In LEO satellite applications, a circularly polarized satellite antenna is desirable with a pattern that results in constant received power while the distance between the transmitter and the receiver is changing. A special type microstrip antenna satisfies these requirements along with their requirements for the satellite antenna. A complete theory, design, manufacture, test and evaluation processes of the microstrip patch antenna is discussed in this book. The book should be useful to professionals in antenna design. Especially the manufacture and test processes should help to new design engineers.