## Noise Figure of Low Noise Amplifier Solution

STEP 0: Pre-Calculation Summary
Formula Used
Noise Figure = 1+((4*Source Impedance)/Feedback Resistance)+Noise Factor of Transistor
NF = 1+((4*Rs)/Rf)+γ
This formula uses 4 Variables
Variables Used
Noise Figure - (Measured in Decibel) - Noise Figure is a measure of how much noise the amplifier adds to the signal it is amplifying.
Source Impedance - (Measured in Ohm) - Source Impedance is the opposition to current flow that the source presents to the load.
Feedback Resistance - (Measured in Ohm) - Feedback Resistance is a resistance that is connected between the output of the amplifier and the input of the amplifier.
Noise Factor of Transistor - Noise Factor of Transistor is a measure of how much noise the transistor itself adds to the signal.
STEP 1: Convert Input(s) to Base Unit
Source Impedance: 23 Ohm --> 23 Ohm No Conversion Required
Feedback Resistance: 35 Ohm --> 35 Ohm No Conversion Required
Noise Factor of Transistor: 11.2 --> No Conversion Required
STEP 2: Evaluate Formula
Substituting Input Values in Formula
NF = 1+((4*Rs)/Rf)+γ --> 1+((4*23)/35)+11.2
Evaluating ... ...
NF = 14.8285714285714
STEP 3: Convert Result to Output's Unit
14.8285714285714 Decibel --> No Conversion Required
14.8285714285714 14.82857 Decibel <-- Noise Figure
(Calculation completed in 00.004 seconds)
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## < 14 Low-Noise Amplifiers and Mixers Calculators

Feedback Factor of Low Noise Amplifier
Feedback Factor = (Transconductance*Source Impedance-1)/(2*Transconductance*Source Impedance*Voltage Gain)
Return Loss of Low-Noise Amplifier
Return Loss = modulus((Input Impedance-Source Impedance)/(Input Impedance+Source Impedance))^2
Noise Figure of Low Noise Amplifier
Noise Figure = 1+((4*Source Impedance)/Feedback Resistance)+Noise Factor of Transistor
Gate to Source Voltage of Low Noise Amplifier
Gate to Source Voltage = ((2*Drain Current)/(Transconductance))+Threshold Voltage
Threshold Voltage of Low Noise Amplifier
Threshold Voltage = Gate to Source Voltage-(2*Drain Current)/(Transconductance)
Transconductance of Low Noise Amplifier
Transconductance = (2*Drain Current)/(Gate to Source Voltage-Threshold Voltage)
Drain Current of Low Noise Amplifier
Drain Current = (Transconductance*(Gate to Source Voltage-Threshold Voltage))/2
Voltage Gain of Low Noise Amplifier given DC Voltage Drop
Voltage Gain = 2*DC Voltage Drop/(Gate to Source Voltage-Threshold Voltage)
Load Impedance of Low Noise Amplifier
Load Impedance = (Input Impedance-(1/Transconductance))/Feedback Factor
Input Impedance of Low Noise Amplifier
Input Impedance = (1/Transconductance)+Feedback Factor*Load Impedance
Output Impedance of Low Noise Amplifier
Output Impedance = (1/2)*(Feedback Resistance+Source Impedance)
Source Impedance of Low Noise Amplifier
Source Impedance = 2*Output Impedance-Feedback Resistance
Drain Resistance of Low Noise Amplifier
Drain Resistance = Voltage Gain/Transconductance
Voltage Gain of Low Noise Amplifier
Voltage Gain = Transconductance*Drain Resistance

## Noise Figure of Low Noise Amplifier Formula

Noise Figure = 1+((4*Source Impedance)/Feedback Resistance)+Noise Factor of Transistor
NF = 1+((4*Rs)/Rf)+γ

## What is a good noise figure for an LNA?

The ideal NF for an LNA depends on the specific application and the desired performance requirements. In general, NF values below 2 dB are considered good for LNAs, and values below 1 dB are considered excellent. For extremely sensitive applications, such as radio astronomy or medical imaging, NF values as low as 0.1 dB or lower may be required.

## How to Calculate Noise Figure of Low Noise Amplifier?

Noise Figure of Low Noise Amplifier calculator uses Noise Figure = 1+((4*Source Impedance)/Feedback Resistance)+Noise Factor of Transistor to calculate the Noise Figure, The Noise Figure of Low Noise Amplifier formula is defined as a measure of how much noise the amplifier adds to the signal it is amplifying. Noise Figure is denoted by NF symbol.

How to calculate Noise Figure of Low Noise Amplifier using this online calculator? To use this online calculator for Noise Figure of Low Noise Amplifier, enter Source Impedance (Rs), Feedback Resistance (Rf) & Noise Factor of Transistor (γ) and hit the calculate button. Here is how the Noise Figure of Low Noise Amplifier calculation can be explained with given input values -> 14.82857 = 1+((4*23)/35)+11.2.

### FAQ

What is Noise Figure of Low Noise Amplifier?
The Noise Figure of Low Noise Amplifier formula is defined as a measure of how much noise the amplifier adds to the signal it is amplifying and is represented as NF = 1+((4*Rs)/Rf)+γ or Noise Figure = 1+((4*Source Impedance)/Feedback Resistance)+Noise Factor of Transistor. Source Impedance is the opposition to current flow that the source presents to the load, Feedback Resistance is a resistance that is connected between the output of the amplifier and the input of the amplifier & Noise Factor of Transistor is a measure of how much noise the transistor itself adds to the signal.
How to calculate Noise Figure of Low Noise Amplifier?
The Noise Figure of Low Noise Amplifier formula is defined as a measure of how much noise the amplifier adds to the signal it is amplifying is calculated using Noise Figure = 1+((4*Source Impedance)/Feedback Resistance)+Noise Factor of Transistor. To calculate Noise Figure of Low Noise Amplifier, you need Source Impedance (Rs), Feedback Resistance (Rf) & Noise Factor of Transistor (γ). With our tool, you need to enter the respective value for Source Impedance, Feedback Resistance & Noise Factor of Transistor and hit the calculate button. You can also select the units (if any) for Input(s) and the Output as well. Let Others Know