These can be extremely useful for early adopters whose products appear before main testing programs are underway, or for clearing up any inherent misunderstanding of the specification, especially at the profile level (see Bluetooth. Wikipedia, the free encyclopaedia, Feb. 12, 2007). RF performance of a radio is sensitive to the manufacturing process, often taking it out of specification. The Bluetooth core specification provides a test mode enabling efficient production line testing, aiding test equipment manufacturers to produce production test equipment compatible with all Bluetooth devices.
The Bluetooth specification allows inter device communications to be secure through the use of encrypted links, which can be turned on and off as required. Link keys are shared between required devices and to be interoperable in this encrypted process, devices must possess the correct link keys (see Bluetooth. Wikipedia, the free encyclopaedia, Feb. 12, 2007). How Bluetooth applies to wireless technology? If Bluetooth units are to communicate without others listening in, Bluetooth electronic equipment must be paired.
This means that the equipment must recognize one another and be accessed with the same number/pin code. The process is simple, only needs to be carried out once and safeguards against others with Bluetooth headsets being able to hear your phone conversations or receive your data on another pocket PC. For extra security, Bluetooth electronic equipment can hop randomly between 79 frequencies 1,600 times per second, which makes it virtually impossible for anyone to listen in. Furthermore, it is possible to encrypt the information sent between equipment units with a code that only those two units know.
It is also possible to ease security if, for instance, you wish to make it easier to exchange data or play against others with Bluetooth equipment (see Layton, Julia and Franklin, Curt. How Bluetooth Works). Bluetooth wireless technology works in an open frequency spectrum at 2. 4 gigahertz, the same as wireless networks, telephones and other electronic equipment. It is possible for all types of equipment to operate within the same spectrum without disrupting each other because a frequency consists of several channels which the equipment can hop between and, in that way, find channels which are quiet.
With the Bluetooth 1. 2 standard, electronic equipment can find quiet channels beforehand, communicate between them and resend data if anything is lost due to noise. Todays Bluetooth signals have strength of max. 2. 5 milliwatts and a range of approx. 10 meters (Class 2-equipment). The weak signal means that there must not be too many or large physical obstacles between the Bluetooth devices that are communicating. A key advantage of the weak signal of Bluetooth equipment is that the electromagnetic radiation emitted by all electronic equipment is very weak. In fact, the strength is approx.
1/800 of that emitted by a mobile phone (see Layton, Julia and Franklin, Curt. How Bluetooth Works). Conclusion This was an overview of Bluetooth giving insight to the key features and potential challenges of the technology. The technology occupies the 2. 4 GHz ISM band sharing the bandwidth with potential competing standards. It defines a Personal Area Network (PAN) whereas others advocate a Wide Area Network (WAN) approach. It is best positioned as a short-range wireless standard designed with the same cost goals and similar or greater reliability and performance as the cable it replaces.
Based on a frequency agile FHSS scheme it leverages hopping to avoid interference and it was not intended as a replacement for wireless LAN in a WAN scenario, because as yet it does not fully specify a hand over mechanism. References: 1. Bluetooth.
New Standard Encyclopedia, pp. 36-38. 2. Bluetooth. Grolier Encyclopedia of Knowledge, pp. 87-94. 3. J. Bray and C. F. Sturman, Bluetooth: Connect Without Cables, Prentice Hall. 4. Bluetooth. http://www. bluetooth. com/bluetooth/ 5. Bluetooth. Wikipedia, the free encyclopaedia, Feb.12, 2007. http://en. wikipedia. org/wiki/Bluetooth 6.
Bluetooth Information. http://www. filesaveas. com/bluetooth. html 7. Bluetooth: Goodbye Infrared. http://www. cellular. co. za/bluetooth. htm 8. Layton, Julia and Franklin, Curt. How Bluetooth Works. http://electronics. howstuffworks. com/bluetooth2. htm 9. Bluetooth Technology: What are the Applications? . http://www. mobileinfo. com/Bluetooth/applic. htm 10. Bluetooth Security Review, Part I. http://www. securityfocus. com/infocus/1830