Frequency Modulation (FM) Vs. Amplitude Modulation (Am) Essay Sample

Frequency and Amplitude Modulation has been in used for communication lines for many years (Poole, n.d.). During the early stages of wireless communication, frequency modulation (FM) cannot function under circumstances employing narrower bandwidth thus amplitude modulation (AM) is more predominant. Throughout the years of usage of FM and AM, the advantages and disadvantages between these two modulation types have been observed and have been used as basis for appropriate application.
The use of amplitude modulation over frequency modulation has its advantages and drawbacks. AM can be implemented easier, thus it is simpler compared to FM. It can be demodulated upon using a circuit with few and less specialized components making it cheaper to employ. However, AM signal is not efficient when it comes to power and bandwidth usage. AM signal requires a bandwidth which is twice the highest frequency of the audio. Additionally, AM is more prone to noise especially ones with high levels. The detectors of AM signal are sensitive to noise since noise is amplitude based. With AM being used less frequently, FM is being widely used because of its broad advantages. Frequency modulation is robust to noise and variations in signal strength. This type of modulation is used in the broadcasting industry. In FM usage, noise is removed by applying signal through a limiter so that variations in frequency can appear. The signal level, additionally, is an important factor to consider upon noise removal since it must be sufficiently high in order to limit the signal. The variation in signal strength can be removed in the same manner. Moreover, FM does not need linear amplifiers and it also has greater efficiency compared to other modes. With the advantages of FM presented, it also has its own drawbacks which can be overcome or may require usage of other formats of modulation. The usage of FM mode requires a complicated type of demodulator thus more expensive to purchase. Another disadvantage of FM is that some other modes may have higher efficiency of data spectral. Based on theories regarding FM and another possible disadvantage of it is that FM sidebands tend to extend to infinity in either side. To overcome this, a filter must be introduced which can cause distortion to the signal (Poole, n.d.).
Despite existence of digital transmissions, FM usage is still important. It is applied in variety of radio communication and two way radio communications. The very high quality transmission medium quality of FM is important in high quality broadcasting. AM, on the other hand, is widely used in broadcast transmission with long, short, or medium wave bands. It is also used in air radio communications, high frequency radio links and quadrature amplitude modulation.

References

Poole, I. (n.d.). What is amplitude modulation?. Radio-Electronics. Retrieved from http://www.radio-electronics.com/info/rf-technology-design/am-amplitude-modulation/what-is-am-tutorial.php
Poole, I. (n.d.). Frequency modulation advantages and disadvantages. Radio-Electronics. Retrieved from http://www.radio-electronics.com/info/rf-technology-design/fm-frequency-modulation/advantages-disadvantages.php