WIMAX Worldwide Interoperability for Microwave Access IEEE 802

WIMAX Worldwide Interoperability for Microwave Access

IEEE 802. 16 Specifications § § § Range - 30 -mile (50 -km) radius from base station Speed - 70 megabits per second Line-of-sight not needed between user and base station Frequency bands - 2 to 11 GHz and 10 to 66 GHz (licensed and unlicensed bands) Defines both the MAC and PHY layers and allows multiple PHY-layer specifications.

INTRODUCTION TO WIMAX § WIMAX also goes by the IEEE name 802. 16 e, is a newer standard of wireless networking designed to provide the high speed internet access to the end user. § WIMAX is designed to provide (MAN) Metropolitan Area Access to homes and businesses. Prepared by: xulcurnain sikandar

COVERAGE AREA AND SPEED IN CASE OF WIMAX § WIMAX can provide broadband wireless access of 30 miles for fixed stations and 3 -10 miles for mobile stations. § In contrast WIFI/802. 11 WLAN is limited in most cases to only 30 – 100 meters. § WIMAX should be able to handle up to 70 megabits per second.

§ § § USAGE OF FREQUENCY IN WIMAX operates on both licensed and non licensed frequencies. As many people have given up their "land lines" in favor of cell phones, WIMAX could replace cable and DSL services, providing universal Internet access just about anywhere you go. WIMAX will also be as painless as Wi-Fi -- turning your computer on will automatically connect you to the closest available WIMAX antenna.

§ § In practical terms, WIMAX would operate similar to Wi. Fi but at higher speeds, over greater distances and for a greater number of users. WIMAX could potentially erase the suburban and rural blackout areas that currently have no broadband Internet access because phone and cable companies have not yet run the necessary wires to those remote locations.

§ § § WORKING STRUCTURE OF WIMAX SYSTEM A WIMAX system consists of two parts: WIMAX Tower: A WIMAX tower is similar in concept to a cell-phone tower. A single WIMAX tower can provide coverage to a very large area -- as big as 3, 000 square miles. A WIMAX receiver – The receiver and antenna could be a small box or PCMCIA card, or they could be built into a laptop the way Wi-Fi access is today.

§ § A WIMAX tower station can connect directly to the Internet using a high-bandwidth, wired connection (for example, a T 3 line). It can also connect to another WIMAX tower using a line -of-sight, microwave link. This connection to a second tower (often referred to as a backhaul), along with the ability of a single tower to cover up to 3, 000 square miles. Due to this reason, WIMAX provides coverage to remote rural areas.

TWO MAIN TYPES OF SERVICES PROVIDED BY WIMAX § § § Non-line-of-sight service: In this type of service, a small antenna on computer connects to the tower. Here WIMAX uses lower frequency range of 2 – 11 GHz. Advantages: Lower-wavelength transmissions are not as easily interrupted by physical obstructions. They are better able to diffract, or bend, around obstacles.

§ § § § Line-of-sight service In this case a fixed dish antenna points straight at the WIMAX tower from a rooftop or pole. Advantages of Line-of-sight service: The line-of-sight connection is stronger and more stable It's able to send a lot of data with fewer errors. Line-of-sight transmissions use higher frequencies, with ranges reaching a possible 66 GHz. At higher frequencies, there is less interference and lots more bandwidth.

§ § Through the stronger line-of-sight antennas, the WIMAX transmitting station would send data to WIMAX-enabled computers or routers set up within the transmitter's 30 mile radius. This is what allows WIMAX to achieve its maximum range.

WIMAX Coverage and Speed § § WIMAX operates on the same general principles as Wi. Fi -it sends data from one computer to another via radio signals. A computer equipped with WIMAX would receive data from the WIMAX transmitting station by using encrypted data keys to prevent unauthorized users from stealing access.

§ § The fastest Wi-Fi connection can transmit up to 54 megabits per second under optimal conditions. WIMAX should be able to handle up to 70 megabits per second.

Difference between WIMAX and Wi-Fi § § § The biggest difference between WIMAX and Wi-Fi is not the speed but it is distance. Wi-Fi's range is about 100 feet (30 m). WIMAX will cover a radius of 30 miles. The increased range is due to the frequencies used and the power of the transmitter. Of course, at that distance, terrain, weather and large buildings will act to reduce the maximum range in some circumstances, but the potential is there to cover huge tracts of land.

Comparison according to coverage area § § The biggest difference between Wi-Fi and WIMAX is the range. For non-line of sight, the range is 25 square miles (65 square kilometers). For line of sight between the transmission point and receiving antenna, the range jumps up to 2, 800 square miles (9, 300 square kilometers). Wi-Fi can work well in localized locations; the routers used for the connections do not have a tremendous amount of range. In most cases, 300 feet (approximately 100 meters) is about the limit of the technology.

Operation in term of frequency § § Wi-Fi, like cordless phones, operates in unlicensed spectrum. There are some implementations of WIMAX for unlicensed spectrum but most WIMAX development has been done on radios which operate on frequencies whose use requires a license.

Bandwidth Comparison § § WIMAX provides a higher speed wireless internet access. WIMAX can be running at a speed up to 70 Mbit/s. The goal for the long term development of WIMAX is to achieve 100 Mbit/s mobile and 1 Gbit/s fixed-nomadic bandwidth and can be expected to be one of the most widely used wireless internet access technologies in the future.

§ § Comparison in terms of standards WIMAX uses IEEE 802. 16 standard and provides the last mile of (MAN) Metropolitan Area high speed internet access, so it is often called 802. 16 while Wi-Fi is wireless Local Area Network which uses 802. 11 standards. Security comparison WIMAX provides multi-media and telecommunications services, it is securer as compared to Wi-Fi.