What is Bluetooth?什么是蓝牙

Bluetooth is a universal radio interface in the 2.45GHz frequency band that enables portable electronic devices to connect and communicate wirelessly via short-range, ad hoc networks. Each unit can simultaneously communicate with up to sever other units per piconet. Moreover, each unit can simultaneously belong to several piconets.

　　What is Bluetooth Technology？

　　Bluetooth technology which apart from Ericsson, has gained the support of Nokia, IBM, Toshiba, Intel and many other manufacturers

　　eliminates the need for wires, cables and connectors for and between cordless or mobile phones, modems, headsets,PDAs, Computers, printers, projectors, local area networks, and so on, and paves the way for new and completely different devices and applications.Technology Characteristics

　　1Ms/s symbol rate exploits maximum available channel bandwidth

　　Fast frequency hopping avoids interference

　　Adaptive output power minimizes interference

　　Short data packets maximize capacity during interference

　　Fast acknowledge allows low coding overhead for links

　　CVSD （Continuous Variable Slope Delta Modulation） voice coding enables

　　operation at high bit- error rates

　　Flexible packet types supports wide application range

　　Air interface tailored to minimize current consumption

　　Basic Technical Information—Based upon a small , high performance integrated radio transceiver ,each of which is allocated a unique 48-bit address derived from the IEEE 802·standard .

　　Operate in the unrestricted 2.45GHz ISM free band, Which is available globally although slight variation of location and width of band apply

　　Range set at 10m to optimize for target market of mobile and business user

　　Gross data rate 1Mbit/s with second generation plans to increase to 1Mbit/s

　　One-to-one connections allow maximum data transfer rate of 721kbit/s （3 voice channels）

　　Uses packet switching protocol based on frequency hop scheme with 1600 hops/s to enable high performance in noisy radio environments .The entire available frequency spectrum is used with 79 hops of 1Mhz bandwidth , analogous to the IEEE 802.11 standard

　　Low power consumption longevity for battery powered devices . During data transfer the maximum current drain is 30mA. However during pauses or at lower data rates will be lower