This book includes the PhD research entitled "Experimental consideration of channel capacity using Multiple Input Multiple Output (MIMO) technology". This work was carried out and completed in the Electronics, Telecommunications and Applied Physics Laboratory, in Physics Department at University of Ioannina, in Greece. Fundamental principles and performance aspects of MIMO systems and wireless channel propagation environment are included in the first chapter of the book. In the following chapters, MIMO platform design and implementation aspects are presented and discussed. The basic methodology that are used in a course of experimental measurements on SIMO and MIMO wireless channel propagation in indoor environment as well as the resulted observations are included in chapter 5. The concluding section of the book presents crucial considerations on MIMO wireless communication systems and proposes some improvements that will simplify the measurements on channel characterization