Piconets

Piconet is a Bluetooth-based personal area network consisting of a single master and up to seven active slave devices. The master coordinates all communication, provides the clock, and decides the frequency-hopping sequence used by the devices in the piconet. Slaves synchronize to the master's clock and hop along the same pseudo-random, frequency-hopping pattern across the 2.4 GHz ISM band.

Operation relies on time-division multiplexing: each 625 microsecond time slot is allocated to a device for transmission or reception. The network shares the band by hopping through channels, which helps mitigate interference from other wireless sources.

Bluetooth supports other states to manage larger collections of devices: additional devices can be kept in parked, sniff, or hold modes, but only seven can be active slaves in a piconet at once. A device can participate in more than one piconet to form a scatternet, though this increases complexity and potential timing conflicts.

Range varies with power class and environment. Typical class 2 devices offer about 10 meters of range, while class 1 devices can reach tens of meters; actual performance depends on obstacles and interference. Data rates in classic Bluetooth are modest, with higher rates available in newer revisions via Enhanced Data Rate.

Piconets are used to connect peripherals such as headphones, keyboards, and computers in a convenient short-range network. They are the foundational element of Bluetooth's topology and enable simple, ad-hoc wireless devices to exchange information.