Question

what are the limitation of delta modulation? and why it is needed to overcome it?

Answer 1

Explanation:

The two sources of noise in delta modulation are "slope overload", when step size is too small to track the original waveform, and "granularity", when step size is too large. But a 1971 study shows that slope overload is less objectionable compared to granularity than one might expect based solely on SNR measures.