Question

State any two advantages of FM modulation over AM modulation.

Answer 1

Frequency Modulation is the encoding of data during a carrier by varying the frequency of the carrier at that instant like the variation of the bottom waveform to be transmitted. Frequency Modulation is the encoding of data during a carrier by varying the frequency of the carrier at that instant like the variation of the bottom waveform to be transmitted.

Complete step by step answer: FM is angle modulation scheme, it was inspired by phase modulation but has proved to be more useful partly for its ease of generation and decoding.
Frequency Modulation is the encoding of data during a carrier by varying the frequency of the carrier at that instant like the variation of the bottom waveform to be transmitted.
Amplitude Modulation is a transmission systems technique wherein the baseband signal is superimposed with the amplitude of the carrier i.e the amplitude of the carrier is varying with proportion to the base waveform being transmitted.
Advantages of Frequency modulation over amplitude modulation:
The amplitude of a Frequency modulation wave remains constant over time. This allows the encoders and decoders the liberty to get rid of the noise from the received signal. This is through with the help of a filter that removes signals of wavelength greater than that of the transmitted signal thereby removing the noise. FM systems are noise immune systems. Since the AM signal transferred information using the amplitude, the envelope of the waveform can't be altered.
In AM systems, the facility consumption for signal transmission is higher in comparison to FM systems. In AM systems, the facility depends on the modulation index also called ‘MA’. When MA reaches unity, the facility consumption is 100%. In FM systems, the facility of the transmitted signal is proportional to the amplitude of the unmodulated carrier signal and it's constant. Therefore, FM is typically more power-efficient than AM systems.
In FM systems, the frequency deviation of the signal is said to the noise ratio. A higher frequency deviation means the baseband signals are often easily retrieved from the FM signals, whereas less deviation means it's harder to separate the info from the noise. In AM systems, the sole method of reducing noise within the transmission is to increase the transmitted power of the signal. This increases the cost of operation of the AM system.
In an AM system, there's no guard band in between two adjacent channels. This seriously increases the occurrence of interference of AM stations unless one signal is robust enough to overpower the opposite. Whereas within the case of FM signals, the adjacent FM channels are separated by guard bands which end up in little or no interference between adjacent FM channels.

Note: In an AM system, there's no guard band in between two adjacent channels.