WiMAX has the potential to provide widespread Internet access that can usher in economic growth, better education and healthcare, and improved entertainment services. Examining the technology's global development and deployment a. Score: 5. It is a very powerful but sometimes complicated technique. The book discusses the evolutionary aspects of WiMAX, from the physical to the application layer, including visions from industry, standardization and research communities. Several chapters of the book will present very new and unique information as editors and their respective organizations are involved in ongoing international projects on WiMAX, developing advanced WiMAX techniques.
Key features: Presents evolutionary and visionary developments of WiMAX, motivating and inspiring readers to join and continue the developing work Contains chapters with previously unpublished material, including measurements on real WiMAX equipment and their validation, and introduction of robust header compression in WiMAX, and more Unique results on real WiMAX test-beds Covers WiMAX validation, novel scenarios, applications and business, advanced WiMAX architectures, WiMAX extensions, and WiMAX evolution and future developments Expert authorship with a balanced mix of contributions from highly regarded professionals from top research institutes, industry and academia This book is an invaluable resource for product developers, research and standardization engineers in industry, professors, research scientists and advanced students in academia.
Technology managers and CTOs will also find this book insightful. You not only gain deep insight into the maze of technologies, but also the principles of mobile content-what makes it work, how it's produced, repurposed and delivered securely, and how it integrates with mobile and Internet domains. Learn about the key enablers of a mobile TV service, like smartphones, chipsets, and mobile software. Gain access to a detailed look at the networks deployed worldwide with real-world case studies.
The informative diagrams provide rich visualization of the new technologies, services, and revenue models. Gain understanding of how mobile TV can be made interactive and how it can be delivered seamlessly in multiple markets. Get insight into the growing capabilities of multimedia handsets and software which drives innovative applications.
Author Amitabh Kumar begins with the basics of mobile multimedia and progresses to cover details of technologies, networks, and firmware for mobile TV services. The first part of the text introduces WiMAX networks architecture, physical layer, standard, protocols, security mechanisms, and highly related radio access technologies.
It covers system framework, topology, capacity, mobility management, handoff management, congestion control, medium access control MAC , scheduling, Quality of Service QoS , and WiMAX mesh networks and security.
Enabling easy understanding of key concepts and technologies, the second part presents practical examples and illustrative figures to explain planning techniques and optimization algorithms. The author provides both theoretical and practical information to ensure in-depth, realistic results. Score: 4. The emerging WiMAX system satisfies the growing need for high data-rate applications such as voiceover IP, video conferencing, interactive gaming, and multimedia streaming.
WiMAX deployments not only serve residential and enterprise users but can also be deployed as a backhaul for Wi-Fi hotspots or 3G cellular towers.
This distances than previous technologies such as Wi-Fi. The connection to a second tower often referred to as a standard extension IEEE Typically in a wireless system the radio waves travel from the transmitter to the receiver in a similar manner to light rays — some rays might go straight from the transmitter to the receiver and other will bounce off trees, buildings and cars. These various multipaths, as they are known, can interfere constructively or destructively which causes varying signal power at the receiver.
If the data rate of the channel is low, compared to the time difference between the various multipath components, then a fade can result — deep fades of up to times 30 dB are possible in such systems. If, Fig1: How Wimax works however, a channel is transmitting high rates of data then multipath propagation results in a frequency- 2.
There is line-of-sight service, where a fixed dish antenna points straight at the WiMAX tower from a rooftop or pole. The line-of-sight connection is stronger and more stable, so 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 3. OFDM allows large amounts of digital data to be transmitted over a chunk of spectrum with greater efficiency than existing wireless technologies.
OFDM works by splitting Fig:2 OFDM divide up the spectrum into channels the radio signal into multiple smaller signals that are then transmitted simultaneously at different frequencies Fixed WiMAX serves different users by sharing all the to the receiver. The key to OFDM then another and another and so on. Smart antennas could increase the coverage,range or throughput of a base-station.
In ideal conditions throughput can be increased by a factor of 2 or more. There are three frequency bands defined in the standard, the 2. The mobile standard IEEE It also supports channel sizes between 1. The frequency band used also affects the spacing of basestations. Thus a WiMAX network at 3. The licensed frequencies Smart antennas work differently — they consist of available for broadband wireless access vary from multiple transmit elements and the key to their operation country to country.
However, it is thought that operators is to adjust the amplitude and phase of each element so are also looking especially at lower frequency spectrum as to create constructive interference where there is a for potential WiMAX early deployment due to the larger user, or group of users, and destructive interference cells and attendant lower start-up costs. This results in more of the overall transmit power being received, There is very little harmonisation across the continents reduces multipath and can avoid other sources of and even when common spectrum exists, individual interference If interference becomes a problem a null countries often apply different regulations on how that beam is sent out to reduce the interference.
The spectrum can be used. For example, the 3. This therefore prevents technical 7. WiMAX quality of service features, such as handover, which would be needed in order to support mobility.
The WiMAX Forum is WiMAX, in contrast to Wi-Fi, has an architecture with a appealing to regulators across the world to release base-station that is responsible for processing requests to frequency allocations in the 3. After this, the next major opportunity for spectrum will be when analogue 8. The Wi-Fi decision by the European Commission. All member Alliance has reacted to the security problems with wired states will have to comply with the EU regulations on equivalent privacy WEP by developing Wi-Fi the licence-free use of the — MHz and protected access WPA.
WPA is not yet widely — MHz frequency bands.
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