articles for telecom engineers

WiMAX (Worldwide Interoperability for Microwave Access) is a new standard that lean on the IEEE’s 802.16 wireless communica­tion standard specifica­tion and it provides ser­vices to faster and wider areas when it is compared with 802.11 group standards (Wi­Fi).Especially it is expected that it will provide wideband inter­net services to the areas that cable and DSL ser­vices cannot reach. WIMAX presents lots of advantages com­pared with other wire­less technologies. WIMAX multi road choice and the property of distribution of delay makes it present a good perfonnance even it is out of the view point of user’ base station.

WIMAX standard uses access demanded access protocol instead of connection based access protocol of 802.11 due to this reason; less data crash is experienced and the current network width can be used more effi­ciently. All communication is checked by the base station. In addi­tion, efficient channel width and adaptive modulation value allow more users to make use of the Internet. WIMAX uses channel width narrow than the width of 20MHz that 802.11 uses, so it does not spend more energy. If the channel that is used is dense, users can stay connected with the use of adaptive modulation. WIMAX also pro­vides high quality service to the customers of wireless internet ser­vice providers.
WIMAX mainly depends on the technologies of OFDM (Orthogonal Frequency Division Multiplexing) and MIMO (Multiple Input Multiple-Output) .With these two developing technologies, the service providers can provide service by using less spectrum to many customers from only one base station. OFDM is the name of base radio technology that is used by Wi-Fi and WIMAX.MIMO is the developed antenna technology that increases WIMAX’s efficiency for 4 times. Third generation and further communication technolo­gies will mostly depend on these OFDM and MIMO technologies.

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