When a wide band of frequencies is transmitted simultaneously, each frequency will vary in the amount of fading. What is this variable fading called?

When a wide band of frequencies is transmitted simultaneously, each frequency will vary in the amount of  fading. What is this variable fading called?
by

1 Answer

Answer :

Selective fading.
by

Related questions

What transmitter component allows the radiation of a large number of discrete frequencies over a wide band?

Description : What transmitter component allows the radiation of a large number of discrete frequencies over a wide band?

Last Answer : . Frequency synthesizer.

What device sweeps a band of frequencies to determine frequencies and amplitudes of each frequency component?

Description : What device sweeps a band of frequencies to determine frequencies and amplitudes of each frequency component?

Last Answer : Spectrum analyzer.

ECE Board Exam March 1996 An antenna which is not resonant at a particular frequencies and so can be used over a wide band of frequencies and so can be used over a wide band of frequencies is called A. aperiodic B. boresight C. cassegrain D. top-loaded

Description : ECE Board Exam March 1996 An antenna which is not resonant at a particular frequencies and so can be used over a wide band of frequencies and so can be used over a wide band of frequencies is called A. aperiodic B. boresight C. cassegrain D. top-loaded

Last Answer : A. aperiodic

What is the band of frequencies called that is included between the two points at which current falls to 70 percent of its maximum value in a resonant circuit?

Description : What is the band of frequencies called that is included between the two points at which current falls to 70 percent of its maximum value in a resonant circuit?

Last Answer : Bandwidth of the circuit

What type filter is used to block the passage of current for a narrow band of frequencies, while allowing current to flow at all frequencies above or below this band?

Description : What type filter is used to block the passage of current for a narrow band of frequencies, while allowing current to flow at all frequencies above or below this band?

Last Answer : . Band-reject.

What type filter is used to allow a narrow band of frequencies to pass through a circuit and attenuate all other frequencies above or below the desired band?

Description : What type filter is used to allow a narrow band of frequencies to pass through a circuit and attenuate all other frequencies above or below the desired band?

Last Answer : Bandpass.

What is the method of diversity reception where the signal is transmitted on 2 different frequencies over the same path? A. Quadruple B. Frequency C. Polarization D. Space

Description : What is the method of diversity reception where the signal is transmitted on 2 different frequencies over the same path? A. Quadruple B. Frequency C. Polarization D. Space

Last Answer : B. Frequency

What is the device called that will separate alternating current from direct current, or that will separate alternating current of one frequency from other alternating currents of different frequencies?

Description : What is the device called that will separate alternating current from direct current, or that will separate alternating current of one frequency from other alternating currents of different frequencies?

Last Answer : A filter.

Emission on a frequency or frequencies immediately outside the necessary bandwidth which result from the modulation process except spurious emission. A. Radiation B. Noise C. Out of the band D. Interference

Description : Emission on a frequency or frequencies immediately outside the necessary bandwidth which result from the modulation process except spurious emission. A. Radiation B. Noise C. Out of the band D. Interference

Last Answer : C. Out of the band

What range of frequencies are usually referred to as the Ultra High Frequency (UHF) Band? w) 3 to 30 Mega Hertz x) 30 to 300 Mega Hertz y) 300 to 3,000 Mega Hertz z) 30,000 to 300,000 Mega Hertz

Description : What range of frequencies are usually referred to as the Ultra High Frequency (UHF) Band? w) 3 to 30 Mega Hertz x) 30 to 300 Mega Hertz y) 300 to 3,000 Mega Hertz z) 30,000 to 300,000 Mega Hertz

Last Answer : ANSWER: Y -- 300 to 3,000 MEGA HERTZ

In a typical mobile phone system with hexagonal cells, it is forbidden to reuse a frequency band in adjacent cells. If 840 frequencies are available, how many can be used in a given cell? (A) 280 (B) 210 (C) 140 (D) 120

Description : In a typical mobile phone system with hexagonal cells, it is forbidden to reuse a frequency band in adjacent cells. If 840 frequencies are available, how many can be used in a given cell? (A) 280 (B) 210 (C) 140 (D) 120

Last Answer : Answer: A Explanation: Each cell has six other adjacent cells, in a hexagonal grid. If the central cell uses frequency group A, its six adjacent cells can use B, C, B, C, B, and C respectively. In other words, only 3 unique cells are needed. So the answer is 840/3 = 280 frequencies.

Which of the following statements is not true with respect to microwaves? (A) Electromagnetic waves with frequencies from 300 GHz to 400 THz. (B) Propagation is line-of-sight. (C) Very high-frequency waves cannot penetrate walls. (D) Use of certain portions of the band requires permission from authorities.

Description : Which of the following statements is not true with respect to microwaves? (A) Electromagnetic waves with frequencies from 300 GHz to 400 THz. (B) Propagation is line-of-sight. (C) Very ... waves cannot penetrate walls. (D) Use of certain portions of the band requires permission from authorities.

Last Answer : (A) Electromagnetic waves with frequencies from 300 GHz to 400 THz.

A cavity that vibrates at its natural frequency produces a louder sound than at other frequencies. What term is used to describe this phenomenon?

Description : A cavity that vibrates at its natural frequency produces a louder sound than at other frequencies. What term is used to describe this phenomenon?

Last Answer : Resonance.

What term is used to describe the frequency at which the filter circuit changes from the point of rejecting the unwanted frequencies to the point of passing the desired frequencies?

Description : What term is used to describe the frequency at which the filter circuit changes from the point of rejecting the unwanted frequencies to the point of passing the desired frequencies?

Last Answer : Frequency cutoff (fco).

A tube has a transconductance of 800 mhos and a load resistor of 50 kohms. When control grid voltage varies by 6 volts, the plate voltage will vary by what amount?

Description : A tube has a transconductance of 800 mhos and a load resistor of 50 kohms. When control grid voltage varies by 6 volts, the plate voltage will vary by what amount?

Last Answer : 240 volts.

If the mu of a tube is 85 and the signal at the control grid is 4 volts ac, the plate voltage will vary by what amount?

Description : If the mu of a tube is 85 and the signal at the control grid is 4 volts ac, the plate voltage will vary by what amount?

Last Answer : 340 volts.

What is one of the major reasons for the fading of radio waves which have been reflected from a surface?

Description : What is one of the major reasons for the fading of radio waves which have been reflected from a surface?

Last Answer : Shifting in the phase relationships of the wave.

There is a maximum frequency at which vertically transmitted radio waves can be refracted back to Earth. What is this maximum frequency called?

Description : There is a maximum frequency at which vertically transmitted radio waves can be refracted back to Earth. What is this maximum frequency called?

Last Answer : Critical frequency.

What factor determines the difference between the transmitted frequency and the received frequency in an fm transmitter?

Description : What factor determines the difference between the transmitted frequency and the received frequency in an fm transmitter?

Last Answer : Travel time.

Three coins are tossed simultaneously 200 times with the following frequencies of different outcomes ; -Maths 9th

Description : Three coins are tossed simultaneously 200 times with the following frequencies of different outcomes ; -Maths 9th

Last Answer : Total number of chances = 23 + 72 + 77 + 28 = 200 Number of chances of coming 2 heads = 72 therefore P( coming 2 heads)= 514 / 642 = 9 / 25

Three coins are tossed simultaneously 200 times with the following frequencies of different outcomes -Maths 9th

Description : Three coins are tossed simultaneously 200 times with the following frequencies of different outcomes -Maths 9th

Last Answer : It is given that coin is tossed 200 times Total number of trials = 200 Number of events for getting less than three tails = 68 + 82 + 30 = 180 Probability of getting less than 3 tails =180 / 200 =9 / 10

Three coins are tossed simultaneously 200 times with the following frequencies of different outcomes ; -Maths 9th

Description : Three coins are tossed simultaneously 200 times with the following frequencies of different outcomes ; -Maths 9th

Last Answer : Total number of chances = 23 + 72 + 77 + 28 = 200 Number of chances of coming 2 heads = 72 therefore P( coming 2 heads)= 514 / 642 = 9 / 25

Three coins are tossed simultaneously 200 times with the following frequencies of different outcomes -Maths 9th

Description : Three coins are tossed simultaneously 200 times with the following frequencies of different outcomes -Maths 9th

Last Answer : It is given that coin is tossed 200 times Total number of trials = 200 Number of events for getting less than three tails = 68 + 82 + 30 = 180 Probability of getting less than 3 tails =180 / 200 =9 / 10

In a variable speed induction motor derive V/f kept constant over a wide range of its frequency variation. ...

Description :  In a variable speed induction motor derive V/f kept constant over a wide range of its frequency variation. The motor operates in the following mode : -  a) Constant power mode b) Constant torque mode c) Constant slip mode d) Variable power and variable torque mode

Last Answer :  In a variable speed induction motor derive V/f kept constant over a wide range of its frequency variation. The motor operates in the following mode : - Constant torque mode

Compare narrow band FM with wide-band FM w.r.t. following points. (i) Modulation index (ii) Maximum deviation (iii)Range of modulating frequency (iv)Application

Description : Compare narrow band FM with wide-band FM w.r.t. following points. (i) Modulation index (ii) Maximum deviation (iii)Range of modulating frequency (iv)Application

Last Answer : Sr. No Parameters Narrow band FM Wide band FM 1 Modulation index Less than or slightly greater than 1 Greater than 1  2 Maximum deviation ... like police wireless, ambulance etc. Entertainment broadcasting can be used for high quality music transmission 

When the frequency is decreased so that two quarter wavelengths are longer than the "a" (wide) dimension of the waveguide, what will happen?

Description : When the frequency is decreased so that two quarter wavelengths are longer than the "a" (wide) dimension of the waveguide, what will happen?

Last Answer : Energy will no longer pass through the waveguide.

What causes the maximum usable frequency to vary? A. The temperature of the ionosphere B. The speed of the winds in the upper atmosphere C. The type of weather just below the ionosphere D. The amount of radiation received from the sun

Description : What causes the maximum usable frequency to vary? A. The temperature of the ionosphere B. The speed of the winds in the upper atmosphere C. The type of weather just below the ionosphere D. The amount of radiation received from the sun

Last Answer : D. The amount of radiation received from the sun

The best solution to fading is _____. A. space diversity B. frequency diversity C. polarization diversity D. wavelength diversity

Description : The best solution to fading is _____. A. space diversity B. frequency diversity C. polarization diversity D. wavelength diversity

Last Answer : A. space diversity

Define the terms: 1) Maximum usable frequency 2) Fading

Description : Define the terms: 1) Maximum usable frequency 2) Fading

Last Answer : 1)Maximum usable frequency:- Maximum usable frequency is defined as the limiting frequency ,when the angle of incidence is other than the normal . OR The highest frequency that can be used for sky ... which left the same source but arrived at the destination by different paths is known as fading.

Compare sky wave and space wave propagation w.r.t. following points. (i) Frequency range (ii) Effect of fading (iii)Polarization (iv)Application

Description : Compare sky wave and space wave propagation w.r.t. following points. (i) Frequency range (ii) Effect of fading (iii)Polarization (iv)Application

Last Answer : Sr. No  Parameters Sky Wave Propagation Space Wave Propagation 1 Frequency range 3 MHz to 30 MHz  Above 30 MHz 2 Effect of fading Problem of fading is ... horizontally Polarized 4 Application RadioBroadcasting (SW Range) Used for TV and FM broadcasting

In which transmission are sound and video signals transmitted simultaneously?

Description : In which transmission are sound and video signals transmitted simultaneously?

Last Answer : – T.V. Transmission

In which transmission are sound and video signals transmitted simultaneously?

Description : In which transmission are sound and video signals transmitted simultaneously?

Last Answer : T.V. Transmission

What is the usualnumber of bits transmitted simultaneously inparalleldata transmission used by microcomputers? A. 16 B. 9 C. 8 D. 4 E. None of the above

Description : What is the usualnumber of bits transmitted simultaneously inparalleldata transmission used by microcomputers? A. 16 B. 9 C. 8 D. 4 E. None of the above

Last Answer : 9

Clausius-Clapeyron Equation gives accurate result, when the (A) Vapour pressure is relatively low and the temperature does not vary over wide limits (B) Vapour obeys the ideal gas law and the latent heat of vaporisation is constant (C) Volume in the liquid state is negligible compared with that in the vapour state (D) All (A), (B) and (C)

Description : Clausius-Clapeyron Equation gives accurate result, when the (A) Vapour pressure is relatively low and the temperature does not vary over wide limits (B) Vapour obeys the ideal gas law and the latent heat of ... is negligible compared with that in the vapour state (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

. Which type of variable resistor should you select for controlling a large amount of current?

Description : . Which type of variable resistor should you select for controlling a large amount of current?

Last Answer : The rheostat.

In research, something that does not "vary" is called a ___________. a. Variable b. Method c. Constant d. control group

Description : In research, something that does not "vary" is called a ___________. a. Variable b. Method c. Constant d. control group

Last Answer : d. control group

In a conductor – (1) there is no conduction band (2) the forbidden energy gap is very wide (3) the forbidden energy gap is very narrow (4) the valence band and the conduction band overlap each other

Description : In a conductor – (1) there is no conduction band (2) the forbidden energy gap is very wide (3) the forbidden energy gap is very narrow (4) the valence band and the conduction band overlap each other

Last Answer : (4) the valence band and the conduction band overlap each other Explanation: In the case of a conductor, there is no forbidden energy gap. The conduction and valence energy bands overlap ... , the electrons from the valence band can freely enter the conduction energy band. Conduction energy band

In a conductor (1) there is no conduction band (2) the forbidden energy gap is very wide (3) the forbidden energy gap is very narrow (4) the valence band and the conduction band overlap each other

Description : In a conductor (1) there is no conduction band (2) the forbidden energy gap is very wide (3) the forbidden energy gap is very narrow (4) the valence band and the conduction band overlap each other

Last Answer : the valence band and the conduction band overlap each other

What is the filter called that passes low frequencies but rejects or attenuates high frequencies?

Description : What is the filter called that passes low frequencies but rejects or attenuates high frequencies?

Last Answer : Low-pass filter, high-frequency discriminator or high-frequency attenuator.

What is the filter called in which the low frequencies do not produce a useful voltage?

Description : What is the filter called in which the low frequencies do not produce a useful voltage?

Last Answer : High-pass filter, low-frequency discriminator, or low-frequency attenuator.

A data file of 1,00,000 characters contains only the characters g-l, with the frequencies as indicated in table: using the variable-length code by Huffman codes, the file can be encoded with (A) 2,52,000 bits (B) 2,64,000 bits (C) 2,46,000 bits (D) 2,24,000 bits

Description : A data file of 1,00,000 characters contains only the characters g-l, with the frequencies as indicated in table:  using the variable-length code by Huffman codes, the file can be encoded with (A) 2,52,000 bits (B) 2,64,000 bits (C) 2,46,000 bits (D) 2,24,000 bits

Last Answer : (D) 2,24,000 bits 

What is used to show how diode parameters vary over a full operating range?

Description : What is used to show how diode parameters vary over a full operating range?

Last Answer : A characteristic curve.

The plate voltage of a tube will vary 126 volts when a 3-volt ac signal is applied to the control grid. What is the gain of this tube?

Description : The plate voltage of a tube will vary 126 volts when a 3-volt ac signal is applied to the control grid. What is the gain of this tube?

Last Answer : 42.

Will an optical fiber's attenuation coefficient vary with changes in wavelength?

Description : Will an optical fiber's attenuation coefficient vary with changes in wavelength?

Last Answer : Yes.

How much must the fpa plate current vary to produce 100- percent modulation in a plate modulator?

Description : How much must the fpa plate current vary to produce 100- percent modulation in a plate modulator?

Last Answer : Between 0 and nearly two times its unmodulated value.

The band of frequencies least susceptible to atmospheric noise and interference is: A. 30 – 300 kHz B. 300 – 3000 kHz C. 3 – 30 MHz D. 300 – 3000 MHz

Description : The band of frequencies least susceptible to atmospheric noise and interference is: A. 30 – 300 kHz B. 300 – 3000 kHz C. 3 – 30 MHz D. 300 – 3000 MHz

Last Answer : D. 300 – 3000 MHz

What band of frequencies do these satellites operate? A. L band B. Ka band C. C band D. Ku band

Description : What band of frequencies do these satellites operate? A. L band B. Ka band C. C band D. Ku band

Last Answer : A. L band

Which band of frequencies used by military for its satellites and radar? A. C band B. X band C. L band D. P band

Description : Which band of frequencies used by military for its satellites and radar? A. C band B. X band C. L band D. P band

Last Answer : B. X band

Troposheric scatter uses the frequencies in the ________ band. A. VLF B. UHF C. VHF D. UF

Description : Troposheric scatter uses the frequencies in the ________ band. A. VLF B. UHF C. VHF D. UF

Last Answer : B. UHF

The ___________ filter attenuates signals but passes frequencies below and above that band. A. low pass B. band pass C. band stop D. high pass

Description : The ___________ filter attenuates signals but passes frequencies below and above that band. A. low pass B. band pass C. band stop D. high pass

Last Answer : C. band stop