Photo SourceThe current state of the mobile network environment such as public wireless LAN and the cellular phone lines and those problems were considered last time. This time, the focus is applied to “Mobility WiMAX” of the new service that solves these problems, and it introduces the difference with an existing mobile network. The 2nd explains the point of the IEEE standard by which the specification of mobile WiMAX has been decided.
Mobile WiMAX that the business service started in July, 2009 is a new mobile network that did “Cousin removing” of public wireless LAN and the cellular phone line. It becomes “Communication method of the world standard using the micro wave (frequency band of 3GHz-30GHz)” with WiMAX if it translates literally by the one that “World Interoperability for Microwave Access” was abbreviated.
It is a word “Communication (Access)” the hope of you attention here. “Line from the telephone office to the terminal” is indicated if it is said, “Access line” in the world on the network. In a word, WiMAX is a method to achieve the same role as the accomplishment of “[Furettsu] light” of ADSL and NTT on a wireless network.
Actually, there is details of having started WiMAX as a network for not the mobile network but fixed wireless telecommunications (FWA: Fixed Wireless Access). FWA is a method to send and receive data to the antenna set up in the rooftop in the communication tower and the building between terminals. FWA up to maximum transmission speed 156Mbps is an opening in Japan in December, 1998.
WiMAX is wireless MAN(Metropolitan Area Network) standard to achieve this FWA. Institute of Electrical and Electronic Engineers (IEEE) has approved WiMAX as “IEEE 802.16″ in December, 2001.
The bandwidth of 2GHz-11GHz was added back though WiMAX used the bandwidth of improving named 10GHz-66GHz at first. And, the specification named maximum transmission speed 134.4Mbps (occupation bandwidth 28MHz time) or 74.81Mbps (occupation bandwidth 20MHz time) was fixed by the maximum in “IEEE 802.16-2004″ that had been approved in June, 2004 communication distance 48km.
It has corresponded to the handover at 120km per hour.
It reaches up to 4.8km at the speed of 40Mbps or less.
Mobile WiMAX equipped in mobile PC is a wireless network method settled on as derivation standard “IEEE 802.16e” of IEEE 802.16.
Mobility WiMAX is that the maximum difference point of fixation WiMAX of IEEE 802.16 and mobile WiMAX corresponds to the handover (succession) that assumes the movable body of 120km per hour.
In a word, mobile WiMAX is to be able to use it in the train and the car running just like the cellular phone because a surrounding base station communicates one after another in “Hand over” according to the communication situation. There is especially no inconvenience if it thinks the communication distance of the cellular phone is several km though the maximum communication distance of mobile WiMAX is 4.8km and fixation WiMAX 1/10.
It differs according to the occupation bandwidth, and if it is 32Mbps, and it is 20MHz if it is 15Mbps, and 10MHz if the occupation bandwidth is 5MHz, the maximum transmission speed of mobile WiMAX is 75Mbps. In UQ communications that develop mobile WiMAX service domestically, it is sung, “It is 40Mbps or less, and is up-loading, and it is download and 10Mbps or less”. It may be expected that the same degree of the speed as wireless LAN in the office will be obtained as long as the condition is avoided.
Another difference between fixation WiMAX and mobile WiMAX is in the size of the terminal side transmitter-receiver. In fixation WiMAX where long distance/high speed has been achieved by a big transmission output, a considerably big as for terminal side device is needed. On the other hand, the transmitter-receiver of mobile WiMAX is being put in several LSI chips small. An external type is the same degree of the size as USB thumb drive.
Moreover, note PC with built-in controller for mobile WiMAX has been released by each vender since the summer of 2009. The “Let’snote S8/N8″ series of Panasonic especially supports WiMAX by the standard in the consumer model (A corporate model is for subject).
Another strong point is a base station. Wide, mobile WiMAX covers the range where the electric wave reaches and even if the number of base stations is not increased too much, can cover the large range at the cellular phone level. Because it is possible to communicate while it moves by in the train and car, it will be able to be said that it will be a very profitable network for the business user who frequently uses the Web application.
The maintenance of the base station is advanced in domestic various places with steady steps now. I hear that it became possible to use in the government-designated major city and major cities across the country at the end of fiscal year 2009 according to UQ communications.
Note, this is machine translation so ignore the errors.
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