Spectrum analyzers today and tomorrow: part 1 towards filterbanks-enabled real-time spectrum analysis

This is Part 1 of a two-part article on spectrum analyzer technology and the future capabilities enabled by introducing filterbanks. A spectrum analyzer (SA) is the primary tool for studying the spectral composition of many electrical, acoustic or optical waveforms. It displays a power spectrum over a given frequency range, changing the display as the properties of the signal change. Today, it is an essential element of the engineer´s toolbox. In this part, we will start by reviewing SA architectures in an historical perspective. The architectures and working principles of swept based and Fast Fourier Transform (FFT)-based SAs are discussed. Then, we zoom in on the so-called Real-Time Spectrum Analyzers (RTSA) and discuss the more significant performance criteria as a function of the measurement problem at hand. In the last section, we discuss several applications made possible by RTSA. The extension of RTSA with filterbanks is the main topic of Part 2 of this article which will appear in the December 2013 issue of the IEEE Instrumentation and Measurement Magazine.