handfree profile (Bluetooth) (HFP)

There are several standardized Bluetoothprofiles for short-range wireless communication, such as the Handfree Profile (HFP) and the SIM Access Profile( SAP). Both Bluetooth profiles are used in automotive technology and support the carkit.

Handfree is the hands-free feature that allows the cell phone to be voice-controlled and thus accept or make calls. The sampling frequency for mono transmission is 3.1 kHz. In addition to handsfree, the Handfree profile handles call control of incoming and outgoing calls, connection management, and transferring numbers from the handsfree to the cell phone.

In this Bluetooth profile, the cell phone acts as the audiogateway( AG) and the switching component in the motor vehicle is the hands-free gateway( HG). The HG gateway enables the vehicle's own loudspeakers and microphone.