One of the most important building blocks of radio frequency systems is Low Noise Amplifier. Low noise amplifiers (LNAs) play a key role in radio receiver performance. The low noise amplifier is a particular type of electronic amplifier used in communication systems, which amplifies very weak signals captured by an antenna. A proper LNA design should provide a minimum noise figure (NF). Moreover, it should also deliver a significant gain to minimize noise contribution of the subsequent stages and to amplify the attenuated signal received by the antenna so that it can be efficiently handled by the following stages (mixer, VGA, etc.).
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