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=== Gain===
An amplifier’s output/input magnitude ratio is gain. In RF, the gain is generally specified in logarithmic scale (dB).
[[File:GainAmpAmp1.pnggif|frame|center]]
=== SNR (Signal to Noise Ratio) ===
The ratio of signal power to the noise power, often expressed in decibels.
[[File:SNRAmpAmp2.pnggif|frame|center]]
=== NF (Noise Figure) ===
It is measures of degradation of the SNR, caused by components in a RF signal chain.
[[File:NFAmpAmp3.pnggif|frame|center]]
=== Bandwidth ===
Noise figure of a component has been defined above. But one can also define the noise figure of a system consisting of multiple components connected in series. NF of this kind of system is define in a very similar way as above with SNRin is the SNR of input to the system and SNRout is the SNR of the output of the system. <br \>
If we know the individual noise figures, we can calculate the noise figure of the system using this formula,
[[File:NFsystemAmp4.pnggif|frame|center]]where Fn is the noise factor for the n-th device, and Gn is the power gain (linear, not in dB) of the n-th device.
=== Need of LNA ===
| Generates a lot of heat. Heat sinks necessary.
|}
''The values in the table are take from datasheets for LNA from Analog Devices (ADL5523) and Power Amplifier RF5110G.''
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