In summary, Bluetooth® allows the user to replace traditional serial cables in order to send data, audio, or voice wirelessly. It is designed to operate a short range, typically 10 m, though in some cases the range can even be as great as up to 100 m. Bluetooth technology resides on the 2.4 GHz unlicensed ISM band. In order to operate without interference, Bluetooth utilizes a method called frequency hopping spread spectrum in which the signal will hop between a range of seventy nine frequencies between 2.401 to 2.480 GHz, 1 MHz each, in order to avoid colliding with other signals. The basic structure of a Bluetooth network topology is the piconet, a network of one master device and up to seven slaves. The master controls the group and determines what hopping sequence and timing to use. The master communicates with the devices one at a time, and a slave can transfer roles and become a master at any time. A user must become a member of the Bluetooth SIG, and follow the device qualification testing, in order to label a device as a Bluetooth product. There are two Bluetooth®-related technologies that are coming into play and enabling applications geared towards low power sensors; Bluetooth Low Energy (or BLE), and ANT technology. These allow the user to have Bluetooth connectivity in devices that are powered simply from a coin cell or receive power from energy harvesting.