| 摘要 |
The privacy signal transmission system comprises a transmitter (100) including digital pulse modulator (1) for converting a first analog signal (Xin) into a first digital signal (X1). An encryption means (2) converts the first digital signal into a digital privacy signal, and an extractor extracts a first error signal representative of a difference between a second analog signal provided by analog conversion of the first digital signal and the first analog signal. The first error signal and the first digital privacy signal are transmitted by a transmission means (25, 7) to a receiver (101) including means for receiving the first error signal and the first digital privacy signal to individually generate a second error signal and a second digital privacy signal. A decryption means (15) converts the second digital privacy signal into a second digital signal which is converted by a digital pulse demodulator (16) into a third analog signal (X16). The first analog signal is reproduced in a reproduction means (20, 21) by adding the error signal (X19) to the third analog signal (X16).
<??>This system is capable of transmitting quality analog signals despite the use of an inexpensive digital encryption circuit. |
