Sometimes 802.11g is referred as “G”. It is an IEEE wireless standard which was an improvement on 802.11a and 802.11b and came out in June 2002. Like the other version of Wi-Fi standards, “G” supports WLAN (Wireless LAN) communication between host computers, routers, and other consumer devices.

Features of 802.11g

Speed

Theoretically, “G” can reach a data transfer rate of 54 Mbps, which is same as the earlier standard 802.11a but higher than more widely used standard 802.11b, which allowed a maximum transfer rate 11 Mbps.

Like many other methods of networking, “G” cannot achieve the maximum data transfer rate in practice. Considering the network bandwidth used by overheads of the communication protocol, it can reach a data transfer rate between 24 Mbps and 31 Mbps.

Modulation

“G” standard uses a modulation scheme called orthogonal frequency-division multiplexing (OFDM). OFDM was first introduced with 802.11a.

OFDM is a method to manipulate digital signal in which a single data stream splits into separate narrowband channels. All these channels operate at different frequencies which helps in reducing interference and crosstalk.

Frequency

“G” can operate 14 channels of communication. A channel refers to a physical transmission medium. For instance, in case of a wired network, a wire would be a channel.

A radio channel refers merely to a logical connection which operates on a specific band of frequencies.  Each of these channels transmits radio waves at frequencies between 2.412 GHz and 2.484 GHz (the same band as 802.11b).

Compatibility with 802.11b

Before the introduction of 802.11g, most networks employed 802.11b standard which allowed speeds up to 11 Mbps. The modulation method in 802.11g was updated to OFDM which reduced interference and crosstalk while increased the network speed up to 54 Mbps.

To ensure backward compatibility, “G” operated at the same frequency band as 802.11b. An access point compatible with 802.11b could be upgraded to 802.11g by updating the firmware.

Home networking with “G”

At the time of the release of” G”, Wi-Fi was being adopted widely for use in homes. With 802.11g combining the best elements of 802.11a and 802.11b, a large number of laptop brands were equipped with hardware (Wi-Fi radios) that supported 802.11g.

Many home networks today still use”G” routers. At 54Mbps, these routers can handle high-speed connections used for video streaming and online gaming. These wifi routers are also inexpensive and readily available on retail.

Problems with 802.11g

The frequency spectrum employed by 802.11g (2.4 GHz to 2.5 GHz) is shared with different household appliances and medical devices.

So, like 802.11b,”G” devices also suffer interference from other devices operating in the same band, such as wireless keyboards. 802.11g can reach a speed of 54 Mbps (theoretically) which is considered high speed for a single user.

However, when multiple users are connected, the speed decreases drastically and hard to work with. So setting up large networks with 802.11g is a challenge.