Developments in the wake of GSM have moved via GPRS and EDGE to the 3G technology called WCDMA. The continued progress took the form of new packages of standards in 3GPP that were issued as “releases”. Two important ones were included in release number five at the beginning of 2002, which were called IMS and HSDPA.
IMS (IP Multimedia Subsystem) is a technological architecture for including and offering standardized IP-based services in mobile telephone systems. IMS is intended to link fixed and mobile networks, and to make it possible for end users to use services irrespective of the terminal used (television, telephone, computer) – a service offering often referred to as triple play.
HSDPA (High-Speed Downlink Packet Access) is an upgrade of the WCDMA protocol that substantially increases downlink speeds (from the network to the mobile handset). The basic principle is that all the resources in each cell at any one time can be allocated to one or more users to enable the most efficient possible use.
The next stage was called HSUPA (High-Speed Uplink Packet Access), an uplink upgrade. With uplink and downlink upgrades in place, the acronym could be abbreviated to HSPA, with maximum speeds set at 14.4 Mbps per user. In an attempt to avoid the acronyms altogether, the term “Turbo 3G” was introduced.
For obvious reasons, Ericsson was one of the driving forces in this standardization process. All chips from Ericsson Mobile Platforms since the IMS release have been designed to support IMS. Companies such as HP and IBM also indicated at an early stage that they wanted to play a role in integrating the entire IMS architecture.
WLAN/WI-FI/WIMAX
Another acronym is WLAN (Wireless Local Area Network), a collective term for various types of local wireless networks based on radio waves in frequency ranges for which licenses are not required, most frequently the 2.4 GHz band, and on radio access technology OFDM. With WLAN links, users can move freely within a restricted area and enjoy unbroken contact with a network.
The most common type of WLAN involves the IEEE 802.11 standard family, which is used to link computers, IP-based telephones, media players and other peripherals to a central access point. Wi-Fi became a trade name for this WLAN family; a trade organization called the Wi-Fi Alliance was founded in 1999 to define the 802.11 technology and issue certificates guaranteeing that all products would work together.
Another family of standards for WLAN is IEEE 802.16, where a version called WiMAX (Worldwide Interoperability for Microwave Access) has turned out to be particularly important. WiMAX was promoted as unique among wireless standards because it did not specify any type of radio and allowed both FDD and TDD with almost any carrier across the entire frequency spectrum from 1.75 MHz to 28 MHz.
“4G WAR” STARTED
In retrospect, the starting shot in the “4G war” can be traced to the foundation of an organization called the WiMAX Forum in June 2001, just when the brutal effect of the telecommunications crisis was beginning to become visible. Nokia was one of the founders, joined the following year by Intel, which became one of the most forceful proponents. WiMAX began to be described as an alternative to WCDMA-based systems, and Intel in particular announced that it was going to enter the broadband contest using WiMAX.
Its advocates pointed in particular to WiMAX’s long range of up to 50 kilometers, which was said to make it suitable for wireless broadband connections in rural areas and environments where fiber-optic networks had not generally been rolled out. Sean Maloney, head of Intel’s communications group, gave interviews in which he explained how WiMAX would provide internet access to a further 5 billion people.
Intel also took action in Sweden. A test of its WiMAX technology for wireless broadband in 28 households in Skellefteå in the north of Sweden was said to yield promising results. The end-user equipment was easy to install, although it was still too expensive.
Author: Svenolof Karlsson & Anders Lugn