802.11 a/b/g/n Explained
802.11
Protocol
Frequency Modulation Bandwidth Data Rates
(Mb/s)
# MIMO
Streams
Comments
a 5 GHz OFDM 20 MHz 6, 9, 12, 18, 24, 36, 48, 54 1 High frequency reduces effective range
b 2.4 GHz DSSS 20 MHz 1, 2, 5.5, 11 1 Many IT departments are turning off "b" access points
g 2.4 GHz OFDM
&
DSSS
20 MHz 6, 9, 12, 18, 24, 36, 48, 54 1 Only universal module scheme.
Access points auto-adjust rate to minimize packet error rate.
n 2.4 GHz
&
5 GHz
OFDM 20 MHz
&
40 MHz
7.2, 14.4, 21.7, 28.9, 43.3, 57.8, 65, 72.2 (per stream) 4 Must implement MIMO and 40 MHz bandwidth to get maximum data rates (600Mb/s)

802.11 uses latency and rate reduction as a means of addressing increasing packet error rate and increasing range. Thus, the ability to step down through rates is part of the specification to create robust high range networks.

802.11a is used to isolate networks and avoid crowded 2.4GHz spectrum

  • For example – hospitals and patient records

802.11g are energy efficient radios and fully compatible with basic 802.11n networks.

  • Same modulation technique

802.11n is useful for high data throughput applications

  • High definition video, moving Mbytes of data
  • Must implement bonding and Multiple Input Multiple Output (MIMO), to achieve higher rates

Most embedded 802.11n device clients (MRF24WN0MA) are Single-Stream (1x1) devices (i.e. having a single radio chain) in order to preserve battery life.

802.11a/b/g vs 802.11n AP Performance:
As with any wireless technology, as you move farther from the AP, the data rate decreases.
802.11n routers use MIMO reception to increase the range at which the client can transmit at its highest data rates

  • i.e. 802.11n Access Points providing service for older 802.11g clients provide "better g than g"

20th Annual
Microchip MASTERs Conference 2016
Register now - Deadline: July 29

JW Marriott Desert Ridge Resort-Phoenix, AZ

© 2016 Microchip Technology, Inc.
Information contained on this site regarding device applications and the like is provided only for your convenience and may be superseded by updates. It is your responsibility to ensure that your application meets with your specifications. MICROCHIP MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, STATUTORY OR OTHERWISE, RELATED TO THE INFORMATION, INCLUDING BUT NOT LIMITED TO ITS CONDITION, QUALITY, PERFORMANCE, MERCHANTABILITY OR FITNESS FOR PURPOSE. Microchip disclaims all liability arising from this information and its use. Use of Microchip devices in life support and/or safety applications is entirely at the buyer's risk, and the buyer agrees to defend, indemnify and hold harmless Microchip from any and all damages, claims, suits, or expenses resulting from such use. No licenses are conveyed, implicitly or otherwise, under any Microchip intellectual property rights.