Overall the book can be divided into two main parts: one part consisting of Chapters 3 through 12 describing the fundamentals of how to make a radiometer system and leading up to another part consisting of Chapters 13 through 15 describing how to arrive at a system design from certain specifications, whether it is purely technical or whether it takes geophysical realities into account.

Chapter 3, "The Radiometer Receiver: Sensitivity and Accuracy," explains what a radiometer is, namely, a sensitive, calibrated microwave receiver. Radiometric sensitivity is defined and explained. The basic sensitivity formula is described. Absolute accuracy is explained and some of the problems associated with it are stressed.

Chapter 4, "Radiometer Principles," describes the four major classical radiometer principles: total power, Dicke, noise-injection, and correlation radiometers. Their sensitivities are derived from the basic sensitivity formula. It is also discussed how modern technology enables circuit implementations that softens the distinction between total power and Dicke radiometers (the hybrid radiometer). Additional radiometer principles are only briefly mentioned (for the sake of completeness), as they are not normally used for Earth sensing.

Chapter 5, "Radiometer Receivers on a Block Diagram Level," is an important engineering chapter. We discuss whether to use direct or superheterodyne receivers and how to combine double-sideband or single-sideband mixer operation (in the latter) with a possible microwave preamplifier. After that, a Dicke radiometer is worked through in detail on a block diagram level. Some specifications are fixed (frequency, bandwidth, and so forth) so that signal levels, gains, and...