This book describes a wireless channel for system design with diverse mobile communication services, including propagation. It explains mobile propagation channels and analyses multi-path channel properties, the findings of which are validated by example experiments. The book explores such topics as: received signal level with wideband channels, street propagation using the Fresnel zone model, street cell design, space and polarization diversity antenna branch properties and their expressions, analysis models with space-frequency-path axes, SU-MIMO and MU-MIMO channel models, and MU-MIMO in 5G systems. The appendix explains these analysis processes in detail.