Software Receiver Design: Build Your Own Digital Communications System in Five Easy Steps is structured like a staircase with five simple steps. The first chapter presents a naive digital communications system, a sketch of the digital radio, as the first step. The second chapter ascends one step to fill in details and demystify various pieces of the design. Successive chapters then revisit the same ideas, each step adding depth and precision. The first functional (though idealized) receiver appears in Chapter 9. Then the idealizing assumptions are stripped away one by one throughout the remaining chapters, culminating in sophisticated receiver designs in the final chapters. Section 1.3 on page 12 outlines the five steps in the construction of the receiver and provides an overview of the order in which topics are discussed.