Inside Bluetooth ULP technology

Bluetooth Version 2.1 + EDR and Version 3.0 + HS (commonly referred to as "Classic Bluetooth technology") and Bluetooth low-energy technology have much in common: they are all low cost, short range, interoperable, robust wireless technologies operating in the license-free 2.4GHz Industrial, Scientific and Medical (ISM) RF band.

But there is one critical difference: Bluetooth low-energy technology was designed from the outset to be an "ultra-low power" (ULP) wireless technology whereas Classic Bluetooth technology forms a "low power" wireless connection.

Classic Bluetooth technology is a "connection oriented" radio with a fixed connection interval ideal for high activity connections like mobile phones linking with wireless headsets. In contrast, Bluetooth low-energy technology employs a variable connection interval that can be set from a few milliseconds to several seconds depending on the application. In addition, because it features a very rapid connection, Bluetooth low-energy technology can normally be in a "not connected" state (saving power) where the two ends of a link are aware of each other, but only link up when absolutely necessary and then for as short a time as possible.

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