Apparatus and method for frequency modulation transmitting of audio signal

An apparatus and a method for the FM(Frequency Modulation) transmission of audio signals are provided to offer clearer audio signals to users by using an FM transmission function in order to output audio signals, which are generated as a call or an arbitrary mode using a Bluetooth handsfree function is executed in a noisy vehicle environment, to a vehicle speaker. If a call connection request is made while a navigation terminal is executing an arbitrary mode(S301), the navigation terminal transfers to a handsfree mode(S303). In the handsfree mode, the navigation terminal transmits and receives audio signals with a portable terminal through short range wireless communication(S305). In this case, the navigation terminal outputs audio signals, transmitted from the portable terminal, through its own speaker. If an FM transmission request for audio signals is generated(S307), the navigation terminal turns on an FM transmitter(S313) and sets an FM frequency(S315). The navigation terminal performs path changeover to transmit audio signals to a vehicle audio system(S317). The navigation terminal outputs audio signals, delivered through short range wireless communication from the portable terminal, to the vehicle audio system(S319).