Delta Modulation using Simulink

Delta Modulation:

1. Next form of pulse modulation.
2. Transmits information only to indicate whether the analog signal that is being encoded goes up or goes down.
3. The Encoder Outputs are highs or lows that “instruct” whether to go up or down, respectively.
4. DM takes advantage of the fact that voice signals do not change abruptly.
5. The analog signal is quantized by a one-bit ADC (a comparator implemented as a comparator). 
6. The comparator output is converted back to an analog signal with a 1-bit DAC, and subtracted from the input after passing through an integrator.
7. The shape of the analog signal is transmitted as follows: a "1" indicates that a positive excursion has occurred since the last sample, and a "0" indicates that a negative excursion has occurred since the last sample.

Generation of Delta modulated signal using Simulink in MATLAB