13-08-2014, 03:36 PM
BLUETOOTH TECHNOLOGY
[attachment=66621]
INTRODUCTION:
During the past two decades, the advancement in microelectronics and VLSI technology dipped down the cost of many consumer electronic products to a level which was affordable for the common man. The first quarter of 2001, saw the vending of about 32.5 million PCs. The sale of cellular phones is predicted to reach 1 billion in 2005. With increase in the number of electronic devices, comes in the need of connecting them together for maximum interoperability and utilization. These devices connect with each other using a variety of wires, cables, radio signals and infrared light beams, and an even greater variety of connectors, plugs and protocols. Bluetooth is devised to replace these cables.
Bluetooth is a global standard for wireless connectivity. Bluetooth technology facilitates the replacement of the cables used to connect one device to another, with one universal short-range radio link operating in the unlicensed 2.45 GHz ISM band. The main objectives of Bluetooth technology can be described as follows,
Cable replacement: Getting rid of the various types of cables and wires required for interconnectivity between various devices would enable the lay man to use all electronic devices without wasting time and money.
Small size: the Bluetooth device is very small so that it can be attached to any device required like the cell phones without adding much to the weight of the system.
Low cost: Bluetooth is aimed to be a low cost device approximately $5 in the near future.
Low power: The utilization of power is very less (within 100 mW) as it is short range equipment and so it facilitates the use of small batteries for its usage.
Besides the characteristics mentioned above, Bluetooth can imitate a universal bridge to attach the existing data networks, and also as a mechanism for forming ad-hoc networks. Designed to operate in noisy frequency environments, the Bluetooth radio uses a fast acknowledgement and frequency hopping scheme to make the link robust.
HISTORY:
In 1994, Ericsson in Sweden launched an initiative to study a low-power, low-cost radio interface between mobile phones and their accessories. After three years, In 1997, Ericsson approached various manufacturers of mobile electronic devices to discuss the development and promotion of this short range wireless radio link as alone this phenomenon could not be implemented.
Thus in 1998, Ericsson, IBM, Intel, Toshiba and NOKIA formed the Special Interest Group (SIG) for the promotion and development of BLUETOOTH technology. The first Bluetooth silicon was also ready in 1998. As we can see that the SIG included two market leaders in mobile telephony, two in laptop computing and one in digital signal processing technology. The biggies being in the game gave an impetus to thousands of companies to join hands with the SIG for the endorsement and expansion of this technology.
One would wonder how Bluetooth got its name. It has an interesting heritage. Bluetooth is named after the 10th century Viking King Harald Blatand (Blatand meaning Bluetooth). He was instrumental in uniting the countries in the Baltic region like Sweden, Denmark, Norway and thus emerging as a powerful force. Bluetooth aims at uniting the computing and telecommunication world and so achieving the same greatness.
Baseband:
The Baseband is the physical layer of the Bluetooth. It manages physical channels and links apart from other services like error correction, data whitening, hop selection and Bluetooth security. As mentioned previously, the basic radio is a hybrid spread spectrum radio. Typically, the radio operates in a frequency-hopping manner in which the 2.4GHz ISM band is broken into 79 1MHz channels that the radio randomly hops through while transmitting and receiving data. A piconet is formed when one Bluetooth radio connects to another Bluetooth radio.
Working of Bluetooth technology
Bluetooth is a short-range wireless technology used to create PANs (Personal Area Networks) among your devices and with other nearby devices. Bluetooth requires that a low-cost transceiver chip be included in each device. The transceiver transmits and receives in a previously unused frequency band of 2.45 GHz that is available globally (with some variation of bandwidth in different countries). In addition to data, up to three voice channels are available. Each device has a unique 48-bit address from the IEEE 802 standard. Connections can be point-to-point or multipoint. The maximum range is 10 meters. Data can be exchanged at a rate of 1 megabit per second (up to 2 Mbps in the second generation of the technology). A frequency hop scheme allows devices to communicate even in areas with a great deal of electromagnetic interference. Built-in encryption and verification is provided.
Bluetooth is essentially a networking standard that works at two levels:
• It provides agreement at the physical level -- Bluetooth is a radio-frequency standard.
• It provides agreement at the protocol level, where products have to agree on when bits are sent, how many will be sent at a time, and how the parties in a conversation can be sure that the message received is the same as the message sent
A number of devices may already take advantage of this same radio-frequency band. Baby monitors, garage-door openers and the newest generation of cordless phones all make use of frequencies in the ISM band. Making sure that Bluetooth and these other devices don't interfere with one another has been a crucial part of the design process.
One of the ways Bluetooth devices avoid interfering with other systems is by sending out very weak signals of about 1 milliwatt. By comparison, the most powerful cell phones can transmit a signal of 3 watts. The low power limits the range of a Bluetooth device to about 10 meters (32 feet), cutting the chances of interference between your computer system and your portable telephone or television or any other device. Even with the low power, Bluetooth doesn't require line of sight between communicating devices. The walls in your house won't stop a Bluetooth signal, making the standard useful for controlling several devices in different rooms.
Bluetooth can connect up to eight devices simultaneously. With all of those devices in the same 10-meter (32-feet) radius, you might think they'd interfere with one another, but it's unlikely. Bluetooth uses a technique called spread-spectrum frequency hopping that makes it rare for more than one device to be transmitting on the same frequency at the same time. In this technique, a device will use 79 individual, randomly chosen frequencies within a designated range, changing from one to another on a regular basis.
ADVANTAGES
Presentations
Setting up power point presentations, for example, would no longer require a spaghetti- like tangle of cables between projectors, laptop and printer. You would simply place the laptop near the projector, turn them on, and wait a few moments for them to communicate the necessary operating parameters.
Synchronizing Data
Automatic synchronization can be a real time saver. When you're finished adding information to your palmtop at home, all you have to do is walk by your cubicle at work to get the files uploaded to the desktop PC. When you leave the office, any new files added to your desktop PC are automatically copied to your palmtop. With synchronization there's no longer any confusion about which file is on which machine.
CONCLUSION
Bluetooth technology is a short-range wireless specification aimed at simplifying communications among Internet devices and between devices and the Internet. In conclusion it can be said that Bluetooth refers not only to a technology but also to a standard and a specification. The take off that Bluetooth has taken is remarkable, capturing the attention and money of major corporations throughout the world. If it can live up to its expectations and satiate the needs of a global market in an easy and inexpensive way , it promises to become a uniting force in the wireless world and endow us with the freedom of mobility like never before.
[attachment=66621]
INTRODUCTION:
During the past two decades, the advancement in microelectronics and VLSI technology dipped down the cost of many consumer electronic products to a level which was affordable for the common man. The first quarter of 2001, saw the vending of about 32.5 million PCs. The sale of cellular phones is predicted to reach 1 billion in 2005. With increase in the number of electronic devices, comes in the need of connecting them together for maximum interoperability and utilization. These devices connect with each other using a variety of wires, cables, radio signals and infrared light beams, and an even greater variety of connectors, plugs and protocols. Bluetooth is devised to replace these cables.
Bluetooth is a global standard for wireless connectivity. Bluetooth technology facilitates the replacement of the cables used to connect one device to another, with one universal short-range radio link operating in the unlicensed 2.45 GHz ISM band. The main objectives of Bluetooth technology can be described as follows,
Cable replacement: Getting rid of the various types of cables and wires required for interconnectivity between various devices would enable the lay man to use all electronic devices without wasting time and money.
Small size: the Bluetooth device is very small so that it can be attached to any device required like the cell phones without adding much to the weight of the system.
Low cost: Bluetooth is aimed to be a low cost device approximately $5 in the near future.
Low power: The utilization of power is very less (within 100 mW) as it is short range equipment and so it facilitates the use of small batteries for its usage.
Besides the characteristics mentioned above, Bluetooth can imitate a universal bridge to attach the existing data networks, and also as a mechanism for forming ad-hoc networks. Designed to operate in noisy frequency environments, the Bluetooth radio uses a fast acknowledgement and frequency hopping scheme to make the link robust.
HISTORY:
In 1994, Ericsson in Sweden launched an initiative to study a low-power, low-cost radio interface between mobile phones and their accessories. After three years, In 1997, Ericsson approached various manufacturers of mobile electronic devices to discuss the development and promotion of this short range wireless radio link as alone this phenomenon could not be implemented.
Thus in 1998, Ericsson, IBM, Intel, Toshiba and NOKIA formed the Special Interest Group (SIG) for the promotion and development of BLUETOOTH technology. The first Bluetooth silicon was also ready in 1998. As we can see that the SIG included two market leaders in mobile telephony, two in laptop computing and one in digital signal processing technology. The biggies being in the game gave an impetus to thousands of companies to join hands with the SIG for the endorsement and expansion of this technology.
One would wonder how Bluetooth got its name. It has an interesting heritage. Bluetooth is named after the 10th century Viking King Harald Blatand (Blatand meaning Bluetooth). He was instrumental in uniting the countries in the Baltic region like Sweden, Denmark, Norway and thus emerging as a powerful force. Bluetooth aims at uniting the computing and telecommunication world and so achieving the same greatness.
Baseband:
The Baseband is the physical layer of the Bluetooth. It manages physical channels and links apart from other services like error correction, data whitening, hop selection and Bluetooth security. As mentioned previously, the basic radio is a hybrid spread spectrum radio. Typically, the radio operates in a frequency-hopping manner in which the 2.4GHz ISM band is broken into 79 1MHz channels that the radio randomly hops through while transmitting and receiving data. A piconet is formed when one Bluetooth radio connects to another Bluetooth radio.
Working of Bluetooth technology
Bluetooth is a short-range wireless technology used to create PANs (Personal Area Networks) among your devices and with other nearby devices. Bluetooth requires that a low-cost transceiver chip be included in each device. The transceiver transmits and receives in a previously unused frequency band of 2.45 GHz that is available globally (with some variation of bandwidth in different countries). In addition to data, up to three voice channels are available. Each device has a unique 48-bit address from the IEEE 802 standard. Connections can be point-to-point or multipoint. The maximum range is 10 meters. Data can be exchanged at a rate of 1 megabit per second (up to 2 Mbps in the second generation of the technology). A frequency hop scheme allows devices to communicate even in areas with a great deal of electromagnetic interference. Built-in encryption and verification is provided.
Bluetooth is essentially a networking standard that works at two levels:
• It provides agreement at the physical level -- Bluetooth is a radio-frequency standard.
• It provides agreement at the protocol level, where products have to agree on when bits are sent, how many will be sent at a time, and how the parties in a conversation can be sure that the message received is the same as the message sent
A number of devices may already take advantage of this same radio-frequency band. Baby monitors, garage-door openers and the newest generation of cordless phones all make use of frequencies in the ISM band. Making sure that Bluetooth and these other devices don't interfere with one another has been a crucial part of the design process.
One of the ways Bluetooth devices avoid interfering with other systems is by sending out very weak signals of about 1 milliwatt. By comparison, the most powerful cell phones can transmit a signal of 3 watts. The low power limits the range of a Bluetooth device to about 10 meters (32 feet), cutting the chances of interference between your computer system and your portable telephone or television or any other device. Even with the low power, Bluetooth doesn't require line of sight between communicating devices. The walls in your house won't stop a Bluetooth signal, making the standard useful for controlling several devices in different rooms.
Bluetooth can connect up to eight devices simultaneously. With all of those devices in the same 10-meter (32-feet) radius, you might think they'd interfere with one another, but it's unlikely. Bluetooth uses a technique called spread-spectrum frequency hopping that makes it rare for more than one device to be transmitting on the same frequency at the same time. In this technique, a device will use 79 individual, randomly chosen frequencies within a designated range, changing from one to another on a regular basis.
ADVANTAGES
Presentations
Setting up power point presentations, for example, would no longer require a spaghetti- like tangle of cables between projectors, laptop and printer. You would simply place the laptop near the projector, turn them on, and wait a few moments for them to communicate the necessary operating parameters.
Synchronizing Data
Automatic synchronization can be a real time saver. When you're finished adding information to your palmtop at home, all you have to do is walk by your cubicle at work to get the files uploaded to the desktop PC. When you leave the office, any new files added to your desktop PC are automatically copied to your palmtop. With synchronization there's no longer any confusion about which file is on which machine.
CONCLUSION
Bluetooth technology is a short-range wireless specification aimed at simplifying communications among Internet devices and between devices and the Internet. In conclusion it can be said that Bluetooth refers not only to a technology but also to a standard and a specification. The take off that Bluetooth has taken is remarkable, capturing the attention and money of major corporations throughout the world. If it can live up to its expectations and satiate the needs of a global market in an easy and inexpensive way , it promises to become a uniting force in the wireless world and endow us with the freedom of mobility like never before.