| The networking standards of Bluetooth will | | | | devices will form a network. Bluetooth |
| transmit data via low power radio frequency. | | | | devices will create a PAN (Personal Area |
| Bluetooth communicates on a 2.45 GHz | | | | Network) or piconet that may fill a room. |
| frequency. This very band of frequency has | | | | Once the piconet has been established, the |
| been set aside by international agreement for | | | | devices will randomly hop in frequencies. |
| the use of industrial and medical devices. | | | | |
| | | | Bluetooth technology profiles will describe |
| Many devices that you already known and use | | | | how the technology is used. Profiles can be |
| take advantage of this frequency band. Garage | | | | best described as vertical slices through the |
| door openers, baby monitors, and the next | | | | protocol stack. It will define options in |
| generation of mobile phones all use this | | | | each protocol that are mandatory for the |
| frequency within the ISM band. Ensuring that | | | | profile. |
| Bluetooth and the other devices do not | | | | |
| interfere with each other is a crucial part | | | | The profile will also define the parameter |
| of the design process. | | | | ranges for each protocol. The concept of the |
| | | | profile is used to decrease the risk of |
| One of the ways Bluetooth will avoid | | | | interoperability problems between the |
| interfering with other electronic devices is | | | | different products. These profiles will not |
| by sending out weak signals of around 1 mw. | | | | normally define any additions to the |
| In comparison, even the most powerful of cell | | | | Bluetooth specification, which is why you can |
| phones can transmit a signal of 3 watts. | | | | add new profiles where you need them. The |
| | | | Bluetooth underlying technology is the same, |
| The low power signals will limit the range of | | | | only the specific method that it's used is |
| a Bluetooth device to around 32 feet, which | | | | defined. |
| cut the chances of interference between your | | | | |
| computer and other electronic devices. Even | | | | Generally speaking, all profiles of Bluetooth |
| though it has low power, Bluetooth does not | | | | are based on the GAP (Generic Access |
| require a line of sight between the | | | | Profile). There are many profiles that fall |
| communicating devices. The walls in your home | | | | in the GAP category.a) AVRCP, Audio/Video |
| will not stop the signal, making it great for | | | | Remote Control Profileb) ESDP, Extended |
| rooms throughout the house. | | | | Service Discovery Profilec) CIP, Common ISDN |
| | | | Access Profiled) PAN, Public Area Network |
| Bluetooth can connect 8 devices at the same | | | | Profilee) HCRP, Hardcopy Cable Replacement |
| time. With each of those devices on the same | | | | Profilef) GAVDP, Generic Audio/Visual |
| radius, you may think they would interfere | | | | Distribution Profileg) A2DP, Advanced Audio |
| with each other, although it is very | | | | Distribution Profileh) VDP, Video |
| unlikely. Bluetooth utilizes a technique | | | | Distribution Profilei) HID, Human Interface |
| known as low frequency hopping, which makes | | | | Device Profile |
| it harder for more than one device to | | | | |
| transmit on the same frequency at the same | | | | To put it another way, usage models will |
| time. | | | | describe Bluetooth device applications and |
| | | | the associated profiles that are used. The |
| With this technique, a device will use 79 | | | | usage model focuses mainly on three |
| individual, randomly chosen frequencies | | | | categories; voice/data access points, |
| within a designated range, which change from | | | | peripheral interconnects, and PAN (Personal |
| one anotheron a regular basis. | | | | Area Networking). |
| | | | |
| In the case of Bluetooth, the transmitters | | | | The voice and data access points involve |
| will change frequency 1,600 times or more | | | | connecting computing devices to communicating |
| every second, meaning that more devices can | | | | devices through a wireless link. This way, |
| make fulluse of the radio spectrum. Since | | | | data can be transferred in a wireless manor, |
| every transmitter of Bluetooth will use | | | | without the need of cables or other types of |
| spread spectrum automatically, it is very | | | | connectivity. |
| unlikely that twotransmitters will be on the | | | | |
| same frequency at the exact same time. | | | | PAN is another very important usage model |
| | | | with strong appeal to business customers. |
| When the Bluetooth devices come within close | | | | Bluetooth networks are easy to set up in |
| range of each other, an electronic | | | | virtually any type of environment. An example |
| conversation will occur to determine whether | | | | would be meeting others at a trade show. |
| or not they have data to share or whether one | | | | |
| needs to take total control. The user does | | | | Instead of having contact information beamed |
| not have any buttons to press or commands to | | | | via infrared, business cards can quickly and |
| give, as the conversation will occur | | | | easily be transferred via Bluetooth wireless. |
| automatically. | | | | The fact is that many documents can be |
| | | | exchanged this very same way, making the uses |
| Once the conversation has occured, the | | | | and possibilities virtually endless. |