| S. No |
Parameter |
PCM |
DM |
ADM |
DPCM |
| 1 |
Number of bits per sample. |
N can be 4,8,16,32, 64 etc. |
N = 1 |
N = 1 |
N is more than 1 but less than PCM. |
| 2 |
Step size. |
Depends on the number of Q levels. |
Step size is fixed. |
Step size is variable. |
Step size is fixed. |
| 3 |
Distortions/errors. |
Quantization error. |
Slope overload distortion and granular noise. |
Granular noise. |
Slope overload distortion and granular noise. |
| 4 |
Signaling rate and bandwidth. |
High |
Low, if the input is slow varying. |
Low |
Lower than PCM. |
| 5 |
System complexity |
Complex |
Simple |
Simple |
Simple |
| 6 |
Feedback from output. |
No feedback |
Feedback is present. |
Feedback is present. |
Feedback is present. |
| 7 |
Noise Immunity |
Very good |
Very good |
Very good |
Very good |
| 8 |
Use of repeater |
Possible |
Possible |
Possible |
Possible |
| 9 |
Area of applications |
Audio and video Telephony |
Speech and images |
Speech and images |
Speech and videos. |
