Book excerpt: Open Radio Access Network (O-RAN) Systems Architecture and Design gives a jump-start to engineers developing O-RAN hardware and software systems, providing a top-down approach to O-RAN systems design. It gives an introduction into why wireless systems look the way they do today before introducing relevant O-RAN and 3GPP standards. The remainder of the book discusses hardware and software aspects of O-RAN system design, including dimensioning and performance targets. - Presents O-RAN and 3GPP standards - Provides a top-down approach to O-RAN systems design - Includes practical examples of relevant elements of detailed hardware and software design to provide tools for development - Gives a few practical examples of where O-RAN designs play in the market and how they map to hardware and software architectures