Wireless

WiMAX

WiMAX (Worldwide Interoperability for Microwave Access) is a telecommunications technology aimed at providing wireless data over long distances in a variety of ways, from point-to-point links to full mobile cellular type access. WiMAX operates at higher speeds, over greater distances, and for a greater number of users than Wi-Fi. Because of its higher speed (bandwidth) and falling component prices, it is predicted that WiMAX will soon supplant municipal mesh networks for wireless deployments.

A WiMAX network consists of two main components:

  • A tower that is similar in concept to a cellular telephone tower. A single WiMAX tower can provide coverage to an area as large as 3,000 square miles (7,500 square km).
  • A WiMAX receiver that is connected to a USB port or is built into a laptop or it can be an antena.
Standard Frequency Speed Range
Fixed WiMAX (802.16-2004) 2-11 GHz (3.5 GHz in Europe) 75 Mbps 10 km
Mobile WiMAX (802.16e) 2-6 GHz 30 Mbps 3.5 km

A WiMAX tower station connects directly to the Internet using a high-bandwidth connection, such as a T3 line. A tower can also connect to other WiMAX towers using line-of-sight microwave links.
Mobile WiMAX is currently (April 2012) not available for the European market.

Municipal Wi-Fi(Mesh)

Many municipal governments, often working with service providers, are deploying wireless networks. Most municipal wireless networks use a mesh topology rather than a hub-and-spoke model.
A meshed network has several advantages over a singular wireless router hotspot. Installation is easier and can be less expensive because there are fewer wires. Deployment over a large urban area is faster and more reliable. If a node fails, others in the mesh compensate for it.

Satellite Internet access

Satellite Internet access is Internet access provided through communications satellites. Modern satellite Internet service is typically provided to users through geostationary satellites that can offer high data speeds, with newer satellites achieving downstream data speeds up to 15 Mbps.

Mobile Broadband

Second generation (2G) from 1991:    
Speeds in kbit/s down and up
• GSM CSD 9.6 kbit/s
• CDPD up to 19.2 kbit/s
• GSM GPRS (2.5G) 56–115 kbit/s
• GSM EDGE (2.75G) up to 237 kbit/s
Third generation (3G) from 2001:          
Speeds in Mbit/s down up
• UMTS W-CDMA 0.4 Mbit/s
• UMTS HSPA 14.4 5.8
• UMTS TDD 16 Mbit/s
• CDMA2000 1xRTT 0.3 0.15
• CDMA2000 EV-DO 2.5–4.9 0.15–1.8
• GSM EDGE-Evolution 1.6 0.5
Fourth generation (4G) from 2006:                                           
Speeds in Mbit/s down up
HSPA+ 21–672 5.8–168
Mobile WiMAX (802.16) 37–365 17–376
LTE 100–300 50–75
LTE-Advanced:
• moving at higher speeds 100 Mbit/s
• not moving or moving at lower speeds up to 1000 Mbit/s
MBWA (802.20) 80 Mbit/s

In March 2008, the International Telecommunications Union-Radio communications sector (ITU-R) specified a set of requirements for 4G standards, named the International Mobile Telecommunications Advanced (IMT-Advanced) specification, setting peak speed requirements for 4G service at 100 megabits per second (Mbit/s) for high mobility communication (such as from trains and cars) and 1 gigabit per second (Gbit/s) for low mobility communication (such as pedestrians and stationary users).

Since the first-release versions of Mobile WiMAX and LTE support much less than 1 Gbit/s peak bit rate, they are not fully IMT-Advanced compliant, but are often branded 4G by service providers. On December 6, 2010, ITU-R recognized that these two technologies, as well as other beyond-3G technologies that do not fulfill the IMT-Advanced requirements, could nevertheless be considered “4G”, provided they represent forerunners to IMT-Advanced compliant versions and “a substantial level of improvement in performance and capabilities with respect to the initial third generation systems now deployed”.

Mobile WiMAX Release 2 (also known as WirelessMAN-Advanced or IEEE 802.16m) and LTE Advanced (LTE-A) are IMT-Advanced compliant backwards compatible versions of the above two systems, standardized during the spring 2011, and promising speeds in the order of 1 Gbit/s. Services are expected in 2013.

 

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