
- 8. Architecture
- 9. Physical Layer • Five physical layer modes Designation WirelessMAN-SC 802.16e 10 -66 GHz WirelessMAN-SCa 802.16d Applicability Below 11GHz Licensed bands WirelessMAN-OFDM Below 11GHz Licensed bands WirelessMAN-OFDMA Below 11GHz Licensed bands WirelessHUMAN Below 11GHz Licensed-exempt bands
- 10. Orthogonal Frequency Division Multiplexing (OFDM) • Multiplexing technique that divides the channel into multiple orthogonal sub channels • Input data stream is divided into several sub streams of a lower data rate and each sub stream is modulated and simultaneously transmitted on a separate sub channel • High spectral efficiency, resilient to interference, and low multi-path distortion
- 11. Conventional FDM and OFDM
- 12. Orthogonal Frequency Division Multiple Access (OFDMA) • Multiple-access/multiplexing scheme – multiplexing operation of data streams from multiple users – Dynamically assign a subset of sub channels to individual users • Wireless MAN-OFDMA based on scalable OFDMA (SOFDMA) – Support scalable channel bandwidths from 1.25 to 20 MHz
- 13. MAC Layer Service Specific Convergence Sublayer MAC Common Part Sublayer Interface to higher layer protocols, classifies incoming data, etc. Core MAC functions (i.e., scheduling, connection maintenance, fragmentation), QoS control Privacy Sublayer Encryption, authentication, secure key exchange
- 15. Applications • 1. 2. 3. 4. According to WiMax Forum it supports 4 classes of applications: Multi-player Interactive Gaming. Video Conference. Web Browsing and Instant Messaging. Media Content Downloads.
- 16. Advantage • Low cast. • It can support: NLOS(non line of set)&LOS. Mesh Network. Point to Multipoint. Handoff Technique. • Coverage:50Km. • Max Data Rate:70Mpbs.
- 17. Disadvantage • Interference issues. • It is not work proper in weather.
- 18. Features • Use wireless link with microwave or millimeter wave radios. • Use licensed spectrum • Use point-to-multipoint architecture, tower-mounted antennas • Provide broadband and QoS, data transmissions.
- 19. Conclusions • WiMax becomes the dominant Wireless MAN in the world market. • The end-users will have to be extremely easy to install. • Focus is too often on technologies – Subscribers pay for services, not technologies – Broadband capabilities are important, but bandwidth is not the only meter to assess service
- 20. Querries?
- 21. Thank u.
- 22. References • IEEE802.16 • Alcatel White Paper: WiMAX, making ubiquitous high-speed data services a reality • Intel White Paper: Understanding WiMAX and 3G for Portable/Mobile Broadband Wireless • WiMAX Forum: www.wimaxforum.com • http://en.wikipedia.org/wiki/WiMax