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In frequency modulation what happens to the bandwidth when you increase the modulating frequency?
Bandwidth increases as a function of both modulating frequencyand deviation. As deviation increases, pairs of sidebands are generated, each equal to fc+m and fc-m, fc+2m, fc-2m etc. where fc = the carrier frequency and m = the modulating frequency. Increasing modulation (frequency deviation) will change the level of each of the sideband pairs - and the carrier, which at times falls to zero.
What else can I help you with?
Is The carrier frequency is usually lower than the modulating frequency?
when the frequency is low , energy will be obviously low. To increase the energy of the signal we need to increase the frequency. This is achieved by multiplying the message signal with the carrier signal (with high frequency).
Why high frequency signal is more affected by noise compare to low frquency signal?
AS FREQUENCY INCREASE THE BANDWIDTH INCREASE. AS WE KNOW NOISE HAVE LARGER BANDWIDTH. SO ITS AFFECT HIGH FREQUENCY SIGNAL. BUT LOW FREQUENCY SIGNAL HAVE LOW BANDWIDTH SO IT IS LESS AFFECTED BY NOISE. ALSO WE KNOW QUALITY FACTOR= CUTOFF FREQUENCY / BANDWIDTH. SO AS FREQUENCY INCREASE B.W. INCREASE SO QUALITY DEGRADE. CUTOFF FREQUNCY AND THE TERM FREQUENCY (USED HERE) IS DIFFERENT. CUTTOFF FREQUNCY IS USED IN FILTER. PRABIR KUMAR SETHY prabirsethy.05@gmail.com
What increase in horizontal resolution is possible if a bandwidth of 5 MHz is used in a video signal?
The horizontal resolution in a video signal can be estimated using the formula that relates bandwidth to resolution, where the bandwidth in MHz typically allows for a resolution of about 10 to 12 times the bandwidth in kilohertz. Therefore, with a bandwidth of 5 MHz, the horizontal resolution could be increased to approximately 500 to 600 pixels. This is a general approximation and can vary based on the specific modulation and encoding techniques used.
What is 16-ary modulation?
16-ary modulation is a digital modulation scheme that uses 16 distinct symbols to represent data. Each symbol can encode 4 bits of information, allowing for more efficient use of bandwidth compared to simpler modulation schemes like binary or quadrature amplitude modulation (QAM). This technique is often employed in communication systems to increase data rates while maintaining a reasonable level of signal integrity. Common examples include 16-QAM, where the symbols are arranged in a square constellation diagram.
Principle of peak AGC system?
A peak-based AGC system, such as is required for SSB, will reduce the receiver gain by 6 dB as the modulating percentage increases from 0% to 100%. A receiver with a peak-responding AGC system will, in theory, cause a gain reduction as modulation percentage increases and a gain increase as the modulation level decreases. (Thanks to Clifton Laboratories 7236 Clifton Road Clifton VA 20124 tel: (703) 830 0368 fax: (703) 830 0711 E-mail: Jack.Smith@cliftonlaboratories.com)
Is The carrier frequency is usually lower than the modulating frequency?
when the frequency is low , energy will be obviously low. To increase the energy of the signal we need to increase the frequency. This is achieved by multiplying the message signal with the carrier signal (with high frequency).
Why high frequency signal is more affected by noise compare to low frquency signal?
AS FREQUENCY INCREASE THE BANDWIDTH INCREASE. AS WE KNOW NOISE HAVE LARGER BANDWIDTH. SO ITS AFFECT HIGH FREQUENCY SIGNAL. BUT LOW FREQUENCY SIGNAL HAVE LOW BANDWIDTH SO IT IS LESS AFFECTED BY NOISE. ALSO WE KNOW QUALITY FACTOR= CUTOFF FREQUENCY / BANDWIDTH. SO AS FREQUENCY INCREASE B.W. INCREASE SO QUALITY DEGRADE. CUTOFF FREQUNCY AND THE TERM FREQUENCY (USED HERE) IS DIFFERENT. CUTTOFF FREQUNCY IS USED IN FILTER. PRABIR KUMAR SETHY prabirsethy.05@gmail.com
What are the advantages and disadvantages of phase modulation?
Advantage - 1. Phase modulation & demodulation is easy compared to Frequency modulation. 2. Phase modulator is used in determining velocity of moving target by extracting Doppler information. Doppler information needs stable carrier which is possible in phase modulation but not in frequency modulation. Disadvantage - 1. Phase ambiguity comes if we exceed its modulation index pi radian(180 degree). 2. we need frequency multiplier to increase phase modulation index. Visit my website http://harshit.org
Why FM have infinte number of sidebands?
It can't. FM (like broadcast AM) has two *sidebands*, one at a higher frequency than the transmitter's carrier, one at a lower frequency. The modulating signal (voice, music, etc) of any trasnmitter creates one or more pairs of side frequencies within the two sidebands. A broadcast AM signal can only produce two side frequencies, so an AM transmitter at 1.5 MHz, with a 1 kHz modulating tone (fm), would put out its carrier (fc) at 1.5 MHz, a lower side frequncy at (1.5 - 0.001) = 1.499 MHz, then its carrier at 1.5 MHz, and then the upper side frequency at (1.5 + 0.001) = 1.501 MHz. The AM signal can never be wider than twice the highest modulating frequency (fm), spanning from (fc - fm) to (fc + fm), a span of 2 x fm. Be aware that special-purpose AM systems can generate just *one* sideband - we won't go into that amount of detail apart from noting it. FM signals can be wider than twice the highest modulating frequency. The complete analysis needs the mathematical Fourier Transform, but we can think of it this way. Stronger frequency modulation shows up as a larger change in the transmitted signal frequency. An FM signal at 100 MHz, modulated by a 1 KHz tone, *can* put out a lower side frequency at (100 - 0.001) = 99.999 MHz and an upper side frequency at (100 + 0.001) = 100.001 MHz. You could receive this just fine, but it would sound "weak" compared to normal broadcasts. It's possible to increase the frequency shift to (say) five times. Now, the sidebands must extend from (100 - 5x0.001) = 99.995 MHz to (100 + 5x0.001) = 100.005 MHz. How do we account for the original 1 KHz tone creating a bandwidth of 2x5 kHz? The answer is that we actually have *five* lower side frequencies, at -5, -4, -3, -2, -1 kHz below the carrier, and *five* upper side frequencies at +1, +2, +3 +4 and +5 kHz above the carrier. Notice that they are multiples of the original 1 kHz modulating frequency. These can, in fact, be shown on the instrument called a spectrum analyser. Your question? As with broadcast AM, an FM signal has only two sidebands. In FM, the strength of modulation (the modulation index) controls the number of individual side frequencies, and thus the total bandwidth of the signal. Can an FM signal have *infinite* numbers of side frequencies? Not really. It can have a *very large* number of side frequencies with very great modulation strength. In practice, this would take up *a lot* of the FM radio band, so broadcast FM commonly uses a maximum modulation index of 5.0. This means that a fully-modulating 15 kHz signal would give a bandwidth of -(15 x 5) to +(15 x 5) kHz, which is +/- 75 kHz.
How can the Doppler effect cause broadening of a spectral line?
Perhaps this broadening of the spectral line might be due to different propogation speeds under Doppler conditions when the emitting object is moving towards us? Therefore increasing the frequency shift and spreading the spectrum over a wider bandwidth. Or perhaps Take an amplitude modulated carrier wave with a fixed modulating frequency. Un-shifted the sidebands would remain constant in width. If the signal source was moving towards us the modulating frequency would also increase. The increased modulating frequency would move the sidebands further away from the carrier, increasing bandwidth or broadening the spectrum.
Why fsk does not used for high speed mode?
Frequency Shift Keying (FSK) is generally not used for high-speed data transmission because it requires a larger bandwidth compared to other modulation techniques like Phase Shift Keying (PSK) or Quadrature Amplitude Modulation (QAM). The inherent nature of FSK, which relies on shifting between discrete frequencies, can limit the data rate and increase susceptibility to noise and interference. Additionally, as data rates increase, the frequency separation needed for reliable detection may become impractical, leading to reduced efficiency and performance in high-speed applications.
Why in gsm we are taking 200kHz as bandwidth why we cant take 100kHz or some thing less than 200kHz so that we can increase the ARFCNs?
In GSM, a bandwidth of 200 kHz is chosen to balance the needs for voice quality, capacity, and interference management. While a smaller bandwidth like 100 kHz could technically increase the number of available ARFCNs (Absolute Radio Frequency Channel Numbers), it would compromise voice quality and increase the likelihood of interference between channels. The 200 kHz allocation allows for sufficient guard bands and accommodates the modulation techniques used, ensuring effective communication and maintaining service reliability.
What increase in horizontal resolution is possible if a bandwidth of 5 MHz is used in a video signal?
The horizontal resolution in a video signal can be estimated using the formula that relates bandwidth to resolution, where the bandwidth in MHz typically allows for a resolution of about 10 to 12 times the bandwidth in kilohertz. Therefore, with a bandwidth of 5 MHz, the horizontal resolution could be increased to approximately 500 to 600 pixels. This is a general approximation and can vary based on the specific modulation and encoding techniques used.
How control dc motor using micro controller?
The speed of the motor depends on load, voltage and current. The speed can be maintain by using a method called Pulse code modulation (PWM). By changing (modulating) the width of the pulse applied to the DC motor we can increase or decrease the amount of power provided to the motor, there by increasing or decreasing the motor speed. mean we have to just change the duty cycle of modulating output.
How to increase the bandwidth on an Android phone?
You cannot increase the bandwidth on an Android phone.
How do you reduce congestion?
Increase the bandwidth.
How do you increase bandwidth speed for xp home edition?
http://dummy-essentials.blogspot.com/2009/07/increase-bandwidth-by-20.html
