Book excerpt: Written by one of the field’s leading experts, this landmark reference presents a thorough system analysis of the fiber-optic gyroscope (FOG), describing the concepts that have emerged as the preferred solutions for obtaining a practical device. This book’s first edition was published in the early 1990’s. If the basic design rules of the FOG have remained unchanged, the technology has certainly matured, and the expectations presented in the first edition have been largely exceeded. This second edition is updated throughout, featuring new content on Allan variance; testing with optical coherence domain polarimetry; the Shupe effect; and rare-Earth doped fiber ASE sources. In addition, brand new comprehensive appendixes cover the optics, single-mode fiber optics, and integrated optics necessary to understand the fiber gyro and provide an appropriate vocabulary for communicating with electronic component designers.