Rohde & Schwarz Introduces Distortion Analysis Software
Rohde & Schwarz has introduced the R&S FS K130 distortion analysis software for optimizing active RF components such as power amplifiers and mixers. This software allows users to characterize and linearize amplifiers quickly and easily and even compensates for memory effects exhibited by many of today's amplifiers. The test setup consists of a spectrum analyzer, a signal generator and a PC. The setup measures the amplifier's characteristics and calculates the correction required to attain a linear output signal.
The R&S FS-K130 distortion analysis software is said to be ideal for analyzing active components such as RF amplifiers, mixers, and converters used in telecommunications equipment, civil and military communications systems, and mobile phones.
The application, which runs on Windows XP, was designed for a test setup based on the R&S FSV or R&S FSQ spectrum analyzers as well as the R&S SMBV or R&S SMU200A signal generators. The software has two functions. It controls the instruments and it characterizes the amplifier using the same signal waveform that will be driving the amplifier. The spectrum analyzer captures and records the amplifier's output signal.
The software uses this information to calculate a model that describes the signal's characteristics, including amplifier distortion. Based on the calculated amplifier model, the software determines a corresponding model that is used to predistort the input signal. Predistortion improves both the Error Vector Magnitude (EVM) and the Adjacent Channel Leakage Ratio (ACLR). The improvement can be measured using a calculated, predistorted input signal prepared by the software.