The new 802.11n standard uses various new technologies to give Wi-Fi more speed and range. The most notable among these is the MIMO (multiple input, multiple output), which uses multiple antennas and advanced signal processing to move a number of data streams from one place to another. MIMO can simultaneously transmit three streams of data and receive two, allowing more data to be transmitted in the same period of time. This technique increases the range, or the distance over which data can be transmitted.
The second technology incorporated into 802.11n is channel bonding, which uses two separate non-overlapping channels at the same time to transmit data. Conventional wireless technologies are limited to transmitting over one of several 20-MHz channels. The channel bonding technique combines two adjacent 20-MHz channels into a single 40-MHz channel. The technique more than doubles the channel bandwidth and increases the amount of data that can be transmitted.
A third technology in 802.11n is packet aggregation, which ensures that more data can be stuffed into each transmitted packet. However, real-time applications do not benefit from this technology.
The new and improved 802.11n wireless standard provides users with significantly greater speed and range.
- Speed: 802.11g products, having a theoretical maximum throughput speed of 54 Mbit/sec, typically provide real-world speeds of 22 Mbit/sec to 24 Mbit/sec. As against this, 802.11n based equipment provide real-world speeds of 100 Mbit/sec to 140 Mbit/sec
- Range: Range is harder to quantify because it’s affected by many variables, such as barriers that could block the signal. However, 802.11n based equipment typically deliver more than twice the range of 802.11g equipment, at any given throughput speed.
The new 802.11n standard addresses the throughput issues faced by users; opening the way to newer applications, such as wireless voice over IP, video conferencing and wireless IP Surveillance.
