Data during analog audio

摘要

This application discusses among other things, apparatus and method for transmitting data with an analog signal without significantly distorting the analog signal. In an example, an apparatus can include an audio channel, a capacitor coupled to a first conductor of the audio channel, the capacitor configured to couple an analog representation of a digital data signal with an analog audio signal on the audio channel, and a frequency modulator configured to receive the digital data signal and to modulate a frequency of an output signal of the frequency modulator based on a logic level of the digital data signal, wherein the analog representation of the digital data signal includes the frequency of the output signal of the frequency modulator.

主权项

1. An apparatus comprising:
an audio channel; a capacitor coupled to a first conductor of the audio channel, the capacitor configured to couple an analog representation of a digital data signal with an analog audio signal on the audio channel; a frequency modulator configured to receive the digital data signal and to modulate a frequency of an output signal of the frequency modulator based on a logic level of the digital data signal, wherein the analog representation of the digital data signal includes the frequency of the output signal of the frequency modulator and wherein the output signal of the frequency modulator includes a square waveform; and a transmitter amplifier configured to receive the square waveform and to provide a sinusoidal waveform.