New measurement technique expands Agilent's leadership and excellence in noise figure analysis

摘要

Near the front end of any RF or microwave receiver is a key component known as a low-noise amplifier (LNA). The purpose of this amplifier is to amplify incoming signals while adding as little additional noise as possible. The sensitivity of the receiver (its ability to discriminate signals from the ambient noise) is often determined by the quality of the LNA.rnA key figure of merit that describes how much or how little additional noise is added is called the noise factor. The noise factor (F) of a network is defined as the input signal-to-noise-ratio divided by the output signal-to-noise-ratio [F = (S_i/N_i)/(S_o/N_o)]. For any real-world amplifier, the signal-to-noise-ratio at the output will always be smaller than that at the input, so F is always greater than one.