Fundamentals of Dynamic Signal Analysis

This note is a primer for those who are unfamiliar with the advantages of analysis in the frequency and modal domains and with the class of digitizers and analyzers designed for Dynamic Signal Analysis.

The traditional way of observing signals is to view them in the time domain. The time domain is a record of what happened to a parameter of the system versus time. It was shown over one hundred years ago by Baron Jean Baptiste Fourier that any waveform that exists in the real world can be generated by adding up sine waves. By picking the amplitudes, frequencies and phases of these sine waves correctly, we can generate a waveform identical to our desired signal. Since we know that each line represents a sine wave, we have uniquely characterized our input signal in the frequency domain. This frequency domain representation of our signal is called the spectrum of the signal. Each sine wave line of the spectrum is called a component of the total signal. It is very important to understand that we have neither gained nor lost information, we are just representing it differently. We are looking at the same three dimensional graph from different angles. This different perspective can be very useful.