Bluetooth Characteristics

Bluetooth enables users to connect a wide range of computing and telecommunication devices without any additional or proprietary cables. Bluetooth provides short-range, low-cost (_≤ $10 per device) connectivity between portable devices. Bluetooth is limited in range (_10 meters) and bandwidth (780 kbps compared to Home RF that goes to 1–2 Mbps and IEEE 802.11b that goes to 11 Mbps with 150 m and greater distance). Bluetooth radio characteristics [8–10] include low power, short range, and medium transmission speed. The low power consumption makes Bluetooth ideal for small, battery-powered devices like mobile phones and pocket PCs. Bluetooth is poised to capitalize on the emerging market of small mobile devices that is expected to grow. Bluetooth’s

These devices are being embraced by industries using mobile automation systems. For example, at a car rental facility, an employee could use a Bluetooth-enabled pocket PC equipped with a bar code scanner to scan a vehicle identification number, enter mileage and fuel data, then instantly transmit a receipt to a Bluetooth-enabled portable printer worn on the hip. Because of the GSM subscriber identity module (SIM), industry experts foresee Bluetooth-enabled GSM phones to be used like credit cards. For example, one could use the Bluetooth-enabled mobile phone at a Bluetooth-enabled vending machine to charge one’s account and buy a drink. One of Bluetooth’s greatest advantages is that it can be used absolutely anywhere that at least two Bluetooth devices share a 10-m range. It is possible because Bluetooth is designed for direct point-to-point networking between devices and does not require proximity to infrastructure stations like signal towers or access

They use the 2.4-GHz Industrial, Scientific and Medical (ISM) frequency band. They implement a frequency hopping spread spectrum (FHSS) scheme with binary frequency shift keying (BFSK) modulation. Devices that communicate using Bluetooth form what is termed a piconet. Piconets can connect up to eight different devices. Devices can be in more than one piconet. A group of piconets with connections between them is called a scatternet. Each piconet consists of a master and up to seven active slaves. The master unit characterizes the piconet channel by setting the hop sequence. The master unit initiates a connection to a slave unit. Any unit in a piconet can become a master, thus the naming of master-slave convention refers only to the protocol on the channel [16]. Power management features in Bluetooth exist at two levels. At a low level, when handling packets, and at a high level, using low power operation modes