Contents
- 1 Why frequency multiplier is used in frequency modulation?
- 2 What is the effect of increasing modulation index in FM?
- 3 What is the modulation index of an FM signal if the frequency is doubled?
- 4 What is the commercial FM frequency range?
- 5 What is theoretical bandwidth of FM?
- 6 Which is an example of the FM modulation index?
- 7 When to use a wideband FM frequency modulation?
- 8 How is the frequency spectrum of a FM signal approximated?
Why frequency multiplier is used in frequency modulation?
Frequency multipliers consist of a nonlinear circuit that distorts the input signal and consequently generates harmonics of the input signal. Some modulation schemes, such as frequency modulation, survive the nonlinear distortion without ill effect (but schemes such as amplitude modulation do not).
What is the effect of increasing modulation index in FM?
As the modulation index increases for frequency modulation (FM), the number of significant sidebands increases, but the sidebands’ total average power remains constant.
What is frequency sensitivity in FM?
A sinusoidal modulating waveform of amplitude 5 V and a frequency of 2 KHz is applied to FM generator, which has a frequency sensitivity of 40 Hz/volt.
What is the modulation index of an FM signal if the frequency is doubled?
When the modulating frequency is doubled, the modulation index is halved and the modulating voltage constant the modulation system is.
What is the commercial FM frequency range?
For example, commercial stereo FM broadcasting (88–108 MHz) is assigned a bandwidth of 200 kHz in which to broadcast 15 kHz of audio-music bandwidth. One speaks of FM trading bandwidth for noise.
What is the frequency range of FM?
88 to 108 MHz
FM radio stations are usually assigned a frequency in the range of 88 to 108 MHz in contrast to AM radio which is in the range of 0.55 to 1.6 MHz, and this is one reason why AM radio has a longer range; however, FM radio operates better in reception areas that are closed in, such as tunnels and buildings, owing to the …
What is theoretical bandwidth of FM?
Thus the theoretical bandwidth of FM is infinite. An infinite bandwidth signal would be very difficult to transmit. Fortunately, the higher order sidebands in FM have extremely low amplitude and may be ignored.
Which is an example of the FM modulation index?
The FM modulation index is equal to the ratio of the frequency deviation to the modulating frequency. To give an example of the FM modulation index, take the example where a signal has a deviation of ±5kHz, and the modulating frequency is 1kHz, then the modulation index for this particular instance is 5 / 1 = 5.
How does frequency multiplication affect the final frequency?
How the frequency multiplication is implemented will affect the quality of the final frequency (i.e. phase noise/jitter). What follows is a review of some multipli- ers, and the reader is encouraged to use the Reference list for more specific design details.
When to use a wideband FM frequency modulation?
Wideband FM: Wideband FM is typical used for signals where the FM modulation index is above about 0.5. For these signals the sidebands beyond the first two terms are not insignificant. For these signals the sidebands beyond the first two terms are not insignificant.
How is the frequency spectrum of a FM signal approximated?
The frequency spectrum of an actual FM signal has components extending infinitely, although their amplitude decreases and higher-order components are often neglected in practical design problems. Mathematically, a baseband modulating signal may be approximated by a sinusoidal continuous wave signal with a frequency fm.