A low-noise amplifier (LNA) is an electronic device designed to amplify weak signals while minimizing the addition of noise. It is commonly used in communication systems, such as radio receivers and satellite communications, where preserving signal integrity is crucial. LNAs help improve the overall performance of these systems by ensuring that the desired signal can be detected even in the presence of background noise. These amplifiers are typically characterized by their low noise figure, which quantifies how much noise they add to the signal. LNAs are often implemented using transistors or integrated circuits and are essential in applications like wireless communication and medical imaging, where accurate signal processing is vital.