Evolution of Wireless Standards and Technologies

Sep 21, 2024

Lecture on Wireless Networks and Standards

Introduction

  • Wireless networks are ubiquitous in homes, businesses, restaurants, and conference rooms.
  • Standards for these networks come from the IEEE LAN/MAN Standards Committee, specifically the 802.11 standard.
  • Often referred to as Wi-Fi, a trademark of the Wi-Fi Alliance which tests device interoperability.

Overview of Wireless Standards

802.11a

  • Released: October 1999
  • Frequency: 5 GHz
  • Speed: Up to 54 Mbps
  • Characteristics: Limited range due to higher frequency absorption.
  • Current Use: Rare, usually upgraded to newer standards.

802.11b

  • Released: Same time as 802.11a
  • Frequency: 2.4 GHz
  • Speed: Up to 11 Mbps
  • Characteristics: Better range due to frequency bouncing off objects.
  • Challenges: Frequency conflicts with other devices like baby monitors and Bluetooth.

802.11g

  • Released: June 2003
  • Frequency: 2.4 GHz
  • Speed: Up to 54 Mbps
  • Characteristics: Backwards compatible with 802.11b.
  • Challenges: Same frequency conflicts as 802.11b.

802.11n (Wi-Fi 4)

  • Released: 2009
  • Frequencies: 2.4 GHz and 5 GHz
  • Speed: Up to 600 Mbps (with 4 antennas)
  • Features: MIMO technology.

802.11ac (Wi-Fi 5)

  • Released: January 2014
  • Frequency: 5 GHz
  • Speed: Theoretical max of 6.9 Gbps
  • Features: Multi-user MIMO, 160 MHz channel bandwidth.

802.11ax (Wi-Fi 6)

  • Released: February 2021
  • Frequencies: 2.4 GHz and 5 GHz
  • Speed: Up to 9.6 Gbps
  • Features: OFDMA, suitable for high-density environments.

Network Setup and Regulatory Considerations

  • Range: 40-50 meters with built-in antennas.
  • Long-range networks require directional antennas and adherence to regulations.
  • Regulatory concerns: Frequency usage, signal strength limits for indoor and outdoor use.
  • Importance of compliance with local and federal regulations.

RFID and NFC Technologies

RFID (Radio Frequency Identification)

  • Used in access badges, inventory tracking, and pet identification.
  • Types: Passive (no battery) and active (powered).

NFC (Near Field Communication)

  • Used in mobile devices for payments, pairing Bluetooth, and as access cards.

The lecture covers the evolution of wireless standards from 802.11a to Wi-Fi 6, highlighting key features, usage scenarios, and the importance of regulatory compliance. Additionally, it touches on RFID and NFC technologies as part of the broader wireless communication landscape.