Your Questions About Bluetooth Technology

Thomas asks…

how bluetooth technology function and what is its technical details?

i hv to delliver seminar on bluetooth functioning?

dknol answers:

Bluetooth wireless technology is a short-range communications technology intended to replace the cables connecting portable and/or fixed devices while maintaining high levels of security. The key features of Bluetooth technology are robustness, low power, and low cost. The Bluetooth specification defines a uniform structure for a wide range of devices to connect and communicate with each other.

Helen asks…

what are the advantages of bluetooth technology?

what are the advantages of blue-tooth technology?

dknol answers:

Bluetooth is a wireless technology that lets you connect wirelessly with other bluetooth enabled devices. You can transfer files between two bluetooth enabled devices(such as mobile phones) easily without having to worry about cables or a computer. Bluetooth enabled printers lets you print without having to connect anything physically.
Although the speed available over bluetooth connection is limited and slower than wired connections but its the wireless advantage that makes it a better choice for some cases.
Hope this helps.

James asks…

Contributions of ibm in the development of bluetooth technology?

dknol answers:

None, the technology was developed and created by erricsons in 1994.

Betty asks…

What is Bluetooth technology and how does it work?

dknol answers:


Bluetooth technology is a global standard that eliminates wires and cables between both stationary and mobile devices. It also facilitates both data and voice communication and offers the possibility of ad hoc networks and delivers the ultimate synchronicity between all personal devices.

The idea that resulted in the Bluetooth wireless technology was born in 1994 when Ericsson Mobile Communications decided to investigate the feasibility of a low-power, low-cost radio interface between mobile phones and their accessories. The Bluetooth wireless technology comprises hardware, software and interoperability requirements. It has been adopted not only by all major players in the telecom, computer and home entertainment industry, but also in such diverse areas as the automotive industry and healthcare, automation and toys, etc. – almost all sectors of the economy.

The technology

The Bluetooth Specification defines a short (around 10 m) or optionally a medium range (around 100 m) radio link capable of voice or data transmission to a maximum capacity of 720 kbps per channel. The Bluetooth technology supports both point-to-point and point-to-multipoint connections.

Radio frequency operation is in the unlicensed industrial, scientific and medical (ISM) band at 2.4 to 2.48 GHz, using a spread spectrum, frequency hoping, full-duplex signal at up to 1600 hops/sec. The signal hops among 79 frequencies at 1 MHz intervals to give a high degree of interference immunity. RF output is specified as 0 dBm (1 mW) in the 10m-range version and -30 to +20 dBm (100 mW) in the longer-range version.

When producing the radio specification, high emphasis was put on making a design enabling single-chip implementation in CMOS circuits, thereby reducing cost, power consumption and the chipsize required for implementation in mobile devices.

Voice: Up to three simultaneous synchronous voice channels are used, or a channel which simultaneously supports asynchronous data and synchronous voice. Each voice channel supports a 64 kbps synchronous (voice) channel in each direction.

Data: The asynchronous data channel can support maximal 723.2 kbps asymmetric (and still up to 57.6 kbps in the return direction), or 433.9 kbps symmetric.

* a Master can share an asynchronous channel with up to 7 simultaneously active Slaves in a Piconet.

* by swapping active and parked slaves out respectively in the piconet, 255 slaves can be virtually connected using the PM_ADDR and to park even more slaves the BD_ADDR can be used.
Slaves can participate in different piconets and a master of one piconet can be the slave in another, this is known as a Scatternet. Up to 10 piconets within range can form a Scatternet, with a minimum of collisions.

Bluetooth architecture overview

This section describes the Bluetooth architecture. The complete protocol stack comprises, as seen in Figure 1, of both Bluetooth specific (non-shaded) protocols and non-Bluetooth specific (shaded) protocols.

Different applications may run over different protocol stacks. Nevertheless, each one of these different protocol stacks uses a common Bluetooth data link and physical layer. The main principle in designing the protocols and the whole protocol stack has been to maximize the re-use of existing protocols for different purposes.

Bluetooth core protocols

The Baseband and Link Control layer enable the physical RF link between Bluetooth units forming a piconet. This layer controls the Bluetooth unit’s synchronization and transmission frequency hopping sequence. The two different link types defined in Bluetooth, Synchronous Connection Oriented, SCO, and Asynchronous Connectionless, ACL, are also managed by this layer.

Audio transmissions can be performed between one or more Bluetooth units, using different usage models. Audio data do not go through the L2CAP layer but go directly between two Bluetooth units.

The Host Controller Interface (HCI) provides a uniform interface method for accessing the Bluetooth hardware capabilities. It contains a command interface to the Baseband controller and link manager and access to hardware status. Finally, it contains control and event registers.

The Link Manager Protocol (LMP) is responsible for link set-up between Bluetooth units. It handles the control and negotiation of packet sizes. The LMP also handles management of power modes, state of a Bluetooth unit in a piconet and control of link and encryption keys for authentication and encryption.

The Bluetooth Logical Link Control and Adaptation Protocol (L2CAP) provides connection-oriented and connectionless data services to upper layers with protocol multiplexing capability, segmentation and reassembly operation, and group abstractions.

The Service Discovery Protocol (SDP) defines how a Bluetooth client’s application shall act to discover available Bluetooth servers’ services and their characteristics such as searching for a service, discovery of new services and detection of a no longer available service.

Cable replacement protocol

The RFCOMM protocol is a serial port emulation protocol. The protocol covers applications that make use of the serial ports of the unit. RFCOMM emulates RS-232 control and data signals over the Bluetooth baseband and provides transport capabilities for upper services (e.g. OBEX).

Telephony control protocol

The Telephony Control protocol – Binary (TCS Binary or TCS BIN) is a bit-oriented protocol, which defines the call control signaling for the establishment of speech and data calls between Bluetooth devices. In addition, it defines mobility management procedures for handling groups of Bluetooth TCS devices.

Besides TCS, a number of Telephony Control AT-commands are supported for transmitting control signals for telephony control. These use the serial port emulation, RFCOMM, for transmission.

Adopted protocols

The IETF Point-to-Point protocol (PPP) in the Bluetooth technology is designed to run over RFCOMM to accomplish point-to-point connections.

The TCP/UDP/IP standards are defined to operate in Bluetooth units allowing them to communicate with other units connected, for instance, to the Internet. Hence, the Bluetooth unit can act as a bridge to the Internet. The TCP/IP/PPP protocol configuration is used for all Internet Bridge usage scenarios in Bluetooth 1.0 and for OBEX (Object Exchange Protocol) in future versions. The UDP/IP/PPP configuration is available as transport for WAP (Wireless Application Protocol).

IrOBEX, shortly OBEX, is an optional application layer protocol designed to enable units supporting infrared communication to exchange a wide variety of data and commands in a resource-sensitive standardized fashion. OBEX uses a client-server model and is independent of the transport mechanism and transport API.

The Wireless Application Protocol (WAP) is a wireless protocol specification that works across a variety of wide-area wireless network technologies bringing the Internet to mobile devices. Bluetooth can be used like other wireless networks with regard to WAP; it can be used to provide a bearer for transporting data between the WAP Client and its adjacent WAP Server.

John asks…

Does the Dell Dimension 2400 series have a built in Bluetooth technology?

dknol answers:

No, you must either buy an after market bluetooth kit or pay extra for Dell to install an internal bluetooth module. 99% of Desktop PCs of that age have no use for bluetooth so manufacturers didn't add it.

Powered by Yahoo! Answers

This entry was posted in Default. Bookmark the permalink.