The inventor of Bluetooth technology is Swedish telecom giant Ericsson. Because this technology has a very broad application prospect,1In May 1998, five top communication/computer companies in the world, Ericsson, Nokia, Toshiba, IBM and Intel, jointly established the Bluetooth Interest Group (Bluetooth SIG) through negotiation to accelerate its development, promotion and application. After the publication of this wireless communication technology, it quickly won the unanimous support of a large number of companies including Motorola, 3Com, Lucent, Compaq and Siemens. Up to now, more than 2,000 companies have joined Bluetooth SIG, including many of the world's most famous enterprises in the fields of computers, communications and consumer electronics, and even manufacturers and producers of automobiles and cameras. An open technical specification can get such extensive attention and support from the industry, which shows that products based on this Bluetooth technology will have broad application prospects and huge potential market. Bluetooth * * * The same interest group is now renamed Bluetooth Promotion Group.
Second, let me tell you an extra knowledge. Bluetooth is the name of the Scandinavian king who unified Denmark and Sweden in the Middle Ages. The king is famous for his novelty, which coincides with the new look of Bluetooth products. This is the origin of Bluetooth naming.
Bluetooth technical parameters
Working band ISM band, 2.402～2.480 GHz
Duplex mode full duplex, TDD time division duplex
The service type supports circuit-switched and packet-switched services.
Data rate 1Mb/ sec
The asynchronous channel rate of asymmetric connection is 72 1/57.6kb/s, and that of symmetric connection is 432.6 kb/s.
Synchronous channel rate 64Kb/s
The power required by the FCC in the United States is less than 0 DBM (1 MW), and other countries can extend it to 100mW.
The frequency of frequency hopping is 79 frequency points /MHz.
Frequency hopping rate 1600 times/second
Working Mode Stay/Hold/Sniff
The data connection mode is oriented to the connection service SCO, and there is no connection service ACL.
Error correction mode 1/3FEC, 2/3FEC, ARQ.
The authentication adopts reactive logic algorithm.
Channel encryption uses 0-bit, 40-bit and 60-bit keys.
Continuous variable slope modulation CVSD in speech coding mode
Generally, the transmitting distance can reach 10~ 10cm, and it can reach 100m with the increase of power.
Third, a group of experts such as the World Health Organization and IEEE said that the radiation of Bluetooth products has no effect on human body. The output power of Bluetooth products is only 1 MW, which is one millionth of that of microwave ovens and one thousandth of that of mobile phones. And only a small part of these outputs are absorbed by the human body. (Note: Do you know the concept of 1 MW? The power of an ordinary light bulb is 60 watts, and the power of a TV set is as high as 300 watts. Now the computer you use to browse my information has to be 300 watts. The emission power of the most "environmentally friendly" PHS has reached 400 MW per square meter, which should be quite safe. Even if the Bluetooth manufacturer adjusts the power to the maximum, it is only 100 MW, and the power of Bluetooth headset is only a quarter of that of PHS.
The radiation won't be very big!