An important concept in many communications applications is the correlation between two...

An important concept in many communications applications is the correlation between two signals. In the problems at the end of Chapter 2, we will have more to say about this topic and will provide some indication of how it is used in practice. For now, we content ourselves with a brief introduction to correlation functions and some of their properties.

The function i usually referred to as the auto correlation function of the signal is often called a cross-correlation function.