What ist Bluetooth?

Wireless data transfer

Bluetooth allows data to be transmitted wirelessly between devices such as Bluetooth headphones and a smartphone.

Bluetooth is an industry standard developed in the 1990s in accordance with IEEE 802.15.1. Incidentally, it was named after the Danish King Harald Bluetooth. The Bluetooth symbol is made up of the runes ᚼ (h) and ᛒ (b), which were the initials of Harald Bluetooth.

The data transfer rate ranges from 732.2 Kbit/s (V 1.2) to 50 Mbit/s with Bluetooth 5.X. The latest version is Bluetooth 6, which was released in September 2024 with new features and functions. Devices with the latest standard are expected in 2025.

Bluetooth versions at a glance

Bluetooth 1.0	Enthielt Sicherheitsprobleme durch Bluetooth Hardware Device Address Transmission (BD_ADDR), maximale Datenübertragungsrate von 732,2 Kbit/s
Bluetooth 1.1	Ermöglicht eine Datenübertragungsrate von 732,2 Kbit/s
Bluetooth 1.2	Ermöglicht eine stabilere Datenübertragung als Version 1.1 und eine Datenübertragungsrate von 732,2 Kbit/s
Bluetooth 2.0 + EDR	Ermöglicht mit der EDR (Enhanced Data Rate) eine maximale Datenübertragungsrate von 2,1 Mbit/s
Bluetooth 2.1 + EDR	Datenübertragungsrate wie die Version 2.0, besitzt jedoch verbesserte Technik zur Verbindung von Bluetooth-fähigen Geräten
Bluetooth 3.0 + HS	Ermöglicht eine Datenübertragungsrate von maximal 24 Mbit/s (bei Nutzung eines zusätzlichen Highspeed (HS) Kanals auf Basis von WLAN und UWB (Ultra Wide Band))
Bluetooth 4.0	Sehr stromsparend, nicht vollständig abwärtskompatibel, ermöglicht Datenübertragungsraten bis zu 732,2 Kbit/s
Bluetooth 5	Reichweite wurde vervierfacht, maximale Datenübertragungsrate von 2 Mbit/s, es können bis zu acht Geräte gleichzeitig verbunden werden. Vollständig abwärtskompatibel zu Bluetooth 4.0
Bluetooth 5.1	Verbesserte Ortung mit Direction Finding ermöglicht eine präzisere Positionsbestimmung durch Winkelmessung.
Bluetooth 5.2	Führte Enhanced Attribute Protocol (EATT) für effizienteres Multi-Device-Handling ein und brachte Verbesserungen bei der Audioqualität mit LE Audio.
Bluetooth 5.3	Reduzierte den Energieverbrauch durch bessere Steuerung der Übertragungseinstellungen und verbesserte die Robustheit in überfüllten Frequenzbereichen.
Bluetooth 5.4	Optimierte die IoT-Kompatibilität durch Unterstützung für größere Netzwerke und bessere Sicherheitsfeatures für industrielle Anwendungen.
Bluetooth 6	Bluetooth 6 wird voraussichtlich energieeffizienter, schneller und präziser in der Ortung sein.

Bluetooth 4.0: Connect accessories in an energy-saving way

Bluetooth 4.0 has been available since around 2011, but has only been usable on Android-based devices since 2013. Compared to the previous versions, version 4.0 consumes significantly less energy. With Bluetooth 4.0, the connection between devices, such as a Bluetooth keyboard or a Bluetooth headset, is also established more quickly and is maintained over a distance of up to 100 metres. One disadvantage is the lack of downward compatibility of the new protocols. Although Bluetooth 4.0, like all previous standards, operates on the 2.4 GHz frequency, it uses 40 radio channels of 2 MHz each. However, older Bluetooth accessories do not support this radio channel distribution.

Although the data rate of Bluetooth 4.0 is theoretically one Mbit/s, the standard is not suitable for transferring larger files. Bluetooth 4.0 is designed so that the devices only wake up briefly to transfer information quickly. The devices then switch back to a power-saving deep sleep. This information includes values such as pulse rate or blood sugar levels. The standard is therefore particularly suitable for Bluetooth accessories in the health, sports and smart home categories.

The Bluetooth devices must also support GATT (General Agreement on Tariffs and Trade), which is a Generic Attribute Profile. Up to Bluetooth standard 4.0, devices used GAP (Generic Access Profile). With versions 4.1 and 4.2, faster data transmission, more security and even greater energy savings were achieved.

Bluetooth 5: Use more range or higher data transmission

Unlike its predecessors, the Bluetooth standard is not called 5.0, but simply Bluetooth 5. The Bluetooth Special Interest Group (SIG) decided on this name change when it was introduced at the end of December 2016, heralding a completely new era in the wireless transmission of data.

SIG has quadrupled the range, doubled the speed of low-energy connections and simultaneously increased the capacity of connectionless data transmissions by a factor of eight. With Bluetooth 5, it is therefore possible to transfer data between two compatible devices at a distance of up to 240 metres. However, the further the distance, the lower the data transfer rate. While up to 500 Kbit/s can be transmitted at 120 metres, the rate is only 128 Kbit/s at 240 metres. You therefore benefit from either a higher speed or greater range. The range has an advantage when using Bluetooth headphones or loudspeakers in your home. The connection is not interrupted when you move to another room. Bluetooth 5 also allows you to connect up to eight devices simultaneously and is fully backwards compatible with Bluetooth 4.0.

In the following years, the Bluetooth standards were further improved with versions 5.1 to 5.4. Bluetooth 5.1 introduced Direction Finding, which enabled more precise positioning through angle measurement - an important advance for location services. Bluetooth 5.2 introduced LE Audio, which significantly improved audio quality and enabled more efficient handling of multiple devices thanks to the Enhanced Attribute Protocol (EATT). Bluetooth 5.3 optimised energy consumption through finer control of transmission settings and improved performance in crowded frequency ranges. Finally, Bluetooth 5.4 focused on IoT compatibility, increased capacity for larger networks and improved security features, especially for industrial applications.

Bluetooth 6

Bluetooth 6 wird voraussichtlich Verbesserungen in Energieeffizienz, höhere Datengeschwindigkeiten und eine noch präzisere Ortungsgenauigkeit bringen, ideal für IoT- und Smart-Home-Anwendungen. Zudem sind erweiterte Sicherheitsfeatures und Optimierungen für größere Netzwerke im Gespräch, um die Leistung und Zuverlässigkeit in industriellen und öffentlichen Umgebungen weiter zu steigern.

Bluetooth accessories: The most important profiles and their functions

The profiles in Bluetooth are of central importance. They define the structure and content of a specific communication depending on the application. The Bluetooth profiles allow Bluetooth accessories to work together at application level and therefore guarantee that Bluetooth devices from different manufacturers can work together. A typical example is communication between a mobile phone and a Bluetooth headset. Both devices do not have to come from the same manufacturer. Rules and protocols are defined in a profile. This gives the user the advantage of not having to manually synchronise the devices. In addition, Bluetooth allows several profiles at the same time. A profile limits the device to the functions required for the specific application, which keeps it small and energy-efficient. This means that the device only needs to have a small range of functions and does not need to be able to handle every conceivable function.

GAP	Generic Access Profile - Basic procedure for authentication and establishing a connection
A2DP	Advanced Audio Distribution Profile - Wireless stereo connection for speakers or Bluetooth headphones
SCO	Synchronous Connection-Oriented Link - access to both the microphone and the headphones of a Bluetooth headset
PBAP	Phonebook Access Profile - Access to phonebook (read only)
DUNP	Dial-Up Networking Profile - Dial-up via GSM, UMTS, analogue modem or ISDN into a network, for example for Internet access
HFP	Hands Free Profile - manufacturer-independent communication between mobile phone and hands-free system
BIP	Basic Imaging - Image transmission
BPP	Basic Printing Profile - Printing via the parallel interface
SAP	SIM Access Profile - SIM card access
GAVDP	Generic AV Distribution - Audio and video transmission
AVRCP	Audio Video Remote Control - Audio/video remote control

High-quality Bluetooth products for perfect sound

You can find the entire InLine Bluetooth range here

InLine® Bluetooth 5.3 audio receiver with 96 watt amplifier

Compact streaming hub with 96 W for passive speakers Flexible input: Bluetooth 5.3 or line-in via RCA for wireless and wired sources. Directly drive passive speakers: Up to 96 W output power for powerful stereo sound. Pair two devices in parallel: Qu...

Item no.: 99209L

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InLine® Bluetooth 5.1 HiFi Receiver & USB DAC, with LCD

Upgrade existing hi-fi system wirelessly and via USB Easy upgrade without a new purchase: Wireless streaming or USB DAC for existing audio devices. Flexible connection to the system: Either analog via RCA stereo or digital via Toslink. Quick operatio...

Item no.: 99209M

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InLine® Airplane Bluetooth Audio Transmitter, BT 5.0, aptX HD/LL

Wireless on-board entertainment for your headphones Flexible use on board: Compatible with one-, two-, and three-pole audio connections. Low-latency listening: Low latency provides more synchronized audio. Two headphones simultaneously: Share audio i...

Item no.: 99160I

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