Wireless System Overview



Since ancient times, humans have learned to cooperate in order to overcome nature's limitations. There is a growing need to exchange information and services quickly and effortlessly across local, national and now global communities. People want the ability to communicate any time, anywhere in our mobile society.

Wireless technologies make our mobile society possible. Apple's iPod library syncs up with a laptop computer, drivers navigate their cars over uncharted roads, bargain hunters browse online stores, business travelers collaborate 24/7 with associates around the globe. Regardless of the circumstance, people today have an unprecedented level of mobility thanks to any combination of the four common wireless services:

1. WPAN: < 10 m, such as hands-free cell phones
2. WLAN: < 100 m, such as laptop to broadband access
3. WMAN: < xx Kms, such as building-to-building
4. WWAN: cell phones

In general, WLAN provides the most versatile service.  WPAN range is too short and still binds the user to the nearest node.  WMAN is too bulky and expensive to lug around. And WWMAN suffers speed and service charge constraints.

According to industry consensus, WLAN applications consist of three categories that cover many of our day to day mobility requirements:

1. PC Networking: Desktop Computers, Laptops, Routers, Printers, etc.

2. Consumer Electronics: Video Game consoles, Projectors, DVD players, TVs, Set-top boxes, Digital Cameras, Security Cameras, etc.

3. Handheld Devices: Mobile Phones, PDAs, iPods, Video iPods, etc.

In order to ensure high throughput, good range and universal interoperability, IEEE 802.11x standards govern WLAN operations. WLAN and IEEE 802.11x have become synonymous over the years:

  • IEEE 802.11 - The original 1 Mbit/s and 2Mbit/s, 2.4GHz RF and IR standard (1999)
  • IEEE 802.11a - 54Mbit/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 - Enhancement: QoS, including packet bursting (2005)
  • IEEE 802.11f - Inter-Access Point Protocol (2003) Withdrawn February 2006
  • 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 and will not be used)
  • IEEE 802.11m - Maintenance of the standard: odds and ends
  • IEEE 802.11n - Higher throughput improvements
  • IEEE 802.11o - (reserved and will not be used)
  • IEEE 802.11p - WAVE - Wireless Access for the Vehicular Environment (such as ambulances and passengers cars)
  • IEEE 802.11q - (reserved and will not be used, can be confused with 802.1Q VLAN trunking)
  • IEEE 802.11r - Fast roaming
  • IEEE 802.11s - ESS Mesh Networking
  • IEEE 802.11t - Wireless Performance Prediction (WPP) - test methods and metrics
  • IEEE 802.11u - Compatibility with non-802 networks (e.g., cellular)
  • IEEE 802.11v - Wireless network management
  • IEEE 802.11w - Protected Management Frames
  • IEEE 802.11x - (reserved and will not be used)
  • IEEE 802.11y - 3650-3700 Operations in USA