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Generally power is expressed in watts. The gain is the ratio of the output power to the input power. Gain = (output power)/(input power) if the gain is expressed in terms of log(base10) it is known as Decibel power gain Decibel power gain = Log10(Gain)dB if 1milliwatt power is taken as reference then Decibel power gain = Log10(Output power/1 milliwatt)dBm
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Why do you use logarithm to calculate gain of amplifiers?
Audio engineers talk about the "JND", which stands for "just notiecable difference", which is a 3 decibel gain. That 3 decibel gain requires a doubling of amplifier power. For an amp to sound, subjectively, "twice as loud" requires a tenfold increase in power (300 watts instead of 30 watts).The decibel scale is logarithmic, not arithmetic.
Power gain of an amplifier having input gain of 20W and what is the output gain of 20mW?
The power gain of an amplifier having an input of 20W and an output of 20mW is 0.001. Expressed in decibels, that is a gain of -30db. (log2 0.001 * 3)If you meant an output power of 20MW (mega instead of milli), the gain is 1,000,000, or +60db.
Does Lucy Heartfilia gain Aquarius's water power?
She does; tho its not just an aquarius power. Its a power that works with all of her zodiac keys. Im not sure of all the details about it.
What is 3 dB?
3 dB is a way to describe the amount by which power increases when it doubles.1 dB = increase 26%2 dB = increase 58%3 dB = double4 dB = 2.51 times5 dB = 3.16 times6 dB = 4 times (3 dB + 3 dB = double double)7 dB = 5 times8 dB = 6.31 times9 dB = 8 times (3+3+3 = double double double)10 dB = 10 timesSimilarly-1 dB = decrease 26%-2 dB = decrease 58%-3 dB = halve-4 dB = decrease 2.51 times...etc...The equation is:dB change = 3 log2 ( final power / initial power )Edit:The more "official" equation used to compute a decibel Gain/Loss when comparing power values is this:GdB = 10*log10(Pout/Pin)Where GdB is the gain in power (if the value is negative, it means loss)and Pout is the power level seen at the outputand Pin is the power level seen at the inputAlso, 0 dB means no change in power.Note: If you're measuring an amplitude (like a Voltage or Current value), then the decibel equation increases by a factor of 2:GdB = 20*log10(Pout/Pin)So, to double an amplitude, a 6dB increase would be required.In other words, take the values at the top of this answer, and double the left side of the equation, and that's how it works with amplitudes.Lastly, it's important to understand that when multiplying in the linear world, you are adding in the decibel world. If you double a power level 2 times (e.g. 10 watts -> 20 watts -> 40 watts), you are multiplying 4 fold, but you are increasing by 6 dB (3dB + 3dB = 6dB).BUT if your talking about audio (sound) 1db is the smallest change in sound volume the human ear can detect.
If antenna is passive than how can it add gain?
Antennas provide so called passive gain, which means it comes from particular shape of the antennaThe gain of an antenna is a passive phenomenon - power is not added by the antenna, but simply redistributed to provide more radiated power in a certain direction than would be transmitted by an isotropic antenna. If an antenna has a gain greater than one in some directions, it must have a gain less than one in other directions, since energy is conserved by the antenna.SOURCE: wikipedia.com
Why do you use logarithm to calculate gain of amplifiers?
Audio engineers talk about the "JND", which stands for "just notiecable difference", which is a 3 decibel gain. That 3 decibel gain requires a doubling of amplifier power. For an amp to sound, subjectively, "twice as loud" requires a tenfold increase in power (300 watts instead of 30 watts).The decibel scale is logarithmic, not arithmetic.
The voltage gran of an amplifier is 200 The decibel voltage gain is?
The voltage gain of an amplifier is 200. The decibel voltage gain is? Answer Gain in dB = 20 * log 200 = 46 dB
What is the definition of decibel gain?
Turning up the volume
How much is a decibel?
A decibel (dB) has meaning only when compared a quantity (P1, V1, or I1) with a reference (P0, V0, or I0). Since it is a ratio of two like quantities, it is dimensionless. For a power ratio, power gain = 10 * log10(P1/Po) in [dB]. For a voltage ratio, voltage gain = 20 * log10(V1/Vo) in [dB]. For example, when P1 = 100 * P0, the power gain = 10 * log10(100) [dB] = 20 dB.
How you determine the absolute power gain in unitless and decibel (dB) when the input power level is 100mW and output power level is 20 watts?
The absolute power gain is the output power divided by the input power, in this case 20 / 0.1 or 200. In decibels this is 10 log 200 which is 23 dBs.
An RF amplifier amplifies the incoming signal by 200 times Calculate the power gain of this amplifier in dB?
If an RF amplifier amplifies the incoming signal by 200 times, the power gain of the amplifier is +25.9 dB. Power is proportional to voltage squared, so the power gain is 400. The decibel scale is 3 times log2 of the power change.
What is 36 decibel?
'decibel' means power level compared to something else. +36 dB = 3,981 times as much power as whatever it's compared to.
Is Decibel is the unit of power ratio?
It can be the power ratio. If you measure voltage or sound pressure it is not the power ratio.
What is Decibel level?
A unit used to measure the intensity of a sound or the power level of an electrical signal. Someones voice could raise by a decibel.
What is used to express gain of loss in a fiber optic system or component?
The decibel is used to express gain or loss relative to a known value. In fiber optics, the decibel is most commonly used to describe signal loss through the link after the light has left the transmitter.
How is sound mesaured?
Sound is measured in decibels. A decibel is 10logPower Out/Power In.
How the power levels are measured in communication system?
A: Dbm or decibel of modulation
