This white paper explores the basics of MIMO (multiple-in, multiple-out) communication technology, specifically focusing on the current generation of portable, tactical MIMO radios and the antenna technology that help make MIMO an attractive choice for today’s mobile wireless networks. This paper will touch upon topics related to the basics of understanding MIMO communication that can be understood by readers of all levels of technical levels, particularly those that are new to the RF market or have no previous working experience with MIMO technology.