What is Bluetooth
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BLUETOOTH

Wireless connected!

Bluetooth is an IEEE802.15.1 industry standard to transfer data wireless between identical or different devices. The transfer rate ranges from 723.2 kbit/s (v.1.2) up to 24 Mbit/s (V 3.0 + HS).

Diff erent Bluetooth versions in comparison

Bluetooth 1.0 Was fl awed by security issued due to Bluetooth Hardware Device Address Transmission (BD_ADDR), supports data transfer rates up to 732.2 kbit/s
Bluetooth 1.1 Achieves data rates of 732.2 kbit/s
Bluetooth 1.2 Same as 1.1 (732.2 kbit/s) but more stable and reliable data compared to 1.1 kbit/s
Bluetooth 2.0 + EDR Supports EDR (Enhanced Data Rate) providing up to 2.1 Mbit/s
Bluetooth 2.1 + EDR Same as 2.0 with improved coupling capabilities to connect devices more easily.
Bluetooth 3.0 + HS Supports data rates of up to 24 Mbit/s by utilizing a Highspeed (HS) data channel based on WiFi and UWB (Ultra Wide Band)
Bluetooth 4.0 Designed for power saving, not fully backward compatible with data rates of up to 732.2 kbit/s

The most important Bluetooth profi les and their features

Bluetooth profi les play a central role. They defi ne the protocol and content of a conversation in relation to the used application. Bluetooth profi les enable bluetooth devices of different manufacturers to work together at the application level. A good example is the communication between cell phone and headset. Both devices do not need to be built by the same manufacturer.
Each profi le defi nes rules and protocols providing the advantage for the user of not having to manually tune devices to connect to each other. Beside having this feature, Bluetooth supports more than one profi le at the same time. A profi le keeps the supported features of a device to a minimum needed by the application, helping maintain a small energy footprint and small layout. Therefore a device only needs a small feature set but not the full library of Bluetooth features.

Name Profil Application
GAP Generic Access Profile basic protocol for authentication and connection
A2DP Advanced Audio Distribution Profile wireless stereo connection for headphones and sound systems
SCO Synchronous Connection-Oriented Link Access to microphone and headphones of a headset
PBAP Phonebook Access Profile Access to telephone inventory / phone book (read only)
DUNP Dial-Up Networking Profile Connect via GSM, UMTS, analog modem or ISDN to a network like the internet
HFP Hands Free Profile manufacturer independent connection between smartphone and hands-free phone system
BIP Basic Imaging Picture transfer
BPP Basic Printing Profile Printing via parallel interface
SAP SIM Access Profile SIM card access
GAVDP Generic AV Distribution Audio and video transfer
AVRCP Audio / Video remote Audio/Video-Fernbedienung
Beside these profi les there are several more, which are not listed here.