What are the properties of angle modulation?

The properties of angle modulation, including frequency modulation (FM) and phase modulation (PM), depend on several factors, including the amplitude and frequency characteristics of the modulating signal and the carrier signal. Here are some general properties of angle modulation:

1. Constant amplitude: In angle modulation, the amplitude of the carrier signal remains constant. Only the phase or frequency of the carrier signal is modified to carry information.

2. Bandwidth: Angle modulation has a wider bandwidth than amplitude modulation (AM), which means that it can transmit more information per unit of time.

3. Resistance to noise: Angle modulation is more resistant to noise than AM, which makes it suitable for high-fidelity audio transmission and other applications where signal quality is important.

4. Modulation index: The extent to which the carrier signal is modulated depends on the modulation index, which is the ratio of the amplitude of the modulating signal to the frequency deviation of the carrier signal in FM, or to the phase deviation of the carrier signal in PM. A higher modulation index results in a more highly modulated carrier signal.

5. Non-linear distortion: In FM, non-linear distortion can occur if the amplitude of the modulating signal is too high. This can result in signal distortion and interference with neighboring channels. In PM, non-linear distortion can occur if the amplitude of the modulating signal is too high or if the phase deviation is too large.