Patent attributes
A FM output portable audio player is provided for digitally coupling audio signals generated therein to be broadcast through a radio receiver system, such as an automobile radio. The audio player includes an audio signal source for generating digital audio output signals. Digital audio interface circuitry is coupled directly to the digital audio output signals and includes a digital FM stereo/RDS multiplexer for modulating the digital audio output signals on a RF carrier to produce a modulated audio signal. An internal antenna is coupled to the digital FM stereo/RDS multiplexer. The portable audio player is capable of wirelessly transmitting the modulated signal to the radio receiver system. The digital audio interface circuitry is formed of integrated circuit chips which provides for lower cost, a compact size, and a higher audio quality. A radio data signal is also multiplexed by the digital FM stereo/RDS multiplexer to generate the modulated signal having the radio data signal centered about a 57 kHz suppressed carrier.
