Importance

Loading Importance Indicators...

Abstract

A method and apparatus for adjusting the power level and spectral content of a digital signal which is transmitted at the same frequency as an audio signal which is modulated via analog modulation method so that the receiver receiving the audio signal is not perceptibly impaired and the power of the digital signal is maximized. The transmission and reception system comprises at least two transmitters for transmitting first and second signals. The first transmitter transmits an audio signal via an analog modulation technique and the second transmitter transmits digital information. A first and second receiver for receiving the two different signals, a power adjustment controller, and processor for adjusting the power of the second digital signal in relation to the first audio frequency range signal at the transmitters. The transmission system transmits the first and second signals to both receivers within a single channel. To allow the power level of the second transmitter to be maximized, the present invention takes advantage of the psychoacoustic effects properties of auditory perception. The power adjustment controller manipulates the second transmitted signal so that the noise induced into the first receiver is below the global masking threshold of the audio signal modulating the first transmitter. Thus, the noise induced by the second transmitted signal cannot be perceived by the human ear and is effectively eliminated.

Loading the Abstract Image...

First Claim