Patent ID: 7272375

Claim:
A portable device having an integrated terrestrial audio broadcast receiver, comprising: a channel selection interface; an audio output interface; and an integrated terrestrial audio FM receiver coupled to the channel selection interface and the audio output interface, the audio receiver comprising: a mixer coupled to receive a signal spectrum and a mixing signal as inputs and having a low-IF signal as an output, the signal spectrum comprising an FM audio broadcast signal spectrum comprising a plurality of FM channels from terrestrial audio FM broadcasts, the mixer being configured to output real and imaginary low-IF signals; local oscillator (LO) generation circuitry coupled to receive an FM channel selection signal as an input and configured to provide an oscillation signal, the oscillation signal being dependent upon the FM channel selection signal and being used to generate the mixing signal for the mixer; quadrature generation circuitry configured to receive the mixing signal from the LO generation circuitry and to generate two phase shifted mixing signals for use by the mixer; low-IF conversion circuitry coupled to receive the low-IF signals from the mixer and configured to output digital signals, the low-IF conversion circuitry including first and second analog-to-digital converters coupled to the real and imaginary low-IF signals and configured to output real and imaginary digital signals; a digital-signal-processor (DSP) coupled to receive the digital signal from the low-IF conversion circuitry and configured to demodulate the frequency modulation within the selected FM channel, to decode the FM stereo encoding within the selected FM channel, to digitally tune the selected FM channel, and to output a digital audio signal, the DSP comprising an on-chip microcontroller; and digital-to-analog converter (DAC) circuitry coupled to receive the digital audio signal from the DSP and configured to output an analog audio signal; wherein the mixer, the LO generation circuitry, the low-IF conversion circuitry, and the DSP including the microcontroller are integrated within a single integrated circuit; and wherein the integrated circuit is made using a CMOS process.