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Bluetooth, WiFi and WiMAX are wireless technologies which allow devices to inter-connect and communicate with each other. Radio waves are electomagnetic waves and have different frequencies. These technologies are radio frequencies. Similar to the analogue radio, or FM radio. Bluetooth works on 2.45GHz frequency. WiFi works in two frequency bands 2.4GHz and 5GHz. WiMAX works in two frequency bands, 2 - 11GHz and 10 - 66GHz. See chart below for a comparison of these technologies.
Named after the Danish king, Harold Bluetooth,was the first to emerge, several devices like mobile phones, pdas, headsets, keyboards, mice, medical equipment and even cars now come with this feature. Due to its low cost, manufacturers are willing to implement this technology in most devices. It is designed for short range communications with a range of about 10m. As a result, it consumes less power and are suited for very small battery powered devices and portable devices. Problems associated when devices communicate via infrared or cables are removed. Infrared requires a line of sight, bluetooth only needs to be in reasonable vicinity. As cables are not required, it would be less cumbersome carrying a personal bluetooth device and space would be less cluttered. As bluetooth devices automatically communicate with each other, it requires very little from the user. Bluetooth allows for a wireless Personal Area Network (PAN) with it's short range. See chart below for a comparison of these technologies. For more technical resources and information relating to Bluetooth see the official Bluetooth site.
WiFi or Wireless Fidelity, has a range of about 100m and allows for faster data transfer rate between 10 - 54Mbps. There are three different wireless standards under WiFi, 802.11a, 802.11b and 802.11g. 802.11 being the wireless standard set by The Institue of Electrical and Electronic Engineers (IEEE). WiFi is used to create wireless Local Area Networks (WLAN). The most widely used standard is 802.11b and 802.11g is expexcted to grow rapidly. These two standards are relatively inexpensive and can be found providing wireless connectivity in airports, railway stations, cafes, bars, restaurants and other public areas. The main difference between the two is the speed. 802.11b has data transfer rate of upto 11Mbps and 802.11g has a rate of upto 54Mbps. 802.11g is a relatively new and has yet to be adopted widely. 802.11a is more expensive and as a result it not available for public access. See chart below for a comparison of these technologies.
WiMAX is Worldwide Interoperability for Microwave Access. The IEEE standard for WiMAX is 802.16 and falls under the category of wireless Metropolitan Area Network (WMAN). WiMAX operates on two frequency bands, 2 - 11GHz and 10 - 66GHz and has a range of about 50km with speeds of upto 80Mbps. This enables smaller wireless LANs to be interconnected by WiMAX creating a large wireless MAN. Networking between cities can beachieved without the need for expensive cabling. It is also able to provide high speed wireless broadband access to users. As it can operate in two frequency bands WiMAX can work by line-of-sight and non-line-of-sight. At the 2 - 11GHz frquency range it works by non-line-of-sight, where a computer inside a building communicates with a tower/antenna outside the building. Short frequency transmissions are not easily disrupted by physical obstructions. Higher frequency transmissions are used for non-line-of-sight service. This enables to towers/antennae to communicate with each other over a greater distance. Due to infrastructure and costs involved it would be more suited to provide the backbone services for ISPs and large corporations providing wireless networking and internet access. See chart below for a comparison of these technologies.
| Bluetooth | WiFi (a) | WiFi (b) | WiFi (g) | WiMAX | |
|---|---|---|---|---|---|
| Standard | 802.15 | 802.11a | 802.11b | 802.11g | 802.16 |
| Frequency (GHz) | 2.45 | 5 | 2.4 | 2.4 | 2 - 66 |
| Speed (Mbps) | 0.72 | 54 | 11 | 54 | 80 |
| Range | 10m | 50m | 100m | 100m | 50km |
| Advantages | Low Cost | Speed | Low Cost | Speed | Speed, Range |
| Disadvantages | Range | Cost | Speed | Cost, Range | Cost |