# Angle Modulation

**Phase Modulation**

s(t) = A cos (Ï‰_{c}t + k_{p}m(t))

s(t) = phase modulated carrier wave.**Frequency Modulation**s(t) =

where, s(t) = frequency modulated carrier wave.Modulation index (m_{f}) =

Transmission Bandwidth of FM Signal:

# Sampling Theorem

A continuous time signal may be completely represented by its samples and recovered back from its samples under the condition that the sampling frequency is f_{s} â‰¥ 2f_{m}.

Here,

f_{s} = sampling frequency

f_{m} = maximum frequency component present in the signal.

When sampling rate become exactly equal to 2f_{m} per seconds, then it is called Nyquist rate and the maximum sampling interval is called Nyquist interval.

Î¼**-law companding : **Formula for Î¼-law companding is

**
A-law Companding : **A-law companding is given by the formula:

The major disadvantage of Delta modulation is

- Slope Overload distortion.
- Granular Noise distortion.