Technical
University of Eindhoven – Regulations and Standards for Wireless Communication-0EL70
(Introduction)
This is the first of a
series of posts about WiMax (IEEE 802.16) for the course “Regulations and
Standards for Wireless Communication” of Technical University of Eindhoven, a
regular elective for the Broadband Telecommunications Track of the Master
Program of the Department of Electrical Engineering. We will start with a
technical description of the protocol, then present the standardization process
of it and finally analyze the security issues and the (suggested) uses of it.
Both the so far and the potential future applications and markets will be
described.
WiMax refers to
Worldwide Interoperability for Microwave Access, with a designed offered
bitrate of 30 to 40 Megabits per second (Mbps) initially, which extended to 1
Gigabit per second (Gbps) for fixed stations in 2011. The maximum range is
about 50 kilometers in radius [11]. There have been several updates of the IEEE
802.16 standard. It started in 2001, which was superseded. The first final
version was 802.16-2004 in 2004 and the most recent final version is 802.16m in
2011, while 802.16n and 802.16p are still being processed, as of July 2013 [12].
WiMax has been
suggested as a solution and alternative to several different technologies, such
as LTE (Long Term Evolution) mobile networks (often called 4G), DVB-T (Digital
Video Broadcasting – Terrestrial), commercial triple-play (data, voice and
video) at the last mile of copper today and even as a substitute for backhaul
and backbone links of telecommunications providers [11].
Despite the initial
expectations that had arisen, WiMax has not met those expectations yet,
achieving very small penetration percentages in most countries worldwide
(especially in the “Western World”, ie the European Union, the USA, Japan,
South Korea, Canada and Australia) compared to the GSM/CDMA services and in
general failing to prove as a real alternative to any of the technologies
mentioned above [2]. A comparison of WiMax to similar technologies is shown in
Figure 1.
The efficiency of WiMax
is dramatically affected by the distance between the user and the Base Station
(where the antenna and the transceiver are placed). The theoretical maximum
bitrate is achieved only inside the area of 1 kilometer radius , while for
subscribers at the edge of the range of 50 kilometer, the practical achieved
bitrate indoors has been observed to be 4 Mbps and less [11]. This dictates
that coverage at the top limit of the range faces many problems and does not
correspond to the theoretical technical specifications.
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