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How Bluetooth Works
in the license free, globally available ISM radio band. The advantage to this band includes worldwide availability and compatibility. A disadvantage to this however, is that the devices must share this band with other RF emitters. This includes automobile security systems, other wireless devices, and other noise sources, such as microwaves. To overcome this challenge, Bluetooth employs a fast frequency hopping scheme and therefore uses shorter packets than other standards within the ISM band. This scheme helps to make Bluetooth communication more robust and more secure. Frequency hopping Frequency hopping is basically jumping from frequency to frequency within the ISM radio band. After a bluetooth device sends or receives a packet, it and the device (or devices) it's communicating with hop to another frequency before the next packet is sent. This scheme offers three advantages: 1. Allows Bluetooth devices to use the entirety of the available ISM band, while never transmitting from a fixed frequency for more than a short period of time. This helps insure that Bluetooth conforms to the ISM restrictions on the transmission quantity per frequency. 2. Ensures that any interference won't last long. Any packet that doesn't arrive safely to its destination can be resent to the next frequency. 3. Provides a base level of security as it's very hard for an eavesdropping device to predict which frequency the Bluetooth devices will use next. The connected devices however, must agree upon the frequency they will use next. The specification in Bluetooth ensures this in two ways. First, it defines a master and slave type relationship between bluetooth devices. Next, it specifies an algorithm that uses device specific information when calculating the frequency hop sequences. A Bluetooth device that operates in master mode can communicate with up to seven devices that are set in slave mode. To each of the slaves, the master Bluetooth device will send its own unique address and the value of its own internal clock. The information sent is then used to calculate the frequency hop sequences. Because the master device and each of the slave devices use the same algorithm with the same initial input, the connected devices will always arrive together at the next frequency that they have agreed upon. As a replacement for cable technology, it's no wonder that Bluetooth devices are usually battery powered, such as wireless mice and battery powered cell phones. To conserve the power, most devices operate in low power. This helps to give Bluetooth devices a range of around 5 - 10 meters. This range is far enough for wireless communication but close enough to avoid drawing too much power from the power source of the device.
Bluetooth Applications |
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10 Benefits Of Bluetooth Below, are 10 benefits and reasons to use Bluetooth technology. 1. Wireless As you probably already know, there are many benefits and advantages to using wireless devices. Along with improving safety as a result of eliminating wires ... Advantages And Disadvantages Bluetooth has a lot to offer with an increasingly difficult market place. Bluetooth helps to bring with it the promise of freedom from the cables and simplicity in networking that has yet to be matched by LAN (Local Area Network). In... Bluetooth And Infared With new electrical devices being produced every day, the problem of connecting things is becoming more and more complex in nature. The system that comprises computers and other electronics makes use of varieties of wires, cables, etc. ... Bluetooth Applications With Bluetooth being very popular with wireless, it's no wonder there are many applications available for the technology. Below, you'll find the applications for Bluetooth. 1. Wireless networking between laptops and desktop ... Bluetooth Definition Bluetooth is a specification for the use of low power radio communications to wireless phones, computers, and other network wireless devices over short distances. The name Bluetooth is actually borrowed from Harald Bluetooth, a Denmark... Bluetooth In Action In the United States, Bluetooth gets absolutely no respect. It is however, becoming more and more common in notebooks, PDAs, and especially cell phones. Bluetooth will provide wireless users a way to transmit small amounts of data over... Bluetooth Technology Intro The technology of Bluetooth is nothing new, but in many respects it can still seem like more of a buzz word rather than an accepted technology. You may see the ads for Bluetooth enabled devices, although you still may be wondering what it... Bluetooth Wireless Networking Bluetooth technology offers three different types of defined ranges, based on output ranges. Class 1 devices are the most powerful, as they can have up to 100 mW of power, with a regular antenna giving them a range of around 130 - 330... Choosing A Bluetooth Headset Creating a good wireless headset for Bluetooth is actually difficult to do. The regular wired headsets are easy to design - with ranging styles. Bluetooth headsets can never be as small or as light as wired headsets, simply because it... How Bluetooth Works Bluetooth devices will normally operate at 2.4 GHZ in the license free, globally available ISM radio band. The advantage to this band includes worldwide availability and compatibility. A disadvantage to this however, is that the devices...
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