DPCM MODULATOR AND DEMODULATOR

摘要

PURPOSE:To generate overload noises by converting a PCM signal into a DPCM signal having the same number of bits and transmitting the signal while compressing the data by means of digital compression to decrease the number of transmission bets. CONSTITUTION:An analog signal is converted into the DPCM signal at a part surrounded by broken lines in the figure. This DPCM signal has at worst the number of bits equal to that of the PCM signal being an output of an A/D converter 3. The number of transmission bits is decreased without generating overload noises by transmitting this DPCM signal while being compressed by digital compression circuit 15.