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Why does FM take much more bandwidth than AM?
FM uses a higher frequency range and a bigger bandwidth than AM. Each FM station is allocated 150 kHz of bandwidth, which is 15 times that of an AM station. This means that an FM station can transmit 15 times as much information as an AM station and explains why music sounds so much better on FM.
Why does FM need high bandwidth?
However, FM signals are impacted by physical barriers. FM has better sound quality due to higher bandwidth. Twice the sum of the modulating signal frequency and the frequency deviation. If the frequency deviation is 75kHz and the modulating signal frequency is 15kHz, the bandwidth required is 180kHz.
Which is more bandwidth efficient AM or FM?
AM has poorer sound quality, and a lower bandwidth but is cheaper and can be transmitted over long distances as it has a lower bandwidth that is why it can hold more stations available in any frequency range. FM is less affected by interference, but FM signals are impacted by physical barriers.
What is the bandwidth of AM and FM?
| Difference Between AM and FM | |
|---|---|
| Amplitude Modulation (AM) | Frequency Modulation (FM) |
| Has poor sound quality, but can transmit longer distance | Has higher bandwidth with better sound quality |
| The frequency range of AM radio varies from 535 to 1705 kHz | The frequency range of FM is 88 to 108 MHz in the higher spectrum |
Why do FM waves have a greater bandwidth than AM?
The sideband structure of the FM signal is more complex than that of the AM signal. For FM broadcasting the audio bandwidth is 15 kHz. However, the benefits which FM broadcasting is capable of providing are not achieved unless the occupied bandwidth is significantly greater than the minimum possible.
What is the bandwidth of an AM radio station?
If the station only transmits analog, then the sidebands must drop off sharply around 10 kHz away from the carrier for an RF bandwidth of about 20 kHz. At least in the United States, AM radio stations are allowed to broadcast signals that are narrower in bandwidth than the maximum.
What is the occupied bandwidth for FM radio?
The occupied bandwidth for FM is thus at least partly a legal requirement. The reason different FM systems have different bandwidths is so that to maximize the efficiency of the intended usage. For business band and VHF/UHF amateur radio the bandwidth is either 5 or 10 kHz. For FM broadcast it is 100 kHz.
Why do FM stations sound better than AM stations?
This explains why FM stations sound better than AM stations, but AM stations can be heard from further away. AM radio varies the amplitude of the broadcast signal so the power at which that signal is broadcast is also changed, since amplitude represents the strength of the signal. Some receivers can’t pick up low amplitude signals at all.