| 摘要 |
PURPOSE:To improve S/N and to efficiently perform information transmission without imparing the quality of an original signal even when digital code information is added by compressing the component of the original signal by utilizing the correlation of the original signal in which time correlation is intensified in an analog area. CONSTITUTION:The transmission of a pseudo random signal generated from a pseudo noise generator 2 is controlled at a modulator 3 based on the digital code information 1 at a transmission side, and the output of the modulator 3 is converted to an analog signal with a D/A converter 5, and is added on an audio signal or a video signal with an analog adder 7, then, is changed to a transmission signal. A predictive filter 9 for the transmission signal is provided on a reception side, and a prediction error signal can be obtained by performing subtraction between a reception signal and the output of the prediction filter 9, and furthermore, it is decided whether or not a pseudo noise is included in the predictive error signal with a pseudo noise generator 10 which generates the same pseudo random signal as the pseudo random signal at the transmission side and a correlation detector 11. In such a manner, the digital code information can be obtained without impairing the dignity of the audio signal or the video signal. |
