Wireless Network Technology

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Wirless PAN

PAN or Personal Area Network describes connectivity of devices in the immediate space of the user. For example, the enablement of communication between a handheld device like a cellular phone and a nearby pc.

Bluetooth

UWB

Wireless LAN

LAN or Local Area Network, for example, an office area.

Wifi

IEEE 802.11 Standards

The following IEEE standards[3] and task groups exist within the IEEE 802.11 working group:

IEEE 802.11 - The original 1 Mbit/s and 2 Mbit/s, 2.4 GHz RF and IR standard (1999)

IEEE 802.11a - 54 Mbit/s, 5 GHz standard (1999, shipping products in 2001)

IEEE 802.11b - Enhancements to 802.11 to support 5.5 and 11 Mbit/s (1999)

IEEE 802.11c - Bridge operation procedures; included in the IEEE 802.1D standard (2001)

IEEE 802.11d - International (country-to-country) roaming extensions (2001)

IEEE 802.11e - Enhancements: QoS, including packet bursting (2005)

IEEE 802.11F - Inter-Access Point Protocol (2003)

IEEE 802.11g - 54 Mbit/s, 2.4 GHz standard (backwards compatible with b) (2003)

IEEE 802.11h - Spectrum Managed 802.11a (5 GHz) for European compatibility (2004)

IEEE 802.11i - Enhanced security (2004)

IEEE 802.11j - Extensions for Japan (2004)

IEEE 802.11k - Radio resource measurement enhancements

IEEE 802.11l - (reserved, typologically unsound)

IEEE 802.11m - Maintenance of the standard; odds and ends.

IEEE 802.11n - Higher throughput improvements

IEEE 802.11o - (reserved, typologically unsound)

IEEE 802.11p - WAVE - Wireless Access for the Vehicular Environment (such as ambulances and passenger cars)

IEEE 802.11q - (reserved, typologically unsound, can be confused with 802.1q VLAN trunking)

IEEE 802.11r - Fast roaming

IEEE 802.11s - ESS Mesh Networking (See: Mesh Standards)

IEEE 802.11T - Wireless Performance Prediction (WPP) - test methods and metrics

IEEE 802.11u - Interworking with non-802 networks (e.g., cellular)

IEEE 802.11v - Wireless network management

IEEE 802.11w - Protected Management Frames

Note - there is no standard or task group named "802.11x". Rather, this term is used informally to denote any current or future 802.11 standard, in cases where further precision is not necessary. (The IEEE 802.1X standard for port-based network access control, is often mistakenly called "802.11x" when used in the context of wireless networks.)

Note - 802.11F and 802.11T are recommendations, not standards and are capitalized as such.

Hardware

Prism

Atheros

Wireless MAN

MAN or Metropolitan Area Network describes networks large enough to service a city.

WiMax

  1. WiMax MAC is very similar to bluetooth - there is a master/slave, AP/client relationship and the MAC layer creates dedicated time slots for clients which can enlarge and constrict. Very different to the contention based CSMA/CA model in WiFi which causes the typical collision and unfairness problems.
  2. Working group in progress for mesh standard for WiMax. If they keep the master/client relationship with central arbitration ... mesh becomes tricky - I've seen the complexity with Bluetooth scatternets where you have to have multiple time sync points - I wonder if they will keep to the same MAC scheme for mesh. Searched all IEEE papers - no one has let this cat out of the bag
  3. WiMax is is mainly defined at the MAC layer, it can run on many different PHY layers although OFDM seems to be the favoured choice at the moment.
  4. There are two frequency bands being defined for WiMax 10 to 66GHz and 802.16a added support for 2 to 11GHz in the unlicensed frequency bands.
  5. Claim distances of 50km but real world tests haven't gone beyond 5 to 8 km
  6. Claim data rates of up to 70 Mbit/s but real world tests show data rates between 500kbit/s and 2 Mbit/s

Download Wimax standard here: Media:802.16-2004.pdf

WiBro

  • Wireless Broadband - a wireless broadband technology developed by the Korean telecommunication industry.
  • In February 2002, the Korean Government allocated 100MHz of spectrum in the 2.3GHz band, and in late 2004 WiBro Phase 1 was standardized by the TTA(Telecommunications Technology Association) of Korea.
  • WiBro will initially offer about 1-3 Mbit/s which can be achieved even is the user is traveling with less then 40 miles per hour (60 km).
  • WiBro is expected to be commercially available in S. Korea by the mid 2006.
  • In Nov. 2004, Intel and LG Electronics agreed to ensure compatability between WiMAX and WiBro.
  • In Sept. 2005, Samsung signed a deal with Srpint Nextel to provide equipment for a WiBro trial in the US.

Wireless WAN

WAN or Wide Area Network describes large networks that typically cover areas as large as an entire country.

Diagram of world technology trends

2.5G

GPRS

General Packet Radio System

EDGE

  • Acronym for Enhanced Data GSM Environment.
  • EDGE is a technology promoted by Ericsson for high speed data transfer over existing GSM networks, without the need to install new equipment -- a software upgrade is sufficient.
  • A network converted to EDGE will allow speeds of up to 384 Kbps or higher, which is 6 times more than what can be reached with an ordinary land line modem.
  • EDGE is a faster version of GSM wireless service.
  • The standard is based on the GSM standard and uses TDMA multiplexing technology.

3G

  • 3G, or third generation, is the generic term used for the next generation of mobile communications systems.
  • Analogue mobile phones were the first generation. Digital marked the second generation. 3G is loosely defined, but generally includes high data speeds, always-on data access, greater voice capacity and is also intended for applications other than voice.
  • The new systems will enhance the services available today and offer multimedia and internet access and the ability to view video footage.
  • The World Administrative Radio Conference assigned 230 megahertz of spectrum at 2 GHz for multimedia 3G networks.
  • These networks must be able to transmit wireless data at 144 kbps at mobile user speeds, 384 kbps at pedestrian user speeds and 2 mbps in fixed locations.
  • Typically they use CDMA techniques and include W-CDMA, CDMA-2000, and TD-SCDMA.
  • Employs wideband frequency carriers.

CDMA

Code Division Multiple Access

CDMA-2000

  • CDMA2000 is a third-generation (3G) wireless technology that is evolved from existing CDMA 2G technology. Its main features are faster data rates, always-on data service, and improved voice network capacity (more people can use each tower at the same time).
  • CDMA2000 will be deployed in at least three phases.
  • The first, 1xRTT, supports up to 144 Kbps packet data speeds. It also doubles voice capacity over previous CDMA networks (IS-95).
  • The second release of 1x, 1xEV-DO, will support data rates up to 2.4 Mbps. It can only be deployed separately from voice networks - in its own spectrum - although devices can be made to access both networks.
  • Such versions have been developed by Ericsson and Qualcomm.
  • The third, 1xEV-DV, supports circuit and packet data rates up to 3-5 Mbps. It fully integrates with 1xRTT voice networks.
  • A possible fourth phase is CDMA2000 3x, although it uses three times as much spectrum.

W-CDMA

  • Wide-band CDMA: a CDMA protocol originated by NTT DoCoMo and now adopted for third-generation use in Europe, Japan and the United States.
  • WCDMA has become the Direct Sequence (DS) mode in the ITU's(International Telecommunications Union) 3G specification, which includes the 1X Multi-Carrier mode (1X MC) and 3X Multi-Carrier mode (3X MC). 1X MC (formerly known as CDMA2000) and 3X MC comprise the 3G upgrade path for carriers already using CDMA (CDMA One).
  • UMTS : universal mobile telephony standard, in the UK a WCDMA system
  • W-CDMA is based on the Direct Spread CDMA technique. Qualcomm collects royalties for both standards. Qualcomm also collects royalties for another standard called TD-SCDMA (Time Division-Synchronous Code Division Multiple Access), which is also based on Qualcomm's CDMA standard.

HSDPA

  • High-Speed Downlink Packet Access or HSDPA is a mobile telephony protocol.
  • Also called 3.5G (or "3½G").
  • High Speed Downlink Packet Access (HSDPA) is a packet-based data service in W-CDMA downlink with data transmission up to 8-10 Mbit/s (and 20 Mbit/s for MIMO systems) over a 5MHz bandwidth in WCDMA downlink. ...
  • Initial deployments and devices will be limited to 1.8 Mbit/s, followed by network upgrades and new devices capable of 3.6 Mbit/s.
  • An upgrade for WCDMA / UMTS networks. It doubles network capacity and increases download data speeds five-fold or more.
  • HSDPA is standardized by the 3GPP in UMTS Release 5.
  • The increase of the downlink speed is achieved by the addition of a new high-speed downlink shared channel as well as by applying different modulation, coding techniques and multiple antennas.

4G

4G is a network of networks, it is a solution looking for a problem. Terminal has to accommodate converged radio networks. “The user wants to google cnn anytime, anywhere at the right cost having all security considered…” (IWS2005, summary of exec round table discussion on 4G).

Also described as an IP Ubiquitous Network.

OFDM