WiMax

Introduction to WiMax and Broadband Access Technologies:

Introduction to WiMax and Broadband Access Technologies Ziamohiuddin Mcs 3946

What is WiMax?:

What is WiMax? WiMax (Worldwide Interoperability for Microwave Access) is a standards-based technology enabling the delivery of last mile wireless broadband access as an alternative to cable and DSL. The technology is specified by the Institute of Electrical and Electronics Engineers Inc., as the IEEE 802.16 standard.

WiMax Technology:

WiMax Technology WiMAX is expected to provide fixed , nomadic, portable and, eventually, mobile wireless broadband connectivity without the need for direct line-of-sight (LOS) with a base station. In a typical cell radius deployment of three to ten kilometers, WiMAX Forum Certified™ systems can be expected to deliver capacity of up to 40 Mbps per channel, for fixed and portable access applications. Mobile network deployments are expected to provide up to 15 Mbps of capacity within a typical cell radius deployment of up to three kilometers.

Why is it Interesting?:

Why is it Interesting? Simultaneously support hundreds of businesses with T-1 speed connectivity and thousands of homes with DSL speed connectivity. Promise of potential low cost and flexibility in building broadband networks. Scalability, as extra channels and base stations can be added incrementally as bandwidth demand grows. Support for both voice and video as well as Internet data. Semiconductor vendors envisage WiMax-enabled chips appearing in PCs in 2006 and in notebook computers and PDAs by 2007

WiMax Standards:

WiMax Standards 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

WiMax is well suited to offer both fixed and mobile access:

WiMax is well suited to offer both fixed and mobile access

Slide 7:

Network Architecture

How WiMax Works:

How WiMax Works WiMax can provide 2 forms of wireless service: - Non-LOS, Wi-Fi sort of service, where a small antenna on a computer connects to the tower. Uses lower frequency range (2 to 11 GHz). - LOS, where a fixed antenna points straight at the WiMax tower from a rooftop or pole. The LOS connection is stronger and more stable, so it is able to send a lot of data with fewer errors. Uses higher frequencies, with ranges reaching a possible 66 GHz. Through stronger LOS antennas, WiMax transmitting stations would send data to WiMax enabled computers or routers set up within 30 (3,600 square miles of coverage) mile radius.

Technical Similarities and Differences Between Licensed and License-Exempt Bands:

Technical Similarities and Differences Between Licensed and License-Exempt Bands Both solutions are based on IEEE 802.16-2004 standard, which uses OFDM in the physical (PHY) layer. OFDM provides benefits such as increased SNR of subscriber stations and improved resiliency to multi-path interference. For creating bi-directional channels for uplink and downlink, licensed solutions use FDD while license exempt solutions use TDD.

OFDM:

OFDM

Time Division Duplexing (TDD):

Time Division Duplexing (TDD) Description A duplexing technique used in license-exempt solutions, which uses a single channel for uplink and downlink. Advantages Enhanced flexibility, easier to pair with smart antenna technologies, asymmetrical. Disadvantages Cannot transmit and receive at the same time. Usage “ Bursty ”, asymmetrical data applications, environments with varying traffic patterns, where RF efficiency is more important than cost.

TDD:

TDD

Frequency Division Duplexing (FDD):

Frequency Division Duplexing (FDD) Description A duplexing technique used in licensed solutions that uses a pair of spectrum channels, one for the uplink and another for the downlink. Advantages Proven technology for voice, designed for symmetrical traffic, does not require guard time. Disadvantages Cannot be deployed where spectrum is unpaired, spectrum is usually licensed, higher cost associated with spectrum purchase. Usage Environments with predictable traffic patterns, where equipment costs are more important than RF efficiency.

FDD:

FDD

WiMax Applications:

WiMax Applications According to WiMax Forum it supports 5 classes of applications: Multi-player Interactive Gaming. VOIP and Video Conference Streaming Media Web Browsing and Instant Messaging Media Content Downloads

Characteristics of WiMax Frequency Ranges:

10 - 66 GHz Short wavelength Line-of-sight (LOS) required Negligible multipath 2 – 11 GHz Longer wavelength Improved range and in-building penetration LOS not required Multipath effects may be significant Characteristics of WiMax Frequency Ranges

End of Presentation:

End of Presentation Thank You.