ABSTRACT
We begin with an overview of applications of signal processing and the variety of sensing modalities that are employed. It is typical of remotesensing problems that what we want is not what we can measure directly, and we must obtain our information by indirect means. To illustrate that point without becoming entangled in the details of any particular application, we present a marbles-in-bowls model of remote sensing that, although simple, still manages to capture the dominate aspects of many real-world problems.
